Dataset Information

Increased PD-L1 expression in erlotinib-resistant NSCLC cells with MET gene amplification is reversed upon MET-TKI treatment.

ABSTRACT:

Introduction

Cancer cells can achieve immune evasion by expressing the programmed death receptor 1 ligand (PD-L1) on the cell surface. Blockade of the receptor (PD-1) can avert this evasion. Here we aim at investigating PD-L1 expression in erlotinib-resistant lung cancer cells with MET proto-oncogene (MET) gene amplification.

Materials and methods

We employed an erlotinib-resistant NSCLC cell line with MET gene amplification. PD-L1 mRNA (qPCR) and protein (flow cytometry) expression was investigated after treatment with MET and mitogen-activated protein kinase (MAPK) targeting drugs (crizotinib and SCH772984, respectively).

Results

We demonstrate that PD-L1 expression is increased in erlotinib-resistant non-small cell lung cancer (NSCLC) cells with MET gene amplification. Targeted inhibition of MET significantly decreases both gene and protein expression of PD-L1. Further, we demonstrate that inhibiting MAPK also results in a significant decrease in PD-L1 expression. Taken together these results show that expression of PD-L1 in the erlotinib-resistant cell line is associated with MET activity, and the downstream MAPK pathway.

Conclusions

Our results demonstrate that PD-L1 expression is increased in erlotinib resistant NSCLC cells with MET gene amplification and that the increase can be averted by targeted inhibition of MET.

SUBMITTER: Demuth C

PROVIDER: S-EPMC5620250 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Publications

Increased PD-L1 expression in erlotinib-resistant NSCLC cells with <i>MET</i> gene amplification is reversed upon MET-TKI treatment.

Demuth Christina C Andersen Morten Nørgaard MN Jakobsen Kristine Raaby KR Madsen Anne Tranberg AT Sørensen Boe Sandahl BS

Oncotarget 20170804 40

<h4>Introduction</h4>Cancer cells can achieve immune evasion by expressing the programmed death receptor 1 ligand (PD-L1) on the cell surface. Blockade of the receptor (PD-1) can avert this evasion. Here we aim at investigating PD-L1 expression in erlotinib-resistant lung cancer cells with <i>MET proto-oncogene</i> (<i>MET</i>) gene amplification.<h4>Materials and methods</h4>We employed an erlotinib-resistant NSCLC cell line with <i>MET</i> gene amplification. PD-L1 mRNA (qPCR) and protein (flo ...[more]

PMID: 28978110

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