IL10 and cancer: By secreting cytokines such as CSF1, tumors are able to recruit macrophages and support tumorigenesis by enhancing angiogenesis, tumor cell invasion, intravasation, and metastases via the secretion of metalloproteinases and inhibiting antitumor immunity by secreting immunosuppressive cytokines, such as IL10 (35–38), thus accelerating cancer development.