Regulatory T cells play a central inhibitory role in the tumor microenvironment and inhibit the function of effector immune cells through a variety of mechanisms, thereby promoting tumor escape from immune surveillance and leading to tumor growth and metastasis (49, 50).Tregs directly inhibit the killing activity of CD8+ T cells by secreting inhibitory cytokines such as IL-10 and TGF-β, and hinder the migration and activation of T cells (51). Here, TGFB1 is linked to neoplasm.