IL6 and neoplasm: ESCC cells may also suppress the anti-tumor immune response and facilitate tumor progression by secreting some immunosuppressive cytokines that play a vital role in enhancing immune escape in the TME, including transforming growth factor-β (TGF-β), IL-6, and IL-10, etc. Previous studies have demonstrated that the expression levels of these immunosuppressive cytokines are significantly higher in ESCC tissues and are associated with a decrease in infiltrating lymphocytes in TME and a worse prognosis (32–35).