Long non-coding RNA TUG1 mediates 5-fluorouracil resistance by acting as a ceRNA of miR-197-3p in colorectal cancer

Hsa_circ_001988 attenuates GC progression in vitro and in vivo via sponging miR-197-3p

Hsa_circ_001988 has been identified as a tumor suppressor gene in several carcinomas. However, its expression pattern and role in gastric cancer (GC) have still remained elusive. This study aimed to explore the functions of hsa_circ_001988 in GC. Quantitative reverse transcription polymerase chain reaction assay was performed to assess the expressions of hsa_circ_001988, miR-197-3p, FBXW7, CCDC6, and U2AF65 in GC tissues. The correlation analysis was undertaken to find out the relationship between hsa_circ_001988 expression and clinicopathological factors. A series of cellular experiments were carried out to describe the effects of hsa_circ_001988 on GC in vivo and in vitro. Besides, RNA immunoprecipitation (RIP) assay was performed to verify the relationship among EIF4A3, U2AF65, and hsa_circ_001988. We first found that the expression of hsa_circ_001988 was decreased in 341 GC patients that was related to World Health Organization histological types, Lauren types, and tumor invasion depth (p < .05). Silencing of hsa_circ_001988 facilitated proliferation, colony formation, migration, and invasion of GC cells, while overexpression of hsa_circ_001988 reversed the effect on GC progression in vitro. Additionally, the results of subcutaneous xenotransplanted tumor model demonstrated that overexpressing hsa_circ_001988 significantly suppressed the subcutaneous tumor growth in vivo. Mechanistically, hsa_circ_001988 attenuated the miR-197-3p expression possibly due to its molecular sponge effect, and then, positively promoted FBXW7 expression. Afterwards, FBXW7 regulated the expressions of yes-associated protein 1, cyclinD1, CCDC6, and EMT-related proteins. Notably, RIP assay showed the enrichment relationship among EIF4A3, U2AF65, and hsa_circ_001988. Additionally, EIF4A3 or U2AF65 promoted cyclization of hsa_circ_001988 in GC. Hsa_circ_001988 inhibits the proliferation and metastasis of GC via modulating EIF4A3/U2AF65-mediated hsa_circ_001988/miR-197-3p/FBXW7 axis.

Principal component analysis of blood microRNA datasets facilitates diagnosis of diverse diseases

Early, ideally pre-symptomatic, recognition of common diseases (e.g., heart disease, cancer, diabetes, Alzheimer’s disease) facilitates early treatment or lifestyle modifications, such as diet and exercise. Sensitive, specific identification of diseases using blood samples would facilitate early recognition. We explored the potential of disease identification in high dimensional blood microRNA (miRNA) datasets using a powerful data reduction method: principal component analysis (PCA). Using Qlucore Omics Explorer (QOE), a dynamic, interactive visualization-guided bioinformatics program with a built-in statistical platform, we analyzed publicly available blood miRNA datasets from the Gene Expression Omnibus (GEO) maintained at the National Center for Biotechnology Information at the National Institutes of Health (NIH). The miRNA expression profiles were generated from real time PCR arrays, microarrays or next generation sequencing of biologic materials (e.g., blood, serum or blood components such as platelets). PCA identified the top three principal components that distinguished cohorts of patients with specific diseases (e.g., heart disease, stroke, hypertension, sepsis, diabetes, specific types of cancer, HIV, hemophilia, subtypes of meningitis, multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer’s disease, mild cognitive impairment, aging, and autism), from healthy subjects. Literature searches verified the functional relevance of the discriminating miRNAs. Our goal is to assemble PCA and heatmap analyses of existing and future blood miRNA datasets into a clinical reference database to facilitate the diagnosis of diseases using routine blood draws.

Analysis of lncRNA, miRNA and mRNA-associated ceRNA networks and identification of potential drug targets for drug-resistant non-small cell lung cancer

Background: Drug resistance to chemotherapeutic drugs or targeted medicines is an obstacle encountered in the treatment of non-small-cell lung cancer (NSCLC). However, the mechanisms of competing endogenous RNA (ceRNA) on the drug resistance in NSCLC are rarely reported. In this paper, the comprehensive expression profiles of lncRNAs and mRNAs in drug-resistant NSCLC cells were obtained by RNA sequencing.

Methods: The dysregulated lncRNAs, miRNAs and mRNAs in drug-resistant NSCLC cell lines were identified by RNA-sequencing and bioinformatics methods.

Results: A total of 39 dysregulated lncRNAs and 650 dysregulated mRNAs were identified between drug-resistant NSCLC cell lines and their parental cell lines. Additionally, 33 lncRNA-miRNA-mRNA pathways in the ceRNA network in drug-resistant NSCLC were constructed through bioinformatics methods and ceRNA regulatory rules. These comprised 12 dysregulated lncRNAs, five dysregulated miRNAs, and eight dysregulated mRNAs. In addition, lncRNA ATP2B1/miR-222-5p/TAB2 and lncRNA HUWE1/miR-222-5p/TAB2 were identified as potential ceRNA networks involved in drug resistance to NSCLC.

Conclusions: The current study provides a promising therapeutic strategy against the lncRNA-miRNA-mRNA ceRNA regulatory network for NSCLC treatment and deepens our comprehension of the ceRNA regulatory mechanisms related to drug resistance to NSCLC.

Long Noncoding RNA (lncRNA)-Mediated Competing Endogenous RNA Networks Provide Novel Potential Biomarkers and Therapeutic Targets for Colorectal Cancer

Colorectal cancer (CRC) is the third most common cancer and has a high metastasis and reoccurrence rate. Long noncoding RNAs (lncRNAs) play an important role in CRC growth and metastasis. Recent studies revealed that lncRNAs participate in CRC progression by coordinating with microRNAs (miRNAs) and protein-coding mRNAs. LncRNAs function as competitive endogenous RNAs (ceRNAs) by competitively occupying the shared binding sequences of miRNAs, thus sequestering the miRNAs and changing the expression of their downstream target genes. Such ceRNA networks formed by lncRNA/miRNA/mRNA interactions have been found in a broad spectrum of biological processes in CRC, including liver metastasis, epithelial to mesenchymal transition (EMT), inflammation formation, and chemo-/radioresistance. In this review, we summarize typical paradigms of lncRNA-associated ceRNA networks, which are involved in the underlying molecular mechanisms of CRC initiation and progression. We comprehensively discuss the competitive crosstalk among RNA transcripts and the novel targets for CRC prognosis and therapy.

LncRNA PART1 regulates colorectal cancer via targeting miR-150-5p/miR-520h/CTNNB1 and activating Wnt/β-catenin pathway

Numerous studies have reported that lncRNAs could play a significant role in carcinogenesis. PART1, as an identified lncRNA, was an oncogene in several cancers. However, the underling mechanism of PART1 regulating colorectal cancer remains unknown. qRT-PCR was used to measure relevant RNAs expression. CCK8 and colony formation were combined to evaluate cell proliferation. Tunel and flow cytometry were performed to access cell apoptosis. Wound healing and Transwell assay testified cell invasion and migration ability. Relevant protein expression level was measured via Western blot assay. TOP/FOP luciferase assay determined the activity of Wnt/β-catenin pathway. According to experiment findings, PART1 was up-regulated in CRC tissues and cell lines. Inhibition of PART1 hindered CRC cell proliferation, invasion and migration, while promoting CRC cell apoptosis. Experiments in vivo also validated this result. Mechanistically, PART1 sponged miR-150-5p/miR-520 h to up-regulate CTNNB1, thus activating Wnt/β-catenin pathway in CRC. In summary, PART1 could up-regulate CTNNB1 via sponging miR-150-5p/miR-520 h.