miR-490: A potential biomarker and therapeutic target in cancer and other diseases

DNA methylation biomarkers accurately detect esophageal cancer prior and post neoadjuvant chemoradiation

BACKGROUND

Esophageal cancer (ECa) is associated with high mortality, mostly due to late diagnosis, precluding curativeintent surgery. Hence, neoadjuvant chemoradiation (ChRT) is recommended in most patients regardless of histological subtype. A proportion of these patients, however, achieve complete disease remission and might be spared of radical surgery. The lack of reliable, minimally invasive biomarkers able to detect post-ChRT disease persistence is, nonetheless, a major drawback. We have previously shown that miRNA promotor methylation enables accurate cancer detection in tissues and liquid biopsies but has been seldom explored in ECa patients.

AIMS

Herein, we sought to unveil and validate novel candidate biomarkers able to detect ECa prior and post ChRT.

MATERIALS AND METHODS

Promoter methylation of miR129-2, miR124-3 and ZNF569 was assessed, using quantitative methylation-specific PCR (qMSP), in tissue samples from normal esophagus, treatment-naïve and post-ChRT ECa, as well as in liquid biopsies from ECa patients.

RESULTS

All genes disclosed significantly different promoter methylation levels between ECa and normal esophagus, accurately detecting post-ChRT disease, especially for adenocarcinoma. Remarkably, miR129-2_me /ZNF569_me methylation panel identified ECa in liquid samples with 53% sensitivity and 87% specificity.

DISCUSSION

MiR129-2_me , miR124-3_me and ZNF569_me accurately discriminate ECa, either pre- or post-ChRT, from normal tissue, enabling ECa detection. Furthermore, circulalting methylation-based biomarkers are promising minimally invasive tools to detect post-ChRT residual ECa.

CONCLUSION

Overall, our results encourage the use of miRNA methylation biomarkers as accurate ECa detection tools as a novel approach for ChRT response monitoring.

Emodin ameliorates renal injury and fibrosis via regulating the miR-490-3p/HMGA2 axis

Renal fibrosis is a major pathological feature of chronic kidney disease (CKD). While emodin is reported to elicit anti-fibrotic effects on renal injury, little is known about its effects on microRNA (miRNA)-modulated mechanisms in renal fibrosis. In this study, we established a unilateral ureteral obstruction (UUO) model and a transforming growth factor (TGF)-β1-induced normal rat renal tubular epithelial cell line (NRK-52E) model to investigate the protective effects of emodin on renal fibrosis and its miRNA/target gene mechanisms. Dual-luciferase assay was performed to confirm the direct binding of miRNA and target genes in HEK293 cells. Results showed that oral administration of emodin significantly ameliorated the loss of body weight and the increase in physicochemical parameters, including serum uric acid, creatinine, and urea nitrogen in UUO mice. Inflammatory cytokines, including tumor necrosis factor-α, monocyte chemoattractant protein-1, and interleukin (IL)-1β, but not IL-6, were down-regulated by emodin administration. Emodin decreased the expression levels of TGF-β1 and fibrotic-related proteins, including alpha-smooth muscle actin, Collagen IV, and Fibronectin, and increased the expression of E-cadherin. Furthermore, miR-490-3p was decreased in UUO mice and negatively correlated with increased expression of high migration protein A2 (HMGA2). We further confirmed HMGA2 was the target of miR-490-3p. Transfection of miR-490-3p mimics decreased, while transfection of miR-490-3p inhibitors increased fibrotic-related proteins and HMGA2 expression levels in TGF-β1-induced NRK-52E cells. Furthermore, transfection of miR-490-3p mimics enhanced the anti-fibrotic effects of emodin, while transfection of miR-490-3p inhibitors abolished the protective effects of emodin. Thus, as a novel target of emodin that prevents renal fibrosis in the HMGA2-dependent signaling pathway, miR-490-3p has potential implications in CKD pathology.

MiR-507 inhibits the progression of gastric carcinoma via targeting CBX4-mediated activation of Wnt/β-catenin and HIF-1α pathways

PURPOSE

Gastric carcinoma (GC) is a common malignant disease with high morbidity and mortality. MiR-507 has been confirmed as a tumor inhibitor which can suppress the progression of multiple cancers while its role in GC remains unknown.

METHODS

In this study, the expression levels of miR-507 in the GC tissues and cells were observed by qRT-PCR, and CCK-8 assay, transwell asssay and TUNEL assay were used to observe the function of miR-507 on GC. The miRNA database and dual-luciferase reporter assay were used to investigate the downstream target of miR-507. Moreover, the activities of Wnt/β-catenin and HIF-1α pathways were observed by western blot.

RESULTS

The results showed that miR-507 was significantly downregulated in GC tissues and cell lines, and miR-507 upregulation effectively inhibited the proliferation and invasion and induced the apoptosis of GC cells. CBX4 was a downstream target of miR-507, and CBX4 could reverse the effects of miR-507 on the GC cells. Moreover, it was determined that miR-507 could inhibit CBX4 expression to suppress the activation of Wnt/β-catenin and HIF-1α pathways.

CONCLUSIONS

In conclusion, it suggests that miR-507 could inhibit the progression of GC via regulating CBX4-mediated activation of Wnt/β-catenin and HIF-1α pathways.

Noncoding RNAs and their therapeutics in paclitaxel chemotherapy: Mechanisms of initiation, progression, and drug sensitivity

The identification of agents that can reverse drug resistance in cancer chemotherapy, and enhance the overall efficacy is of great interest. Paclitaxel (PTX) belongs to taxane family that exerts an antitumor effect by stabilizing microtubules and inhibiting cell cycle progression. However, PTX resistance often develops in tumors due to the overexpression of drug transporters and tumor-promoting pathways. Noncoding RNAs (ncRNAs) are modulators of many processes in cancer cells, such as apoptosis, migration, differentiation, and angiogenesis. In the present study, we summarize the effects of ncRNAs on PTX chemotherapy. MicroRNAs (miRNAs) can have opposite effects on PTX resistance (stimulation or inhibition) via influencing YES1, SK2, MRP1, and STAT3. Moreover, miRNAs modulate the growth and migration rates of tumor cells in regulating PTX efficacy. PIWI-interacting RNAs, small interfering RNAs, and short-hairpin RNAs are other members of ncRNAs regulating PTX sensitivity of cancer cells. Long noncoding RNAs (LncRNAs) are similar to miRNAs and can modulate PTX resistance/sensitivity by their influence on miRNAs and drug efflux transport. The cytotoxicity of PTX against tumor cells can also be affected by circular RNAs (circRNAs) and limitation is that oncogenic circRNAs have been emphasized and experiments should also focus on onco-suppressor circRNAs.

MiR-223 Promotes Tumor Progression via Targeting RhoB in Gastric Cancer

Gastric cancer (GC) is among the most prevalent causes of cancer-related death globally. MiR-223 has been implicated in a variety of cellular mechanisms linked to cancer progression. However, the miR-223 expressions and its function in GC are unknown. We discovered that miR-223 expression was raised in GC tissues in comparison with nearby normal tissues in this investigation. Additionally, multiplied miR-223 expression was strongly linked with TNM stage (p=0.022), live metastasis (p=0.004),lymph node metastasis (p=0.004),and Borrmann type and was associated with an unfavorable prognostic for patients with GC. Furthermore, suppressing miR-223 significantly increased cell death and prevented cell migration and invasion in vitro. Additionally, miR-223 silencing decreased tumor development in vivo. Additionally, we discovered that miR-223 enhanced GC development by specifically targeting RhoB. In summary, our findings reveal that miR-223 increases tumor progression in GC by targeting RhoB, suggesting that it could serve to be a potential biomarker for the prediction of the disease.

The role of non-coding RNA in the diagnosis and treatment of Helicobacter pylori-related gastric cancer, with a focus on inflammation and immune response

Helicobacter pylori (H. pylori) is one of the globally recognized causative factors of gastric cancer (GC). Currently, no definite therapy and drugs for H. pylori-related GC have been widely acknowledged although H. pylori infection could be eradicated in early stage. Inflammation and immune response are spontaneous essential stages during H. pylori infection. H pylori may mediate immune escape by affecting inflammation and immune response, leading to gastric carcinogenesis. As an important component of transcriptome, non-coding RNAs (ncRNAs) have been proven to play crucial roles in the genesis and development of H. pylori-induced GC. This review briefly described the effects of ncRNAs on H. pylori-related GC from the perspective of inflammation and immune response, as well as their association with inflammatory reaction and immune microenvironment. We aim to explore the potential of ncRNAs as markers for the early diagnosis, prognosis, and treatment of H. pylori-related GC. The ncRNAs involved in H. pylori-related GC may all hold promise as novel therapeutic targets for immunotherapy.

MicroRNA-100 inhibits breast cancer cell proliferation, invasion and migration by targeting FOXA1

MicroRNAs (miRNAs/miRs) are highly conserved single-stranded small non-coding RNAs, which are involved in the physiological and pathological processes of breast cancer, and affect the prognosis of patients with breast cancer. The present study used the Gene Expression Omnibus (GEO)2R tool to detect miR-100 expression in breast cancer tissues obtained from GEO breast cancer-related datasets. Bioinformatics analysis revealed that miR-100 expression was downregulated in different stages, grades and lymph node metastasis stages of breast cancer, and patients with high miR-100 expression had a more favorable prognosis. Based on these analyses, Cell Counting Kit-8, wound healing and Transwell assays were performed, and the results demonstrated that overexpression of miR-100 inhibited the proliferation, migration and invasion of breast cancer cells. To verify the tumor-suppressive effect of miR-100 in breast cancer, the LinkedOmics and PITA databases were used to assess the association between miR-100 and forkhead box A1 (FOXA1). The results demonstrated that miR-100 had binding sites within the FOXA1 gene, and FOXA1 expression was negatively associated with miR-100 expression in breast cancer tissues. Similarly, a negative association was observed between miR-100 and FOXA1 expression, using the StarBase V3.0 database. The association between miR-100 and FOXA1 was further verified via reverse transcription-quantitative PCR and western blot analyses, and the dual-luciferase reporter assay. The results demonstrated that miR-100 targeted the 3′-untranslated region of FOXA1 in breast cancer cells. Furthermore, rescue experiments were performed to confirm whether miR-100 exerts its antitumor effects by regulating FOXA1. The results demonstrated that overexpression of FOXA1 promoted the proliferation, migration and invasion of breast cancer cells; thus, the antitumor effects of miR-100 in breast cancer were reversed following overexpression of FOXA1. Taken together, the results of the present study suggest that miR-100 inhibits the proliferation, migration and invasion of breast cancer cells by targeting FOXA1 expression. These results may provide a novel insight and an experimental basis for identifying effective therapeutic targets of high specificity for breast cancer.

Role of miR-490-3p in blocking bladder cancer growth through targeting the RNA-binding protein PCBP2

MiR-490-3p is regarded as a tumor suppressor in many cancers, but whether miR-490-3p is involved in the development of bladder cancer remains unknown. BALB/c nude mice (male, 15-20 g) were used to investigate the role of MiR-490-3p in bladder cancer. The relationship between miR-490-3p and PCBP2 involved in bladder cancer regulation were determined. Cell viability, proliferation, and cell cycle were estimated by cell counting kit-8 (CCK-8) assay, 5-bromo-2'-deoxyuridine (BrdU) detection, and flow cytometry analysis, respectively. In animal experiments, lentivirus was transfected into bladder cancer cells to overexpress miR-490-3p, which were then injected into mice and the change of tumor volume was assessed. Principal findings: The expression of MiR-490-3p was decreased in bladder cancer cells. Overexpression of miR-490-3p inhibited bladder cancer cell viability and proliferation. Moreover, overexpression of miR-490-3p caused cell cycle arrest in bladder cancer cells. The inhibitory effect of miR-490-3p on bladder cancer cells growth could be counteracted by enhancing PCBP2 expression. In vivo, bladder cancer growth in mice was blocked by miR-490-3p upregulation. MiR-490-3p suppressed bladder cancer growth and bladder cancer cell proliferation by down-regulating PCBP2 expression.

The Role of microRNAs in Pulp Inflammation

The dental pulp can be affected by thermal, physical, chemical, and bacterial phenomena that stimulate the inflammatory response. The pulp tissue produces an immunological, cellular, and vascular reaction in an attempt to defend itself and resolve the affected tissue. The expression of different microRNAs during pulp inflammation has been previously documented. MicroRNAs (miRNAs) are endogenous small molecules involved in the transcription of genes that regulate the immune system and the inflammatory response. They are present in cellular and physiological functions, as well as in the pathogenesis of human diseases, becoming potential biomarkers for diagnosis, prognosis, monitoring, and safety. Previous studies have evidenced the different roles played by miRNAs in proinflammatory, anti-inflammatory, and immunological phenomena in the dental pulp, highlighting specific key functions of pulp pathology. This systematized review aims to provide an understanding of the role of the different microRNAs detected in the pulp and their effects on the expression of the different target genes that are involved during pulp inflammation.

Magic and mystery of microRNA-32

MicroRNAs (miRNAs) are a group of endogenous, small (∼22 nts in length) noncoding RNA molecules that function specifically by base pairing with the mRNA of genes and regulate gene expression at the post-transcriptional level. Alterations in miR-32 expression have been found in numerous diseases and shown to play a vital role in cell proliferation, apoptosis, oncogenesis, invasion, metastasis and drug resistance. MiR-32 has been documented as an oncomiR in the majority of related studies but has been also verified as a tumour suppressor miRNA in conflicting reports. Moreover, it has a crucial role in metabolic and cardiovascular disorders. This review provides an in-depth look into the most recent finding regarding miR-32, which is involved in the expression, regulation and functions in different diseases, especially tumours. Additionally, this review outlines novel findings suggesting that miR-32 may be useful as a noninvasive biomarker and as a targeted therapeutic in several diseases.

MicroRNA-490-3p and -490-5p in carcinogenesis: Separate or the same goal?

MicroRNA (miR)-490-3p and miR-490-5p, located on chromosome 7q33, are two independent mature products of miR-490 exerting distinct effects on tumor progression. miR-490-3p and miR-490-5p possess antitumor properties. miR-490-3p dysfunction has been associated with malignancies including colorectal cancer, while the abnormal function of miR-490-5p has been more considerably associated with bladder cancer (for example). At present, there are 30 and 11 target genes of miR-490-3p and miR-490-5p, respectively, that have been experimentally verified, of which the cyclin D1 (CCND1) gene is a common target. Through these target genes, miR-490-3p and miR-490-5p are involved in 7 and 3 signaling pathways, respectively, of which only 2 are shared regulatory signaling pathways. The present review introduces two competing endogenous RNA (ceRNA) regulatory networks centered on miR-490-3p and miR-490-5p. These networks may be important promoters of tumor cell proliferation, invasiveness, metastatic potential and apoptosis. Unlike miR-490-5p, miR-490-3p plays a unique role in promoting cancer. However, both are promising molecular markers for early cancer diagnosis and prognosis. In addition, miR-490-3p was also found to be associated with the chemical resistance of cisplatin and paclitaxel. The present review focuses on the abnormal expression of miR-490-3p and miR-490-5p in different tumor types, and their complex ceRNA regulatory networks. The clinical value of miR-490-3p and miR-490-5p in cancer diagnosis, prognosis and treatment is also clarified, and an explanation for the opposing effects of miR-490-3p in tumor research is provided.

An updated overview and classification of bioinformatics tools for MicroRNA analysis, which one to choose?

The term 'MicroRNA' (miRNA) refers to a class of small endogenous non-coding RNAs (ncRNAs) regenerated from hairpin transcripts. Recent studies reveal miRNAs' regulatory involvement in essential biological processes through translational repression or mRNA degradation. Recently, there is a growing body of literature focusing on the importance of miRNAs and their functions. In this respect, several databases have been developed to manage the dispersed data produced. Therefore, it is necessary to know the parameters and characteristics of each database to benefit their data. Besides, selecting the correct database is of great importance to scientists who do not have enough experience in this field. A comprehensive classification along with an explanation of the information contained in each database leads to facilitating access to these resources. In this regard, we have classified relevant databases into several categories, including miRNA sequencing and annotation, validated/predicted miRNA targets, disease-related miRNA, SNP in miRNA sequence or target site, miRNA-related pathways, or gene ontology, and mRNA-miRNA interactions. Hence, this review introduces available miRNA databases and presents a convenient overview to inform researchers of different backgrounds to find suitable miRNA-related bioinformatics web tools and relevant information rapidly.