Carnosol is a potent Ribosomal S6 Kinase (RSK2) inhibitor that could be useful for treating gastric cancer, with an IC50 of ~5.5 µM[1]. Carnosol, a Nrf2 activator, increases the nuclear levels of Nrf2 and can promote the expression of heme oxygenase 1 (HMOX1)[2][3].