The RNA editing enzyme ADAR modulated by the rs1127317 genetic variant diminishes EGFR-TKIs efficiency in advanced lung adenocarcinoma

Life Sci. 2022 May 1:296:120408. doi: 10.1016/j.lfs.2022.120408. Epub 2022 Feb 22.

Abstract

Aims: The adenosine-to-inosine (A-to-I) RNA editing controlled by the editing genes are known to diversify transcripts in human. Aberrant A-to-I editing due to dysregulation of the editing genes are involved in cancer development. However, it is still largely unclear how single nucleotide polymorphisms (SNPs) in the A-to-I editing genes confer to recurrence and/or drug resistance of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) therapy in non-small-cell lung cancer (NSCLC).

Materials and methods: In this study, we systematically evaluated and validated the role of twenty-eight potential functional genetic variants in four A-to-I editing genes (ADAR, ADARB1, ADARB2 and AIMP2) in prognosis of NSCLC patients receiving EGFR-TKIs.

Key findings: We identified the ADAR rs1127309, rs1127317, and rs2229857 SNPs markedly contributing to prognosis of patients treated with EGFR-TKIs. Interestingly, SNP rs1127317 locating in the ADAR 3'-untranslated region regulates gene expression in an allele-specific manner via modulating binding of miR-454-5p in cells. In support of this, patients with the rs1127317 C allele correlated with elevated ADAR expression in tumors showed profoundly shorten survival after EGFR-TKIs therapy compared to the A allele carriers. Silencing of ADAR notably enhanced gefitinib sensitivities of NSCLC cells.

Significance: Our findings highlight the importance of the A-to-I RNA editing in drug resistance and nominate ADAR as a potential therapeutic target for unresectable NSCLC.

MeSH terms

  • 3' Untranslated Regions
  • Adenocarcinoma of Lung / drug therapy
  • Adenocarcinoma of Lung / genetics*
  • Adenocarcinoma of Lung / mortality
  • Adenosine Deaminase / genetics*
  • Antineoplastic Agents / pharmacology*
  • Carcinoma, Non-Small-Cell Lung / drug therapy
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / mortality
  • Drug Resistance, Neoplasm / genetics
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / genetics
  • Gefitinib / pharmacology
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / mortality
  • Nuclear Proteins / genetics
  • Polymorphism, Single Nucleotide
  • Protein Kinase Inhibitors / pharmacology*
  • RNA-Binding Proteins / genetics*

Substances

  • 3' Untranslated Regions
  • AIMP2 protein, human
  • Antineoplastic Agents
  • Nuclear Proteins
  • Protein Kinase Inhibitors
  • RNA-Binding Proteins
  • EGFR protein, human
  • ErbB Receptors
  • ADAR protein, human
  • ADARB1 protein, human
  • ADARB2 protein, human
  • Adenosine Deaminase
  • Gefitinib