OSU-A9 induced-reactive oxygen species cause cytotoxicity in duodenal and gastric cancer cells by decreasing phosphorylated nuclear pyruvate kinase M2 protein levels

Biochem Pharmacol. 2020 Apr:174:113811. doi: 10.1016/j.bcp.2020.113811. Epub 2020 Jan 16.

Abstract

Pyruvate kinase M2 (PKM2) is a key enzyme responsible for the final step of glycolysis. It is still unclear whether PKM2 is involved in reactive oxygen species (ROS)-mediated cytotoxicity in gastrointestinal cancer, and what mechanisms are involved. One duodenal (AZ521) and two gastric (NUGC and SCM-1) cancer cell lines were treated with an indole-3-carbinol derivative OSU-A9, which caused cytotoxicity in acute myeloid leukemia through ROS generation. OSU-A9 caused a dose- and time-dependent cytotoxicity and induced apoptosis in duodenal and gastric cancer cells through ROS generation. Pretreatment with ROS scavengers rescued cancer cells from apoptosis and concomitant poly (ADP-ribose) polymerase cleavage, implying a key role of ROS in OSU-A9-induced cell death. Moreover, OSU-A9-induced ROS generation decreased protein levels of pTyr105-PKM2, and this effect was rescued by pretreatment with ROS scavengers. Interestingly, pTyr105-PKM2 protein levels decreased in the cell nucleus rather than in the cytoplasm. PKM2 overexpression partially rescued the survival of duodenal and gastric cancer cells treated with OSU-A9. Furthermore, the anticancer activity of OSU-A9 extended in vivo, as OSU-A9 administered by oral gavage suppressed the growth of AZ521 xenograft tumors in nude mice without obvious toxicity. In conclusion, OSU-A9 inhibited duodenal and gastric cancer cell proliferation through ROS generation and caused a subsequent decrease in nuclear pTyr105-PKM2 protein. These findings provide evidence for the non-canonical activity of PKM2 in cancer cell survival. Furthermore, they highlight the potential role of PKM2 as a future therapeutic target for duodenal and gastric cancer.

Keywords: Dimethyl sulfoxide (PubChem CID: 679); Duodenal cancer; Gastric cancer; Glutathione; Glutathione (PubChem CID: 124886); Indole-3-carbinol; Methylcellulose (PubChem CID: 44263857); N-acetylcysteine (PubChem CID: 12035); OSU-A9; Pyruvate kinase M2; Reactive oxygen species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Cell Survival / physiology
  • Dose-Response Relationship, Drug
  • Duodenal Neoplasms / drug therapy
  • Duodenal Neoplasms / enzymology*
  • Humans
  • Indoles / pharmacology*
  • Indoles / therapeutic use
  • Male
  • Methanol / analogs & derivatives
  • Mice
  • Mice, Nude
  • Nitrobenzenes / pharmacology*
  • Nitrobenzenes / therapeutic use
  • Phosphorylation / drug effects
  • Phosphorylation / physiology
  • Pyruvate Kinase / antagonists & inhibitors*
  • Pyruvate Kinase / metabolism*
  • Reactive Oxygen Species / metabolism*
  • Stomach Neoplasms / drug therapy
  • Stomach Neoplasms / enzymology*
  • Xenograft Model Antitumor Assays / methods

Substances

  • (1-(4-chloro-3-nitrobenzenesulfonyl)-1H-indol-3-yl)-methanol
  • Indoles
  • Nitrobenzenes
  • Reactive Oxygen Species
  • Pyruvate Kinase
  • Methanol