Moreover, signaling pathways such as mitogen activated protein kinases (MAPK) and PI3K/Akt that are frequently activated in breast cancer cells [37] modulate expression of IRF1 and STAT1 [38]–[40], further impacting the levels of IFN-γ inducible CIITA and subsequent HLA-II expression on tumor cells. The gene discussed is STAT1; the disease is breast cancer.