In response to IL-23, IL-6, and TGF-β in the tumor microenvironment, γδT cells secrete IL-17 and induce angiogenesis in a transplantable sarcoma model in mice (115) and in response to tumor-derived IL-1β, they produce IL-17 and induce systemic, G-CSF-mediated activation of neutrophils in mammary tumors to promote cancer-cell metastasis to the lungs (116). Here, IL17A is linked to breast cancer.