Interestingly, in addition to the interaction shared with other malignant cells, Undiff-G exhibited a relatively lower expression level of IGSF4 (CADM1) which enabled cytotoxic T cells to recognize tumor cells [51], suggesting the existence of an immunosuppressive phenotype in this cluster that was associated with poor prognosis in our cohort. This evidence concerns the gene CADM1 and neoplasm.