The EGFR pathway is involved in the regulation of PD-L1 expression via the IL-6/JAK/STAT3 signaling pathway in EGFR-mutated non-small cell lung cancer

Int J Oncol. 2016 Oct;49(4):1360-8. doi: 10.3892/ijo.2016.3632. Epub 2016 Jul 26.

Abstract

Negative regulation of the signal mediated by the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway can effectively inhibit the function of T and B cells, which play a key role in the regulation of immune response. Recently, emerging evidence has suggested that the expression of PD-L1 is related to the mutation status of the epidermal growth factor receptor (EGFR). Moreover, the activation of the EGFR signaling pathway can induce expression of PD-L1. In the present study, we demonstrated that activated EGFR can upregulate the expression of PD-L1 through the interleukin 6/Janus kinase/signal transducer and activator of transcription 3 (IL-6/JAK/STAT3) signaling pathway in non-small cell lung cancer (NSCLC) cells. Cells treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) can downregulate the activation of the IL-6/JAK/STAT3 pathway, which subsequently reduces the expression of PD-L1. Furthermore, silencing of PD-L1 expression in NSCLC cells correlated with inhibition of cell proliferation and enhanced tumor cell apoptosis. In summary, our research indicates that EGFR is involved in the regulation of PD-L1 expression and cell proliferation via the IL-6/JAK/STAT3 signaling pathway in NSCLC. The present study suggests the potential of combined targeted therapy with immunotherapy in the treatment of NSCLC.

MeSH terms

  • B7-H1 Antigen / genetics*
  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Cell Proliferation / drug effects
  • ErbB Receptors / genetics*
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Interleukin-6 / genetics
  • Janus Kinases / genetics
  • Lung Neoplasms / genetics*
  • Mutation*
  • Protein Kinase Inhibitors / pharmacology
  • STAT3 Transcription Factor / genetics
  • Signal Transduction / drug effects

Substances

  • B7-H1 Antigen
  • CD274 protein, human
  • IL6 protein, human
  • Interleukin-6
  • Protein Kinase Inhibitors
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • EGFR protein, human
  • ErbB Receptors
  • Janus Kinases