Apoptosis-related gene expression in benign prostatic hyperplasia and prostate carcinoma

Background: The aim of this study was to examine the expressions of the bcl-2, bax, fas and c-myc apoptosis-related genes in benign prostatic hyperplasia (BPH) and prostate carcinoma (CaP) to determine whether significant differences exist within each disease and between the two groups of patients. The correlation between gene expression and tumour diameter, stage, Gleason score and serum PSA was also investigated. Patients and methods: Tissue specimens from 51 cases of BPH and 27 cases of CaP were examined for bcl-2, bax, fas and c-myc expression by reverse transcriptase-PCR (RT-PCR). Results: In BPH, bcl-2 and bax gave the weakest signals (p < 0.001). In CaP, bcl-2 was the least expressed gene (p < 0.001). In both patient groups, fas and c-myc were the most highly expressed genes (p < 0.05). Both bcl-2 and bax were expressed at higher levels in CaP than in BPH (p < 0.02). The bcl-2/bax ratio was lower in CaP than in BPH (p < 0.001). Bcl-2 was more highly expressed in high Gleason grade (> 7) tumours (p < 0.05). In the BPH group, bax showed a positive relationship with fas (p < 0.01), while the bcl-2 level inversely correlated with that of c-myc (p < 0.05). Conclusion: Our data showed that all the apoptosis-related genes were expressed in both BPH and CaP. The stronger expression of bax and the lower bcl-2/bax ratio observed in CaP may suggest a pro-apoptotic stimulus, while the higher bcl-2 levels appear to counterbalance the tendency to cell death.