E2 can cause immunosuppression through inhibition of cytotoxic T-cells- and NK cell-mediated tumor cell elimination [179], while E2-treated ERα-expressing CD4+CD25- T-cells regain CD25 expression, so such transformed CD4+CD25+ T-cells then manifest an immunosuppressive Treg phenotype [180]. The gene discussed is ESR1; the disease is neoplasm.