Neuroendocrine cells in human prostate over-express the anti-apoptosis protein survivin.
BACKGROUND
Neuroendocrine (NE) differentiation may be related to the growth and progression of prostate cancer, especially androgen-insensitive tumors. Recently the over-expression of a new anti-apoptosis protein, survivin, has attracted attention for its potential implication in many human cancers. The fact that NE cells in prostate are bcl-2 negative prompted us to investigate if the prostatic NE cells over-express survivin.


METHODS
Double immunohistochemical staining and immunofluorescence of chromogranin A (CgA) and survivin were performed in 57 patients with localized prostate cancer who underwent radical prostatectomy. The terminal deoxynucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end-labeling (TUNEL) method was used for apoptosis detection in three prostate cancer specimens with NE differentiation. The relationship between NE differentiation and clinicopathological characteristics, disease progression as well as patient survival, were analyzed retrospectively.


RESULTS
It was found that NE cells in both benign and malignant prostate tissues over-expressed the anti-apoptosis protein survivin. While apoptosis was detected in non-NE epithelial cells, all NE cells were negative for apoptosis detection. During the period of follow-up, 17 (63%) of 27 patients with NE differentiation had prostate cancer progression, while 12 (40%) of 30 patients without NE differentiation had systemic prostate cancer progression. 10 (37%) of 27 patients with NE differentiation died from prostate cancer during the period of follow up, while 6 (20%) of 30 patients without NE differentiation died from prostate cancer. However, none of these characteristics reached statistical significance, probably because of the small number of cases enrolled.


CONCLUSIONS
This study discovers that all the prostatic NE cells express the new anti-apoptosis protein survivin. This provides a strong molecular basis for the hypothesis that NE cells may endure stressful conditions and escape from apoptosis. While our results suggest a trend of NE differentiation with poorer prognosis, the prognosis implication cannot be concluded due to our small sample size.
Xing
N
N
Department of Urology, Mayo Graduate School, Mayo Foundation, Rochester, Minnesota 55905, USA.
Qian
J
J
Bostwick
D
D
Bergstralh
E
E
Young
C Y
CY
D000368:Aged; D017209:Apoptosis / Q000502:physiology; D014408:Biomarkers, Tumor; D016009:Chi-Square Distribution; D053379:Chromogranin A; D002864:Chromogranins / Q000276:immunology; D018450:Disease Progression; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D051034:Inhibitor of Apoptosis Proteins; D008297:Male; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D009024:Morphogenesis; D009363:Neoplasm Proteins; D009490:Neurosecretory Systems / Q000166:cytology* / Q000473:pathology*; D011379:Prognosis; D011467:Prostate / Q000166:cytology* / Q000473:pathology*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000276:immunology / Q000473:pathology*; D011506:Proteins / Q000032:analysis*; D013234:Stem Cells / Q000166:cytology; D000077022:Survivin
C107489:BIRC5 protein, human; D014408:Biomarkers, Tumor; D053379:Chromogranin A; D002864:Chromogranins; D007074:Immunoglobulin G; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D011506:Proteins; D000077022:Survivin