ATF4 and liver cancer: (−)-Agelasidine A (derived from Agelas nakamurai) induced cytotoxicity in HepG2 and Hep3B liver cancer cell lines (with IC50 values of 129 μM and 69.9 μM, respectively), associated with apoptotic features and ER stress (elevated levels of GRP78, CHOP, ATF4, and p-PERK) [90].