ATF6 and colonic neoplasm: To validate our hypothesis, the expression levels for ER‐stress‐regulating genes (GRP78, XBP1, ATF6, PDI, PERK), pro‐inflammatory genes (CXCL12, MCP1, COX2, CCR5), and the cell‐cycle regulatory genes (CDK6, CCND1), as well as the inflammatory proteins (IL‐6, IFN‐γ, and CXCL10) expression and level of catalase and ROS, were studied in colon cancer cell lines before and after treatment of different concentrations of 4‐PBA.