Recent studies have suggested that CMTM6 is coexpressed with PD-L1 in a variety of cancers and has been proven to be an independent prognostic factor of gastric cancer and liver cancer (Guan et al., 2018; Li et al., 2020; Liu et al., 2020a; Zhu et al., 2019). Here, CMTM6 is linked to gastric cancer.