PTGS2 and colorectal carcinoma: Similar to DCLK1-IN-1, DDQ-1 displayed potent activity against DCLK1 kinase activity (IC50 = 3 nM), CRC cell growth (HCT116 and hCRC#1 cells, with IC50 = 0.685 μM and 0.653 μM, respectively), and the XRCC5/COX2/PGE2 signaling cascade (Figure S13B-E).