ID4 and cancer: Also, genes involved in various cancer-associated intracellular signaling cascades, including interferon signaling (EIF2AK2, ICAM1, STAT2, IRF3), NF-kappa B signaling (NFKB1, IKBKG, IKBKB), PI3K-Akt (PIK3R1, PTEN, PRLR) and TGF-beta signaling (TGFB1, ID4) were also differentially expressed in malignant PTs.