The expression of circulating miR-504 in plasma is associated with EGFR mutation status in non-small-cell lung carcinoma patients

Abstract

MicroRNAs (miRNAs), key regulators of gene expression at the post-transcriptional level, are grossly misregulated in some human cancers, including non-small-cell lung carcinoma (NSCLC). The aberrant expression of specific miRNAs results in the abnormal regulation of key components of signalling pathways in tumour cells. MiRNA levels and the activity of the gene targets, including oncogenes and tumour suppressors, produce feedback that changes miRNA expression levels and indicates the cell’s genetic activity. In this study, we measured the expression of five circulating miRNAs (miR-195, miR-504, miR-122, miR-10b and miR-21) and evaluated their association with EPIDERMAL GROWTH FACTOR RECEPTOR ( EGFR ) mutation status in 66 NSCLC patients. Moreover, we examined the discriminative power of circulating miRNAs for EGFR mutant‐positive and -negative NSCLC patients using two different data normalisation approaches. We extracted total RNA from the plasma of 66 non-squamous NSCLC patients (31 of whom had tumours with EGFR mutations) and measured circulating miRNA levels using quantitative reverse transcription polymerase chain reaction (RT-qPCR). The miRNA expression levels were normalised using two endogenous controls: miR-191 and miR-16. We found significant associations between the expression of circulating miR-504 and EGFR -activating mutations in NSCLC patients regardless of the normalisation approach used ( p = 0.0072 and 0.0236 for miR-16 and miR-191 normalisation, respectively). The greatest discriminative power of circulating miR-504 was observed in patients with EGFR exon 19 deletions versus wild-type EGFR normalised to miR-191 (area under the curve (AUC) = 0.81, p < 0.0001). Interestingly, circulating miR-504 levels were significantly reduced in the v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog ( KRAS )-mutated subgroup compared to EGFR -mutated patients ( p < 0.0030) and those with EGFR/KRAS wild-type tumours ( p < 0.0359). Our study demonstrated the feasibility and potential diagnostic value of plasma miR-504 expression analysis to distinguish between EGFR -mutated and wild-type NSCLC patients. However, quality control and normalisation strategies are very important and have a major impact on the outcomes of circulating miRNA analyses.

Proteins from the DNA Damage Response: Regulation, Dysfunction, and Anticancer Strategies

“…Nearly all primary DDR-induced effectors are regulated by miRNA and interact through their RNA-binding motifs in response to DSBs [126]. MiRNAs regulate, for example, H2AX (miRNA 24 and 138 [135,136]), PARP1 (miRNA-7-5p [137]), ATM (miRNA 18a and 421 [138]), ATM and DNA-PK (miRNA 101 [139]), BRCA1 (miRNA 182 [140]), RAD51 (miRNA 193b, 103 and 107 [141]), BRCA2 (miRNA 1245 [142]), RAD52 (miRNA 302a [143]), and P53 (miRNA 125b and 504 [144,145]). Actual models propose that ncRNAs facilitate DNA repair, either by the hybridization of sncRNA to broken DNA via DDX1 and DHX9 (dead-box helicases) to form specific sequences propagating repair pathways or by the hybridization of lncRNA via RAD52-strand invasion, generating a template for high-fidelity repair [146,147].…”

Clinicopathologic Features and Molecular Biomarkers as Predictors of Epidermal Growth Factor Receptor Gene Mutation in Non-Small Cell Lung Cancer Patients

“…In patients with progressive disease, the expression level of MiRNA-10b increased compared to patients with complete remission or disease stability ( p = 0.001), while miRNA-21 had no prognostic effect on disease progression ( p = 0.720). However, Szpechcinski et al [ 98 ] found no significant differences of miRNA-10b and miRNA-21 expression level between NSCLC patients with or without EGFR mutations. The plasma miR-504 expression level in EGFR-mutated NSCLC patients was higher than those without EGFR mutations ( p = 0.0072).…”

Cell Behavior of Non-Small Cell Lung Cancer Is at EGFR and MicroRNAs Hands

“…A large body of evidence has indicated the robust diagnostic accuracy of miRNAs in patients with mutated-EGFR versus wild-type EGFR. In accordance, the receiver operating curve unveiled the potential diagnostic value (AUC = 0.81, p < 0.0001) of circulating miR-504 in characterizing patients of EGFR exon 19 deletions from wild-type EGFR normalized to miR-191 [161]. Also, using a miRNA array profiling analysis, T790M/L858R-mutated lung cancer was found to have 20 up-regulated miRNAs, including miR-1 and miR-196a, compared to EGFR wild-type lung cancer [162].…”