CCL2 and neoplasm: Besides, cytokines such as CCL2 and IL‐8 facilitate the recruitment and tumor infiltration of MDSCs, which facilitates senescence of immune cells by both the manner of direct cell‐cell interactions (via PD‐L1/PD‐1 axis) or long‐range communication (through exosomes or soluble factors like TGF‐β) [133, 134, 135].