Format

Send to

Choose Destination

TNF-alpha protects dendritic cells from prostate cancer-induced apoptosis.

Author information

1
Department of Urology, University of Pittsburgh Medical Center, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.

Abstract

We have recently shown that human prostate cancer (PCa) cells induced apoptotic death of the most potent antigen-presenting cells, dendritic cells (DC), which are responsible for the induction of specific antitumor immune responses. Here we have evaluated the effect of murine PCa cells RM-1 on the survival of immature and tumor necrosis factor-alpha (TNF-alpha)-stimulated mature DC. PCa cells and DC were co-incubated for 24-48 h and DC apoptosis was assessed by morphologic criteria, Annexin V assay, and TUNEL staining. We have shown that co-incubation of RM-1 cells with DC is accompanied by an increased level of DC apoptosis, which was mediated by decreased expression of anti-apoptotic protein Bcl-2. Stimulation of DC maturation by TNF-alpha resulted in increased resistance of DC to PCa-induced apoptosis. In TNF-alpha treated mature DC, but not in immature DC, the expression of Bcl-2 was not blocked after exposure to RM-1-derived factors. Thus, these data suggest that TNF-alpha-induced maturation of DC increases their resistance to PCa induced apoptosis. This is likely to be due to the stabilizing of the expression of anti-apoptotic protein Bcl-2. The difference in the sensitivity of mature and immature DC to PCa-induced cell death should be considered during the design of DC-based clinical trials for PCa patients.Prostate Cancer and Prostatic Diseases (2001) 4, 221-227.

PMID:
12497022
DOI:
10.1038/sj.pcan.4500525
Free full text

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center