IL6 and lymphoma: Non-malignant cells of the tumor ecosystem including tumor-associated macrophages (TAMs), myeloid-derived suppressor cells or subpopulations of T lymphocytes also undergo hypoxia-induced phenotypic changes that critically contribute to the survival of lymphoma cells by fostering immunosuppression, by aberrant expression of programmed death ligand 1 and by secreting immunosuppressive cytokines, e.g., IL6 or IL10 [78].