STAT1 and breast cancer: In comparing TEXhi and TEXlo ER+ BC tumors by differential gene expression, several of the most upregulated genes in TEXhi tumors were involved in IFN-γ signaling and response, including CXCL10, CXCL9, IFI27, IFI44, IFI44L, IFI6, IFIT1, IFIT2, IFIT3, ISG15, MX1, OAS1, OASL, and STAT1 (Supplemental Figure 8B).