Bioinformatics Analysis Predicts hsa_circ_0026337/miR-197-3p as a Potential Oncogenic ceRNA Network for Non-small Cell Lung Cancers

Circ_0001715 Functions as a miR-1249-3p Sponge to Accelerate the Progression of Non-small Cell Lung Cancer via Upregulating the Level of FGF5

Circular RNAs (circRNAs) have been widely involved in the malignant development of human cancers. Circ_0001715 was aberrantly upregulated in non-small cell lung cancer (NSCLC). However, circ_0001715 function has never been researched. This study was designed to investigate the role and mechanism of circ_0001715 in NSCLC. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to examine the levels of circ_0001715, microRNA-1249-3p (miR-1249-3p) and Fibroblast Growth Factor 5 (FGF5). The proliferation detection was conducted using colony formation assay and EdU assay. Cell apoptosis was analyzed via flow cytometry. Wound healing assay and transwell assay were used for determination of migration and invasion, respectively. The protein levels were measured through western blot. Target analysis was carried out via dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Xenograft tumor model was established in mice for in vivo research. The significant upregulation of circ_0001715 was detected in NSCLC samples and cells. Circ_0001715 knockdown induced the inhibitory effects on proliferation, migration and invasion but the promoting effect on apoptosis of NSCLC cells. Circ_0001715 could interact with miR-1249-3p. The regulatory role of circ_0001715 was achieved by sponging miR-1249-3p. Furthermore, miR-1249-3p targeted FGF5 and miR-1249-3p acted as a cancer inhibitor by targeting FGF5. Moreover, circ_0001715 upregulated the FGF5 level via targeting miR-1249-3p. In vivo assay showed that circ_0001715 promoted the NSCLC progression through the miR-1249-3p/FGF5 axis. The current evidence elucidated that circ_0001715 served as an oncogenic regulator in NSCLC progression by depending on the miR-1249-3p/FGF5 axis.

CircSCN8A suppresses malignant progression and induces ferroptosis in non-small cell lung cancer by regulating miR-1290/ACSL4 axis

Circular RNAs (CircRNAs) are reported to exert vital regulatory roles in the occurrence and development of various human malignancies, including non-small cell lung cancer (NSCLC). Bioinformatics methods identified the down-regulation of circSCN8A (circBase ID: hsa_circ_0026337) in NSCLC tissues. However, its biological functions and molecular mechanisms in NSCLC remain unknown. In this study, we found that circSCN8A expression was down-regulated in NSCLC tissues and cells. Low circSCN8A expression was positively associated with aggressive clinicopathological characteristics and poor prognosis in NSCLC patients. CircSCN8A suppressed cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro and blocked tumor growth in vivo. Moreover, circSCN8A promoted cell ferroptosis in NSCLC. Mechanistically, circSCN8A acted as a competing endogenous RNA (ceRNA) by sponging miR-1290 to enhance the expression of long-chain acyl-CoA synthetase-4 (ACSL4). Furthermore, the knockdown of ACSL4 or overexpression of miR-1290 reversed the effect of circSCN8A on facilitating ferroptosis and inhibiting cell proliferation and metastasis. In summary, circSCN8A represses cell proliferation and metastasis in NSCLC by regulating the miR-1290/ACSL4 axis to induce ferroptosis. Thus, circSCN8A may represent a promising therapeutic target against NSCLC.

The Network of miRNA-mRNA Interactions in Circulating T Cells of Patients Following Major Trauma - A Pilot Study

Purpose

Following major trauma, genes involved in adaptive immunity are downregulated, which accompanies the upregulation of genes involved in systemic inflammatory responses. This study investigated microRNA (miRNA)-mRNA interactome dysregulation in circulating T cells of patients with major trauma.

Patients and Methods

This study included adult trauma patients who had an injury severity score ≥16 and required ventilator support for more than 48 h in the intensive care unit. Next-generation sequencing was used to profile the miRNAs and mRNAs expressed in CD3+ T cells isolated from patient blood samples collected during the injury and recovery stages.

Results

In the 26 studied patients, 9 miRNAs (hsa-miR-16-2-3p, hsa-miR-16-5p, hsa-miR-185-5p, hsa-miR-192-5p, hsa-miR-197-3p, hsa-miR-23a-3p, hsa-miR-26b-5p, hsa-miR-223-3p, and hsa-miR-485-5p) were significantly upregulated, while 58 mRNAs were significantly downregulated in T cells following major trauma. A network consisting of 8 miRNAs and 22 mRNAs interactions was revealed by miRWalk, with three miRNAs (hsa-miR-185-5p, hsa-miR-197-3p, and hsa-miR-485-5p) acting as hub genes that regulate the network. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested that “chemokine signaling pathway” was the predominant pathway.

Conclusion

The study revealed a miRNA-mRNA interactome consisting of 8 miRNAs and 22 mRNAs that are predominantly involved in chemokine signaling in circulating T cells of patients following major trauma.

A Novel Strategy for Identifying NSCLC MicroRNA Biomarkers and Their Mechanism Analysis Based on a Brand-New CeRNA-Hub-FFL Network

Finding reliable miRNA markers and revealing their potential mechanisms will play an important role in the diagnosis and treatment of NSCLC. Most existing computational methods for identifying miRNA biomarkers only consider the expression variation of miRNAs or rely heavily on training sets. These deficiencies lead to high false-positive rates. The independent regulatory model is an important complement to traditional models of co-regulation and is more impervious to the dataset. In addition, previous studies of miRNA mechanisms in the development of non-small cell lung cancer (NSCLC) have mostly focused on the post-transcriptional level and did not distinguish between NSCLC subtypes. For the above problems, we improved mainly in two areas: miRNA identification based on both the NOG network and biological functions of miRNA target genes; and the construction of a 4-node directed competitive regulatory network to illustrate the mechanisms. NSCLC was classified as lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) in this work. One miRNA biomarker of LUAD (miR-708-5p) and four of LUSC (miR-183-5p, miR-140-5p, miR-766-5p, and miR-766-3p) were obtained. They were validated using literature and external datasets. The ceRNA-hub-FFL involving transcription factors (TFs), microRNAs (miRNAs), mRNAs, and long non-coding RNAs (lncRNAs) was constructed. There were multiple interactions among these components within the net at the transcriptional, post-transcriptional, and protein levels. New regulations were revealed by the network. Meanwhile, the network revealed the reasons for the previous conflicting conclusions on the roles of CD44, ACTB, and ITGB1 in NSCLC, and demonstrated the necessity of typing studies on NSCLC. The novel miRNA markers screening method and the 4-node directed competitive ceRNA-hub-FFL network constructed in this work can provide new ideas for screening tumor markers and understanding tumor development mechanisms in depth.

Elevated BTG2 improves the radiosensitivity of non-small cell lung cancer (NSCLC) through apoptosis

BACKGROUND

To identify radio-responsive genes and explore the biological function of encoded proteins in non-small cell lung cancer (NSCLC).

METHODS

Radio-responsive genes in irradiated H460 cells were screened from microarray data deposited in the Gene Expression Omnibus (GEO) database. A quantitative real time polymerase chain reaction assay was used to detect the expression of candidate radio-responsive genes in irradiated cells. CCK-8 assay, EDU assay, clone formation assay, immunofluorescence and flow cytometry were conducted to evaluate the biological function of B cell translocation gene 2 (BTG2) in NSCLC.

RESULTS

Bioinformatic analysis using GES20549 showed that BTG2 was a radio-responsive gene in irradiated H460 cells. The mRNA expression level of BTG2 was lower in H460 cells compared with that in BEAS-2B normal lung epithelial cells. BTG2 expression was elevated upon IR exposure, in a dose-dependent but not a time-dependent manner. CCK-8 and EDU assays revealed that BTG2 overexpression inhibited the growth rate of irradiated cells. Clone formation showed that elevated BTG2 promoted DNA damage of irradiated H460 cells. The number of γ-H2AX foci induced by DNA damage was also markedly increased upon BTG2 overexpression. Flow cytometry showed that BTG2 increased IR-induced cell apoptosis.

CONCLUSIONS

BTG2 may be a novel radio-responsive factor and a promising therapeutic target for radiotherapy of NSCLC.