Clinical Significance of miR-210 and its Prospective Signaling Pathways in Non-Small Cell Lung Cancer: Evidence from Gene Expression Omnibus and the Cancer Genome Atlas Data Mining with 2763 Samples and Validation via Real-Time Quantitative PCR.

BACKGROUND/AIMS: Since the function of microRNA (miR)-210 in non-small cell lung cancer (NSCLC) remains unclear, we aimed to explore the clinical significance of miR-210 in NSCLC. METHODS: NSCLC-related data from 1673 samples on Gene Expression Omnibus and 1090 samples on The Cancer Genome Atlas were obtained and analyzed. The expression level of miR-210 was validated via real-time quantitative PCR analysis with 125 paired clinical samples. A meta-analysis was performed to generate a comprehensive understanding of miR-210 expression and its clinical significance in NSCLC. In addition, bioinformatics analysis was also conducted to reveal the potential underlying mechanism of miR-210 action in NSCLC. RESULTS: miR-210 expression was consistently elevated in NSCLC solid tissue samples. However, its expression was controversial in easily obtained body fluids (i.e., blood, plasma, and serum). Moreover, an overall pooled meta-analysis implied a comparatively higher level of miR-210 expression in NSCLC cancerous tissue than in normal control tissue (P < 0.001). In addition, a meta-analysis of outcome revealed a significant diagnostic capacity of miR-210 in NSCLC by detecting its expression in serum and sputum (area under the summary receiver operating characteristic curve 0.82 and 0.81, respectively). miR-210 overexpression was associated with poor progression-free survival (PFS) in NSCLC and was negatively related to overall survival and disease-free survival. Bioinformatic gene enrichment and annotation analyses showed that the target genes of miR-210 were greatly enriched in cell adhesion and plasma membrane, and three pathways were considered to be the main functional circuits of miR-210: renin secretion, the cGMP-PKG signaling pathway, and cell adhesion molecules. CONCLUSION: In NSCLC, miR-210 expression was elevated and overexpression indicated poor PFS. Expression level of miR-210 in serum and sputum showed significant diagnostic value for NSCLC.

Clinical value of miR-198-5p in lung squamous cell carcinoma assessed using microarray and RT-qPCR.

BACKGROUND: To examine the clinical value of miR-198-5p in lung squamous cell carcinoma (LUSC). METHODS: Gene Expression Omnibus (GEO) microarray datasets were used to explore the miR-198-5p expression and its diagnostic value in LUSC. Real-time reverse transcription quantitative polymerase chain reaction was used to evaluate the expression of miR-198-5p in 23 formalin-fixed, paraffin-embedded (FFPE) LUSC tissues and corresponding non-cancerous tissues. The correlation between miR-198-5p expression and clinic pathological features was assessed. Meanwhile, putative target messenger RNAs of miR-198-5p were identified based on the analysis of differentially expressed genes in the Cancer Genome Atlas (TCGA) and 12 miRNA prediction tools. Subsequently, the putative target genes were sent to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses. RESULTS: MiR-198-5p was low expressed in LUSC tissues. The combined standard mean difference (SMD) values of miR-198-5p expression based on GEO datasets were - 0.30 (95% confidence interval (CI) - 0.54, - 0.06) and - 0.39 (95% CI - 0.83, 0.05) using fixed effect model and random effect model, respectively. The sensitivity and specificity were not sufficiently high, as the area under the curve (AUC) was 0.7749 (Q* = 0.7143) based on summarized receiver operating characteristic (SROC) curves constructed using GEO datasets. Based on the in-house RT-qPCR, miR-198-5p expression was 4.3826 ± 1.7660 in LUSC tissues and 4.4522 ± 1.8263 in adjacent normal tissues (P = 0.885). The expression of miR-198-5p was significantly higher in patients with early TNM stages (I-II) than that in cases with advanced TNM stages (III-IV) (5.4400 ± 1.5277 vs 3.5690 ± 1.5228, P = 0.008). Continuous variable-based meta-analysis of GEO and PCR data displayed the SMD values of - 0.26 (95% CI - 0.48, - 0.04) and - 0.34 (95% CI - 0.71, 0.04) based on fixed and random effect models, respectively. As for the diagnostic value of miR-198-5p, the AUC based on the SROC curve using GEO and PCR data was 0.7351 (Q* = 0.6812). In total, 542 genes were identified as the targets of miR-198-5p. The most enriched Gene Ontology terms were epidermis development among biological processes, cell junction among cellular components, and protein dimerization activity among molecule functions. The pathway of non-small cell lung cancer was the most significant pathway identified using Kyoto Encyclopedia of Genes and Genomes analysis. CONCLUSION: The expression of miR-198-5p is related to the TNM stage. Thus, miR-198-5p might play an important role via its target genes in LUSC.

Effect of miR­146a­5p on tumor growth in NSCLC using chick chorioallantoic membrane assay and bioinformatics investigation.

Our previous study demonstrated that the expression of miR­146a­5p was downregulated in non­small cell lung cancer (NSCLC) tissue, which affected the progression and prognosis of patients with NSCLC. Thus, the present study was conducted to investigate the functional mechanism of miR­146a­5p in tumorigenesis and angiogenesis in NSCLC. Following the construction of a H460 NSCLC cell line in which miR­146a­5p was overexpressed via lentivirus transduction, the NSCLC chick embryo chorioallantoic membrane (CAM) model was established by transplanting miR­146a­5p­overexpressing NSCLC cells into the CAM. Then, the size of the neoplasms within the CAM was measured, the vessel ratio was calculated, and the cellular morphology, metastasis and inflammation of tumor cell was observed using hematoxylin and eosin staining. The target genes of miR­146a­5p were predicted by 12 online software programs; these genes were then subjected to Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway annotations using the Database for Annotation, Visualization and Integrated Discovery 6.7 as well as constructed into a protein interaction network using protein­protein interaction from Search Tool for the Retrieval of Interacting Genes/Proteins. The xenograft tumor size and angiogenesis conditions of the miR­146a­5p­overexpressing group (volume 6.340±0.066 mm3, vessel ratio 9.326±0.083) was obviously restricted (P<0.001) when compared with the low expression group (volume 30.13±0.06 mm3, vessel ratio 16.94±0.11). In addition, marked necrosis along with inflammatory cell infiltration was observed with the HE­stained slices from the miR­146a­5p low expression group. Regarding the results of the target gene prediction, cancer and toll­like receptor signaling were the two most significant pathways represented among the target genes, while JUN, EGFR and RAC1 were the most relevant proteins among the selected potential targets of miR­146a­5p. In a CAM xenograft tumor model, overexpression of miR­146a­5p inhibited the tumorigenesis and angiogenesis of an NSCLC cell line. miR­146a­5p may act as a tumor suppressor gene in NSCLC and have moderate prognostic value in lung cancer.

The clinical value of lncRNA NEAT1 in digestive system malignancies: A comprehensive investigation based on 57 microarray and RNA-seq datasets.

This comprehensive investigation was performed to evaluate the expression level and potential clinical value of NEAT1 in digestive system malignancies. A total of 57 lncRNA datasets of microarray or RNA-seq and 5 publications were included. The pooled standard mean deviation (SMD) indicated that NEAT1 was down-regulated in esophageal carcinoma (ESCA, SMD = -0.35, 95% CI: -0.5~-0.20, P < 0.0001) and hepatocellular carcinoma (HCC, SMD = -0.47, 95% CI: -0.60~-0.34, P < 0.0001), while in pancreatic cancer (PC), NEAT1 was up-regulated (SMD = 0.45, 95% CI: 0.2~0.71, P = 0.001). However, NEAT1 expression in gastric cancer (GC), colorectal cancer (CRC), biliary tract cancer (BTC) and gallbladder carcinoma (GBC) showed no significant difference between cancer and control groups. The pooled area under the curve values for ESCA, GC, CRC, PC and HCC were 0.60, 0.89, 0.81, 0.77 and 0.69, respectively. Furthermore, our result demonstrated that a high expression of NEAT1 predicted an unfavorable prognosis in patients with digestive system malignancies (HR: 1.50, 95% CI: 1.28-1.76, P < 0.0001). Our study suggests that NEAT1 may play different roles in the initiation and progression of digestive system cancers and could be a potential diagnostic and prognostic biomarker in patients with digestive system carcinomas. Further and stricter studies with a larger number of cases are necessary to strengthen our conclusions.