-Induced an increased ubiquitination of DNMT3B-Promoted autophagy and cell death-Increased LC3-I to LC3-II conversion and the downregulation of p62 in GC-Induced the autophagic cell death via the activation of the IRE1-JNK-CHOP signaling, indicating ER stress response-Inhibited the G9a (HDAC/G9a axis) and activated autophagic cell death⇒ Kaempferol activates the IRE1-JNK-CHOP signaling from cytosol to nucleus, and G9a inhibition activates autophagic cell death in GC cells. This evidence concerns the gene HDAC9 and gastric cancer.