Jun-Wei Gai1, Wasilijiang Wahafu2, Ya-Ching Hsieh3, Miao Liu4, Liang Zhang5, Sheng-Wen Li6, Bei Zhang1, Qun He1, Hui Guo7, Jie Jin8. 1. Department of Urology, Peking University First Hospital; Institute of Urology, Peking University, Beijing, China. 2. Department of Urology, China PLA General Hospital, Beijing, China. 3. Department of Anesthesiology and Intensive Care, Peking University First Hospital, Beijing, China. 4. HeDong Center for Disease Control and Prevention, Tianjin, China. 5. Department of Orthopaedic Surgery, Beijing Jishuitan Hospital, Fourth Clinical College of Peking University, Beijing, China. 6. Department of Urology, Tsinghua University First Hospital, Beijing, China. 7. Department of Urology, Tsinghua University First Hospital, Beijing, China. Electronic address: ghduro@yahoo.com. 8. Department of Urology, Peking University First Hospital; Institute of Urology, Peking University, Beijing, China. Electronic address: Jinjie@vip.163.com.
Abstract
OBJECTIVE: Presenilin (PS)/γ-secretase is a key protease that initiates various biological processes. We investigated the effect of PS/γ-secretase on the expression and inhibition of urothelial cell carcinoma of bladder (UCB) as a potential alternative therapeutic target for UCB. MATERIALS AND METHODS: PS-1 and PS-2 were identified in normal and malignant human bladder transitional cells by immunohistochemistry. We blocked PSs using a PS/γ-secretase inhibitor N-(N-[3,5-difluorophenacetyl]-L-alanyl)-S-phenylglycine-t-butylester (DAPT), and the proliferative and invasive potential of UCB cells SW780, BIU-87, 5637, and T24, and human normal urothelial cell line SV-HUC-1 were analyzed using Western blot, cell viability test, flow cytometry, and transwell assay. All experiments were repeated at least 3 times. RESULTS: Human bladder samples of UCB, SW780, BIU-87, 5637, and T24 cells expressed higher PS-1 compared with normal ones. Cell vitality test demonstrated that DAPT attenuated UCB cell proliferation more than SV-HUC-1. Flow cytometry and transwell assay showed that T24 cells were arrested at G1/S checkpoint and its invasive ability was impaired. Western blot assay markedly showed that protein levels of CD44-intracellular domain, insulinlike growth factor-1Rβ, extracellular regulated protein kinase 1/2, cyclin D1, proliferating cell nuclear antigen, and matrix metalloproteinase-9 were downregulated by DAPT, whereas vascular endothelial growth factor receptor-2 and vascular endothelial growth factor-165 were upregulated. CONCLUSIONS: Our study revealed that PS-1 might be implicated in the proliferation and invasion of UCB, and that it may serve as a potential therapeutic target for UCB, but further studies are warranted to verify the effects of inhibition of PS/γ-secretase on angiogenesis.
OBJECTIVE: Presenilin (PS)/γ-secretase is a key protease that initiates various biological processes. We investigated the effect of PS/γ-secretase on the expression and inhibition of urothelial cell carcinoma of bladder (UCB) as a potential alternative therapeutic target for UCB. MATERIALS AND METHODS: PS-1 and PS-2 were identified in normal and malignant human bladder transitional cells by immunohistochemistry. We blocked PSs using a PS/γ-secretase inhibitor N-(N-[3,5-difluorophenacetyl]-L-alanyl)-S-phenylglycine-t-butylester (DAPT), and the proliferative and invasive potential of UCB cells SW780, BIU-87, 5637, and T24, and human normal urothelial cell line SV-HUC-1 were analyzed using Western blot, cell viability test, flow cytometry, and transwell assay. All experiments were repeated at least 3 times. RESULTS:Human bladder samples of UCB, SW780, BIU-87, 5637, and T24 cells expressed higher PS-1 compared with normal ones. Cell vitality test demonstrated that DAPT attenuated UCB cell proliferation more than SV-HUC-1. Flow cytometry and transwell assay showed that T24 cells were arrested at G1/S checkpoint and its invasive ability was impaired. Western blot assay markedly showed that protein levels of CD44-intracellular domain, insulinlike growth factor-1Rβ, extracellular regulated protein kinase 1/2, cyclin D1, proliferating cell nuclear antigen, and matrix metalloproteinase-9 were downregulated by DAPT, whereas vascular endothelial growth factor receptor-2 and vascular endothelial growth factor-165 were upregulated. CONCLUSIONS: Our study revealed that PS-1 might be implicated in the proliferation and invasion of UCB, and that it may serve as a potential therapeutic target for UCB, but further studies are warranted to verify the effects of inhibition of PS/γ-secretase on angiogenesis.