An adiponectin paralog protein, CTRP6 decreased the proliferation and invasion activity of oral squamous cell carcinoma cells: possible interaction with laminin receptor pathway
MOLECULAR BIOLOGY REPORTS
Authors: Hano, Kimika; Hatano, Kiichi; Saigo, Chiemi; Kito, Yusuke; Shibata, Toshiyuki; Takeuchi, Tamotsu
Abstract
C1q/tumor necrosis factor-related protein-6 (CTRP6), also known as CTRP6 is identified adiponectin paralog. Although recent studies have revealed that adiponectin has an inhibitory role in carcinogenesis, the role of CTRP6 in carcinogenesis remains unclear. In this study, we found that eukaryotic recombinant CTRP6 protein bound to the cell surface membrane of cultured oral squamous cell carcinoma cells by immunofluorescence staining. Screening of CTRP6 binding protein in expression library followed by co-immunoprecipitation assay revealed that CTRP6 bound to the precursor of laminin receptor. CTRP6 disturbed the binding of laminin to the laminin receptor. Interestingly, the eukaryotic recombinant CTRP6 protein significantly suppressed the proliferation and Matrigel invasion activity of oral squamous cell carcinoma SAS cells in a dose-dependent manner. Moreover, administration of CTRP6 significantly attenuated the growth of SAS cells in xenoplant mice model. Laminin and laminin receptor are known to be overexpressed and promote the tumor growth in OSCC. Combined together, the present findings suggest that CTRP6 could repress progression of oral squamous cell carcinoma cells, putatively through disrupting the laminin-laminin receptor axis.
C1q/TNF-related protein 6 (CTRP6) attenuates renal ischaemia-reperfusion injury through the activation of PI3K/Akt signalling pathway
CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY
Authors: Xiang, Heli; Xue, Wujun; Li, Yang; Zheng, Jin; Ding, Chenguang; Dou, Meng; Wu, Xiaoyan
Abstract
C1q/TNF-related protein 6 (CTRP6) is a member of the CTRP family that has been reported to exhibit a nephroprotective effect. However, the role of CTRP6 in renal ischaemia/reperfusion (I/R) injury (IRI) remains unclear. In the present study, we aimed to explore the protective effect of CTRP6 in renal IRI and the potential mechanism. We found that CTRP6 expression was markedly decreased in the kidneys of mice subjected to I/R and HK-2 cells in response to hypoxia/reoxygenation (H/R) stimulation. Recombinant CTRP6 protein protected against renal I/R injury by the reduction of blood urea nitrogen (BUN) and creatinine levels. The increased production of ROS and malondialdehyde (MDA), as well the decreased activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) caused by H/R induction were mitigated by CTRP6 in HK-2 cells. The caspase-3 activity and apoptotic rate were both decreased in CTRP6-overexpressing HK-2 cells. In addition, we also found that knockdown of CTRP6 aggravated H/R-caused oxidative stress and cell apoptosis in HK-2 cells. Moreover, CTRP6 overexpression enhanced the H/R-stimulated activation of PI3K/Akt pathway in HK-2 cells. Inhibition of PI3K reversed the nephroprotective effects of CTRP6 in HK-2 cells. Taken together, CTRP6 exerted protective effects against H/R-caused oxidative injury in HK-2 cells via activating the PI3K/Akt pathway.