Expression analysis of caspase-6, caspase-9 and BNIP3 in prostate cancer.
OBJECTIVE
Altered regulation of cell death is a feature of human cancer. The aim of this study was to explore whether the expression of the proapoptotic proteins caspase-6, caspase-9, and Bcl-2/adenovirus E1B-19kDa-interacting protein3 (BNIP3) is altered in prostate cancers.


METHODS
We analyzed the expression of caspase-6, caspase-9, and BNIP3 in 107 prostate adenocarcinoma tissues by immunohistochemistry using a tissue microarray (TMA) method.


RESULTS
Normal glandular cells expressed caspase-6 and BNIP3 proteins in 10 (9.3%) and 9 (8.4%) prostate tissues, respectively. By contrast, the prostate cancers expressed caspase-6 and BNIP3 in 65 (60.7%) and 69 (64.5%) cases, respectively. Prostate intraepithelial neoplasia (PIN) showed caspase-6 and BNIP3 expression in 65% and 65% of cases, respectively. We observed caspase-9 expression in 40 (37.4%) normal, 8 (40%) PIN, and 45 (42.1%) cancer tissues. None of the expression of caspase-6, caspase-9 or BNIP3 was associated with pathological characteristics such as tumor size, patient age, Gleason score, or tumor stage.


CONCLUSIONS
Our data showed that prostate cancer and PIN cells display higher expression of the proapoptotic proteins caspase-6 and BNIP3 than normal cells. Neo-expression of these proteins from the PIN stage suggests that apoptosis deregulation might occur in the early stage of prostate carcinogenesis, and that altered expression of proapoptotic proteins may be a feature of prostate cancer.
Yoo
Nam Jin
NJ
Department of Pathology, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Kim
Min Seob
MS
Park
Sang Wook
SW
Seo
Seong Il
SI
Song
Sang Yong
SY
Lee
Ji Youl
JY
Lee
Sug Hyung
SH
D000230:Adenocarcinoma / Q000737:chemistry* / Q000201:enzymology / Q000473:pathology; D000328:Adult; D000368:Aged; D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000032:analysis*; D053178:Caspase 6 / Q000032:analysis*; D053453:Caspase 9 / Q000032:analysis*; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins / Q000032:analysis*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D011471:Prostatic Neoplasms / Q000737:chemistry* / Q000201:enzymology / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000032:analysis*
C090121:BNIP3 protein, human; D014408:Biomarkers, Tumor; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D053178:Caspase 6; D053453:Caspase 9