CD8A and neoplasm: These studies suggested that Tregs could be used to monitor the immunological status of patients with OvCa.83 Patients with OvCa expressed Treg subsets with upregulated CTLA‐4 and downregulated expression of CD28.84, 85 In vitro induced CD8 Tregs blocked CD4 T‐cells proliferation via TGFβ1 and IFN‐ɣ that not only increase the number of Tregs in peripheral blood of OvCa patients, but also recruit and stimulate Treg tumor infiltration and localization.86