Elevated Exosome-derived Mirnas Predict Osimertinib Resistance in Non-small Cell Lung Cancer

Abstract

Background: Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations will inevitably develop drug resistance after being treated with the third-generation EGFR-tyrosine kinase inhibitor (TKI), osimertinib. In recent years, many studies have been focusing on the ability of exosomal miRNAs secreted by tumor cells to transmit resistance information. However, the mechanism of exosome-derived miRNAs in osimertinib resistance remains unexplored.Methods: We extracted and sequenced exosomes from the supernatant of the osimertinib-resistant cell line, H1975-OR, and the sensitive cell line, H1975. The results were compared with plasma exosome sequencing before and after the appearance of drug resistance in three NSCLC clinical patients treated with oral osimertinib. Exosome-derived miRNAs that had significantly increased expression levels after osimertinib resistance were screened for expanded validation in other 64 NSCLC patients.Results: Cluster analysis of the target genes revealed that exosomal miRNAs participate in osimertinib resistance mechanisms through the activation of bypass pathways (RAS-MAPK pathway abnormality and PI3K pathway activation). Exosome-derived miR-184 (p = 0.0325) and miR-3913-5p (p = 0.0169) expression levels increased significantly after the onset of osimertinib resistance. Exosomal miR-184 was correlated with lactate dehydrogenase levels (p = 0.018). Exosomal miR-3913-5p was associated with TNM stage (p = 0.045), platelet count (p = 0.024), tumor marker carcinoembryonic antigen (p = 0.045), and distant metastases (p = 0.049), especially bone metastasis (p = 0.03). In the subgroup of patients with EGFR exon 21 L858R point mutation, miR-184 (p = 0.0104) and miR-3913-5p (p = 0.0085) derived from serum exosomes had both significantly increased expression levels. In the subgroup of T790M-positive patients, miR-3913-5p derived from serum exosomes may also be a good indicator of osimertinib resistance (p = 0.013).Conclusions: The expression levels of miR-184 and miR-3913-5p derived from exosomes in the peripheral blood of NSCLC patients could be used as biomarkers to indicate osimertinib resistance.

Elevated expression of miR-494-3p is associated with resistance to osimertinib in EGFR T790M-positive non-small cell lung cancer

“…It is possible that additional miRNAs contribute to osimertinib resistance as well. In a similar experimental setup, Li et al (32) reported miR-184 and miR-3913-5p to be upregulated in exosomes from osimertinib-resistant cells and in plasma. miR-184 did not reach the cutoff of 2-fold elevation in expression in any of our osimertinib-resistant lines and miR-3913-5p was not included in our NanoString analysis.…”