International Journal of Biotechnology and Biochemistry. ISSN 0973-2691 Volume 8, Number 2 (2012) pp. 61-69 © Research India Publications http://www.ripublication.com/ijbb.htm
Increasing Evidence for Cigarette Smoking and Prostate Cancer Progression in Eastern Nigera Maxwell Omabe1*, Chinwe Ewenighi1, J.C. Onyeanusi1, Nnatuanya1, I.N. Onoh L.U.M., Ezugwu Uchechukwu A.3, Martin Ezeani2 Ogbonnaya Kenneth1, Uzor Simon1 and Okike Omabe1 1
Department of Medical Laboratory Sciences, Faculty of Health Science and Technology, Ebonyi State University 2 Department of Neurosciences, University of Susex, United Kingdom 3 Department of Physiotherapy, University of Nigeria Teaching Hospital, Enugu. *Corresponding Author E-mail:
[email protected]
Abstract Prostate cancer is the leading cause of death among cigarette smokers in the developing nations especially, in African countries. Evidence from our study showed that prostate cancer is the second leading cause of cancer in men especially those who smoke cigarette. Age, diet, ethnicity, environment and genetic inheritance, are known risk factors for prostate cancer. The aim of this study is to determine the effect of cigarette smoking on the physiology of the prostate gland and to access the level of biomarkers of prostate neoplasm in the smokers and their age match controls. The study was divided into two groups; the first group involved healthy adult smokers and their age-matched non smokers. The second stage of the study was done to confirm the result of the first stage as above. This involves cohort of patients with prostate disease who were smokers and non smokers. Serum levels of PSA, total acid phosphatase, prostate specific acid phosphatase were analysed using established protocol. Data from our study showed that, from the healthy adult population, smokers had a statistically significant increase serum level of both total and prostate specific acid phosphatase compared to age matched healthy non smokers (p10ng/ml. These grades were defined and interpreted as follows; A 10 ng/ml = the colour intensity was stronger than the reference.
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The category in the group of A was regarded as negative for prostate cancer of its progression. A and B were regarded as positive for prostate cancer. Determination of acid phosphotase Serum level of acid phosphotase were measured and included total and prostate specific acid phosphotase which were determined according to established protocol. P –Nitrophenyl phosphate is hydrolyzed in acid pH medium by the action of acid phosphatase present in serum. The liberated p-Nitrophenol was quantified spectrophotometrically. The tartaric acid acts as inhibitor of the prostatic acid phosphatase. This tartaric -sensitive fraction is measured by the difference in activity observed when the assay is carried out in the absence and presence of tartaric acid. Three test tubes were used for each sample. The test tubes were labeled for e.g BL (for blank), SAI (for total acid phosphatase), and SA2 for prostatic acid phosphatase. 0.5ml of working reagent was pipetted into each of the test tubes. Then I drop of tartaric acid was added to test tube labeled SA2. The test tube labeled BL contains blank solution. They were mixed and incubated at 370 C for approximately 3 minutes. After 3 minutes, 0.1ml of the sample was pipetted into each of the test tubes labeled SAI and SA2. The solutions were mixed again and incubated at 370C for 30 minutes. After this, 5.0 ml of sodium hydroxide (NaOH) was added to each of the test tubes to stop the activity of the enzyme. 0.1ml of the sample was added to the test tube labeled BL. The solutions were mixed and the results were read within the wavelength ranges of (400-420nm). PSA was determined with ELISA method. After the blood was spun, the serum was separated and about 1ml of the serum was used for the experiment. The protocol for measurement was as decribed by the manufacturer of the kit, and include adding the sample to the kit and reading the values according to the directives of in the manual.
Figure 1; the mean serum concentration of total acid phosphatase level of healthy adult smokers and non age matched smokers. *** = P < 0.0001. Data shows that smoking may increase the risk of prostatic disease in healthy eastern Nigerian adults.
Serum prostatic acid phosphatase level in U/L
Increasing Evidence for Cigarette Smoking and Prostate Cancer Progression
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10.0
7.5
5.0
2.5
ok er s sm N on
Sm
ok er s
0.0
Figure 2; the mean serum concentration of prostate specific acid phosphatase level of healthy adult smokers and non age matched smokers. *** = P < 0.0001. Data shows that acid phoshatase was actually released by the prostate gland and confirms that smoking may increase the risk of prostatic disease in healthy eastern Nigerian adults.
Table 1: to confirm the earlier observation above and to verify if the result reflect the clinical scenario among prostate cancer patients. Patients attending Urologic clinic were divided into four groups as shown below. Data show that patients who smoke and have been diagnosed with prostate pathology have more aggressive and progressive disease as indicated by the serum level of PSA. Smokers Smokers positive for PSA negative for PSA Percen 93.75 6.25 tage
Non smokers positive for PSA 9.38
Non smokers negative for PSA 90.62
Result and Discussion Smoking is an important risk factor for many cancers. A recent publication has shown that long-term cigarette smoking may be causally associated with breast cancer risk (Cox et al 2011). Previous studies that examined the relationship between cigarette use and prostatic cancer disease incidence yielded inconsistent results or conflicting results, although most studies have suggested that smoking is related to the occurrence of fatal prostate cancer (catalona et al., 1994). We have shown that cigarette smoking was associated with increased level of serum prostate specific acid phosphatase in healthy young adult population in Eastern Nigeria (figure 1 and 2). Data showed that men aged 20 – 40 years who were smokers had a statistically
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significant increase in both total and prostate specific acid phoshotase activity compared to age matched health non smokers from the same region (p
