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Fengshan, Taiwan

Tsui K.-H.,Chang Gung Memorial Hospital | Tsui K.-H.,Bioinformation Center | Tsui K.-H.,Chang Gung University | Chang Y.-L.,Chang Gung University | And 5 more authors.
Prostate | Year: 2012

BACKGROUND Glycoprotein transmembrane nmb (GPNMB) gene was originally identified in osteoblasts and belongs to the pmel-17/nmb family. The function or regulation of GPNMB in the human prostate remains unknown. METHODS The expression of GPNMB in prostate carcinoma cells were determined by real-time reverse transcription-polymerase chain reaction (RT-qPCR) and immunoblot assays. Effects of ectopic GPNMB overexpression on cell proliferation, invasion, and tumorigenesis were determined by 3H-thymidine incorporation, matrigel invasion, soft agar cloning assays, and murine xenograft study. Effects of GPNMB, p53, and androgen on target gene were assessed using RT-PCR, immunoblotting, and transient gene expression assays. RESULTS In vitro analysis using several prostate cell lines suggested that expression of GPNMB may be relevant to the extent of neoplasia. Ectopic overexpression of GPNMB significantly attenuated cell proliferation and invasion and exerted antitumorigenic activity on PC-3 cells in vitro and in vivo. GPNMB overexpression induced the gene expressions of N-myc downstream regulated gene 1 (Ndrg1) and maspin in PC-3 cells. Doxorubicin treatment or transient overexpression of p53 increased GPNMB expression. Androgen (R1881) treatment has a divergent effect on gene expression of prostate-specific antigen (PSA) and GPNMB in LNCaP cells. Androgen treatment enhanced cell proliferation but downregulated GPNMB protein expression in stably overexpressed androgen receptor (AR) CA-HPV-10 cells. CONCLUSIONS Together these results suggest that GPNMB gene is a p53- and androgen-dysregulated gene and should be regarded as an anti-tumor gene for prostate cancer. The enhancement of Ndrg1 and maspin gene expressions may account for the anti-proliferative and anti-invasive function of GPNMB in PC-3 cells. © 2012 Wiley Periodicals, Inc.


Tsui K.-H.,Chang Gung Memorial Hospital | Tsui K.-H.,Bioinformation Center | Tsui K.-H.,Chang Gung University | Chung L.-C.,Chang Gung University | And 5 more authors.
International Journal of Cancer | Year: 2012

Luteolin is a polyphenolic flavone and has antitumor activity for many cancers. The prostate-derived Ets factor (PDEF), a novel epithelium-specific Ets transcription factor, acts as an androgen-independent transcriptional activator of the prostate-specific antigen (PSA) promoter. We determined the antitumor function of luteolin via upregulation of PDEF gene expression in human prostate carcinoma LNCaP cells. Results from flow cytometry and 3H-thymidine incorporation assays revealed that luteolin treatments attenuated cell proliferation and arrested the cell cycle at the G1/S phase. High concentration of luteolin (30 μM) induced cell apoptosis. Immunoblot assays and enzyme linked immunosorbent assay revealed that luteolin treatment upregulated PDEF but downregulated androgen receptor (AR) gene expression, which decreased PSA gene expression in LNCaP cells. Results of immunoblot and transient gene expression assays revealed that luteolin treatments at proapoptosis dosage, enhanced gene expression of PDEF, B-cell translocation gene 2 (BTG2), N-myc downstream regulated gene 1 (NDRG1) and Maspin. Transient gene expression assays indicated that cotransfection of the PDEF expression vector enhanced the promoter activities of the BTG2, NDRG1 and Maspin genes. Stable overexpression of PDEF significantly induced BTG2, NDRG1 and Maspin gene expression, which markedly attenuated in vitro cell proliferation and invasion of LNCaP cells. The modulatory effect of luteolin on BTG2, NDRG1 and Maspin gene expression were attenuated when PDEF was knocked-down. These results suggest that luteolin blocks PSA gene expression by downregulation of AR expression. The enhancement of PDEF expression, which induced BTG2, NDRG1 and Maspin gene expression, could account for the function of luteolin for antiproliferation and anti-invasion in LNCaP cells. Copyright © 2011 UICC.


Tsui K.-H.,Chang Gung Memorial Hospital | Tsui K.-H.,Bioinformation Center | Wang S.-W.,Chang Gung University | Chung L.-C.,Chang Gung University | And 6 more authors.
BioMed Research International | Year: 2013

Interleukin-6, a multifunctional cytokine, contributes to tumor cell proliferation and differentiation. However, the biological mechanisms that are affected by the expression of interleukin-6 in bladder cancer cells remain unclear. We evaluated the effects of interleukin-6 expression in human bladder carcinoma cells in vitro and in vivo. The results of interleukin-6-knockdown experiments in T24 cells and interleukin-6-overexpression experiments in HT1376 cells revealed that interleukin-6 reduced cell proliferation, migration, and invasion in vitro. Xenograft animal studies indicated that the overexpression of interleukin-6 downregulated tumorigenesis of bladder cells and that interleukin-6 knockdown reversed this effect. The results of RT-PCR, immunoblotting, and reporter assays indicated that the overexpression of interleukin-6 upregulated the expression of the mammary serine protease inhibitor (MASPIN), N-myc downstream gene 1 (NDRG1), and KAI1 proteins in HT1376 cells and that interleukin-6 knockdown reduced the expression of these proteins in T24 cells. In addition, results of immunoblotting assays revealed that interleukin-6 modulated epithelial-mesenchymal transitions by upregulating the expression of the E-cadherin, while downregulation N-cadherin and vimentin proteins. Our results suggest that the effects of interleukin-6 on the regulation of epithelial-mesenchymal transitions and the expressions of the MASPIN, NDRG1, and KAI1 genes attribute to the modulation of tumorigenesis in human bladder carcinoma cells. © 2013 Ke-Hung Tsui et al.


Chung L.-C.,Tatung University | Chung L.-C.,Chang Gung University | Tsui K.-H.,Chang Gung Memorial Hospital | Tsui K.-H.,Bioinformation Center | And 7 more authors.
Molecular Nutrition and Food Research | Year: 2011

Scope: Prostate-specific antigen (PSA) is a well-known marker for diagnosing and monitoring prostate cancer. Curcumin, a yellow curry pigment, has been reported to enhance androgen receptor (AR) degradation. We examined the effects of curcumin on increasing PSA expression by hypoxia and prolyl hydroxylase inhibitors, L-mimosine and dimethyloxalylglycine (DMOG), in human prostate carcinoma LNCaP cells. Methods and results: The 3H-thymidine incorporation assay revealed that either L-mimosine or DMOG treatments attenuated cell proliferation. Immunoblot and enzyme-linked immunosorbent assays (ELISA) indicated that both L-mimosine and DMOG have an effect similar to hypoxia, which stabilized hypoxia-inducible factor-1α (HIF-1α) and induced PSA gene expression. The results of the immunoblot and transient gene expression assays indicated that induction of the PSA expression by hypoxia is both HIF-1α- and AR-dependent. Immunoblot assays revealed that a curcumin treatment (10μM) decreased the protein abundance of AR but did not significantly affect the protein levels of HIF-1α and vascular endothelial growth factor, which were induced by hypoxia. ELISA and transient gene expression assays indicated that curcumin blocked the activation of L-mimosine or DMOG treatment on PSA expression. Conclusions: These results indicate that curcumin blocked the enhanced effect of PSA expression by L-mimosine and DMOG that induce hypoxia condition. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Chung L.-C.,Tatung University | Chung L.-C.,Chang Gung University | Tsui K.-H.,Bioinformation Center | Feng T.-H.,Chang Gung University | And 4 more authors.
American Journal of Physiology - Cell Physiology | Year: 2012

L-Mimosine, an iron chelator and a prolyl 4-hydroxylase inhibitor, blocks many cancer cells at the late G1 phase. B-cell translocation gene 2 (Btg2) regulates the G1/S transition phases of the cell cycle. N-myc downstream regulated gene 1 (Ndrg1) is a differentiationinducing gene upregulated by hypoxia. We evaluated the molecular mechanisms of L-mimosine on cell cycle modulation in PC-3 and LNCaP prostate carcinoma cells. The effect of L-mimosine on cell proliferation of prostate carcinoma cells was determined by the [ 3H]thymidine incorporation and flow cytometry assays. L-Mimosine arrested the cell cycle at the G1 phase in PC-3 cells and at the S phase in LNCaP cells, thus attenuating cell proliferation. Immunoblot assays indicated that hypoxia and L-mimosine stabilized hypoxia-inducible factor-1α (HIF-1α) and induced Btg2 and Ndrg1 protein expression, but downregulated protein levels of cyclin A in both PC-3 and LNCaP cells. L-Mimosine treatment decreased cyclin D1 protein in PC-3 cells, but not in LNCaP cells. Dimethyloxalylglycine, a pan-prolyl hydroxylase inhibitor, also induced Btg2 and Ndrg1 protein expression in LNCaP cells. The transient gene expression assay revealed that L-mimosine treatment or cotransfection with HIF-1α expression vector enhanced the promoter activities of Btg2 and Ndrg1 genes. Knockdown of HIF-1α attenuated the increasing protein levels of both Btg2 and Ndrg1 by hypoxia or L-mimosine in LNCaP cells. Our results indicated that hypoxia and L-mimosine modulated Btg2 and Ndrg1 at the transcriptional level, which is dependent on HIF-1α. L-Mimosine enhanced expression of Btg2 and Ndrg1, which attenuated cell proliferation of the PC-3 and LNCaP prostate carcinoma cells. © 2012 the American Physiological Society.

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