In this study, we report that the mRNA expression levels of CMTM1, CMTM2, CMTM4, and CMTM5 are significantly downregulated whereas those of CMTM3, CMTM6, and CMTM8 are significantly upregulated in human cancers; therefore, our results indicate that the mRNA expression levels of CMTM family members can be highly divergent. Here, CMTM5 is linked to cancer.