Role of Bcl-2 immuno-reactivity in prostate malignant tumors

Abstract

Introduction:

Prostate cancer is the most common occurring cancer in Sudanese men. Bcl-2 is an anti- apoptotic oncoprotein. Elevated levels of Bcl-2 protein may contribute to the progression of prostate cancers to a metastatic and hormone-insensitive state characterized by poor responses to chemotherapy. Thus the aim of this study is to analyze Bcl-2 expression in prostate adenocarcinoma and its association with prostate cancer grade. Materials and methods:

This was a retrospective case control study conducted in faculty of medical laboratory sciences, Al-Neelain University. The samples were paraffin embedded tissue blocks collected from Rahma Medical Lab during the year 2019. The study included the samples of 40 patients diagnosed with prostate adenocarcinoma and 40 samples from patients diagnosed with prostate hyperplasia used as controls. The expression of Bcl-2 protein was tested using immunohistochemistry technique by tissue microarray . Then the percentage of expression based on staining intensity was given scores: 0, 1−, 1+, 2+, and 3+. Then data was analysed using SPSS and GraphPad computer programs.

Results:

The age of the patients ranged between 59- 70 years with mean age of 67.25 years. The age range of the control samples was between 50-71 years and their mean age was 61.58 years. For the case group; 33 (82.5%) were from Khartoum, 3 (7.5%) from Dungula, 2 (5%) from Mdani and 2 (5%) from Nahr Elnil. For the controls; 34 (85%) were from Khartoum, 3 (7.5%) from Dungula, 2 (5%) from Madani and 1 (2.5%) were from Al-Nil Alabyad. Based on Gleason grading system; prostate adenocarcinoma was represented with different grades; grade 1 were 21 samples (52.5%), grade 2 were 4 samples (10%), grade 3 were 3 samples (7.5%), grade 4 were 7 samples (17.5%) and grade 5 were 5 samples (12.5%). In the case group, Bcl-2 was expressed in 4 samples (10%) and negative in the rest of the 36 (90%) of the samples. For the control samples none showed any degree of Bcl-2 marker expressions. The P. value was 0.1156, OR=0 and 95% CI was 0-09144. The expression of the marker in the four samples was weak in 3 (+1) which were diagnosed with adenocarcinoma grade 1 and grade 2 and moderate (+2) in 1 sample which was adenocarcinoma grade 3.

Discussion:

The mean age of case and control groups were similar to the international mean age of patients diagnosed with prostate adenocarcinoma and benign prostatic hyperplasia. The majority of the cases and controls were from Khartoum. This could be either due to relocation of patient for treatment purposes or the data is affected by the fact that Khartoum is the centre of cancer care. The dominating cancer grade was grade 1 and this could be due to the annoying signs of prostate enlargement. Bcl-2 expression has insignificant association with prostate adenocarcinoma.