Chen-Pang Hou1, Ke-Hung Tsui2, Kang-Shuo Chang3, Hsin-Ching Sung4, Shu-Yuan Hsu4, Yu-Hsiang Lin5, Pei-Shan Yang5, Chien-Lun Chen5, Tsui-Hsia Feng6, Horng-Heng Juang7. 1. Department of Urology, Chang Gung Memorial Hospital at Linkou, Kweishan, Taoyuan, Taiwan; Graduate Institute of Clinical Medical Science, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. 2. Department of Urology, Shuang Ho Hospital, New Taipei City, Taiwan; Department of Medicine; TMU Research Center of Urology and Kindey, College of Medicine, Taipei Medical University, Taipei, Taiwan. 3. Department of Anatomy, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. 4. Department of Anatomy, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. 5. Department of Urology, Chang Gung Memorial Hospital at Linkou, Kweishan, Taoyuan, Taiwan. 6. Department of Anatomy, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan; School of Nursing, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. 7. Department of Urology, Chang Gung Memorial Hospital at Linkou, Kweishan, Taoyuan, Taiwan; Department of Anatomy, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. Electronic address: hhj143@mail.cgu.edu.tw.
Abstract
BACKGROUND: Caffeic acid phenethyl ester (CAPE), a bioactive component of propolis, has beneficial effects on cancer prevention. Growth differentiation factor 15 (GDF15) is an antitumor gene of bladder cancer. Therefore, this study investigated the anti-cancer effect of CAPE on bladder carcinoma cells and related mechanisms. METHODS: The expressions of GDF15, N-myc downstream-regulated gene 1 (NDRG1), and maspin, and the activations of extracellular signal regulated kinase (ERK), c-jun Nterminal kinase (JNK), p38, and 50 adenosine monophosphate-activated protein kinase (AMPK) α1/2 in human bladder cells after gene transfection or knockdown were determined by immunoblot, real-time reverse transcriptase-polymerase chain reaction (RT-qPCR), and reporter assays. The assays of 5-ethynyl-2'-deoxyuridine (EdU), CyQUANT cell proliferation, and Matrigel invasion, and the xenograft animal study were used to assess the cell proliferation, invasion, and tumorigenesis. RESULTS: GDF15 expression in epithelial cells was negatively correlated with neoplasia in vitro. Also, GDF15 exhibits in bladder fibroblasts and smooth muscle cells. CAPE-induced expressions of NDRG1 and maspin decreased cell proliferation and invasion of bladder carcinoma cells in a GDF15-dependent manner in vitro. The xenograft animal study suggesting CAPE attenuated tumor growth in vivo. CAPE increased phosphorylation of ERK, JNK, p38, and AMPKα1/2 to modulate the GDF15 expressions. Pretreatments with ERK, JNK, or p38 inhibitors partially inhibited the CAPE effects on the inductions of GDF15, NDRG1, or maspin. Knockdown of AMPKα1/2 attenuated the CAPE-induced GDF15 expression and cell proliferation in bladder carcinoma cells. CONCLUSIONS: Our findings indicate that CAPE is a promising agent for anti-tumor growth in human bladder carcinoma cells via the upregulation of GDF15.
BACKGROUND: Caffeic acid phenethyl ester (CAPE), a bioactive component of propolis, has beneficial effects on cancer prevention. Growth differentiation factor 15 (GDF15) is an antitumor gene of bladder cancer. Therefore, this study investigated the anti-cancer effect of CAPE on bladder carcinoma cells and related mechanisms. METHODS: The expressions of GDF15, N-myc downstream-regulated gene 1 (NDRG1), and maspin, and the activations of extracellular signal regulated kinase (ERK), c-jun Nterminal kinase (JNK), p38, and 50 adenosine monophosphate-activated protein kinase (AMPK) α1/2 in human bladder cells after gene transfection or knockdown were determined by immunoblot, real-time reverse transcriptase-polymerase chain reaction (RT-qPCR), and reporter assays. The assays of 5-ethynyl-2'-deoxyuridine (EdU), CyQUANT cell proliferation, and Matrigel invasion, and the xenograft animal study were used to assess the cell proliferation, invasion, and tumorigenesis. RESULTS: GDF15 expression in epithelial cells was negatively correlated with neoplasia in vitro. Also, GDF15 exhibits in bladder fibroblasts and smooth muscle cells. CAPE-induced expressions of NDRG1 and maspin decreased cell proliferation and invasion of bladder carcinoma cells in a GDF15-dependent manner in vitro. The xenograft animal study suggesting CAPE attenuated tumor growth in vivo. CAPE increased phosphorylation of ERK, JNK, p38, and AMPKα1/2 to modulate the GDF15 expressions. Pretreatments with ERK, JNK, or p38 inhibitors partially inhibited the CAPE effects on the inductions of GDF15, NDRG1, or maspin. Knockdown of AMPKα1/2 attenuated the CAPE-induced GDF15 expression and cell proliferation in bladder carcinoma cells. CONCLUSIONS: Our findings indicate that CAPE is a promising agent for anti-tumor growth in human bladder carcinoma cells via the upregulation of GDF15.