Search Results

You are looking at 1 - 2 of 2 items for

  • Author: M Roudbaraki x
  • Refine by access: All content x
Clear All Modify Search
L Lemonnier
Search for other papers by L Lemonnier in
Google Scholar
PubMed
Close
,
R Lazarenko
Search for other papers by R Lazarenko in
Google Scholar
PubMed
Close
,
Y Shuba
Search for other papers by Y Shuba in
Google Scholar
PubMed
Close
,
S Thebault
Search for other papers by S Thebault in
Google Scholar
PubMed
Close
,
M Roudbaraki
Search for other papers by M Roudbaraki in
Google Scholar
PubMed
Close
,
G Lepage
Search for other papers by G Lepage in
Google Scholar
PubMed
Close
,
N Prevarskaya
Search for other papers by N Prevarskaya in
Google Scholar
PubMed
Close
, and
R Skryma
Search for other papers by R Skryma in
Google Scholar
PubMed
Close

Neuroendocrine (NE) differentiation of prostate epithelial/basal cells is a hallmark of advanced, androgen-independent prostate cancer, for which there is no successful therapy. Here we report for the first time on alterations in regulatory volume decrease (RVD) and its key determinant, swelling-activated Cl current (ICl,swell), associated with NE differentiation of androgen-dependent LNCaP prostate cancer epithelial cells. NE-differentiating regimens, namely, chronic cAMP elevation or androgen deprivation, resulted in generally augmented ICl,swell and enhanced RVD. This occurred as a result of both the increased endogenous expression of ClC-3, which is a volume-sensitive Cl channel involved, as we show, in ICl,swell in LNCaP (lymph-node carcinoma of the prostate) cells and the weaker negative ICl,swell control from Ca2+entering via store-dependent pathways. The changes in the RVD of NE-differentiated cells generally mimicked those reported for Bcl-2-conferred apoptotic resistance. Our results suggest that strengthening the mechanism that helps to maintain volume constancy may contribute to better survival rates of apoptosis-resistant NE cells.

Free access
G Bidaux
Search for other papers by G Bidaux in
Google Scholar
PubMed
Close
,
M Roudbaraki
Search for other papers by M Roudbaraki in
Google Scholar
PubMed
Close
,
C Merle
Search for other papers by C Merle in
Google Scholar
PubMed
Close
,
A Crépin
Search for other papers by A Crépin in
Google Scholar
PubMed
Close
,
P Delcourt
Search for other papers by P Delcourt in
Google Scholar
PubMed
Close
,
C Slomianny
Search for other papers by C Slomianny in
Google Scholar
PubMed
Close
,
S Thebault
Search for other papers by S Thebault in
Google Scholar
PubMed
Close
,
J-L Bonnal
Search for other papers by J-L Bonnal in
Google Scholar
PubMed
Close
,
M Benahmed
Search for other papers by M Benahmed in
Google Scholar
PubMed
Close
,
F Cabon
Search for other papers by F Cabon in
Google Scholar
PubMed
Close
,
B Mauroy
Search for other papers by B Mauroy in
Google Scholar
PubMed
Close
, and
N Prevarskaya
Search for other papers by N Prevarskaya in
Google Scholar
PubMed
Close

TRPM8 (melastatine-related transient receptor potential member 8), a member of the transient receptor potential (TRP) superfamily of cation channels, has been shown to be a calcium-channel protein. TRPM8 mRNA has also been shown to be overexpressed in prostate cancer and is considered to play an important role in prostate physiology. This study was designed to determine the androgen-regulation mechanisms for TRPM8 mRNA expression and to identify the phenotype of TRPM8-expressing cells in the human prostate. Our findings show that trpm8 gene expression requires a functional androgen receptor. Furthermore, this article argues strongly in favour of the fact that the trpm8 gene is a primary androgen-responsive gene. Single-cell reverse transcriptase PCR and immunohistochemical experiments also showed that the trpm8 gene was mainly expressed in the apical secretory epithelial cells of the human prostate and trpm8 down-regulation occurred during the loss of the apical differentiated phenotype of the primary cultured human prostate epithelial cells. The androgen-regulated trpm8 expression mechanisms are important in understanding the progression of prostate cancer to androgen-independence. These findings may contribute to design a strategy to predict prostate cancer status from the TRPM8 mRNA level. Furthermore, as the TRPM8 channel is localized in human prostate cells, it will be interesting to understand its physiological function in the normal prostate and its potential role in prostate cancer development.

Free access