Immunosuppressive cells upregulate immunosuppressive cytokines such as IL-4, IL-10, IL-13 and transforming growth factor beta (TGF-β), stimulate angiogenesis by expressing VEGF and HIF-1α, and express ICPs, which are involved in tumor development, immunosuppressive TME formation, and anti-tumor immunity evasion (11–13, 36). Here, IL4 is linked to neoplasm.