Apoptosis in prostate cancer: bax correlation with stage.
BACKGROUND
Dysregulation of apoptosis may contribute to the process of prostate tumorigenesis by reducing the rate of cell death. Bcl-2 and bax are important molecules involved in the regulation of apoptosis. The aim of the present study is to examine apoptosis and related regulatory molecular markers in a group of Iranian patients with prostate cancer.


METHODS
Paraffin-embedded tissues from 50 patients of prostate carcinoma were examined for the expression of bcl-2 antiapoptotic and bax proapoptotic markers and also proliferation marker, Ki-67, by immunohistochemistry. Detection of apoptotic cells was performed using TUNEL method. Correlation between apoptotic index, proliferation index and bcl-2 and bax expression with stage, pathological grade and Gleason score was determined.


RESULTS
Apoptosis was detected in 12% of prostate cancers. No correlation was observed between apoptosis and differentiation status of carcinoma. Bcl-2 expression was detected in 21 of samples. A significant correlation between bcl-2 expression and Ki-67 staining index (r = 0.349, P = 0.012) was observed. High bax protein expression was shown in our study. We found a significant correlation between bax expression and stage of carcinoma (r = 0.388, P = 0.031), but not with the apoptosis index, suggesting the presence of a non-functional bax protein or the role of other proapoptotic molecules.


CONCLUSIONS
The patients in the present study showed a different pattern of apoptosis positivity compared to other reports. Bax expression may be a useful marker for prognosis of prostate cancer.
Amirghofran
Zahra
Z
Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran.
Monabati
Ahmad
A
Gholijani
Nasser
N
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000378:metabolism; D001706:Biopsy; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000096:biosynthesis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis* / Q000276:immunology; D051028:bcl-2-Associated X Protein
D000911:Antibodies, Monoclonal; C494826:BAX protein, human; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein