Xueting Ye1, Jing Xie2, Hang Huang1, Zhexian Deng1. 1. Department of Urology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. 2. Department of Stomatology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Abstract
BACKGROUND/AIMS: Melanoma antigen A6 (MAGEA6) is a cancer-specific ubiquitin ligase of AMP-activated protein kinase (AMPK). The current study tested MAGEA6 expression and potential function in renal cell carcinoma (RCC). METHODS: MAGEA6 and AMPK expression in human RCC tissues and RCC cells were tested by Western blotting assay and qRT-PCR assay. shRNA method was applied to knockdown MAGEA6 in human RCC cells. Cell survival and proliferation were tested by MTT assay and BrdU ELISA assay, respectively. Cell apoptosis was tested by the TUNEL assay and single strand DNA ELISA assay. The 786-O xenograft in nude mouse model was established to test RCC cell growth in vivo. RESULTS: MAGEA6 is specifically expressed in RCC tissues as well as in the established (786-O and A498) and primary human RCC cells. MAGEA6 expression is correlated with AMPKα1 downregulation in RCC tissues and cells. It is not detected in normal renal tissues nor in the HK-2 renal epithelial cells. MAGEA6 knockdown by targeted-shRNA induced AMPK stabilization and activation, which led to mTOR complex 1 (mTORC1) in-activation and RCC cell death/apoptosis. AMPK inhibition, by AMPKα1 shRNA or the dominant negative AMPKα1 (T172A), almost reversed MAGEA6 knockdown-induced RCC cell apoptosis. Conversely, expression of the constitutive-active AMPKα1 (T172D) mimicked the actions by MAGEA6 shRNA. In vivo, MAGEA6 shRNA-bearing 786-O tumors grew significantly slower in nude mice than the control tumors. AMPKα1 stabilization and activation as well as mTORC1 in-activation were detected in MAGEA6 shRNA tumor tissues. CONCLUSION: MAGEA6 knockdown inhibits human RCC cells via activating AMPK signaling.
BACKGROUND/AIMS: Melanoma antigen A6 (MAGEA6) is a cancer-specific ubiquitin ligase of AMP-activated protein kinase (AMPK). The current study tested MAGEA6 expression and potential function in renal cell carcinoma (RCC). METHODS:MAGEA6 and AMPK expression in humanRCC tissues and RCC cells were tested by Western blotting assay and qRT-PCR assay. shRNA method was applied to knockdown MAGEA6 in humanRCC cells. Cell survival and proliferation were tested by MTT assay and BrdU ELISA assay, respectively. Cell apoptosis was tested by the TUNEL assay and single strand DNA ELISA assay. The 786-O xenograft in nude mouse model was established to test RCC cell growth in vivo. RESULTS:MAGEA6 is specifically expressed in RCC tissues as well as in the established (786-O and A498) and primary humanRCC cells. MAGEA6 expression is correlated with AMPKα1 downregulation in RCC tissues and cells. It is not detected in normal renal tissues nor in the HK-2 renal epithelial cells. MAGEA6 knockdown by targeted-shRNA induced AMPK stabilization and activation, which led to mTOR complex 1 (mTORC1) in-activation and RCC cell death/apoptosis. AMPK inhibition, by AMPKα1 shRNA or the dominant negative AMPKα1 (T172A), almost reversed MAGEA6 knockdown-induced RCC cell apoptosis. Conversely, expression of the constitutive-active AMPKα1 (T172D) mimicked the actions by MAGEA6 shRNA. In vivo, MAGEA6 shRNA-bearing 786-O tumors grew significantly slower in nude mice than the control tumors. AMPKα1 stabilization and activation as well as mTORC1 in-activation were detected in MAGEA6 shRNA tumor tissues. CONCLUSION:MAGEA6 knockdown inhibits humanRCC cells via activating AMPK signaling.
Authors: Rebecca R Florke Gee; Helen Chen; Anna K Lee; Christina A Daly; Benjamin A Wilander; Klementina Fon Tacer; Patrick Ryan Potts Journal: J Biol Chem Date: 2020-09-13 Impact factor: 5.157
Authors: Aaron Chen; Alexis L Santana; Nicole Doudican; Nazanin Roudiani; Kristian Laursen; Jean-Philippe Therrien; James Lee; Diane Felsen; John A Carucci Journal: PLoS One Date: 2020-11-23 Impact factor: 3.240
Authors: Chifei Kang; Ran Rostoker; Sarit Ben-Shumel; Rola Rashed; James Andrew Duty; Deniz Demircioglu; Irini M Antoniou; Lika Isakov; Zila Shen-Orr; Jose Javier Bravo-Cordero; Nathan Kase; Math P Cuajungco; Thomas M Moran; Derek LeRoith; Emily Jane Gallagher Journal: Cells Date: 2021-12-06 Impact factor: 7.666