CMTM6 and head and neck squamous cell carcinoma: Other studies have pointed out that the deletion of CMTM6 can reduce tumor-specific T cell activity and cause tumor “immune escape,” thus showing that CMTM6 may be a tumor suppressor gene in tumorigenesis (Zhu et al., 2019), but at the same time, more studies have indicated that CMTM6 is highly expressed in head and neck squamous cell carcinoma, hepatocellular carcinoma, non–small cell lung cancer, and gliomas and showed a poor prognosis (Guan et al., 2018; Lisio et al., 2019; Chen et al., 2020; Liu et al., 2021).