CD177 and neoplasm: In human esophageal squamous cell carcinoma, LEC-mediated accumulation of CD177+ regulatory T cells (Tregs) with high expression of immune inhibitory cytokine, interleukin-35 (IL-35), is related to exhaustion of tumor-infiltrating CD8+ T cells, in creating an immunosuppressive microenvironment to favor tumor progression and resistance to immunotherapy [63].