The effect of 48 h of incubation with irinotecan (5 μM and 20 μM), melatonin (2000 µM), wogonin (25 μM), celastrol (0.625 μM and 1.25 μM), and their combinations on the spheroid growth of LOVO/DX cells. Abbreviations: Iry (irinotecan), Mel (melatonin), Cel (celastrol), Wog (wogonin).