Anti-cancer effects of 3, 3'-diindolylmethane on human hepatocellular carcinoma cells is enhanced by calcium ionophore: The role of cytosolic Ca2+ and P38 mapk

Yuanyue Jiang, Yanfei Fang, Yang Ye, Xinming Xu, Bingfang Wang, Jie Gu, Michael Aschner, Jian Chen, Rongzhu Lu

Research output: Contribution to journalArticle

2 Scopus citations

Abstract

Purpose: 3,3'-Diindolylmethane (DIM), derived from indole-3-carbinol (I3C) in the Brassica species of cruciferous vegetables, has anticancer effects, but its exact underlying mechanism of action is unknown. We explored the roles of cytosolic free calcium ([Ca2+]i) and p38 MAPK in the anti-cancer effects of DIM in human hepatocellular carcinoma cells. Methods: Cell proliferation was measured with a Cell Counting Kit-8 (CCK-8) and the clonogenic formation assay. Cell apoptosis was examined by?ow cytometric analysis and Hoechst dye staining. Cleaved-caspase3, cleaved-PARP, Bax, total, and phosphorylated p38 MAPK were assayed by western blotting. [Ca2+]i was measured with Fluo-3/AM by?uorescence microscopy. A23187, a calcium ionophore, was used to increase [Ca2+]i levels. Results: DIM inhibited cell proliferation in both SMMC-7721 and HepG2 cells in a concentration-and time-dependent manner. DIM also enhanced phosphorylation of p38 MAPK (p-p38), which was attenuated by SB203580. The proliferation inhibition and apoptosis induction by DIM were also blunted. In addition, DIM increased [Ca2+]i in HCC cells, and this effect was inhibited by the calcium chelator, BAPTA-AM, resulting in reduced p-p38 MAPK activation and apoptosis in DIM-treated cells, though the proliferation inhibition by DIM was unchanged. However, the DIM-induced cell proliferation inhibition and apoptosis were signifcantly enhanced by A23187, a selective calcium ionophore, which was attributed to exaggerated p-p38 MAPK. Conclusions: The calcium ionophore enhanced DIM-induced anti-cancer effects in hepatocellular carcinoma cells, secondary to [Ca2+]i-dependent activation of p38 MAPK. Treatment with a combination of DIM and calcium ionophore may offer a new approach to enhance the chemotherapeutic effcacy in liver cancer.

Original languageEnglish (US)
Article number1167
JournalFrontiers in Pharmacology
Volume10
DOIs
StatePublished - 2019

Keywords

  • 3,3'-diindolylmethane
  • Apoptosis
  • Cytosolic Ca
  • Hepatocellular carcinoma cells
  • P38 MAPK
  • Proliferation

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)

Fingerprint Dive into the research topics of 'Anti-cancer effects of 3, 3'-diindolylmethane on human hepatocellular carcinoma cells is enhanced by calcium ionophore: The role of cytosolic Ca<sup>2+</sup> and P38 mapk'. Together they form a unique fingerprint.

  • Cite this