DDIT3 and colorectal carcinoma: We observed an increase in PERK (not statistically significant, p = 0.066 and 0.133 at 2.0 and 2.5 mM melatonin, respectively) and CHOP (statistically significant, p = 0.040 and 0.043 at 2.0 and 2.5 mM melatonin, respectively); therefore, the PERK/CHOP pathway could potentially contribute to melatonin-mediated CRC cell death via autophagy.