Tumor‑released lncRNA H19 promotes gefitinib resistance via packaging into exosomes in non‑small cell lung cancer

Oncol Rep. 2018 Dec;40(6):3438-3446. doi: 10.3892/or.2018.6762. Epub 2018 Oct 3.

Abstract

Currently, resistance to tyrosine kinase inhibitors, such as gefitinib, has become one major obstacle for improving the clinical outcome of patients with metastatic and advanced‑stage non‑small cell lung cancer (NSCLC). While cell behavior can be modulated by long non‑coding RNAs (lncRNAs), the contributions of lncRNAs within extracellular vesicles (exosomes) are largely unknown. To this end, the involvement and regulatory functions of lncRNA H19 wrapped by exosomes during formation of gefitinib resistance in human NSCLC were investigated. Gefitinib‑resistant cell lines were built by continuously grafting HCC827 and HCC4006 cells into gefitinib‑contained culture medium. RT‑qPCR assays indicated that H19 was increased in gefitinib‑resistant cells when compared to sensitive parent cells. Functional experiments revealed that silencing of H19 potently promoted gefitinib‑induced cell cytotoxicity. H19 was secreted by packaging into exosomes and this packaging process was specifically mediated by hnRNPA2B1. H19 wrapped in exosomes could be transferred to non‑resistant cells, thus inducing gefitinib resistance. Moreover, treatment‑sensitive cells with exosomes highly‑expressing H19 induced gefitinib resistance, while knockdown of H19 abrogated this effect. In conclusion, H19 promoted gefitinib resistance of NSCLC cells by packaging into exosomes. Therefore, exosomal H19 may be a promising therapeutic target for EGFR+ NSCLC patients.

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / therapeutic use
  • Carcinoma, Non-Small-Cell Lung / drug therapy*
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Cell Line, Tumor
  • Cell Proliferation
  • Drug Resistance, Neoplasm / genetics*
  • Exosomes / genetics
  • Exosomes / metabolism*
  • Exosomes / ultrastructure
  • Gefitinib / pharmacology*
  • Gefitinib / therapeutic use
  • Gene Expression Regulation, Neoplastic
  • Gene Knockdown Techniques
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B / metabolism
  • Humans
  • Lung Neoplasms / drug therapy*
  • Lung Neoplasms / genetics
  • Microscopy, Electron, Transmission
  • RNA, Long Noncoding / genetics
  • RNA, Long Noncoding / metabolism*

Substances

  • Antineoplastic Agents
  • H19 long non-coding RNA
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B
  • RNA, Long Noncoding
  • hnRNP A2
  • Gefitinib