molecular and cellular responses to childhood anthracycline exposure

3 downloads 46 Views 166KB Size Report
Sep 12, 2014 - Cardiovascular Proteomics Center, University of Texas Health Science Center San Antonio, San Antonio, Texas; 3Department of Epidemiology ...
Am J Physiol Heart Circ Physiol 307: H1379–H1389, 2014. First published September 12, 2014; doi:10.1152/ajpheart.00099.2014.

Review

The tell-tale heart: molecular and cellular responses to childhood anthracycline exposure Merry L. Lindsey,1 Richard A. Lange,2 Helen Parsons,3 Thomas Andrews,4 and Gregory J. Aune4 1

Department of Physiology and Biophysics, San Antonio Cardiovascular Proteomics Center and Jackson Center for Heart Research, Mississippi Medical Center, Jackson, Mississippi; 2Division of Cardiology, Department of Medicine, San Antonio Cardiovascular Proteomics Center, University of Texas Health Science Center San Antonio, San Antonio, Texas; 3Department of Epidemiology and Biostatistics, University of Texas Health Science Center San Antonio, San Antonio, Texas; and 4Division of Hematology-Oncology, Department of Pediatrics, Greehey Children’s Cancer Research Institute, University of Texas Health Science Center San Antonio, San Antonio, Texas Submitted 12 February 2014; accepted in final form 8 September 2014

Lindsey ML, Lange RA, Parsons H, Andrews T, Aune GJ. The tell-tale heart: molecular and cellular responses to childhood anthracycline exposure. Am J Physiol Heart Circ Physiol 307: H1379 –H1389, 2014. First published September 12, 2014; doi:10.1152/ajpheart.00099.2014.—Since the modern era of cancer chemotherapy that began in the mid-1940s, survival rates for children afflicted with cancer have steadily improved from 10% to current rates that approach 80% (60). Unfortunately, many long-term survivors of pediatric cancer develop chemotherapy-related health effects; 25% are afflicted with a severe or life-threatening medical condition, with cardiovascular disease being a primary risk (96). Childhood cancer survivors have markedly elevated incidences of stroke, congestive heart failure (CHF), coronary artery disease, and valvular disease (96). Their cardiac mortality is 8.2 times higher than expected (93). Anthracyclines are a key component of most curative chemotherapeutic regimens used in pediatric cancer, and approximately half of all childhood cancer patients are exposed to them (78). Numerous epidemiologic and observational studies have linked childhood anthracycline exposure to an increased risk of developing cardiomyopathy and CHF, often decades after treatment. The acute toxic effects of anthracyclines on cardiomyocytes are well described; however, myocardial tissue is comprised of additional resident cell types, and events occurring in the cardiomyocyte do not fully explain the pathological processes leading to late cardiomyopathy and CHF. This review will summarize the current literature regarding the cellular and molecular responses to anthracyclines, with an important emphasis on nonmyocyte cardiac cell types as well as those that mediate the myocardial injury response. anthracyclines; congestive heart failure; cardiomyopathy; cardiomyocytes; fibroblast; extracellular matrix

APPROXIMATELY 325,000 SURVIVORS of pediatric cancer currently reside in the United States, and 1 in 540 young adults is a cancer survivor (60). Anthracyclines are components of most curative combination chemotherapy regimens for childhood leukemia, lymphoma, and solid tumors, and approximately half of all newly diagnosed pediatric cancer patients will be treated with an anthracycline-containing regimen (78). Many of these individuals have, or are at risk of developing, chronic illnesses related to their childhood cancer treatments that adversely affect their long-term survival (6, 34, 55, 72, 93, 96). Cardiovascular disease and secondary malignancies are the two leading causes of premature death in pediatric cancer survivors (6). Reports of cardiovascular outcomes in pediatric cancer survivors treated with anthracyclines have focused primarily

Address for reprint requests and other correspondence: G. J. Aune, 8403 Floyd Curl Dr., MSC 7784, San Antonio, TX 78229 (e-mail: aune@uthscsa. edu). http://www.ajpheart.org

on clinical outcomes, current preventive strategies, or recommendations for clinical management (9, 22, 25, 38, 43, 44, 48, 68, 77– 83, 125, 126, 140). The rationale for our review is based on the following three observations. First, the clinical outcomes in anthracycline-exposed individuals are not completely explained by the known molecular effects of anthracyclines on the cardiac myocyte. Second, to our knowledge no recent review has focused on anthracycline cardiotoxicity in the nonmyocyte cell populations of the heart and those that mediate the myocardial injury response. Third, additional laboratory models are urgently needed to better understand the pathogenesis of heart disease in this population, and these models must account for both the observed clinical outcomes and the events that occur over time in the collective myocardial cell types that are responsible for pathological events at the organ level. Therefore, our review will 1) briefly summarize the clinical cardiovascular outcomes to provide the necessary clinical context and 2) focus on the molecular events that occur in

0363-6135/14 Copyright © 2014 the American Physiological Society

H1379

Review H1380

CHILDHOOD ANTHRACYCLINE EXPOSURE

the cell types that comprise myocardium and those that direct the responses that occur with injury. Because cardiac myocytes have historically been the central focus of anthracycline cardiotoxicity research, this review will be heavily weighted toward molecular events in them. Nevertheless, our overall goal is to highlight all myocardial cell types and injury response mechanisms that collectively guide the pathological development of disease in anthracycline-exposed patients. These cell types include immune cells that are part of the inflammatory reaction and resident cardiac fibroblasts that are part of the wound healing response and produce extracellular matrix (ECM). Developing a more balanced approach to understanding myocardial anthracycline-induced injury may facilitate the identification of novel targets to ameliorate the risk for cardiac disease in pediatric cancer survivors. Cardiovascular Outcomes in Long-Term Survivors of Pediatric Cancer Exposed to Anthracyclines Cardiovascular complications in anthracycline-exposed pediatric cancer survivors may manifest clinically as congestive heart failure (CHF), ischemic heart disease, stroke, or cardiac mortality. Cardiac imaging in these subjects may demonstrate functional or anatomic abnormalities such as cardiomyopathy, diastolic dysfunction, and valvular disease. These collective outcomes are important to consider in the context of understanding the interrelated events in anthracycline-exposed myocardial cell populations and the development of relevant preclinical laboratory models of anthracycline cardiotoxicity. A number of studies have demonstrated an increased risk for these cardiovascular outcomes, most of which have used the National Cancer Institute-funded U24 resources of the Childhood Cancer Survivor Study (CCSS). The CCSS is a multiinstitutional effort that has collected treatment and outcome data on 14,357 long-term childhood cancer survivors and 3,899 sibling controls (72). Oeffinger and colleagues (96) used data from this cohort to show that the relative risk (RR) of cardiovascular disease is markedly increased in long-term pediatric cancer survivors compared with matched sibling controls, including CHF (RR ⫽ 15.1), stroke (RR⫽ 9.3), and coronary artery disease (RR⫽ 10.4). Importantly, Mulrooney and colleagues (93) completed a study using the CCSS cohort in which the standardized mortality ratio (SMR) for cardiac death was 8.2 times higher than expected. These findings have been reinforced by new analysis of existing human cancer patient clinical registries by our team (manuscript in preparation.). These analyses provide further confirmation that childhood cancer survivors are at significantly higher risk of cardiovascular mortality compared with the general population (Fig. 1). Examining cardiovascular outcomes in a population-based cohort of childhood cancer survivors enrolled in the Surveillance, Epidemiology, and End Results Program (SEER) from 1980 to 1989, we found significantly higher cardiac mortality over time in survivors compared with the general population (Fig. 1A). Although the SMR for cancer survivors appears to decrease over time, it remains at least 10 times higher in long-term cancer survivors compared with the general population. The lower SMR over time is likely the result of aging of both survivors and the general population over time, when the incidence of cardiac events increases in both groups (Fig. 1B).

Fig. 1. Analysis of Surveillance Epidemiology and End Results (SEER) database to estimate death from cardiac causes in pediatric cancer survivors. A: standardized mortality ratio (SMR) for cardiac causes in pediatric cancer survivors compared with the general U.S. population. B: absolute death number from cardiac causes in pediatric cancer survivors compared with the general U.S. population.

Cardiac death in children and young adults is extremely rare, and any event drives large increases in the SMR compared with the general population of the same age. The important point remains that even 20 to 30 years after diagnosis, survivors of childhood and young adult cancers remain more than three times more likely to experience cardiac mortality compared with the general population. Studies using a variety of imaging modalities show that cardiac anatomic and functional characteristics are frequently abnormal in long-term survivors of pediatric cancer who have no clinical symptoms of cardiac disease. Lipshultz and colleagues (81) assessed echocardiographic outcomes in survivors of childhood cancer and noted lower left ventricular mass, wall thickness, contractility, and fractional shortening in anthracycline-exposed individuals compared with those who did not receive an anthracycline. In 277 adult survivors in the CCSS survey, Brouwer and colleagues (19) showed significantly higher rates of systolic and diastolic dysfunction in survivors compared with sibling controls as assessed by echocardiography.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review H1381

CHILDHOOD ANTHRACYCLINE EXPOSURE

Table 1. Drugs and strategies used to prevent anthracycline-induced cardiotoxicity Strategy

Deplete iron needed for ROS production Counteract ROS effects

Prevent apoptosis or regulate mitochondria

Regulate inflammatory response Miscellaneous or unknown

Therapy

Target or Mechanism

Reference

Dexrazoxane* Deferiprone# Monohydroxyethylrutoside# Pyroxyl 2-chlorobenzoyl hydrazine# Amifostine# CoQ10# Didox# Garlic extract# Glutathione-S-transferase# HO-3867# N-acetylcysteine# Probucol# Resveratrol# Schisandrin B# Tempol# Telmisartan - angiotensin II blocker# Trimetazidine# Vitamin E* Adiponectin# Bosentan# Endothelin-converting enzyme# PARP inhibitors# Phosphodiesterase-5 inhibitor# Pifithrin-␣# Thrombopoietin# Erythropoietin# FGF-2# Iloprost# ACE inihibitors* Administration rate Berberine# Liposomal delivery* Exercise* Metalloporphyrinic peroxynitrite decomposition catalyst# Statins*

Iron chelator Iron chelator Iron chelator Iron chelator Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antioxidant Antiapoptosis Antiapoptosis Mitochondrial regulation Antiapoptosis Antiapoptosis Antiapoptosis - anti-p53 Antiapoptosis Antioxidant and anti inflammatory Cytokine Synthetic prostaglandin 2Blood pressure/modify ECM remodeling 2Peak serum dose Unknown Selective delivery to tumors to limit off-target exposure 1Antioxidant production and reduce ECM remodeling Anti-nitric oxide

(49, 50, 76, 84, 85, 131) (3) (20, 21) (120) (13, 14) (29) (1) (2) (71) (30) (94) (36, 74, 75, 115) (35) (24, 137) (90) (47) (124) (47, 122) (88) (12) (89) (98) (63) (87) (23) (4) (116) (95) (15, 16, 51, 109) (11, 57, 82) (144) (104) (35, 56, 62) (97)

Antioxidant and anti-inflammatory

(113)

ROS, reactive oxygen species; CoQ10, coenzyme Q10; PARP, poly(ADP-ribose) polymerase; ACE, angiotensin-converting enzyme. *Clinical evidence. #Preclinical evidence.

Other studies have used more sensitive imaging methods to screen for subclinical cardiovascular complications in the survivor population. For example, Armstrong and colleagues (7) recently used cardiac MRI to study 108 anthracycline-exposed pediatric cancer survivors and found that 14% had a left ventricular ejection fraction of ⬍50% that was classified as normal by cardiac ultrasonography. Subclinical cardiac dysfunction [i.e., abnormal regional wall motion (138) and myocardial performance index (108)] has also been identified by echocardiographic studies of anthracycline-treated children, especially in those who received higher cumulative doses of the drug. The association between anthracycline exposure in childhood and the development of cardiac dysfunction later in life is well documented. Because of these studies, current recommendations are not to exceed anthracycline doses of 450 mg/m2. However, the underlying molecular mechanisms that explain the late onset of symptoms have not been fully elucidated. Etiology of Cardiomyopathy in Anthcracycline-Exposed Patients Anthracycline exposure in childhood initiates a pathological progression that may culminate in dilated cardiomyopathy in adulthood (64). In contrast to almost all other forms of cardiomyopathy, the major myocardial changes that occur after early

anthracycline exposure are predominantly found in the interstitial areas and do not result in extensive hypertrophy. Importantly, fibrosis is a major histologic change that occurs in survivors who have received anthracycline chemotherapies (10). Bernaba and colleagues (10) reviewed medical records from 10 patients who had a history of anthracycline exposure and available cardiac tissue samples (9 had cardiac transplantation as a result of anthracycline-induced heart failure). Histologic analysis revealed significant interstitial fibrosis in all 10 patients without hypertrophy. The molecular and cellular mechanisms that direct the development of anthracycline-induced cardiomyopathy remain largely unknown. With the combination of knowledge of pathological progression with the range of cellular and molecular effects, it is possible to speculate on novel targets and therapies for intervention. A number of studies have used existing knowledge to test protective strategies. A summary of these strategies is listed in Table 1. To identify new therapeutic strategies, it will be imperative to continue research aimed at elucidating the underlying molecular events and testing novel inhibitors in the context of the unique pathology of anthracycline-induced cardiac injury. This review will summarize what is currently known about the cellspecific effects and molecular events induced by anthracyclines in the cardiovascular system and heart.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review H1382

CHILDHOOD ANTHRACYCLINE EXPOSURE Myocytes HSF11 Nox2

PARP

NFAT5 TopII β

Fig. 2. Summary of myocardial cellular effects and the injury response induced by anthracyclines. Blue, absence abrogates cardiac dysfunction or protects from apoptosis; green, downregulation of mRNA and pathway inhibition; yellow, mediates apoptotic response; red, expression increases or enhances cardiac dysfunction; orange, absence enhances cardiac dysfunction. Anthracycline exposure increases p53, and global knockout abrogates the cardiotoxic response. HSF11, heat shock factor 11; Nox2, cofactor for NADPH oxidase; TopII␤, topoisomerase II-␤; HSP27, heat shock protein 27; PARP, poly(ADP-ribose)polymerase; HSP90, heat shock protein 90; GATA4, transcription factor; NFAT5, nuclear factor of activated T cells; mTOR, mammalian target of rapamycin; p38-MAPK, p38 mitogen-activated protein kinase; p-p300/CBP, phosphorylated p300/ CREB binding protein; BRCA2, breast cancer susceptibility gene 2; Bcl2:Bax ratio, ratio of B-cell lymphoma 2 to bcl2-like protein 4; miR146a, microRNA 146a; ROS, reactive oxygen species; CCPK-II, calcium calmodulin-dependent protein kinase II; Nrdp1, E3 ubiquitin ligase; Ub-proteasome, ubiquitinated proteasome; Casp3, caspase 3; Bax, bl2-like protein 4; Fas, ligand for Fas receptor; NF-␬B, nuclear factor-␬ light chain enhancer of activated B cells; MMPs, matrix metalloproteinases; TLR4, Toll-like receptor 4.

p53

HSP27

mTOR

GATA4

HSP90 p38-MapK BRCA2

Caveolin-3

p-p300/CBP

Caveolin-1

Bcl2:Bax Ratio

cytochrome C

miR-146a

p53

ROS

Neuregulin-1 CCPK-II Nrdp1

Ub-proteasome

Dystrophin

p21

?

?

Endothelial Cell

Casp3

Bax

Fas

Cardiac Progenitor Cell

telomeres

NFKappaB

?

?

? endothelin 1

endothelin 1

p16

? ?

?

Extracellular Matrix ? Fibroblast

Collagen

Immune Cells

?

Lymphocytes TLR4

Fibronectin MMPs Thrombospondin

Cell-Specific Myocardial Response to Anthracyclines The major mechanisms of anthracycline-induced myocardial damage that have been explored focus on the iron-dependent generation of reactive oxygen species (ROS) and the induction of cardiomyocyte apoptosis (25), with subsequent loss of myocytes and replacement fibrosis (31). Whereas these clearly important mechanisms explain the early loss of cardiac myocytes, they do not fully explain the complex series of events that occurs later when chemotherapy is completed or the events that occur in other cardiac cells—such as fibroblasts and invading immune cells—that are central mediators of the myocardial injury response (39). Additionally, anthracyclines may be arrhythmogenic during acute infusion (5, 46, 66, 103), injure vascular endothelial cells lining the coronary arteries and endocardium (28, 54, 117, 148), and affect cardiac progenitor cells (CPCs) (17, 31). The wide-ranging effects of anthracyclines on individual myocardial cell types are summarized in Fig. 2. As depicted in Fig. 2, much more information exists regarding the effects of anthracyclines on the myocyte than on all of the other cell types combined. Emerging data from clinical studies and experiments using cell types and animal models with specific

defects in the injury response strongly suggest an important role for these distinct cell types in anthracycline-induced cardiac injury. This review will summarize what is currently known about the molecular responses to anthracyclines in myocytes, endothelial cells, CPCs, and the cells coordinating the cardiac injury response. Myocytes. An extensive amount of experimental data regarding the mechanism of action of anthracyclines in myocytes has been collected, with most obtained in cultured mouse or rat cardiomyocyte cell lines isolated from animals ranging from neonatal age into adulthood. Whereas the generation of ROS has long been a known biological response to anthracyclines, a diverse array of other cellular pathways has also been implicated. However, the interactions among these pathways, their effects on other cell types in the myocardium, and the ECM remain largely unexplored. GENERATION OF REACTIVE OXYGEN SPECIES. In cultured cardiomyocytes, antioxidants protect against oxidative stress induced by doxorubicin (32). The Wallace laboratory (146) used an in vivo model of anthracycline exposure in adult male Sprague-Dawley rats to show elevated ROS formation in isolated cardiomyocytes that persisted for 5 wk after exposure

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review CHILDHOOD ANTHRACYCLINE EXPOSURE

was discontinued. Subsequent studies showed that disruption of redox pathways alters the deleterious response to anthracyclines. Turakhia and colleagues (127) used both small interfering RNA knockdown of heat shock protein 27 (HSP27) in cultured cardiomyocytes and heat shock transcription factor (HSF)-1⫺/⫺ cells to show that HSP27 protects against doxorubicin damage by preserving catalytic recycling required for maintaining appropriate redox balance. In cofactor for oxidase NADPH oxidase (Nox2)-deficient mice that lack NADPH oxidase, an important ROS source in myocytes, reduced ROS generation results in abrogated cardiac dysfunction, decreased myocyte apoptosis, and interstitial fibrosis (145). Metabolic studies using 13C isotope labeling in cultured cardiomyocytes demonstrated that oxidative metabolism was significantly increased during anthracyclines exposure, implying a relative increase in ROS (121). Finally, the Ren laboratory (134) used ventricular myocytes to show that doxorubicin-induced contractile dysfunction is mediated via p38 MAPK-dependent oxidative stress mechanisms (134). APOPTOSIS, DNA DAMAGE, AND DNA REPAIR PATHWAYS. The cytotoxic mechanisms of anthracyclines have been extensively studied in in vitro and in vivo tumor model systems. These studies demonstrate that anthracyclines damage DNA via intercalation and inhibition of topoisomerase II, an enzyme that relieves torsional strain on the DNA backbone during replication. This results in DNA strand breaks, induction of the DNA damage and repair pathways, and in the event the damage cannot be repaired initiation of the apoptotic response. Importantly, functional topoisomerase II has recently been implicated in the cardiotoxic response to doxorubicin. Zhang and colleagues (142) developed a mouse model with a cardiomyocyte-specific inducible knockout of the topoisomerase II␤ gene to show that doxorubicin-induced cardiotoxicity is abrogated in the absence of functional topoisomerase. In contrast, a recent article published by the Pommier laboratory (65) showed that absence of mitochondrial topoisomerase I resulted in impaired mitochondrial function and enhanced toxicity to doxorubicin. In vitro and in vivo studies have also shown that numerous cellular intermediates involved in the apoptotic response are altered in cardiomyocytes during anthracycline treatment. These include cytochrome c, Bcl-2-to-Bax ratio, and phosphorylation of p300/CREB binding protein (27, 101). In addition, caveolin 1 and 3 are required for the apoptotic response to doxorubicin (132). Alternatively, induction of cell survival pathways such as the WNT-1 pathway has been shown to block cardiomyocyte death in response to doxorubicin (130). Furthermore, the DNA repair and damage responses appear to be central to the mechanism of action of anthracycline-induced myocyte damage and have important functional significance. This is supported by all of the following: 1) acute doxorubicin cardiotoxicity is associated with p53-induced inhibition of mammalian target of rapamycin (147); 2) HSP27 (an important mediator of the ROS pathway) regulates p53 transcriptional activity in cultured cardiomyocytes and upregulates p21 to initiate cell cycle arrest (129); and 3) anthracycline-induced cardiotoxicity is abrogated in whole body p53-null mice. Interestingly, cardiomyocyte-specific ablation of p53 in mice using conditional knockdown techniques is not sufficient to block cardiac dysfunction or reduce cardiac fibrosis (37). Finally, alterations in pathways that respond directly to DNA damage have been studied in the context of anthracycline-

H1383

induced myocyte toxicity. These studies indicate the following: 1) deficiency in poly(ADP-ribose) polymerase, an enzyme that repairs DNA single strand breaks, results in protection against doxorubicin-induced damage (123) and 2) deficiency in breast cancer susceptibility gene-2 protein, a tumor suppressor protein, results in exaggerated cardiomyocyte apoptosis and cardiac failure in mouse models of anthracycline exposure (114). These observations highlight the overall importance of cellular DNA repair mechanisms in the response to anthracycline exposure. However, mechanisms have not been elucidated that explain why deficiency of some DNA repair pathways result in enhanced sensitivity to anthracyclines, whereas others are protective. Thus a greater understanding of how these pathways affect the response to anthracyclines in individual cell types in the myocardium may provide important further insights. NEUREGULIN/ERBB SIGNALING AXIS. Neuregulin-1 is an important growth and survival factor that exerts its function via the Erb-phosphatidylinositol 3-kinase-AKT pathway in the cardiomyocyte. Numerous in vitro studies have explored its role in the response to anthracyclines. These studies show the following: 1) treatment with neuregulin-1 protects myocytes from anthracycline-induced apoptosis (40); 2) HSP90 stabilizes ErbB2 protein following anthracycline exposure to protect against myocyte apoptosis (41); 3) heterozygous knockout of the neuregulin-1 gene in mice exacerbates heart failure caused by doxorubicin exposure (86); and 4) blocking the neuregulin axis with antibodies to ErbB2 (e.g., trastuzamab) initiates a similar apoptotic response to that obtained with daunorubicin exposure (107). Additionally microRNA-146a overexpression is induced by doxorubicin exposure and mediates cell death via interactions with the Erb-neuregulin signaling axis (53). ALTERATIONS IN TRANSCRIPTION FACTORS. A variety of studies have investigated the roles that individual transcription factors play in the cardiomyocyte response to anthracyclines. Krishnamurthy and colleagues (69) showed that ablation of transcription factor HSF-1 results in decreased expression of the multidrug resistance transporter P-glycoprotein and protection of cardiomyocytes from doxorubicin injury. Anthracyclines downregulate GATA4, an important survival factor (26, 99, 111), and decrease nuclear factor of activated T-cells 5 (NFAT5), a transcription factor that regulates osmotic-related stress. Interestingly, this is not mediated via changes in NFAT5 mRNA (58). DISRUPTION OF MYOFILAMENTS AND CALCIUM TRAFFICKING. A number of changes to myocyte filaments occur in response to anthracyclines exposure. In cultured neonatal rat myocytes, dose-dependent ultrastructural changes induced by anthracyclines include disorganization and depolymerization of actin filaments (73). Deng and colleagues (33) investigated cardiotoxicity in dystrophin-deficient mice and found them to be more sensitive to doxorubicin-induced cardiotoxicity than matched control mice. More recently, the Maier laboratory (110) showed that doxorubicin exposure stimulates Ca/calmodulin protein kinase II activation with increased calcium leak from the sarcoplasmic reticulum. ACTIVATION OF THE UBIQUITIN-PROTEASOME PATHWAY. The ubiquitin-proteasome is responsible for degradation of many cellular proteins and plays an essential role in homeostasis (105). In animal models, ubiquitin-proteasome activity is increased in cardiomyocytes exposed to anthracyclines (70).

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review H1384

CHILDHOOD ANTHRACYCLINE EXPOSURE

Other studies demonstrate stimulation of 20S proteasomes with doxorubicin exposure and exacerbation of doxorubicin-induced cardiac dysfunction in mice when the E3-ubiquitin ligase Nrdp1 is overexpressed (143). Endothelial cells. Several recent clinical studies have implicated vascular endothelium as an important target of the cardiovascular changes induced by anthracycline exposure. In two separate pilot studies, Mulrooney and colleagues (91, 92) studied 25 long-term survivors of Hodgkin’s lymphoma and 24 survivors of childhood osteosarcoma. Blood samples from these groups of patients exhibited evidence of vascular inflammation, dyslipidemia, and early atherogenesis. In a similar study, Brouwer and colleagues (18) studied 277 adult survivors of pediatric cancer who had received cardiotoxic therapies including anthracyclines. They observed an increase in arterial wall thickness, suggesting changes induced by exposure to systemic chemotherapy. In addition, Jenei and colleagues (61) studied 96 long-term survivors of pediatric cancer and noted that these patients had increased vascular stiffness. Zsary and colleagues (148) measured endothelin-1 levels (a critical regulator of cardiac performance) in 20 one-year survivors of lymphoma. They observed a decrease in plasma endothelin-1 levels that correlated with decreased ejection fraction and cardiac function. Collectively, these clinical studies suggest systemic chemotherapies such as anthracyclines can have deleterious effects on vascular endothelial cells and possibly contribute to long-term cardiac effects in survivors. The above clinical observations are further supported by substantial evidence from numerous preclinical studies that have investigated the cellular and molecular responses induced by anthracycline exposure in human endothelial cells. In contrast to clinical studies, Sayed-Ahmed and colleagues (112) observed an increase in plasma endothelin-1 in rats treated with anthracyclines. The discrepancy between the clinical and preclinical observations may be attributed to the time at which endothelin-1 was measured; in the clinical study by Zsary, endothelin-1 was quantified one year after completion of anthracycline treatment, whereas in the preclinical study measurements were taken at the immediate end of the treatment. While the direction of the change remains to be determined, the fact that endothelin-1 is changing in both clinical and preclinical models suggests that it might be an important regulator of anthracycline-induced cardiomyopathy. Hoch and colleagues (52) observed impaired endothelial differentiation in cells isolated from mice treated with doxorubicin. In addition, levels of erythropoietin in the cardiac microenvironment of these mice were reduced and microvasculature and endothelial differentiation were restored with

supplementation of an erythropoietin derivative. Yamac and colleagues (139) treated rats with anthracyclines and observed extensive degenerative changes in aorta endothelium in nuclei, ribosomes, and basement membrane. Using bovine aortic endothelial cells, Wang and colleagues (133) observed a time- and dose-dependent activation of nuclear factor-␬B (NF-␬B). Activation of NF-␬B and cell apoptosis were significantly decreased by adding glutathione peroxidase to reduce ROS. The findings suggest that in endothelial cells, anthracyclines induce NF-␬B leading to apoptosis, in contrast to cancer cells where activation of NF-␬B is antiapoptotic. Finally, Wu and colleagues (135) examined the effects of anthracycline exposure on the small coronary vessels of rats. In the endothelial cells that line these vessels, they noted an increase in proapoptotic caspase-3, Bax, and Fas, as well as a decrease in antiapoptotic Bcl-2. Collectively, these observations suggest that anthracyclines induce apoptosis in vascular endothelial cells, possibly leading to increased risk of cardiovascular disease later in life. Cardiac progenitor cells. A number of recent studies suggest that events in CPCs are an important contributing factor in the development of anthracycline-induced cardiomyopathy. De Angelis and colleagues (31) demonstrated that anthracycline treatment depletes the cardiac stem cell pool and that cardiac dysfunction can be restored by injecting cardiac stem cells systemically. In a separate study by the same group, CPCs grown in culture and exposed to doxorubicin were observed initiating the DNA damage response and undergoing apoptosis (100). At later time intervals, shortened telomeres and senescence were observed. In addition, the progeny of doxorubicintreated CPCs exhibited premature expression of p16(INK4a), an important marker for cellular senescence. This senescence phenotype is further supported by evidence published by Spallarosa and colleagues who exposed cord blood endothelial progenitor cells to low doses of doxorubicin and observed several important changes including increased SA-b-gal activity, decreased telomeric repeat binding factor 2, chromosomal abnormalities, enlarged cell shape, and disarrangement of Factin stress fibers (117). A recent review summarizes new observations linking cardiac toxicity from tyrosine kinase inhibitors (an emerging new class of anticancer agents) to cellular targets in CPCs and possibly other myocardial cell types (102). Collectively, these studies point to CPCs as an important cell type to study in the context of anthracycline-induced cardiomyopathy. The injury response: invading immune cells, fibroblasts, and ECM. The injury response in the heart is mediated by resident cardiac fibroblasts and is known to include complex interac-

Table 2. Future research priorities Attributes of Preclinical Laboratory Models Needed

Current Deficiency

Lack of pediatric focus Current models do not account for latent period between exposure and adverse cardiac outcomes Myocardial cell responses poorly understood, particularly for nonmyocyte cell types

Acute exposure in young animals with long latent period before evaluation Animal models that incorporate exposure in young animals and evaluation of cellular and functional parameters as they age Acute exposure models that differentiate responses by cell types and can be used to identify serum biomarkers

Clinical Trial Development

Organized prospective trials need to test long-term efficacy of novel cardioprotective interventions Validate biomarkers Test interventions that slow pathological progression to overt cardiac disease

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review CHILDHOOD ANTHRACYCLINE EXPOSURE

tions between invading immune cells and the ECM (39). The known myocardial effects of doxorubicin with respect to these events are summarized below. INVADING IMMUNE CELLS. Endomyocardial biopsy specimens obtained from patients exposed to anthracyclines exhibit myocarditis-like changes with prominent invasion by lymphocytes (42). Zhang and colleagues (141) described the presence of dendritic cells in the hearts of rats treated with doxorubicin. More recently, the innate immune system has been implicated in the mechanism of anthracycline-induced cardiotoxicity with Toll-like receptor-4 deficiency in mice abrogating doxorubicin cardiotoxicity (106). THROMBOSPONDIN. The matricellular protein thrombospondin is known to preserve ECM. Using a thrombospondin-1 knockout mouse model, van Almen and colleagues (128) showed that absence of thrombospondin increases doxorubicin-induced cardiomyocyte damage, disruption of ECM, and mortality in treated mice. MATRIX METALLOPROTEINASES. Matrix metalloproteinases (MMPs) are proteins that enzymatically alter the ECM following cardiac injury and collectively play a major role in the cardiac remodeling process. Recent studies emphasize the importance of ECM remodeling following doxorubicin exposure. Their findings include the following: 1) circulating MMPs can be detected in the serum of rats chronically exposed to doxorubicin (59); 2) proteomic analyses indicates cytstatin C increases with anthracycline exposure and inhibits cathespin B, resulting in increased myocardial fibronectin and collagen (119, 136); 3) increased circulating levels of ECM components are present in anthracycline-exposed animals (119, 136); and 4) alterations in tissue and circulating MMPs levels occur following exposure to anthracyclines (8, 45, 67, 118). Summary and Future Research Priorities Long-term survivors of pediatric cancer suffer from high rates of cardiovascular disease and cardiac mortality due to exposure to cardiotoxic chemotherapy and radiation in childhood. Anthracyclines are one of the most commonly used classes of chemotherapeutic agents in pediatric oncology, and their administration is associated with adverse cardiovascular outcomes that include CHF, cardiomyopathy, vascular disease, and stroke. Importantly, the widely held views regarding the molecular mechanisms that result in myocardial damage are often focused on the cardiomyocyte, although events in this solitary cell type do not fully explain how anthracycline exposure during childhood results in the clinical outcomes observed decades later. Collectively, these observations lay the foundation for developing the future research priorities we propose in Table 2. Consideration of the molecular events in response to anthracyclines in the various cell types that comprise myocardium is critical to identifying biomarkers of cardiotoxicity and novel cardioprotective therapeutics. In addition, a systematic understanding of how anthracyclines affect all myocardial cell types will allow for the development of novel hypotheses that are focused on elucidating the temporal and cellular relationships that occur in the heart following anthracycline exposure. Understanding these relationships will facilitate development of preclinical laboratory models and new strategies for detection, prevention, and management of cardiac disease in the large number of pediatric cancer survivors previously exposed

H1385

to anthracyclines. The clinical epidemiologic observations made regarding the long-term cardiac outcomes in survivors of pediatric cancer and the array of myocardial cellular events induced by anthracyclines summarized in this review provide the foundation for a concerted multidisciplinary approach. ACKNOWLEDGMENTS Present address of R. A. Lange: Paul L. Foster School of Medicine, Texas Tech Univ. Health Sciences Ctr. El Paso, El Paso, TX. GRANTS This study was supported by National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health (NIH) Grant 8UL1TR000149 (to G. J. Aune, KL2 Scholar); by National Cancer Institute Cancer Prevention and Control Career Development Award K07CA175063 (to H. Parsons); by a St. Baldrick’s Foundation Infrastructure grant (to H. Parsons and G. J. Aune); by NIH HHSN 268201000036C (N01-HV-00244) for the San Antonio Cardiovascular Proteomics Center, R01-HL-075360 and HL-051971, and from the Biomedical Laboratory Research and Development Service of the Veterans Affairs Office of Research and Development Award 5I01BX000505 (to M. L. Lindsey); and by the Rapoport Foundation for Cardiovascular Research (to R. A. Lange). The content presented here is solely the responsibility of the authors and does not necessarily represent the official views of the NIH or any other funding agency. DISCLOSURES No conflicts of interest, financial or otherwise, are declared by the author(s). AUTHOR CONTRIBUTIONS M.L.L., R.A.L., H.P., and G.J.A. prepared figures; M.L.L., R.A.L., and G.J.A. drafted manuscript; M.L.L., R.A.L., H.P., T.A., and G.J.A. edited and revised manuscript; M.L.L., R.A.L., H.P., T.A., and G.J.A. approved final version of manuscript. REFERENCES 1. Al-Abd AM, Al-Abbasi FA, Asaad GF, Abdel-Naim AB. Didox potentiates the cytotoxic profile of doxorubicin and protects from its cardiotoxicity. Eur J Pharmacol 718: 361–369, 2013. 2. Alkreathy HM, Damanhouri ZA, Ahmed N, Slevin M, Osman AM. Mechanisms of cardioprotective effect of aged garlic extract against Doxorubicin-induced cardiotoxicity. Integr Cancer Ther 11: 364 –370, 2012. 3. Ammar el-SM, Said SA, Suddek GM, El-Damarawy SL. Amelioration of doxorubicin-induced cardiotoxicity by deferiprone in rats. Can J Physiol Pharmacol 89: 269 –276, 2011. 4. Ammar HI, Saba S, Ammar RI, Elsayed LA, Ghaly WB, Dhingra S. Erythropoietin protects against doxorubicin-induced heart failure. Am J Physiol Heart Circ Physiol 301: H2413–H2421, 2011. 5. Arbel Y, Swartzon M, Justo D. QT prolongation and Torsades de Pointes in patients previously treated with anthracyclines. Anticancer Drugs 18: 493–498, 2007. 6. Armstrong GT, Liu Q, Yasui Y, Neglia JP, Leisenring W, Robison LL, Mertens AC. Late mortality among 5-year survivors of childhood cancer: a summary from the Childhood Cancer Survivor Study. J Clin Oncol 27: 2328 –2338, 2009. 7. Armstrong GT, Plana JC, Zhang N, Srivastava D, Green DM, Ness KK, Daniel Donovan F, Metzger ML, Arevalo A, Durand JB, Joshi V, Hudson MM, Robison LL, Flamm SD. Screening adult survivors of childhood cancer for cardiomyopathy: comparison of echocardiography and cardiac magnetic resonance imaging. J Clin Oncol 30: 2876 –2884, 2012. 8. Bai P, Mabley JG, Liaudet L, Virag L, Szabo C, Pacher P. Matrix metalloproteinase activation is an early event in doxorubicin-induced cardiotoxicity. Oncol Rep 11: 505–508, 2004. 9. Barry E, Alvarez JA, Scully RE, Miller TL, Lipshultz SE. Anthracycline-induced cardiotoxicity: course, pathophysiology, prevention and management. Expert Opin Pharmacother 8: 1039 –1058, 2007. 10. Bernaba BN, Chan JB, Lai CK, Fishbein MC. Pathology of late-onset anthracycline cardiomyopathy. Cardiovasc Pathol 19: 308 –311, 2010.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review H1386

CHILDHOOD ANTHRACYCLINE EXPOSURE

11. Berrak SG, Ewer MS, Jaffe N, Pearson P, Ried H, Zietz HA, Benjamin RS. Doxorubicin cardiotoxicity in children: reduced incidence of cardiac dysfunction associated with continuous-infusion schedules. Oncol Rep 8: 611–614, 2001. 12. Bien S, Riad A, Ritter CA, Gratz M, Olshausen F, Westermann D, Grube M, Krieg T, Ciecholewski S, Felix SB, Staudt A, Schultheiss HP, Ewert R, Volker U, Tschope C, Kroemer HK. The endothelin receptor blocker bosentan inhibits doxorubicin-induced cardiomyopathy. Cancer Res 67: 10428 –10435, 2007. 13. Bjelogrlic SK, Lukic ST, Djuricic SM. Activity of dexrazoxane and amifostine against late cardiotoxicity induced by the combination of doxorubicin and cyclophosphamide in vivo. Basic Clin Pharmacol Toxicol 113: 228 –238, 2013. 14. Bjelogrlic SK, Radic J, Radulovic S, Jokanovic M, Jovic V. Effects of dexrazoxane and amifostine on evolution of Doxorubicin cardiomyopathy in vivo. Exp Biol Med (Maywood) 232: 1414 –1424, 2007. 15. Blaes AH, Gaillard P, Peterson BA, Yee D, Virnig B. Angiotensin converting enzyme inhibitors may be protective against cardiac complications following anthracycline chemotherapy. Breast Cancer Res Treat 122: 585–590, 2010. 16. Bosch X, Rovira M, Sitges M, Domenech A, Ortiz-Perez JT, de Caralt TM, Morales-Ruiz M, Perea RJ, Monzo M, Esteve J. Enalapril and carvedilol for preventing chemotherapy-induced left ventricular systolic dysfunction in patients with malignant hemopathies: the OVERCOME trial (preventiOn of left Ventricular dysfunction with Enalapril and caRvedilol in patients submitted to intensive ChemOtherapy for the treatment of Malignant hEmopathies). J Am Coll Cardiol 61: 2355–2362, 2013. 17. Branco AF, Sampaio SF, Moreira AC, Holy J, Wallace KB, Baldeiras I, Oliveira PJ, Sardao VA. Differentiation-dependent doxorubicin toxicity on H9c2 cardiomyoblasts. Cardiovasc Toxicol 12: 326 –340, 2012. 18. Brouwer CA, Postma A, Hooimeijer HL, Smit AJ, Vonk JM, van Roon AM, van den Berg MP, Dolsma WV, Lefrandt JD, BinkBoelkens MT, Zwart N, de Vries EG, Tissing WJ, Gietema JA. Endothelial damage in long-term survivors of childhood cancer. J Clin Oncol 31: 3906 –3913, 2013. 19. Brouwer CA, Postma A, Vonk JM, Zwart N, van den Berg MP, Bink-Boelkens MT, Dolsma WV, Smit AJ, de Vries EG, Tissing WJ, Gietema JA. Systolic and diastolic dysfunction in long-term adult survivors of childhood cancer. Eur J Cancer 47: 2453–2462, 2011. 20. Bruynzeel AM, Abou El Hassan MA, Schalkwijk C, Berkhof J, Bast A, Niessen HW, van der Vijgh WJ. Anti-inflammatory agents and monoHER protect against DOX-induced cardiotoxicity and accumulation of CML in mice. Br J Cancer 96: 937–943, 2007. 21. Bruynzeel AM, Vormer-Bonne S, Bast A, Niessen HW, van der Vijgh WJ. Long-term effects of 7-monohydroxyethylrutoside (monoHER) on DOX-induced cardiotoxicity in mice. Cancer Chemother Pharmacol 60: 509 –514, 2007. 22. Carvalho C, Santos RX, Cardoso S, Correia S, Oliveira PJ, Santos MS, Moreira PI. Doxorubicin: the good, the bad and the ugly effect. Curr Med Chem 16: 3267–3285, 2009. 23. Chan KY, Xiang P, Zhou L, Li K, Ng PC, Wang CC, Zhang L, Deng HY, Pong NH, Zhao H, Chan WY, Sung RY. Thrombopoietin protects against doxorubicin-induced cardiomyopathy, improves cardiac function, and reversely alters specific signalling networks. Eur J Heart Fail 13: 366 –376, 2011. 24. Che F, Liu Y, Xu C. Prevention and treatment of doxorubicin-induced cardiotoxicity by dexrazoxane and schisandrin B in rabbits. Int J Toxicol 30: 681–689, 2011. 25. Chen B, Peng X, Pentassuglia L, Lim CC, Sawyer DB. Molecular and cellular mechanisms of anthracycline cardiotoxicity. Cardiovasc Toxicol 7: 114 –121, 2007. 26. Chen B, Zhong L, Roush SF, Pentassuglia L, Peng X, Samaras S, Davidson JM, Sawyer DB, Lim CC. Disruption of a GATA4/Ankrd1 signaling axis in cardiomyocytes leads to sarcomere disarray: implications for anthracycline cardiomyopathy. PLoS One 7: e35743, 2012. 27. Childs AC, Phaneuf SL, Dirks AJ, Phillips T, Leeuwenburgh C. Doxorubicin treatment in vivo causes cytochrome C release and cardiomyocyte apoptosis, as well as increased mitochondrial efficiency, superoxide dismutase activity, and Bcl-2:Bax ratio. Cancer Res 62: 4592– 4598, 2002.

28. Chow AY, Chin C, Dahl G, Rosenthal DN. Anthracyclines cause endothelial injury in pediatric cancer patients: a pilot study. J Clin Oncol 24: 925–928, 2006. 29. Conklin KA. Coenzyme q10 for prevention of anthracycline-induced cardiotoxicity. Int Cancer Ther 4: 110 –130, 2005. 30. Dayton A, Selvendiran K, Meduru S, Khan M, Kuppusamy ML, Naidu S, Kalai T, Hideg K, Kuppusamy P. Amelioration of doxorubicin-induced cardiotoxicity by an anticancer-antioxidant dual-function compound, HO-3867. J Pharmacol Expe Ther 339: 350 –357, 2011. 31. De Angelis A, Piegari E, Cappetta D, Marino L, Filippelli A, Berrino L, Ferreira-Martins J, Zheng H, Hosoda T, Rota M, Urbanek K, Kajstura J, Leri A, Rossi F, Anversa P. Anthracycline cardiomyopathy is mediated by depletion of the cardiac stem cell pool and is rescued by restoration of progenitor cell function. Circulation 121: 276 –292, 2010. 32. DeAtley SM, Aksenov MY, Aksenova MV, Harris B, Hadley R, Cole Harper P, Carney JM, Butterfield DA. Antioxidants protect against reactive oxygen species associated with adriamycin-treated cardiomyocytes. Cancer Lett 136: 41–46, 1999. 33. Deng S, Kulle B, Hosseini M, Schluter G, Hasenfuss G, Wojnowski L, Schmidt A. Dystrophin-deficiency increases the susceptibility to doxorubicin-induced cardiotoxicity. Eur J Heart Fail 9: 986 –994, 2007. 34. Diller L, Chow EJ, Gurney JG, Hudson MM, Kadin-Lottick NS, Kawashima TI, Leisenring WM, Meacham LR, Mertens AC, Mulrooney DA, Oeffinger KC, Packer RJ, Robison LL, Sklar CA. Chronic disease in the Childhood Cancer Survivor Study cohort: a review of published findings. J Clin Oncol 27: 2339 –2355, 2009. 35. Dolinsky VW, Rogan KJ, Sung MM, Zordoky BN, Haykowsky MJ, Young ME, Jones LW, Dyck JR. Both aerobic exercise and resveratrol supplementation attenuate doxorubicin-induced cardiac injury in mice. Am J Physiol Endocrinol Metab 305: E243–E253, 2013. 36. El-Demerdash E, Ali AA, Sayed-Ahmed MM, Osman AM. New aspects in probucol cardioprotection against doxorubicin-induced cardiotoxicity. Cancer Chemother Pharmacol 52: 411–416, 2003. 37. Feridooni T, Hotchkiss A, Remley-Carr S, Saga Y, Pasumarthi KB. Cardiomyocyte specific ablation of p53 is not sufficient to block doxorubicin induced cardiac fibrosis and associated cytoskeletal changes. PLoS One 6: e22801, 2011. 38. Franco VI, Henkel JM, Miller TL, Lipshultz SE. Cardiovascular effects in childhood cancer survivors treated with anthracyclines. Cardiol Res Pract 2011: 134679, 2011. 39. Frangogiannis NG. The immune system and cardiac repair. Pharmacol Res 58: 88 –111, 2008. 40. Fukazawa R, Miller TA, Kuramochi Y, Frantz S, Kim YD, Marchionni MA, Kelly RA, Sawyer DB. Neuregulin-1 protects ventricular myocytes from anthracycline-induced apoptosis via erbB4-dependent activation of PI3-kinase/Akt. J Mol Cell Cardiol 35: 1473–1479, 2003. 41. Gabrielson K, Bedja D, Pin S, Tsao A, Gama L, Yuan B, Muratore N. Heat shock protein 90 and ErbB2 in the cardiac response to doxorubicin injury. Cancer Res 67: 1436 –1441, 2007. 42. Gaudin PB, Hruban RH, Beschorner WE, Kasper EK, Olson JL, Baughman KL, Hutchins GM. Myocarditis associated with doxorubicin cardiotoxicity. Am J Clin Pathol 100: 158 –163, 1993. 43. Gianni L, Herman EH, Lipshultz SE, Minotti G, Sarvazyan N, Sawyer DB. Anthracycline cardiotoxicity: from bench to bedside. J Clin Oncol 26: 3777–3784, 2008. 44. Giantris A, Abdurrahman L, Hinkle A, Asselin B, Lipshultz SE. Anthracycline-induced cardiotoxicity in children and young adults. Crit Rev Oncol Hematol 27: 53–68, 1998. 45. Goetzenich A, Hatam N, Zernecke A, Weber C, Czarnotta T, Autschbach R, Christiansen S. Alteration of matrix metalloproteinases in selective left ventricular adriamycin-induced cardiomyopathy in the pig. J Heart Lung Transplant 28: 1087–1093, 2009. 46. Guglin M, Aljayeh M, Saiyad S, Ali R, Curtis AB. Introducing a new entity: chemotherapy-induced arrhythmia. Europace 11: 1579 –1586, 2009. 47. Hadi N, Yousif NG, Al-amran FG, Huntei NK, Mohammad BI, Ali SJ. Vitamin E and telmisartan attenuates doxorubicin induced cardiac injury in rat through down regulation of inflammatory response. BMC Cardiovasc Disord 12: 63, 2012. 48. Harake D, Franco VI, Henkel JM, Miller TL, Lipshultz SE. Cardiotoxicity in childhood cancer survivors: strategies for prevention and management. Future Cardiol 8: 647–670, 2012.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review CHILDHOOD ANTHRACYCLINE EXPOSURE 49. Hasinoff BB, Herman EH. Dexrazoxane: how it works in cardiac and tumor cells. Is it a prodrug or is it a drug? Cardiovasc Toxicol 7: 140 –144, 2007. 50. Herman EH, Zhang J, Rifai N, Lipshultz SE, Hasinoff BB, Chadwick DP, Knapton A, Chai J, Ferrans VJ. The use of serum levels of cardiac troponin T to compare the protective activity of dexrazoxane against doxorubicin- and mitoxantrone-induced cardiotoxicity. Cancer Chemother Pharmacol 48: 297–304, 2001. 51. Hiona A, Lee AS, Nagendran J, Xie X, Connolly AJ, Robbins RC, Wu JC. Pretreatment with angiotensin-converting enzyme inhibitor improves doxorubicin-induced cardiomyopathy via preservation of mitochondrial function. J Thorac Cardiovasc Surg 142: 396 –403, 2011. 52. Hoch M, Fischer P, Stapel B, Missol-Kolka E, Sekkali B, Scherr M, Favret F, Braun T, Eder M, Schuster-Gossler K, Gossler A, Hilfiker A, Balligand JL, Drexler H, Hilfiker-Kleiner D. Erythropoietin preserves the endothelial differentiation capacity of cardiac progenitor cells and reduces heart failure during anticancer therapies. Cell Stem Cell 9: 131–143, 2011. 53. Horie T, Ono K, Nishi H, Nagao K, Kinoshita M, Watanabe S, Kuwabara Y, Nakashima Y, Takanabe-Mori R, Nishi E, Hasegawa K, Kita T, Kimura T. Acute doxorubicin cardiotoxicity is associated with miR-146a-induced inhibition of the neuregulin-ErbB pathway. Cardiovasc Res 87: 656 –664, 2010. 54. Huang C, Zhang X, Ramil JM, Rikka S, Kim L, Lee Y, Gude NA, Thistlethwaite PA, Sussman MA, Gottlieb RA, Gustafsson AB. Juvenile exposure to anthracyclines impairs cardiac progenitor cell function and vascularization resulting in greater susceptibility to stress-induced myocardial injury in adult mice. Circulation 121: 675–683, 2010. 55. Hudson MM, Mertens AC, Yasui Y, Hobbie W, Chen H, Gurney JG, Yeazel M, Recklitis CJ, Marina N, Robison LR, Oeffinger KC. Health status of adult long-term survivors of childhood cancer: a report from the Childhood Cancer Survivor Study. JAMA 290: 1583–1592, 2003. 56. Hydock DS, Lien CY, Jensen BT, Schneider CM, Hayward R. Exercise preconditioning provides long-term protection against early chronic doxorubicin cardiotoxicity. Integr Cancer Ther 10: 47–57, 2011. 57. Ishisaka T, Kishi S, Okura K, Horikoshi M, Yamashita T, Mitsuke Y, Shimizu H, Ueda T. A precise pharmacodynamic study showing the advantage of a marked reduction in cardiotoxicity in continuous infusion of doxorubicin. Leuk Lymphoma 47: 1599 –1607, 2006. 58. Ito T, Fujio Y, Takahashi K, Azuma J. Degradation of NFAT5, a transcriptional regulator of osmotic stress-related genes, is a critical event for doxorubicin-induced cytotoxicity in cardiac myocytes. J Biol Chem 282: 1152–1160, 2007. 59. Ivanova M, Dovinova I, Okruhlicova L, Tribulova N, Simoncikova P, Barte-kova M, Vlkovicova J, Barancik M. Chronic cardiotoxicity of doxorubicin involves activation of myocardial and circulating matrix metalloproteinases in rats. Acta Pharmacol Sin 33: 459 –469, 2012. 60. Jemal A, Siegel R, Xu J, Ward E. Cancer statistics, 2010. CA Cancer J Clin 60: 277–300, 2010. 61. Jenei Z, Bardi E, Magyar MT, Horvath A, Paragh G, Kiss C. Anthracycline causes impaired vascular endothelial function and aortic stiffness in long term survivors of childhood cancer. Pathol Oncol Res 19: 375–383, 2013. 62. Jensen BT, Lien CY, Hydock DS, Schneider CM, Hayward R. Exercise mitigates cardiac doxorubicin accumulation and preserves function in the rat. J Cardiovasc Pharmacol 62: 263–269, 2013. 63. Jin Z, Zhang J, Zhi H, Hong B, Zhang S, Guo H, Li L. Beneficial effects of tadalafil on left ventricular dysfunction in doxorubicin-induced cardiomyopathy. J Cardiol 62: 110 –116, 2013. 64. Katamadze NA, Lartsuliani KP, Kiknadze MP. Left ventricular function in patients with toxic cardiomyopathy and with idiopathic dilated cardiomyopathy treated with Doxorubicin. Georgian Med News 166: 43–48, 2009. 65. Khiati S, Dalla Rosa I, Sourbier C, Ma X, Rao VA, Neckers LM, Zhang H, Pommier Y. Mitochondrial topoisomerase I (Top1mt) is a novel limiting factor of doxorubicin cardiotoxicity. Clin Cancer Res 20: 4873–4881, 2014. 66. Kilickap S, Barista I, Akgul E, Aytemir K, Aksoy S, Tekuzman G. Early and late arrhythmogenic effects of doxorubicin. South Med J 100: 262–265, 2007. 67. Kizaki K, Ito R, Okada M, Yoshioka K, Uchide T, Temma K, Mutoh K, Uechi M, Hara Y. Enhanced gene expression of myocardial matrix metalloproteinases 2 and 9 after acute treatment with doxorubicin in mice. Pharmacol Res 53: 341–346, 2006.

H1387

68. Krischer JP, Epstein S, Cuthbertson DD, Goorin AM, Epstein ML, Lipshultz SE. Clinical cardiotoxicity following anthracycline treatment for childhood cancer: the Pediatric Oncology Group experience. J Clin Oncol 15: 1544 –1552, 1997. 69. Krishnamurthy K, Vedam K, Kanagasabai R, Druhan LJ, Ilangovan G. Heat shock factor-1 knockout induces multidrug resistance gene, MDR1b, and enhances P-glycoprotein (ABCB1)-based drug extrusion in the heart. Proc Natl Acad Sci USA 109: 9023–9028, 2012. 70. Kumarapeli AR, Horak KM, Glasford JW, Li J, Chen Q, Liu J, Zheng H, Wang X. A novel transgenic mouse model reveals deregulation of the ubiquitin-proteasome system in the heart by doxorubicin. FASEB J 19: 2051–2053, 2005. 71. L’Ecuyer T, Allebban Z, Thomas R, Vander Heide R. Glutathione S-transferase overexpression protects against anthracycline-induced H9C2 cell death. Am J Physiol Heart Circ Physiol 286: H2057–H2064, 2004. 72. Leisenring WM, Mertens AC, Armstrong GT, Stovall MA, Neglia JP, Lanctot JQ, Boice JD Jr, Whitton JA, Yasui Y. Pediatric cancer survivorship research: experience of the Childhood Cancer Survivor Study. J Clin Oncol 27: 2319 –2327, 2009. 73. Lewis W, Gonzalez B. Anthracycline effects on actin and actin-containing thin filaments in cultured neonatal rat myocardial cells. Lab Invest 54: 416 –423, 1986. 74. Li T, Danelisen I, Bello-Klein A, Singal PK. Effects of probucol on changes of antioxidant enzymes in adriamycin-induced cardiomyopathy in rats. Cardiovasc Res 46: 523–530, 2000. 75. Li T, Singal PK. Adriamycin-induced early changes in myocardial antioxidant enzymes and their modulation by probucol. Circulation 102: 2105–2110, 2000. 76. Lipshultz SE. Dexrazoxane for protection against cardiotoxic effects of anthracyclines in children. J Clin Oncol 14: 328 –331, 1996. 77. Lipshultz SE, Adams MJ. Cardiotoxicity after childhood cancer: beginning with the end in mind. J Clin Oncol 28: 1276 –1281, 2010. 78. Lipshultz SE, Alvarez JA, Scully RE. Anthracycline associated cardiotoxicity in survivors of childhood cancer. Heart 94: 525–533, 2008. 79. Lipshultz SE, Cochran TR, Franco VI, Miller TL. Treatment-related cardiotoxicity in survivors of childhood cancer. Nat Rev Clin Oncol 10: 697–710, 2013. 80. Lipshultz SE, Karnik R, Sambatakos P, Franco VI, Ross SW, Miller TL. Anthracycline-related cardiotoxicity in childhood cancer survivors. Curr Opin Cardiol 29: 103–112, 2014. 81. Lipshultz SE, Landy DC, Lopez-Mitnik G, Lipsitz SR, Hinkle AS, Constine LS, French CA, Rovitelli AM, Proukou C, Adams MJ, Miller TL. Cardiovascular status of childhood cancer survivors exposed and unexposed to cardiotoxic therapy. J Clin Oncol 30: 1050 –1057, 2012. 82. Lipshultz SE, Miller TL, Lipsitz SR, Neuberg DS, Dahlberg SE, Colan SD, Silverman LB, Henkel JM, Franco VI, Cushman LL, Asselin BL, Clavell LA, Athale U, Michon B, Laverdiere C, Schorin MA, Larsen E, Usmani N, Sallan SE,; and Dana-Farber Cancer Institute Acute Lymphoblastic Leukemia Consortium. Continuous versus bolus infusion of doxorubicin in children with all: long-term cardiac outcomes. Pediatrics 130: 1003–1011, 2012. 83. Lipshultz SE, Miller TL, Scully RE, Lipsitz SR, Rifai N, Silverman LB, Colan SD, Neuberg DS, Dahlberg SE, Henkel JM, Asselin BL, Athale UH, Clavell LA, Laverdiere C, Michon B, Schorin MA, Sallan SE. Changes in cardiac biomarkers during doxorubicin treatment of pediatric patients with high-risk acute lymphoblastic leukemia: associations with long-term echocardiographic outcomes. J Clin Oncol 30: 1042–1049, 2012. 84. Lipshultz SE, Rifai N, Dalton VM, Levy DE, Silverman LB, Lipsitz SR, Colan SD, Asselin BL, Barr RD, Clavell LA, Hurwitz CA, Moghrabi A, Samson Y, Schorin MA, Gelber RD, Sallan SE. The effect of dexrazoxane on myocardial injury in doxorubicin-treated children with acute lymphoblastic leukemia. N Engl J Med 351: 145–153, 2004. 85. Lipshultz SE, Scully RE, Lipsitz SR, Sallan SE, Silverman LB, Miller TL, Barry EV, Asselin BL, Athale U, Clavell A, Larsen E, Moghrabi A, Samson Y, Michon B, Schorin MA, Cohen HJ, Neuberg DS, Orav EJ, Colan SD. Assessment of dexrazoxane as a cardioprotectant in doxorubicin-treated children with high-risk acute lymphoblastic leukaemia: long-term follow-up of a prospective, randomised, multicentre trial. Lancet Oncol 11: 950 –961, 2010.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review H1388

CHILDHOOD ANTHRACYCLINE EXPOSURE

86. Liu FF, Stone JR, Schuldt AJ, Okoshi K, Okoshi MP, Nakayama M, Ho KK, Manning WJ, Marchionni MA, Lorell BH, Morgan JP, Yan X. Heterozygous knockout of neuregulin-1 gene in mice exacerbates doxorubicin-induced heart failure. Am J Physiol Heart Circ Physiol 289: H660 –H666, 2005. 87. Liu X, Chua CC, Gao J, Chen Z, Landy CL, Hamdy R, Chua BH. Pifithrin-␣ protects against doxorubicin-induced apoptosis and acute cardiotoxicity in mice. Am J Physiol Heart Circ Physiol 286: H933– H939, 2004. 88. Maruyama S, Shibata R, Ohashi K, Ohashi T, Daida H, Walsh K, Murohara T, Ouchi N. Adiponectin ameliorates doxorubicin-induced cardiotoxicity through Akt protein-dependent mechanism. J Biol Chem 286: 32790 –32800, 2011. 89. Miyagawa K, Emoto N, Widyantoro B, Nakayama K, Yagi K, Rikitake Y, Suzuki T, Hirata K. Attenuation of Doxorubicin-induced cardiomyopathy by endothelin-converting enzyme-1 ablation through prevention of mitochondrial biogenesis impairment. Hypertension 55: 738 –746, 2010. 90. Monti E, Cova D, Guido E, Morelli R, Oliva C. Protective effect of the nitroxide tempol against the cardiotoxicity of adriamycin. Free Radic Biol Med 21: 463–470, 1996. 91. Mulrooney DA, Ness KK, Huang S, Solovey A, Hebbel RP, Neaton JD, Clohisy DR, Kelly AS, Neglia JP. Pilot study of vascular health in survivors of osteosarcoma. Pediatr Blood Cancer 60: 1703–1708, 2013. 92. Mulrooney DA, Ness KK, Solovey A, Hebbel RP, Neaton JD, Peterson BA, Lee CK, Kelly AS, Neglia JP. Pilot study of vascular health in survivors of Hodgkin lymphoma. Pediatr Blood Cancer 59: 285–289, 2012. 93. Mulrooney DA, Yeazel MW, Kawashima T, Mertens AC, Mitby P, Stovall M, Donaldson SS, Green DM, Sklar CA, Robison LL, Leisenring WM. Cardiac outcomes in a cohort of adult survivors of childhood and adolescent cancer: retrospective analysis of the Childhood Cancer Survivor Study cohort. BMJ 339: b4606, 2009. 94. Myers C, Bonow R, Palmeri S, Jenkins J, Corden B, Locker G, Doroshow J, Epstein S. A randomized controlled trial assessing the prevention of doxorubicin cardiomyopathy by N-acetylcysteine. Semin Oncol 10: 53–55, 1983. 95. Neilan TG, Jassal DS, Scully MF, Chen G, Deflandre C, McAllister H, Kay E, Austin SC, Halpern EF, Harmey JH, Fitzgerald DJ. Iloprost attenuates doxorubicin-induced cardiac injury in a murine model without compromising tumour suppression. Eur Heart J 27: 1251–1256, 2006. 96. Oeffinger KC, Mertens AC, Sklar CA, Kawashima T, Hudson MM, Meadows AT, Friedman DL, Marina N, Hobbie W, Kadan-Lottick NS, Schwartz CL, Leisenring W, Robison LL. Chronic health conditions in adult survivors of childhood cancer. N Engl J Med 355: 1572–1582, 2006. 97. Pacher P, Liaudet L, Bai P, Mabley JG, Kaminski PM, Virag L, Deb A, Szabo E, Ungvari Z, Wolin MS, Groves JT, Szabo C. Potent metalloporphyrin peroxynitrite decomposition catalyst protects against the development of doxorubicin-induced cardiac dysfunction. Circulation 107: 896 –904, 2003. 98. Pacher P, Liaudet L, Mabley JG, Cziraki A, Hasko G, Szabo C. Beneficial effects of a novel ultrapotent poly(ADP-ribose) polymerase inhibitor in murine models of heart failure. Int J Mol Med 7: 369 –375, 2006. 99. Park AM, Nagase H, Liu L, Vinod Kumar S, Szwergold N, Wong CM, Suzuki YJ. Mechanism of anthracycline-mediated down-regulation of GATA4 in the heart. Cardiovasc Res 90: 97–104, 2011. 100. Piegari E, De Angelis A, Cappetta D, Russo R, Esposito G, Costantino S, Graiani G, Frati C, Prezioso L, Berrino L, Urbanek K, Quaini F, Rossi F. Doxorubicin induces senescence and impairs function of human cardiac progenitor cells. Basic Res Cardiol 108: 334, 2013. 101. Poizat C, Puri PL, Bai Y, Kedes L. Phosphorylation-dependent degradation of p300 by doxorubicin-activated p38 mitogen-activated protein kinase in cardiac cells. Mol Cell Biol 25: 2673–2687, 2005. 102. Prezioso L, Tanzi S, Galaverna F, Frati C, Testa B, Savi M, Graiani G, Lagrasta C, Cavalli S, Galati S, Madeddu D, Lodi Rizzini E, Ferraro F, Musso E, Stilli D, Urbanek K, Piegari E, De Angelis A, Maseri A, Rossi F, Quaini E, Quaini F. Cancer treatment-induced cardiotoxicity: a cardiac stem cell disease? Cardiovasc Hematol Agents Med Chem 8: 55–75, 2010.

103. Pudil R, Horacek JM, Horackova J, Jebavy L, Vojacek J. Anthracycline therapy can induce very early increase in QT dispersion and QTc prolongation. Leuk Res 32: 998 –999, 2008. 104. Rafiyath SM, Rasul M, Lee B, Wei G, Lamba G, Liu D. Comparison of safety and toxicity of liposomal doxorubicin vs. conventional anthracyclines: a meta-analysis. Exp Hematol Oncol 1: 10, 2012. 105. Ranek MJ, Wang X. Activation of the ubiquitin-proteasome system in doxorubicin cardiomyopathy. Curr Hypertens Rep 11: 389 –395, 2009. 106. Riad A, Bien S, Gratz M, Escher F, Westermann D, Heimesaat MM, Bereswill S, Krieg T, Felix SB, Schultheiss HP, Kroemer HK, Tschope C. Toll-like receptor-4 deficiency attenuates doxorubicin-induced cardiomyopathy in mice. Eur J Heart Fail 10: 233–243, 2008. 107. Rohrbach S, Muller-Werdan U, Werdan K, Koch S, Gellerich NF, Holtz J. Apoptosis-modulating interaction of the neuregulin/erbB pathway with anthracyclines in regulating Bcl-xS and Bcl-xL in cardiomyocytes. J Mol Cell Cardiol 38: 485–493, 2005. 108. Ruggiero A, De Rosa G, Rizzo D, Leo A, Maurizi P, De Nisco A, Vendittelli F, Zuppi C, Mordente A, Riccardi R. Myocardial performance index and biochemical markers for early detection of doxorubicininduced cardiotoxicity in children with acute lymphoblastic leukaemia. Int J Clin Oncol 2012. 109. Sacco G, Mario B, Lopez G, Evangelista S, Manzini S, Maggi CA. ACE inhibition and protection from doxorubicin-induced cardiotoxicity in the rat. Vascular pharmacology 50: 166 –170, 2009. 110. Sag CM, Kohler AC, Anderson ME, Backs J, Maier LS. CaMKIIdependent SR Ca leak contributes to doxorubicin-induced impaired Ca handling in isolated cardiac myocytes. J Mol Cell Cardiol 51: 749 –759, 2011. 111. Salisch S, Klar M, Thurisch B, Bungert J, Dame C. Gata4 and Sp1 regulate expression of the erythropoietin receptor in cardiomyocytes. J Cell Mol Med 15: 1963–1972, 2011. 112. Sayed-Ahmed MM, Khattab MM, Gad MZ, Osman AM. Increased plasma endothelin-1 and cardiac nitric oxide during doxorubicin-induced cardiomyopathy. Pharmacol Toxicol 89: 140 –144, 2001. 113. Seicean S, Seicean A, Plana JC, Budd GT, Marwick TH. Effect of statin therapy on the risk for incident heart failure in patients with breast cancer receiving anthracycline chemotherapy: an observational clinical cohort study. J Am Coll Cardiol 60: 2384 –2390, 2012. 114. Singh KK, Shukla PC, Quan A, Desjardins JF, Lovren F, Pan Y, Garg V, Gosal S, Garg A, Szmitko PE, Schneider MD, Parker TG, Stanford WL, Leong-Poi H, Teoh H, Al-Omran M, Verma S. BRCA2 protein deficiency exaggerates doxorubicin-induced cardiomyocyte apoptosis and cardiac failure. J Biol Chem 287: 6604 –6614, 2012. 115. Siveski-Iliskovic N, Kaul N, Singal PK. Probucol promotes endogenous antioxidants and provides protection against adriamycin-induced cardiomyopathy in rats. Circulation 89: 2829 –2835, 1994. 116. Sontag DP, Wang J, Kardami E, Cattini PA. FGF-2 and FGF-16 protect isolated perfused mouse hearts from acute doxorubicin-induced contractile dysfunction. Cardiovasc Toxicol 13: 244 –253, 2013. 117. Spallarossa P, Altieri P, Barisione C, Passalacqua M, Aloi C, Fugazza G, Frassoni F, Podesta M, Canepa M, Ghigliotti G, Brunelli C. p38 MAPK and JNK antagonistically control senescence and cytoplasmic p16INK4A expression in doxorubicin-treated endothelial progenitor cells. PLoS One 5: e15583, 2010. 118. Spallarossa P, Altieri P, Garibaldi S, Ghigliotti G, Barisione C, Manca V, Fabbi P, Ballestrero A, Brunelli C, Barsotti A. Matrix metalloproteinase-2 and -9 are induced differently by doxorubicin in H9c2 cells: the role of MAP kinases and NAD(P)H oxidase. Cardiovasc Res 69: 736 –745, 2006. 119. Sterba M, Popelova O, Lenco J, Fucikova A, Brcakova E, Mazurova Y, Jirkovsky E, Simunek T, Adamcova M, Micuda S, Stulik J, Gersl V. Proteomic insights into chronic anthracycline cardiotoxicity. J Mol Cell Cardiol 50: 849 –862, 2011. 120. Sterba M, Popelova O, Simunek T, Mazurova Y, Potacova A, Adamcova M, Kaiserova H, Ponka P, Gersl V. Cardioprotective effects of a novel iron chelator, pyridoxal 2-chlorobenzoyl hydrazone, in the rabbit model of daunorubicin-induced cardiotoxicity. J Pharmacol Exp Ther 319: 1336 –1347, 2006. 121. Strigun A, Wahrheit J, Niklas J, Heinzle E, Noor F. Doxorubicin increases oxidative metabolism in HL-1 cardiomyocytes as shown by 13C metabolic flux analysis. Toxicol Sci 125: 595–606, 2012. 122. Suhail N, Bilal N, Khan HY, Hasan S, Sharma S, Khan F, Mansoor T, Banu N. Effect of vitamins C and E on antioxidant status of

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org

Review CHILDHOOD ANTHRACYCLINE EXPOSURE

123.

124.

125.

126. 127.

128.

129.

130.

131.

132.

133.

breast-cancer patients undergoing chemotherapy. J Clin Pharm Ther 37: 22–26, 2012. Szanto M, Rutkai I, Hegedus C, Czikora A, Rozsahegyi M, Kiss B, Virag L, Gergely P, Toth A, Bai P. Poly(ADP-ribose) polymerase-2 depletion reduces doxorubicin-induced damage through SIRT1 induction. Cardiovasc Res 92: 430 –438, 2011. Tallarico D, Rizzo V, Di Maio F, Petretto F, Bianco G, Placanica G, Marziali M, Paravati V, Gueli N, Meloni F, Campbell SV. Myocardial cytoprotection by trimetazidine against anthracycline-induced cardiotoxicity in anticancer chemotherapy. Angiology 54: 219 –227, 2003. Thompson KL, Rosenzweig BA, Zhang J, Knapton AD, Honchel R, Lipshultz SE, Retief J, Sistare FD, Herman EH. Early alterations in heart gene expression profiles associated with doxorubicin cardiotoxicity in rats. Cancer Chemother Pharmacol 66: 303–314, 2010. Trachtenberg BH, Landy DC, Franco VI, Henkel JM, Pearson EJ, Miller TL, Lipshultz SE. Anthracycline-associated cardiotoxicity in survivors of childhood cancer. Pediatr Cardiol 32: 342–353, 2011. Turakhia S, Venkatakrishnan CD, Dunsmore K, Wong H, Kuppusamy P, Zweier JL, Ilangovan G. Doxorubicin-induced cardiotoxicity: direct correlation of cardiac fibroblast and H9c2 cell survival and aconitase activity with heat shock protein 27. Am J Physiol Heart Circ Physiol 293: H3111–H3121, 2007. van Almen GC, Swinnen M, Carai P, Verhesen W, Cleutjens JP, D’Hooge J, Verheyen FK, Pinto YM, Schroen B, Carmeliet P, Heymans S. Absence of thrombospondin-2 increases cardiomyocyte damage and matrix disruption in doxorubicin-induced cardiomyopathy. J Mol Cell Cardiol 51: 318 –328, 2011. Venkatakrishnan CD, Dunsmore K, Wong H, Roy S, Sen CK, Wani A, Zweier JL, Ilangovan G. HSP27 regulates p53 transcriptional activity in doxorubicin-treated fibroblasts and cardiac H9c2 cells: p21 upregulation and G2/M phase cell cycle arrest. Am J Physiol Heart Circ Physiol 294: H1736 –H1744, 2008. Venkatesan B, Prabhu SD, Venkatachalam K, Mummidi S, Valente AJ, Clark RA, Delafontaine P, Chandrasekar B. WNT1-inducible signaling pathway protein-1 activates diverse cell survival pathways and blocks doxorubicin-induced cardiomyocyte death. Cell Signal 22: 809 – 820, 2010. Venturini M, Michelotti A, Del Mastro L, Gallo L, Carnino F, Garrone O, Tibaldi C, Molea N, Bellina RC, Pronzato P, Cyrus P, Vinke J, Testore F, Guelfi M, Lionetto R, Bruzzi P, Conte PF, Rosso R. Multicenter randomized controlled clinical trial to evaluate cardioprotection of dexrazoxane versus no cardioprotection in women receiving epirubicin chemotherapy for advanced breast cancer. J Clin Oncol 14: 3112–3120, 1996. Volonte D, McTiernan CF, Drab M, Kasper M, Galbiati F. Caveolin-1 and caveolin-3 form heterooligomeric complexes in atrial cardiac myocytes that are required for doxorubicin-induced apoptosis. Am J Physiol Heart Circ Physiol 294: H392–H401, 2008. Wang S, Kotamraju S, Konorev E, Kalivendi S, Joseph J, Kalyanaraman B. Activation of nuclear factor-kappaB during doxorubicininduced apoptosis in endothelial cells and myocytes is pro-apoptotic: the role of hydrogen peroxide. Biochem J 367: 729 –740, 2002.

H1389

134. Wold LE, Aberle NS, 2nd, Ren J. Doxorubicin induces cardiomyocyte dysfunction via a p38 MAP kinase-dependent oxidative stress mechanism. Cancer Detect Prev 29: 294 –299, 2005. 135. Wu S, Ko YS, Teng MS, Ko YL, Hsu LA, Hsueh C, Chou YY, Liew CC, Lee YS. Adriamycin-induced cardiomyocyte and endothelial cell apoptosis: in vitro and in vivo studies. J Mol Cell Cardiol 34: 1595–1607, 2002. 136. Xie L, Terrand J, Xu B, Tsaprailis G, Boyer J, Chen QM. Cystatin C increases in cardiac injury: a role in extracellular matrix protein modulation. Cardiovasc Res 87: 628 –635, 2010. 137. Xu Y, Liu Z, Sun J, Pan Q, Sun F, Yan Z, Hu X. Schisandrin B prevents doxorubicin-induced chronic cardiotoxicity and enhances its anticancer activity in vivo. PLoS One 6: e28335, 2011. 138. Yagci-Kupeli B, Varan A, Yorgun H, Kaya B, Buyukpamukcu M. Tissue Doppler and myocardial deformation imaging to detect myocardial dysfunction in pediatric cancer patients treated with high doses of anthracyclines. Asia Pac J Clin Oncol 8: 368 –374, 2012. 139. Yamac D, Elmas C, Ozogul C, Keskil Z, Dursun A. Ultrastructural damage in vascular endothelium in rats treated with paclitaxel and doxorubicin. Ultrastruct Pathol 30: 103–110, 2006. 140. Zerra P, Cochran TR, Franco VI, Lipshultz SE. An expert opinion on pharmacologic approaches to reducing the cardiotoxicity of childhood acute lymphoblastic leukemia therapies. Expert Opin Pharmacother 14: 1497–1513, 2013. 141. Zhang J, Herman EH, Ferrans VJ. Dendritic cells in the hearts of spontaneously hypertensive rats treated with doxorubicin with or without ICRF-187. Am J Pathol 142: 1916 –1926, 1993. 142. Zhang S, Liu X, Bawa-Khalfe T, Lu LS, Lyu YL, Liu LF, Yeh ET. Identification of the molecular basis of doxorubicin-induced cardiotoxicity. Nat Med 18: 1639 –1642, 2012. 143. Zhang Y, Kang YM, Tian C, Zeng Y, Jia LX, Ma X, Du J, Li HH. Overexpression of Nrdp1 in the heart exacerbates doxorubicin-induced cardiac dysfunction in mice. PLoS One 6: e21104, 2011. 144. Zhao X, Zhang J, Tong N, Liao X, Wang E, Li Z, Luo Y, Zuo H. Berberine attenuates doxorubicin-induced cardiotoxicity in mice. J Int Med Res 39: 1720 –1727, 2011. 145. Zhao Y, McLaughlin D, Robinson E, Harvey AP, Hookham MB, Shah AM, McDermott BJ, Grieve DJ. Nox2 NADPH oxidase promotes pathologic cardiac remodeling associated with Doxorubicin chemotherapy. Cancer Res 70: 9287–9297, 2010. 146. Zhou S, Palmeira CM, Wallace KB. Doxorubicin-induced persistent oxidative stress to cardiac myocytes. Toxicol Lett 121: 151–157, 2001. 147. Zhu W, Soonpaa MH, Chen H, Shen W, Payne RM, Liechty EA, Caldwell RL, Shou W, Field LJ. Acute doxorubicin cardiotoxicity is associated with p53-induced inhibition of the mammalian target of rapamycin pathway. Circulation 119: 99 –106, 2009. 148. Zsary A, Szucs S, Keltai K, Pasztor E, Schneider T, Rosta A, Sarman P, Janoskuti L, Fenyvesi T, Karadi I. Endothelin-1 and cardiac function in anthracycline-treated patients: a 1-year follow-up. J Cardiovasc Pharmacol 44, Suppl 1: S372–S375, 2004.

AJP-Heart Circ Physiol • doi:10.1152/ajpheart.00099.2014 • www.ajpheart.org