ATF4 and colorectal carcinoma: Huang JL et al. (2023) found that cucurbitacin B (0.005, 0.01, 0.05, 1, 5, 10, 20, 40, 100 μM for 48 h) inhibited the proliferation and induced apoptosis of CRC cells HT-29 and SW620 by concentration-dependently increasing the protein expression of p-PERK, p-eIF2α, ATF4, IRE1α and XBP1. After CHOP knockdown, the apoptosis rate was significantly decreased. Sui HH et al. (2020) reported that cucurbitacin E (0.001, 0.01, 0.1, 1, 10 μmol/L for 24, 48, 72 h) upregulated the expression of CHOP and GRP78 in HT-29 cells and induced apoptosis of CRC cells.