TY - JOUR
T1 - Celastrol blocks interleukin-6 gene expression via downregulation of NF-κB in prostate carcinoma cells
AU - Chiang, Kun Chun
AU - Tsui, Ke Hung
AU - Chung, Li Chuan
AU - Yeh, Chun Nan
AU - Chen, Wen Tsung
AU - Chang, Phei Lang
AU - Juang, Horng Heng
PY - 2014/3/24
Y1 - 2014/3/24
N2 - Interleukin-6 (IL-6), a multifunctional cytokine, contributes to proliferation or differentiation of prostate carcinoma cells in a highly cell type-specific manner. Celastrol (3-hydroxy-24-nor-2oxo-1(10),3,5,7- friedelatetrane-29-oic acid), also named as tripterine, is extracted from root of Chinese traditional herb Tripterygiumwilfordii Hook f with potent anti-inflammatory and anti-cancer activities. In this study, we evaluated the molecular mechanisms of celastrol on cell proliferation and IL-6 gene expression in prostate carcinoma cells. 3H-thymidine incorporation and flow cytometric analysis indicated that celastrol treatments arrested the cell cycle at the G0/G1 phase, thus attenuating cell proliferation in prostate carcinoma PC-3 cells; moreover, celastrol induced cell apoptosis at higher dosage. Knockdown of IL-6 attenuated the anti-proliferative effect of celastrol on PC-3 cells. Results from ELISA and 5′-deletion transient gene expression assays indicated that celastrol treatment decreased IL-6 secretion and gene expression, and this effect is dependent on the NF-κB response element within IL-6 promoter area since mutation of the NF-κB response element from AAATGTCCCATTTTCCC to AAATGTTACATTTTCCC by site-directed mutagenesis abolished the inhibition of celastrol on the IL-6 promoter activity. Celastrol also attenuated the activation of PMA and TNFα on the gene expression and secretion of IL-6 in PC-3 cells. Immunoblot assays revealed that celastrol treatment downregulated the expressions of IKKα, p50 and p65, supporting the 5′-deletion transient gene expression assay result that celastrol blocked IL-6 expression through the NF-κB pathway in PC-3 cells. For the first time, our results concluded that celastrol attenuates PC-3 cell proliferation via downregulation of IL-6 gene expression through the NF-κB-dependent pathway.
AB - Interleukin-6 (IL-6), a multifunctional cytokine, contributes to proliferation or differentiation of prostate carcinoma cells in a highly cell type-specific manner. Celastrol (3-hydroxy-24-nor-2oxo-1(10),3,5,7- friedelatetrane-29-oic acid), also named as tripterine, is extracted from root of Chinese traditional herb Tripterygiumwilfordii Hook f with potent anti-inflammatory and anti-cancer activities. In this study, we evaluated the molecular mechanisms of celastrol on cell proliferation and IL-6 gene expression in prostate carcinoma cells. 3H-thymidine incorporation and flow cytometric analysis indicated that celastrol treatments arrested the cell cycle at the G0/G1 phase, thus attenuating cell proliferation in prostate carcinoma PC-3 cells; moreover, celastrol induced cell apoptosis at higher dosage. Knockdown of IL-6 attenuated the anti-proliferative effect of celastrol on PC-3 cells. Results from ELISA and 5′-deletion transient gene expression assays indicated that celastrol treatment decreased IL-6 secretion and gene expression, and this effect is dependent on the NF-κB response element within IL-6 promoter area since mutation of the NF-κB response element from AAATGTCCCATTTTCCC to AAATGTTACATTTTCCC by site-directed mutagenesis abolished the inhibition of celastrol on the IL-6 promoter activity. Celastrol also attenuated the activation of PMA and TNFα on the gene expression and secretion of IL-6 in PC-3 cells. Immunoblot assays revealed that celastrol treatment downregulated the expressions of IKKα, p50 and p65, supporting the 5′-deletion transient gene expression assay result that celastrol blocked IL-6 expression through the NF-κB pathway in PC-3 cells. For the first time, our results concluded that celastrol attenuates PC-3 cell proliferation via downregulation of IL-6 gene expression through the NF-κB-dependent pathway.
UR - http://www.scopus.com/inward/record.url?scp=84899745281&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0093151
DO - 10.1371/journal.pone.0093151
M3 - 文章
C2 - 24664372
AN - SCOPUS:84899745281
SN - 1932-6203
VL - 9
JO - PLoS ONE
JF - PLoS ONE
IS - 3
M1 - e93151
ER -