Unique circulating microRNAs in relation to EGFR mutation status in Japanese smoker male with lung adenocarcinoma

Expression of inflammatory interleukins and selected miRNAs in non-small cell lung cancer

Tumours are characterised by an ability to avoid immune destruction and the presence of cancer-associated inflammation. Better understanding of the link between lung cancer and such inflammation is vital for early detection and personalized treatment. Thus, we examined the mRNA expression of interleukins IL-1β, IL-6, IL-17 and miR-9, miR-122 as potential useful biomarkers of NSCLC. Tumour tissues, non-cancerous tissue and blood samples were collected from 39 patients with primary NSCLC undergoing surgical treatment. The selected RNA was isolated from tissue samples and selected miRNAs from peripheral blood exosomes. This RNA was transcribed to cDNA and quantified using RT-qPCR. Significantly higher expression of the selected interleukins was observed in non-cancerous than tumour tissue, and IL-6 was significantly higher in the tumour tissue of patients with a history of ≤ 40 pack-years (PYs) (2.197, IQR: 0.821-4.415) than in those with > 40 PYs (0.461, IQR: 0.372-0.741; p = 0.037). It is clear that inflammatory processes play a role in NSCLC, as indicated by the upregulation of IL-1β and IL-6 in tumour and adjacent tissue, and that smoking has a strong influence on inflammation in tumourigenesis, demonstrated by the upregulation of IL-6 in tumour samples among patients with ≤ 40 PYs compared to > 40 PYs.

A panel of miRNAs derived from plasma extracellular vesicles as novel diagnostic biomarkers of lung adenocarcinoma

Lung cancer is the leading cause of cancer‐related morbidity and mortality worldwide, with lung adenocarcinoma (LUAD) being the most common histological subtype (approximately 40%). In the absence of reliable screening biomarkers for early diagnosis, most patients with LUAD are inevitably diagnosed at an advanced stage. MicroRNAs (miRNAs) encapsulated within plasma‐derived extracellular vesicles (EVs) may be suitable for use as noninvasive diagnostic biomarkers for aggressive malignancies, including LUAD. In this study, we first investigated the miRNA profiles of plasma‐derived EVs from LUAD patients and healthy donors, and then systematically evaluated the expression patterns of selected plasma‐derived EV miRNAs in a large cohort of patients with LUAD and healthy controls. Notably, we observed that miR‐451a, miR‐194‐5p, and miR‐486‐5p were significantly increased in EVs from LUAD patients, compared to healthy controls. The area under the curve values for the three miRNAs were 0.9040 (95% confidence interval [CI], 0.8633–0.9447) for miR‐451a, 0.7492 (95% CI, 0.6992–0.7992) for miR‐194‐5p, and 0.9574 (95% CI, 0.9378–0.9769) for miR‐486‐5p, while the AUC of the combination of these three miRNAs was 0.9650. Thus, these results suggest that these EV miRNAs may be promising candidates for the development of highly effective, noninvasive biomarkers for early LUAD diagnosis.

Lung cancer is the leading cause of cancer‐related morbidity and mortality worldwide, with lung adenocarcinoma (LUAD) being the most common histological subtype (approximately 40%). In this study, we observed that miR‐451a, miR‐194‐5p, and miR‐486‐5p in extracellular vesicles derived from plasma may be suitable as highly effective and noninvasive biomarkers for early LUAD diagnosis.

Insight into the effects of microRNA-23a-3p on pancreatic cancer and its underlying molecular mechanism

Previous studies have demonstrated that microRNA (miR)-23a-3p plays a role as an oncogene that is involved in several different types of carcinoma. However, few studies investigated the association between miR-23a-3p and pancreatic cancer (PC). The aim of the present study was to elucidate the biological functions of miR-23a-3p in PC and to investigate its underlying molecular mechanisms. The expression of miR-23a-3p in PC and adjacent normal tissues was investigated using microarrays. In order to validate the outcomes of the microarray results, reverse transcription-quantitative (RT-q)PCR was used to determine the expression levels of miR-23a-3p in PC tissues and cell lines. Furthermore, functional analyses were conducted following miR-23a-3p inhibition and overexpression, in order to assess the proliferation, invasion and migration of PC cells. Bioinformatics analysis indicated transforming growth factor-β receptor type II (TGFBR2) as a potential direct target of miR-23a-3p. Western blotting was performed in order to determine the protein expression of TGFBR2 in PC cell lines. The findings from the microarray demonstrated upregulation of miR-23a-3p in PC compared with normal tissues. RT-qPCR revealed significantly higher levels of miR-23a-3p expression in PC compared with normal control tissues or cells. Furthermore, miR-23a-3p was demonstrated to promote the proliferation, invasion and migration of PC cells, which was suppressed by the inhibition of miR-23a-3p. In addition, the miR-23a-3p expression level was negatively associated with TGFBR2 expression. Overall, the present study demonstrated the tumor-promoting effects of miR-23a-3p in PC cells. Furthermore, miR-23a-3p is a potential oncogenic regulator of PC, by targeting TGFBR2, and a biomarker or target for molecular therapy.

Identification of potential diagnostic biomarkers for pneumonia caused by adenovirus infection in children by screening serum exosomal microRNAs

Human adenovirus (HAdV) infection causes serious pneumonia in children, leading to significant morbidity and mortality rates. However, diagnostic biomarkers for HAdV‑associated pneumonia are unavailable. Serum microRNAs (miRNAs/miRs) have been recently reported as diagnostic biomarkers for several diseases. The present study performed microRNA sequencing to identify potential biomarkers among serum exosomal miRNAs, with the aim of identifying candidate biomarkers for the diagnosis of pneumonia in adenovirus‑infected children. To validate the biomarker candidates, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to determine the relative expression levels of miRNAs. As there is no endogenous reference RNA for serum miRNAs, pairwise analysis of RT‑qPCR was used in the present study to narrow down the number of biomarker candidates among all the serum exosomal miRNAs to a set of four miRNAs. As a result, the identified miRNAs (namely, miR‑450a‑5p‑miR‑103a‑3p and miR‑103b‑5p‑miR‑98‑5p) from 59 samples were considered as potential diagnostic biomarkers in adenovirus‑infected children. The results indicated that this four miRNA set could distinguish adenovirus‑infected patients from healthy controls. In conclusion, the four exosomal miRNAs identified in the present study could be considered as candidate diagnostic biomarkers for pneumonia in adenovirus‑infected children.

Unique MicroRNA and mRNA Interactions in EGFR-Mutated Lung Adenocarcinoma

The EGFR gene was one of the first molecules to be selected for targeted gene therapy. EGFR-mutated lung adenocarcinoma, which is responsive to EGFR inhibitors, is characterized by a distinct oncogenic pathway in which unique microRNA (miRNA)⁻mRNA interactions have been observed. However, little information is available about the miRNA⁻mRNA regulatory network involved. Both miRNA and mRNA expression profiles were investigated using microarrays in 155 surgically resected specimens of lung adenocarcinoma with a known EGFR mutation status (52 mutated and 103 wild-type cases). An integrative analysis of the data was performed to identify the unique miRNA⁻mRNA regulatory network in EGFR-mutated lung adenocarcinoma. Expression profiling of miRNAs and mRNAs yielded characteristic miRNA/mRNA signatures (19 miRNAs/431 mRNAs) in EGFR-mutated lung adenocarcinoma. Five of the 19 miRNAs were previously listed as EGFR-mutation-specific miRNAs (i.e., miR-532-3p, miR-500a-3p, miR-224-5p, miR-502-3p, and miR-532-5p). An integrative analysis of miRNA and mRNA expression revealed a refined list of putative miRNA⁻mRNA interactions, of which 63 were potentially involved in EGFR-mutated tumors. Network structural analysis provided a comprehensive view of the complex miRNA⁻mRNA interactions in EGFR-mutated lung adenocarcinoma, including DUSP4 and MUC4 axes. Overall, this observational study provides insight into the unique miRNA⁻mRNA regulatory network present in EGFR-mutated tumors. Our findings, if validated, would inform future research examining the interplay of miRNAs and mRNAs in EGFR-mutated lung adenocarcinoma.