High relative ratios of Treg cells to CD4+ or CD8+ Tconv cells within tumors are associated with poor prognoses in patients with a variety of cancers, including ovarian cancer (15, 16), breast cancer (17), non-small cell lung carcinoma (18), hepatocellular carcinoma (19), renal cell carcinoma (20), pancreatic cancer (21), gastric cancer (22), cervical cancer (23), intrahepatic cholangiocarcinoma (24) and colorectal carcinoma (25). Here, CD8A is linked to cancer.