CD4 and neoplasm: A clinical study of adoptive T cell therapy showed that a patient with widely metastatic cholangiocarcinoma who progressed through multiple chemotherapy regimens showed significant tumor regression after infusion of tumor-infiltrating CD4+ T cells of ex vivo expanded, and these T cells recognized an immunogenic neoantigen derived from the mutated ERBB2IP (ERBB2IP E805G), which encoding the ERBB2 interacting protein and highly expressed in both the original and recurrent lung lesions.