Interestingly, CBX7 was initially identified as an oncogene in prostate cancer, lymphoma, and gastric cancer due to its inhibitory effect on INK4a/ARF locus (Bernard et al., 2005; Scott et al., 2007; Zhang et al., 2010), while several other studies reported the tumor suppressor roles of CBX7 in ovarian, thyroid, lung, pancreatic, and colon tumors (Pallante et al., 2008; Forzati et al., 2012b; Shinjo et al., 2014; Zheng et al., 2015). This evidence concerns the gene CDKN2A and gastric cancer.