PTGS2 and colorectal cancer: ATF3 is upregulated by treatment with cyclooxygenase (Cox) inhibitor (sulindac sulfide) or Cox-1 specific inhibitor SC-560 or Cox-2 specific inhibitor SC-58125, suggesting that ATF3 may play a critical role in sulindac sulfide/SC-560/SC-58125-induced apoptosis and anti-tumorigenic effect in human colorectal cancer cells HCT-116 and SW-480 (86, 95).