Expression of Rab8a in Colorectal Cancer and Its Effect on the Proliferation and Migration of Cancer Cells

WANG Yongxia^1,2, WANG Beixi^1,2,³, WANG Jianqiang², QIAN Xinlai^1,2*

(¹Department of Pathology, School of Basic Medical Sciences, Xinxiang Medical University; Xinxiang 453003, China; ²Department of Pathology, Third Affiliated Hospital of Xinxiang Medical University; Xinxiang 453000, China; ³Department of Pathology, Fourth Affiliated Hospital of Xinxiang Medical University; Xinxiang 453099, China)

Abstract:

Rab8a is one of the members of Ras small GTPase superfamily and studies have shown it is the contributing element in the development of endometrial cancer and hepatocellular carcinoma. However, the expression and biological function of Rab8a in CRC (colorectal cancer) remain unclear. The expression of Rab8a was firstly analyzed in some malignant tumors including colon and rectal adenocarcinoma by GEPIA (gene expression profiling interactive analysis) in this study and it was found that the expression of Rab8a in the malignant tumors including colon and rectal adenocarcinoma were significantly higher than those in normal tissues; the results of qPCR (quantitative real-time PCR), Western blot and IHC (immunohistochemistry) showed that Rab8a expression was up-regulated in CRC cells and tissues; in vitro functional assays verified that ectopic overexpression of Rab8a promoted the proliferation and migration of CRC cells, while the inhibition of Rab8a repressed the proliferation and migration of CRC cells; fluorescence microscope, Western blot and TOP/FOP-Flash reporter assays demonstrated that the overexpression of Rab8a could induce the EMT (epithelial-mesenchymal transition) of CRC cells by activating Wnt/β-catenin signaling pathway. Thus, this study revealed that Rab8a was up-regulated in CRC and promoted the proliferation and migration by activating Wnt/β-catenin signaling pathway and, furthermore, inducing the EMT of CRC cells.

CSTR: 32200.14.cjcb.2022.06.0003