Curcumol induces cell cycle arrest and apoptosis by inhibiting IGF-1R/PI3K/Akt signaling pathway in human nasopharyngeal carcinoma CNE-2 cells

Phytother Res. 2018 Nov;32(11):2214-2225. doi: 10.1002/ptr.6158. Epub 2018 Aug 2.

Abstract

Curcumol has been proved to possess antitumor effects in vivo and in vitro in several cancers. Previously, we have found that curcumol induced apoptosis in CNE-2 cells, but its underlying mechanism has not yet been studied well. Recently, our team clarified that curcumol inhibited colorectal cancer cells' growth partially through insulin-like growth factor 1 receptor (IGF-1R) pathway. Given the key importance of IGF-1R pathway in tumorigenesis, we want to explore whether curcumol effects on nasopharyngeal carcinoma (NPC) cells relates to IGF-1R and its downstream pathway inactivation. In this study, we found that curcumol inhibited IGF-1R and p-Akt expression in a dose- and time-dependent way. In addition, it also regulated their downstream GSK-3β's activity in CNE-2 cells, which further triggering alterations in the expression of cycle- and apoptosis-related molecules, and then leading to G0/G1-phase arrest and apoptosis. Moreover, curcumol's effect on CNE-2 cells was partly eliminated by IGF-1R's agonist IGF-1. In conclusion, our findings indicated that the inhibitory effect of curcumol on proliferation of NPC cells is related to the inhibition of IGF-1R and its downstream PI3K/Akt/GSK-3β pathway.

Keywords: IGF-1R; PI3K/Akt/GSK-3β; apoptosis; cell cycle arrest; curcumol; nasopharyngeal carcinoma.

MeSH terms

  • Apoptosis / drug effects*
  • Carcinoma / drug therapy
  • Carcinoma / pathology*
  • Cell Cycle Checkpoints / drug effects*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Glycogen Synthase Kinase 3 beta / metabolism
  • Humans
  • Insulin-Like Growth Factor I / metabolism
  • Nasopharyngeal Carcinoma
  • Nasopharyngeal Neoplasms / drug therapy
  • Nasopharyngeal Neoplasms / pathology*
  • Phosphatidylinositol 3-Kinases / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptor, IGF Type 1
  • Receptors, Somatomedin / metabolism
  • Sesquiterpenes / pharmacology*
  • Signal Transduction / drug effects*

Substances

  • IGF1 protein, human
  • IGF1R protein, human
  • Receptors, Somatomedin
  • Sesquiterpenes
  • Insulin-Like Growth Factor I
  • curcumol
  • Receptor, IGF Type 1
  • Glycogen Synthase Kinase 3 beta
  • Proto-Oncogene Proteins c-akt