CD4 and neoplasm: In bladder cancer, exosomal miR-92b-3p and miR-1231-5p derived from the murine bladder cancer cell line MB49 can induce macrophage polarization into an immunosuppressive phenotype by inhibiting PTEN expression and activating the AKT/STAT3/6 pathway, suppressing the proliferation of CD4+T and CD8+T cells, and facilitating tumor growth (92).