The 2F8cis cells, which trigger carcinosarcoma tumors that are abundantly infiltrated by T cells (Grabosch et al., 2019), express the highest levels of both RANTES and IP-10, likely explaining their immune ‘hot’ phenotype and partial response to immune checkpoint blockade (Grabosch et al., 2019). The gene discussed is CXCL10; the disease is carcinosarcoma.