Tumor-suppressive effects of neutral endopeptidase in androgen-independent prostate cancer cells Journal Article


Authors: Dai, J.; Shen, R. Q.; Sumitomo, M.; Goldberg, J. S.; Geng, Y. P.; Navarro, D.; Xu, S.; Koutcher, J. A.; Garzotto, M.; Powell, C T.; Nanus, D. M.
Article Title: Tumor-suppressive effects of neutral endopeptidase in androgen-independent prostate cancer cells
Abstract: Expression of neutral endopeptidase (NEP) 24.11 is diminished in metastatic, androgen-independent prostate cancers (PCs; C, N, Papandreou et al., Nat, Med., 4: 50-57, 1998), To determine the effects on androgen-independent PC cells of overexpressing cell-surface NEP, an inducible tetracycline-regulatory gene expression system was used to stably introduce and express the NEP gene in androgen-independent TSU-Prl cells generating WT-5 cells, which expressed high levels of enzymatically active NEP protein when cultured in the absence of tetracycline, TN12 cells, which contain the identical vectors without the NEP gene and do not express NEP, were used as control. Expression of NEP in WT-5 cells after removal of tetracycline from the media resulted in a > 80% inhibition in cell proliferation over a I-meek period (P < 0.005) compared with control cells. Tumor formation occurred in the prostate glands of orthotopically injected athymic mice killed at 30 days in 4 of 5 mice that mere given injections of 2 x 10(6) WT-5 cells and were fed doxycycline (NEP suppressed), and in ail mice that were given injections of TN12 cells and mere fed with or without doxycycline. In contrast, only I of 5 mouse prostates developed a tumor in mice that were given injections of WT-5 cells and that did not receive doxycycline, Analysis of the mechanisms of NEP-induced growth suppression revealed that NEP expression in WT-5 cells induced a 4-fold increase in the number of PC cells undergoing apoptosis, and increased the expression of p21 tumor suppressor gene protein and the level of unphosphorylated retinoblastoma protein as determined by Western blot, Flow cytometric analysis show that induced NEP expression in WT-5 cells resulted in a G, cell cycle arrest. These data show that NEP can inhibit PC cell growth and tumorigenicity and suggest that NEP has potential as therapy for and rogen-independent PC.
Keywords: carcinoma; receptor; focal adhesion kinase; modulation; expression; messenger-rnas; fetal lung; growth-inhibition; inhibits apoptosis; bombesin-like peptides
Journal Title: Clinical Cancer Research
Volume: 7
Issue: 5
ISSN: 1078-0432
Publisher: American Association for Cancer Research  
Date Published: 2001-05-01
Start Page: 1370
End Page: 1377
Language: English
ACCESSION: WOS:000168768500039
PROVIDER: wos
PUBMED: 11350908
Notes: Article -- Source: Wos
Citation Impact
MSK Authors
  1. Jason A Koutcher
    278 Koutcher
  2. Su Xu
    27 Xu
  3. C Thomas Powell
    36 Powell