Decrease of miR-622 expression promoted the proliferation, migration and invasion of cholangiocarcinoma cells by targeting regulation of c-Myc

A review on the role of ncRNAs in the pathogenesis of cholangiocarcinoma

Cholangiocarcinoma is a rare tumor but a challenging cancer in terms of pathological changes, clinical manifestations and therapeutic options. Recent studies have provided evidence for participation of non-coding RNAs in the carcinogenic process of cholangiocarcinoma. We demonstrate the role of long non-coding RNAs, microRNAs and circular RNAs in the pathogenesis of cholangiocarcinoma and highlight their significant position as therapeutic targets and biomarkers for this type of cancer. We also list a number of molecular axes comprising these non-coding RNAs that represent potential targets for therapeutic options in cholangiocarcinoma, based on their significant roles in the regulation of cell proliferation, differentiation and apoptosis of these cells.

Circ_0001273 downregulation inhibits the growth, migration and glutamine metabolism of esophageal cancer cells via targeting the miR-622/SLC1A5 signaling axis

BACKGROUND

Esophageal cancer is a relatively rare cancer. However, its death rate is not to be taken lightly. Accumulating evidence indicates circular RNA (circRNA) is implicated in cancer development. The objective of this study was to unveil the role of circ_0001273 in esophageal cancer (EC).

METHODS

For expression analysis of circ_0001273, miR-622 and solute carrier family 1 member 5 (SLC1A5), quantitative real-time PCR (qPCR) and Western blot were conducted. Cell proliferation was evaluated by cell counting kit-8 (CCK-8), EdU and colony formation assays. Cell apoptosis and cell migration were investigated using flow cytometry assay and wound healing assay. Glutamine metabolism was assessed by glutamine consumption and glutamate production using matched kits. The predicted binding relationship between miR-622 and circ_0001273 or SLC1A5 was validated by dual-luciferase reporter assay. An in vivo xenograft model was established to determine the role of circ_0001273 on tumor growth.

RESULTS

Circ_0001273 was upregulated in EC tumor tissues and cells. Knockdown of circ_0001273 repressed EC cell proliferation, migration, epithelial-mesenchymal transition (EMT) and glutamine metabolism. Circ_0001273 knockdown also blocked tumor development in animal models. MiR-622 was targeted by circ_0001273, and its inhibition reversed the functional effects of circ_0001273 knockdown. SLC1A5 was a target gene of miR-622, and circ_0001273 targeted miR-622 to positively regulate SLC1A5 expression. The inhibitory effects of miR-622 enrichment on EC cell proliferation, migration, EMT and glutamine metabolism were recovered by SLC1A5 overexpression.

CONCLUSION

Circ_0001273 high expression contributed to EC progression via modulating the miR-622/SLC1A5 signaling axis.

The expression and function of miR-622 in a variety of tumors

Cancer is a heavy burden worldwide, with high morbidity and mortality rates. Cancer treatments currently involve surgical and nonsurgical approaches. Molecular targeted therapy is the latest breakthrough. miRNAs are small noncoding RNAs found in plants and animals that play a role in cancer and various diseases through influencing numerous biological processes, such as cell proliferation, apoptosis, the immune response, and drug resistance. One miRNA, miR-622, has been shown to regulate various pathways to influence disease processes. Abnormal miR-622 expression can promote or inhibit liver, colorectal, and breast cancers and other tumors, such as glioma. Herein, we reviewed the expression levels and clinical effects of miR-622 in various tumors and summarized its mechanisms and related molecules.

microRNAs and bone tumours: Role of tiny molecules in the development and progression of chondrosarcoma, of giant cell tumour of bone and of Ewing's sarcoma

The increasing interest on microRNAs (miRNAs), small non-coding RNA molecules containing about 22 nucleotides, about their biological functions led researchers to discover that they are actively involved in several biological processes. In the last decades, miRNAs become one of the most topic of cancer research. miRNAs, thanks to their function, are the perfect molecules to modulate multiple signaling pathways and gene expression in cancer, with the consequent capacity to modulate cancerous processes, such as cellular proliferation, invasion, metastasis and chemoresistance in various tumours. In the last years, several studies have demonstrated the role of miRNAs in their pathophysiology, but little we know about the underlying mechanism that lead to bone tumours like chondrosarcoma (COS), giant cell tumour of bone (GCTB) and Ewing sarcoma (EWS) to still be highly aggressive and resistant tumours. An exploration of the role of miRNAs in the biology of them will permit to researchers to find new molecular mechanisms that can be used to develop new and more effective therapies against these bone tumours. Here we present a comprehensive study of the latest discoveries which have been performed in relation to the role of miRNAs in the neoplastic processes which characterize COS, EWS and GCTB, demonstrating how these tiny molecules can act as tumour promoters or as tumour suppressors and how they can be used for improving therapeutic approaches.

The Role of microRNAs in Cholangiocarcinoma

Cholangiocarcinoma (CCA), an aggressive malignancy, is typically diagnosed at an advanced stage. It is associated with dismal 5-year postoperative survival rates, generating an urgent need for prognostic and diagnostic biomarkers. MicroRNAs (miRNAs) are a class of non-coding RNAs that are associated with cancer regulation, including modulation of cell cycle progression, apoptosis, metastasis, angiogenesis, autophagy, therapy resistance, and epithelial–mesenchymal transition. Several miRNAs have been found to be dysregulated in CCA and are associated with CCA-related risk factors. Accumulating studies have indicated that the expression of altered miRNAs could act as oncogenic or suppressor miRNAs in the development and progression of CCA and contribute to clinical diagnosis and prognosis prediction as potential biomarkers. Furthermore, miRNAs and their target genes also contribute to targeted therapy development and aid in the determination of drug resistance mechanisms. This review aims to summarize the roles of miRNAs in the pathogenesis of CCA, their potential use as biomarkers of diagnosis and prognosis, and their utilization as novel therapeutic targets in CCA.

miR-29b restrains cholangiocarcinoma progression by relieving DNMT3B-mediated repression of CDKN2B expression

Numerous studies have reported the important role of microRNAs (miRNAs) in human cancers. Although abnormal miR-29b expression has been linked to tumorigenesis in several cancers, its role in cholangiocarcinoma remains largely unknown. We found that miR-29b expression is frequently downregulated in human cholangiocarcinoma QBC939 cells and in clinical tumor samples. In cholangiocarcinoma patients, low miR-29b expression predicts poor overall survival. Overexpression of miR-29b in QBC939 cells inhibited proliferation, induced G1 phase cycle arrest, and promoted apoptosis. Methylation-specific PCR (MSP) analysis revealed a decreased methylation imprint at the promoter of the cell cycle inhibitor gene CDKN2B in cells overexpressing miR-29b. After identifying the DNA methyltransferase DNMT3B as a putative miR-29b target, luciferase reporter assays confirmed a suppressive effect of miR-29b on DNMT3B expression. Accordingly, we detected an inverse correlation between miR-29b and DNMT3B expression in clinical cholangiocarcinoma specimens. In QBC939 cells, DNMT3B overexpression promoted proliferation and inhibited apoptosis. DNMT3B silencing, in turn, led to increased CDKN2B expression. We also observed significant growth arrest in subcutaneous tumors formed in nude mice by QBC939 cells overexpressing miR-29b. These findings suggest miR-29b functions as a tumor suppressor in cholangiocarcinoma by relieving DNMT3B-mediated repression of CDKN2B expression.

LncRNA MNX1-AS1 promotes progression of intrahepatic cholangiocarcinoma through the MNX1/Hippo axis

Long non-coding RNAs (lncRNAs) have extremely complex roles in the progression of intrahepatic cholangiocarcinoma (ICC) and remain to be elucidated. By cytological and animal model experiments, this study demonstrated that the expression of lncRNA MNX1-AS1 was remarkably elevated in ICC cell lines and tissues, and was highly and positively correlated with motor neuron and pancreas homeobox protein 1 (MNX1) expression. MNX1-AS1 significantly facilitated the proliferation, migration, invasion, and angiogenesis in ICC cells in vitro, and remarkably promoted tumor growth and metastasis in vivo. Further study revealed that MNX1-AS1 promoted the expression of MNX1 via recruiting transcription factors c-Myc and myc-associated zinc finger protein (MAZ). Furthermore, MNX1 upregulated the expression of Ajuba protein via binding to its promoter region, and subsequently, Ajuba protein suppressed the Hippo signaling pathway. Taken together, our results uncovered that MNX1-AS1 can facilitate ICC progression via MNX1-AS1/c-Myc and MAZ/MNX1/Ajuba/Hippo pathway, suggesting that MNX1-AS1 may be able to serve as a potential target for ICC treatment.

Predictive Relevance of Circulating miR-622 in Patients with Newly Diagnosed and Recurrent High-Grade Serous Ovarian Carcinoma

BACKGROUND

Identifying patients with high-grade serous ovarian cancer (HGSOC) who will respond to treatment remains a clinical challenge. We focused on miR-622, a miRNA involved in the homologous recombination repair (HRR) pathway, and we assessed its predictive value in serum prior to first-line chemotherapy and at relapse.

METHODS

Serum miR-622 expression was assessed in serum prior to first-line platinum-based chemotherapy in a prospective multicenter study (miRNA Serum Analysis, miRSA, NCT01391351) and a retrospective cohort (Biological Resource Center, BRC), and was also studied at relapse. Progression-free survival (PFS) and overall survival (OS) were used as primary and secondary endpoints prior to first-line chemotherapy and OS as a primary endpoint at relapse.

RESULTS

The group with high serum miR-622 expression was associated with a significantly lower PFS (15.4 versus 24.4 months; adjusted HR 2.11, 95% CI 1.2 3.8, P = 0.015) and OS (29.7 versus 40.6 months; adjusted HR 7.68, 95% CI 2.2-26.2, P = 0.0011) in the miRSA cohort. In the BRC cohort, a high expression of miR-622 was also associated with a significantly lower OS (22.8 versus 35.9 months; adjusted HR 1.98, 95% CI 1.1-3.6, P = 0.026). At relapse, high serum miR-622 was associated with a significantly lower OS (7.9 versus 20.6 months; adjusted HR 3.15, 95% CI 1.4-7.2, P = 0.0062). Serum miR-622 expression is a predictive independent biomarker of response to platinum-based chemotherapy for newly diagnosed and recurrent HGSOC.

CONCLUSIONS

These results may open new perspectives for HGSOC patient stratification and monitoring of resistance to platinum-based and poly(ADP-ribose)-polymerase-inhibitor-maintenance therapies, facilitating better and personalized treatment decisions.

Hepatoprotective effects and mechanisms of Ixeris denticulate water extract on liver cirrhosis in experimental rat

BACKGROUND

To explore the protective effect and mechanisms of Ixeris denticulate water extract (IDWE) in the development of liver cirrhosis in experimental rat.

METHODS

Sixty rats were randomly divided into five groups: control group, model group and IDWE (2, 4 and 8 g/kg) treatment groups. Alanine transferase (ALT), aspartate transaminase (AST), albumin (ALB), tumor necrosis factor-alpha (TNF-α), Interleukin (IL)-6 and IL-8 in serum and superoxide dismutase (SOD), malondialdehyde (MDA) in liver tissue were evaluated, respectively. The liver index, liver morphology and liver histopathological analysis were detected as a supportive data. The liver protein expression of Bcl-2 and Bax were assessed by western blot, and NF-κB p65 protein expression was determined by immunohistochemistry analysis.

RESULTS

The result showed that a significantly decrease in the levels of serum AST, ALT and serum inflammatory factors TNF-α, IL-6 and IL-8 in IDWE-treated rats. The levels of serum ALB and SOD in liver tissue were markedly increased after IDWE treated, compared with model rats. Furthermore, IDWE-treated group also exhibited a down-regulated protein expression of NF-κB p65 and Bax, up-regulated Bcl-2 protein expression.

CONCLUSIONS

IDWE could effectively alleviate the course of liver cirrhosis in rat model, which may be a potent hepatoprotective agent in clinical therapy in the future.

A novel circular RNA, hsa-circ-0000211, promotes lung adenocarcinoma migration and invasion through sponging of hsa-miR-622 and modulating HIF1-α expression

Recently, several studies have evaluated the role of circular RNAs in the metastasis and development of multiple cancers. In our earlier microarray-based study, we had reported the aberrant expression of a novel circular RNA, hsa-circ-0000211 in lung adenocarcinoma (LAC) tissues. However, the roles of hsa-circ-0000211 in LAC have not been studied. Here hsa-circ-0000211 expression in the LAC tissues and cell lines was determined by quantitative real-time PCR (qRT-PCR). The function of hsa-circ-0000211 was evaluated by transwell assay and wound healing. Mechanisms of hsa-circ-0000211 was measured by luciferase reporter assay and western blot. Results revealed the expression of hsa-circ-0000211 in the human LAC tissues and LAC cell lines was higher than that in normal tissue and human lung normal epithelial cells, respectively. The knockdown of hsa-circ-0000211 could inhibit the migration and invasion properties of LAC. Furthermore, hsa-circ-0000211 promoted the migration and invasion of LAC by sponging miR-622. Moreover, hsa-circ-0000211 upregulated the HIF1-α expression by targeting miR-622. hsa-circ-0000211 promoted LAC cell migration and invasion by modulating the miR-622/HIF1-α network. Our study demonstrated that hsa-circ-0000211 can be a potential novel therapeutic target for LAC.

Upregulation of miR‑132‑3p in cholangiocarcinoma tissues: A study based on RT‑qPCR, The Cancer Genome Atlas miRNA sequencing, Gene Expression Omnibus microarray data and bioinformatics analyses

MicroRNAs (miRNAs/miRs) have been reported to be closely associated with numerous human diseases, including cholangiocarcinoma (CCA). However, the number of miRNAs known to be involved in CCA is limited, and the association between miR-132-3p and CCA remains unknown. In the present study, the clinical role of miR-132-3p and its potential signaling pathways were investigated by multiple approaches. Reverse transcription-quantitative PCR (RT-qPCR), CCA-associated Gene Expression Omnibus (GEO), ArrayExpress and Sequence Read Archive (SRA) miRNA-microarray or miRNA-sequencing data were screened, and meta-analyses were conducted, in order to calculate the receiver operating characteristic (ROC) curve and standardized mean difference (SMD). The predicted target genes of miR-132-3p were obtained from 12 online databases and were combined with the downregulated differentially expressed genes identified in the RNA-sequencing data of CCA. Gene Ontology annotation and pathway analysis were performed in WebGestalt. Protein-protein interaction analyses were conducted in STRING. The Cancer Genome Atlas (TCGA) mRNA expression profiles were used to validate the expression levels of hub genes at the mRNA level. The Human Protein Atlas was used to identify the protein expression levels of hub genes in CCA tissues and non-tumor biliary epithelium. The meta-analyses comprised 10 groups of RT-qPCR data, eight GEO microarray datasets and one TCGA miRNA-sequencing dataset. The SMD of miR-132-3p in CCA was 0.75 (95% CI: 0.25, 1.24), which indicated that miR-132-3p was overexpressed in CCA tissues. This finding was supported by a summary ROC value of 0.80 (95% CI: 0.76, 0.83). The pooled sensitivity and specificity were 0.81 (95% CI: 0.59, 0.93) and 0.71 (95% CI: 0.58, 0.81), respectively. The relative expression level of miR-132-3p in the early stage of CCA (stages I–II) was 6.8754±0.5279, which was markedly lower than that in the advanced stage (stages III–IVB), 7.3034±0.3267 (P=0.003). Consistently, the miR-132-3p level in low-grade CCA (grades G1-G2) was 6.7581±0.5297, whereas it was 7.1191±0.4651 in patients with high-grade CCA (grades G3-G4) (P=0.037). Furthermore, 555 potential target genes of miR-132-3p in CCA were mainly enriched in the ‘Focal Adhesion-PI3K-Akt-mTOR-signaling pathway’. In conclusion, upregulation of miR-132-3p may serve a pivotal role in the tumorigenesis and progression of CCA by targeting different pathways. Further in vitro and in vivo studies are required to support the current findings.

Screening for Differentially Expressed Circular RNAs in the Cartilage of Osteoarthritis Patients for Their Diagnostic Value

Background: Osteoarthritis (OA) is the most prevalent osteoarticular disease, which typically involves chronic cartilage degeneration and synovitis. The latest research shows that circular RNAs (circRNAs) play a role in the development of a variety of diseases, including osteoarthrosis. Purposes: The aim of this study was to explore the expression of circRNAs in OA chondrocytes and predict biomarkers for diagnosis. Materials and Methods: The circRNA expression profile was analyzed through use of the Gene Spring software V13.0; differentially expressed circRNAs were screened by comparing OA chondrocytes and normal articular chondrocytes. We validated the microarray data by quantitative real-time polymerase chain reaction analyses of OA chondrocytes and chondrocytes from normal controls. TargetScan software and miRanda software were used to predict networks of circRNA-miRNA interactions in cartilage. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analyses were applied to predict the functions of differentially expressed circRNAs. Results: Overall, 1380 circRNAs were differentially expressed between OA chondrocytes and normal articular chondrocytes (fold-change ≥2, p ≤ 0.05), including 215 that were upregulated and 1165 that were downregulated circRNAs. After analyzing the differentially expressed circRNA genes, the top 20 enriched GO entries and KEGG pathways were annotated. The hsa_circrna_0032131 was identified for further analysis. A circRNA-miRNA network was constructed to represent the 10 most likely target genes associated with the validated circRNA. Conclusions: Our research suggests that some of the differentially expressed circRNAs in OA chondrocytes compared to normal chondrocytes are etiologically associated with the pathological process of OA. It was found that hsa_circRNA_0032131 likely participates in the initiation and progression of OA and has potential as a diagnostic marker. Clinical Relevance: To analyze the difference of circRNA expression profiles between OA and normal controls and explore biomarkers for diagnosis.

miR-622 inhibits angiogenesis by suppressing the CXCR4-VEGFA axis in colorectal cancer

Angiogenesis is essential for tumor metastasis. Our previous study has revealed that miR-622 inhibits colorectal cancer (CRC) metastasis. Here, we aimed to explore the effects and potential molecular mechanisms of action of miR-622 on angiogenesis. We found that overexpression of miR-622 inhibited CRC angiogenesis in vitro, according to suppression of proliferation, migration, tube formation, and invasiveness of human umbilical vein endothelial cells (HUVECs) treated with a tumor cell-conditioned medium derived from Caco-2 or HT-29 cells. Likewise, enhanced miR-622 expression suppressed CRC angiogenesis in vivo as determined by the measurement of Ki67 and VEGFA levels and microvessel density (by immunostaining). CXCR4, encoding a positive regulator of vascular endothelial growth factor A (VEGFA), was shown to be a direct target of miR-622. Overexpression of CXCR4 attenuated the inhibition of VEGFA expression by miR-622 and reversed the loss of tumor angiogenesis caused by miR-622. Taken together, these data show that miR-622 inhibits CRC angiogenesis by suppressing the CXCR4-VEGFA signaling axis, which represents a promising target for developing a new therapeutic strategy against CRC.

Forskolin-mediated BeWo cell fusion involves down-regulation of miR-92a-1-5p that targets dysferlin and protein kinase cAMP-activated catalytic subunit alpha

PROBLEM

To study the role of miRNA(s) during trophoblastic BeWo cell fusion.

METHOD OF STUDY

Changes in miRNA(s) profile of BeWo cells treated with forskolin were analyzed using Affymetrix miRNA microarray platform. Down-regulated miRNA, miR-92a-1-5p, was overexpressed in BeWo cells followed by forskolin treatment to understand its relevance in the process of BeWo cell fusion by desmoplakin I+II staining and hCG secretion by ELISA. Predicted targets of miR-92a-1-5p were also confirmed by qRT-PCR/Western blotting.

RESULTS

The miRNA profiling of BeWo cells after forskolin (25 μmol/L) treatment identified miR-92a-1-5p as the most significantly down-regulated miRNA both at 24 and 48 hours time points. Overexpression of miR-92a-1-5p in these cells led to a significant decrease in forskolin-mediated cell fusion and hCG secretion. miRNA target prediction software, TargetScan, revealed dysferlin (DYSF) and protein kinase cAMP-activated catalytic subunit alpha (PRKACA), as target genes of miR-92a-1-5p. Overexpression of miR-92a-1-5p in BeWo cells showed reduction in forskolin-induced transcripts for DYSF and PRKACA. Further, reduction in DYSF (~2.6-fold) at protein level and PRKACA-encoded protein kinase A catalytic subunit alpha (PKAC-α; ~1.6-fold) were also observed.

CONCLUSION

These observations suggest that miR-92a-1-5p regulates forskolin-mediated BeWo cell fusion and hCG secretion by regulating PKA signaling pathway and dysferlin expression.