Salinomycin reduces epithelial-mesenchymal transition-mediated multidrug resistance by modifying long noncoding RNA HOTTIP expression in gastric cancer cells

Anticancer Drugs. 2019 Oct;30(9):892-899. doi: 10.1097/CAD.0000000000000786.

Abstract

Chemotherapy is the main treatment for advanced gastric cancer. However, the emergence of multidrug resistance (MDR) has become a major obstacle in chemotherapy in many tumors, including gastric cancer. Epithelial-mesenchymal transition (EMT), which is considered an important process in cancer development, also contributes toward tumor MDR. Salinomycin, an EMT blocker, shows broad-spectrum antitumor and chemosensitization properties. Here, we hypothesized that salinomycin could reverse the MDR of SGC7901/cisplatin (CDDP) gastric cancer cell by inhibiting EMT and further explored its possible underlying mechanisms. Our results indicated higher 50% inhibiting concentration (IC50) and stronger migration capacity in SGC7901/CDDP than in SGC7901 cells, whereas salinomycin could reduce the IC50 (50% inhibition of the concentration of chemodrugs after 4 μmol/l salinomycin treatment) and migration capacity in SGC7901/CDDP cells. At the molecular level, we found that the expression of E-cadherin, ZO-1 decreased, whereas the expression of N-cadherin, Vimentin, ZEB-1, and Twist increased in SGC7901/CDDP cells, and that salinomycin potently blocked the EMT by enhancing the expression of E-cadherin, ZO-1 and reducing the expression of N-cadherin, Vimentin, ZEB-1, and Twist in the above MDR cells. In addition, we also found that long noncoding RNA HOTTIP, an oncogenic regulator, was upregulated in SGC7901/CDDP cells, whereas its downregulation could markedly attenuate the EMT, thereby reversing the MDR. Furthermore, our data showed that the salinomycin-elicited MDR-reversion effect was associated closely with suppression of EMT through inhibition of the expression of long noncoding RNA HOTTIP. Collectively, our findings suggest a new underlying mechanism and applicable therapeutic regimen for MDR gastric cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Cell Line, Tumor
  • Cisplatin / pharmacology
  • Down-Regulation / drug effects
  • Down-Regulation / genetics
  • Drug Resistance, Multiple / drug effects*
  • Drug Resistance, Multiple / genetics
  • Drug Resistance, Neoplasm / drug effects*
  • Drug Resistance, Neoplasm / genetics
  • Epithelial-Mesenchymal Transition / drug effects*
  • Epithelial-Mesenchymal Transition / genetics
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • Pyrans / pharmacology*
  • RNA, Long Noncoding / genetics*
  • Signal Transduction / drug effects
  • Signal Transduction / genetics
  • Stomach Neoplasms / drug therapy*
  • Stomach Neoplasms / genetics
  • Up-Regulation / drug effects
  • Up-Regulation / genetics

Substances

  • Antineoplastic Agents
  • Pyrans
  • RNA, Long Noncoding
  • long noncoding RNA HOTTIP, human
  • salinomycin
  • Cisplatin