Expression of p53 and apoptosis in prostatic adenocarcinoma

초록

INTRODUCTION : Mutation of p53 gene is one of the most common genetic abnormalities found in solid human tumor. p53 gene is related to the cell cycle and concerned with the control of cellular proliferation or cell death by mediating programmed cell death (Apoptnsis). Either increased cellular proliferation or decreased cell death might result in an expansion of their numbers in the uncogenic process. Overexpression of p53 gene indicating an alteration of the pfi'J tumor-suppressor gene and defect in apoptosis have been described as the development of cancer. MATERIAL AND METHOD : To investigate the expression of p53 gene and apoptosis in the metastatic adenocarcinoma of the prostate, we examined 31 paraffin-embedded tissues by immunohistochemical technique and compared with tumor grade, survival estimate Nuclear expression of p53 could be detected using the monoclononal antibody DO-7 and the expression of apoptosis could be detected using the Apotag by in situ hybridization. The study group was divided by Gleason sum score into low score (score 2-7. 16 cases) and high score (score 8-10, 15 cases). RESULT Positive staining for p53 was Sound in three of sixteen low score group(19%). eight of fifteen high grade group(53%). Difruse(>2096) staining was considered as positive for p53 expression. Positive expression of p53 showed more frequent in high Gleason score group than in low score group(p=0.044). And more expression for p53 was related to more short survival time than negative p53 group(p=0.041). Mean expression for apoptosis in thirty one cases was 32%. In low Gleason score group mean expression for apoptosis was 35% and 28% was found in high Gleason score group. No significant relationship between low and high group expression for apoptosis(p=0.2526). No difference was found for survival time between two group(p=0.%) And no specific relationship was found between the expression of p53 and apoptosis in low and high Gleason score group each other(p=0.275). CONCLUSION : These results suggest that p53 mutations play an important role in the acquisition of aggressive biological properties in the metastatic prostate cancer in relation to (lleason grade. Therefore we might use the extent of p53 expression as an usuful piognositic. factor in clinical aspects. But the expression of apoptosis can not reveal any specific features with tumor grade, survival time. So apoptosis can not have implications for predicting the heterogeneity of prostate cancer befor antiandrgen therapy.