Numerous studies have shown that CMTM family members have a variety of important roles in the occurrence and progression of cancer. CMTM7 has also been reported to be down-regulated in some digestive system tumors, but the expression patterns and pathological role of CMTM7 in gastric cancer remains unclear. In this study, we found that both CMTM7 and SOX10 were significantly down-regulated in gastric cancer tissues compared with paracancerous tissues, and the expression pattern of CMTM7 and SOX10 were strongly correlated (r = 0.6455, p < 0.001). Further, through bioinformatics technology and luciferase assay, we identify that SOX10 can be a transcriptional regulator of CMTM7 to mediate the expression of CMTM7 in gastric cancer. In addition, we found silencing the expression of CMTM7 can increase the proliferation and tumorigenesis of gastric cancer cells in vivo and in vitro. More interestingly, overexpression of SOX10 in cell lines stably silencing CMTM7 expression significantly inhibited the proliferation and tumor growth of gastric cancer. Therefore, our results demonstrate that CMTM7 as a tumor suppressor is down-regulated in gastric cancer, and SOX10 can regulate the proliferation and tumor formation of gastric cancer by regulating the expression of CMTM7. (C) 2018 Published by Elsevier Inc.