Substantially reduced expression of PIAS1 is associated with colon cancer development

Protein inhibitors of activated STATs (PIAS) regulate the interferon-gamma (IFN-gamma) signaling pathway, which has numerous effects on tumor development and tumor cell biology. PIAS's also regulate STAT family members not directly involved in IFN-gamma signaling. This project was designed to assess PIAS1 expression in colon cancer.To determine whether PIAS1, one of the PIAS family members, or IFN-gamma signaling pathway components could be used to stratify colon tumors, we stained tissue microarrays for PIAS1, interferon regulatory factor-1 (IRF-1) and STAT1alpha.PIAS1 staining of the colon cancer tissue microarrays indicated a strong correlation of normal colon cells, and adenomas, with high expression of both PIAS1 and IRF-1.The PIAS1 results in particular may represent a basis for new approaches for efficiently distinguishing adenomas from colon cancer.