•Secretes cytokines (IL-10, TGF-β, lymphotoxin), immunosuppressive molecules (PD-L1, granzyme B)•Inhibit T-cell activation and CD4+ T cell response•Promote metastasis and angiogenesis•Suppress CD8+ T cell and NK cell anti-tumor activity•Recruit myeloid cells antibodies to induce immunosuppressive environment. Here, CD4 is linked to neoplasm.