CD4 and neoplasm: TIM-3 is preferentially expressed on CD4 + T cell subsets (Th1/Th17), CD8 + T cell subsets (Tc1) and regulatory T cells (Tregs) to generate inhibitory signals, resulting in inhibition of T cell activation and proliferation, reducing the production of cytokines that positively regulate immune responses, and playing a negative regulatory role in the process of anti-tumor immunity [102].