TY - JOUR
T1 - Targeting Cancer Stem Cells in Castration-Resistant Prostate Cancer
AU - Yun, Eun Jin
AU - Zhou, Jiancheng
AU - Lin, Chun Jung
AU - Hernandez, Elizabeth
AU - Fazli, Ladan
AU - Gleave, Martin
AU - Hsieh, Jer Tsong
N1 - Publisher Copyright:
© 2015 American Association for Cancer Research.
PY - 2016/2/1
Y1 - 2016/2/1
N2 - Purpose: Clinical evidence suggests increased cancer stem cells (CSCs) in a tumor mass may contribute to the failure of conventional therapies because CSCs seem to be more resistant than differentiated tumor cells. Thus, unveiling the mechanism regulating CSCs and candidate target molecules will provide new strategy to cure the patients. Experimental design: The stem-like cell properties were determined by a prostasphere assay and dye exclusion assay. To find critical stem cell marker and reveal regulation mechanism, basic biochemical and molecular biologic methods, such as quantitative real-time PCR, Western blot, reporter gene assay, and chromatin immunoprecipitation assay, were used. In addition, to determine the effect of combination therapy targeting both CSCs and its progeny, in vitro MTT assay and in vivo xenograft model was used. Results: We demonstrate immortalized normal human prostate epithelial cells, appeared nontumorigenic in vivo, become tumorigenic, and acquire stem cell phenotype after knocking down a tumor suppressor gene. Also, those stem-like cells increase chemoresistance to conventional anticancer reagent. Mechanistically, we unveil that Wnt signaling is a key pathway regulating well-known stem cell marker CD44 by directly interacting to the promoter. Thus, by targeting CSCs using Wnt inhibitors synergistically enhances the efficacy of conventional drugs. Furthermore, the in vivo mouse model bearing xenografts showed a robust inhibition of tumor growth after combination therapy. Conclusions: Overall, this study provides strong evidence of CSC in castration-resistant prostate cancer. This new combination therapy strategy targeting CSC could significantly enhance therapeutic efficacy of current chemotherapy regimen only targeting non-CSC cells.
AB - Purpose: Clinical evidence suggests increased cancer stem cells (CSCs) in a tumor mass may contribute to the failure of conventional therapies because CSCs seem to be more resistant than differentiated tumor cells. Thus, unveiling the mechanism regulating CSCs and candidate target molecules will provide new strategy to cure the patients. Experimental design: The stem-like cell properties were determined by a prostasphere assay and dye exclusion assay. To find critical stem cell marker and reveal regulation mechanism, basic biochemical and molecular biologic methods, such as quantitative real-time PCR, Western blot, reporter gene assay, and chromatin immunoprecipitation assay, were used. In addition, to determine the effect of combination therapy targeting both CSCs and its progeny, in vitro MTT assay and in vivo xenograft model was used. Results: We demonstrate immortalized normal human prostate epithelial cells, appeared nontumorigenic in vivo, become tumorigenic, and acquire stem cell phenotype after knocking down a tumor suppressor gene. Also, those stem-like cells increase chemoresistance to conventional anticancer reagent. Mechanistically, we unveil that Wnt signaling is a key pathway regulating well-known stem cell marker CD44 by directly interacting to the promoter. Thus, by targeting CSCs using Wnt inhibitors synergistically enhances the efficacy of conventional drugs. Furthermore, the in vivo mouse model bearing xenografts showed a robust inhibition of tumor growth after combination therapy. Conclusions: Overall, this study provides strong evidence of CSC in castration-resistant prostate cancer. This new combination therapy strategy targeting CSC could significantly enhance therapeutic efficacy of current chemotherapy regimen only targeting non-CSC cells.
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U2 - 10.1158/1078-0432.CCR-15-0190
DO - 10.1158/1078-0432.CCR-15-0190
M3 - Article
C2 - 26490309
AN - SCOPUS:84959018543
SN - 1078-0432
VL - 22
SP - 670
EP - 679
JO - Clinical Cancer Research
JF - Clinical Cancer Research
IS - 3
ER -