IL6 and neoplasm: IL-6 has been proposed as a possible negative prognostic factor in cancer as it has several effects on immune cell populations which impact tumor development; it regulates myeloid-derived suppressor cells (MDSCs) accumulation and activation, resulting in suppression of anti-tumor T cell and natural killer cell function, and stimulation of tumor cell proliferation, survival, invasiveness, and metastasis [10, 11].