MicroRNA-1 acts as a tumor suppressor microRNA by inhibiting angiogenesis-related growth factors in human gastric cancer

LncRNA UCA1 promotes vasculogenic mimicry by targeting miR-1-3p in gastric cancer

Long noncoding RNA urothelial carcinoma-associated 1 (UCA1) has been implicated in several tumors. UCA1 promotes cell proliferation, migration, and invasion of gastric cancer (GC) cells, but the molecular mechanism has not been fully elucidated. This study revealed the oncogenic effects of UCA1 on cell growth and invasion. Furthermore, UCA1 expression was significantly correlated with the overall survival of GC patients, and the clinicopathological indicators, including tumor size, depth of invasion, lymph node metastasis, and TNM stage. Additionally, miR-1-3p was identified as a downstream target of UCA1, which was negatively regulated by UCA1. MiR-1-3p inhibited cell proliferation and vasculogenic mimicry (VM), and induced cell apoptosis by upregulating BAX, BAD, and tumor suppressor TP53 expression levels. Moreover, miR-1-3p almost completely reversed the oncogenic effect caused by UCA1, including cell growth, migration, and VM formation. This study also confirmed that UCA1 promoted tumor growth in vivo. In this study, we also revealed the correlation between UCA1 and VM formation, which is potentially crucial for tumor metastasis. Meanwhile, its downstream target miR-1-3p inhibited VM formation in GC cells. In summary, these findings indicate that the UCA1/miR-1-3p axis is a potential target for GC treatment.

The clinical prognostic significance of miR-140-5p expression in patients with cancer: A Meta and Bioinformatic analysis

The prognostic value of microRNA-140-5p (miR-140-5p) expression in cancer patients has been investigated, but with inconsistent results. This meta-analysis aims to determine the prognostic significance of miR-140-5p expression in patients with various malignancies. A comprehensive literature search was conducted using PubMed, Web of Science, ProQuest, Cochrane, and Google Scholar to identify relevant studies published before June 2023. Pooled hazard ratios (HR) and odds ratios (OR) with 95 % confidence intervals (CI) were calculated to assess the prognostic importance and clinicopathological features of miR-140-5p in overall survival (OS) and disease-free survival (DFS) of cancer patients, respectively. The CancerMIRNome database and other OS analysis webservers were utilized to explore the prognostic value and expression profile of miR-140-5p. A total of 17 studies were included in the final analysis. The results demonstrated that decreased miR-140-5p expression was significantly associated with inferior OS (pooled HR 0.63; 95 % CI, 0.51-0.79; p < 0.001) and DFS (pooled HR 0.40; 95 % CI, 0.25-0.64; p < 0.001). Pooled ORs indicated a significant correlation between reduced miR-140-5p expression and positive lymph node metastasis (LNM; OR = 3.42; 95 % CI, 2.36-4.94; p < 0.001), advanced tumor stage (OR = 2.80; 95 % CI, 2.07-3.78; p < 0.001), and positive distant metastasis (DM; OR = 10.81; 95 % CI, 3.31-35.30; p < 0.001). No significant associations were observed between miR-140-5p expression and gender (OR = 0.94; 95 % CI, 0.70-1.28; p = 0.70), age (OR = 1.31; 95 % CI, 0.99-1.74; p = 0.06), tumor size (OR = 1.55; 95 % CI, 0.77-3.10; p = 0.22), and histological grade (OR = 1.20; 95 % CI, 0.46-3.10; p = 0.71). Subgroup analyses revealed that decreased miR-140-5p expression was associated with shorter OS in subgroups based on sample size (<100 or >100), tumor origin (GI or non-GI), and cancer type (GC/CRC). Bioinformatic analysis supported the finding that miR-140-5p was downregulated in most tumor tissues, and its reduced expression was linked to poor prognosis in patients with multiple malignancies. The prognostic significance of miR-140-5p in predicting reduced OS and DFS suggests that measuring miR-140-5p expression levels before treatment could serve as a valuable biomarker for identifying cancer patients with an unfavorable prognosis and improving clinical management.

The role of microRNAs in the gastric cancer tumor microenvironment

BACKGROUND

Gastric cancer (GC) is one of the deadliest malignant tumors with unknown pathogenesis. Due to its treatment resistance, high recurrence rate, and lack of reliable early detection techniques, a majority of patients have a poor prognosis. Therefore, identifying new tumor biomarkers and therapeutic targets is essential. This review aims to provide fresh insights into enhancing the prognosis of patients with GC by summarizing the processes through which microRNAs (miRNAs) regulate the tumor microenvironment (TME) and highlighting their critical role in the TME.

MAIN TEXT

A comprehensive literature review was conducted by focusing on the interactions among tumor cells, extracellular matrix, blood vessels, cancer-associated fibroblasts, and immune cells within the GC TME. The role of noncoding RNAs, known as miRNAs, in modulating the TME through various signaling pathways, cytokines, growth factors, and exosomes was specifically examined. Tumor formation, metastasis, and therapy in GC are significantly influenced by interactions within the TME. miRNAs regulate tumor progression by modulating these interactions through multiple signaling pathways, cytokines, growth factors, and exosomes. Dysregulation of miRNAs affects critical cellular processes such as cell proliferation, differentiation, angiogenesis, metastasis, and treatment resistance, contributing to the pathogenesis of GC.

CONCLUSIONS

miRNAs play a crucial role in the regulation of the GC TME, influencing tumor progression and patient prognosis. By understanding the mechanisms through which miRNAs control the TME, potential biomarkers and therapeutic targets can be identified to improve the prognosis of patients with GC.

MicroRNA-1 targets ribosomal protein genes to regulate the growth, development and reproduction of Schistosoma japonicum

Eggs laid by mature female schistosomes are primarily responsible for the pathogenesis of schistosomiasis and critical for transmission. Consequently, elucidating the mechanism of sexual maturation as well as egg production may lead to new strategies for the control of schistosomiasis. MicroRNAs (miRNAs) are involved in multiple biological processes including reproduction in many organisms, yet their roles have not been well characterized in schistosomes. Here, we investigated microRNA-1 (miR-1), which was downregulated gradually in both male and female Schistosoma japonicum after they reached sexually maturity. The expression of miR-1, as shown with quantitative reverse transcription PCR (qRT-PCR), was lower in the reproductive organs of adult females compared with the somatic tissues. Overexpression of miR-1 in adult worms destroyed the morphological architecture of reproductive organs and reduced the subsequent oviposition, which may be due to the activation of apoptosis pathways. Through in silico analysis, 34 potential target genes of miR-1 were identified, including five ribosomal protein genes, called rp-s13, rp-l7ae, rp-l14, rp-l11 and rp-s24e. In vitro dual-luciferase reporter gene assays and miRNA overexpression experiments further validated that these ribosomal protein genes were directly regulated by miR-1. In contrast to the gene expression of miR-1, qRT-PCR and in situ hybridization experiments demonstrated these ribosomal protein genes were enriched in the sexual organs of adult females. Using RNA interference to silence the ribosomal protein genes in different developmental stages in a mouse model system, we demonstrated that these miR-1 target genes not only participated in the reproductive development of S. japonicum, but also were required for the growth and survival of the parasite in the early developmental stages. Taken together, our data suggested that miR-1 may affect the growth, reproduction and oviposition of S. japonicum by targeting the ribosomal protein genes, which provides insights for exploration of new anti-schistosome strategies.

Hypoxic glioma cell-secreted exosomal circ101491 promotes the progression of glioma by regulating miR-125b-5p/EDN1

Hypoxia and exosomes play important roles in the occurrence and development of glioma. While circRNAs are involved in biological processes of various tumors, the mechanism underlying exosome-dependent regulatory effects of circRNAs on the progression of glioma under hypoxia is unclear. Results suggested that circ101491 was overexpressed in tumor tissues and plasma exosomes of glioma patients, while the overexpression of circ101491 was closely related to the differentiation degree and TNM staging of the patients. Moreover, circ101491 overexpression promoted viability, invasion and migration of glioma cells both in vivo and in vitro; the above regulatory effects can be reversed by inhibition of circ101491 expression. Mechanistic studies revealed that circ101491 upregulated EDN1 expression through sponging miR-125b-5p, thus facilitating glioma progression. In summary, hypoxia could promote circ101491 overexpression in glioma cell-derived exosomes, and circ101491/miR-125b-5p/EDN1 regulatory axis might be implicated in the malignant progression of glioma.

Endothelin-3 is epigenetically silenced in endometrioid endometrial cancer

Purpose

Changes in the activity of endothelins and their receptors may promote neoplastic processes. They can be caused by epigenetic modifications and modulators, but little is known about endothelin-3 (EDN3), particularly in endometrial cancer. The aim of the study was to determine the expression profile of endothelin family and their interactions with miRNAs, and to assess the degree of EDN3 methylation.

Methods

The study enrolled 45 patients with endometrioid endometrial cancer and 30 patients without neoplastic changes. The expression profile of endothelins and their receptors was determined with mRNA microarrays and RT-qPCR. The miRNA prediction was based on the miRNA microarray experiment and the mirDB tool. The degree of EDN3 methylation was assessed by MSP.

Results

EDN1 and EDNRA were overexpressed regardless of endometrial cancer grade, which may be due to the lack of regulatory effect of miR-130a-3p and miR-485-3p, respectively. In addition, EDN3 and EDNRB were significantly downregulated.

Conclusion

The endothelial axis is disturbed in endometrioid endometrial cancer. The observed silencing of EDN3 activity may be mainly due to DNA methylation.

Restoration of miR-648 overcomes 5-FU-resistance through targeting ET-1 in gastric cancer cells in-vitro

BACKGROUND

Endothelin-1 (ET-1) is a peptide overexpressed in gastric cancer (GC) and linked to carcinogenesis and resistance to chemotherapy. Applying microRNAs (miRNAs/miRs) to downregulate ET-1 and reverse resistance to commonly used chemotherapy drugs such as 5-fluorouracil (5-FU) is practical.

METHODS

The current study sought to evaluate the miR-648 expression in GC and any plausibility of its replacement, either with or without the combination of chemo agents to downregulate ET-1 expression through interaction with its target gene. To this end, miR-648 and ET-1 expression levels were assessed in GC tissues and adjacent non-tumor tissues driven from 65 patients who had already undergone surgery, fifteen of which had received 5-FU before surgery. The impact of miR-648 and chemo agents on ET-1 expression was measured using qPCR and Western blotting. Further, an MTT assay was conducted to assess its association with cell viability. Ultimately, the association of miR-648 and ET-1 with clinicopathological characteristics was evaluated.

RESULTS

The current study revealed that miR-648 was considerably down-regulated, while ET-1 was substantially up-regulated in patients with GC. The 5-FU caused a significant increase in miR-648 and reduced ET-1 expression. It was also determined that overexpression of miR-648 suppressed ET-1 production, notably when combined with 5-FU, leading to survival reduction. These results further showed that miR-648 replacement could sensitize chemoresistant GC cells. Besides, a significant association between ET-1 and miR-648 with clinicopathological features was discovered CONCLUSIONS: miR-648 replacement may serve as a potential oncosuppressive therapeutic approach that warrants further investigation to translate into an effective GC treatment.

The Molecular Roles and Clinical Implications of Non-Coding RNAs in Gastric Cancer

Gastric cancer (GC) is one of the most common malignancies in the world. It is also the fifth most common cancer in China. In recent years, a large number of studies have proved that non-coding RNAs (ncRNAs) can regulate cell proliferation, invasion, metastasis, apoptosis, and angiogenesis. NcRNAs also influence the therapeutic resistance of gastric cancer. NcRNAs mainly consist of miRNAs, lncRNAs and circRNAs. In this paper, we summarized ncRNAs as biomarkers and therapeutic targets for gastric cancer, and also reviewed their role in clinical trials and diagnosis. We sum up different ncRNAs and related moleculars and signaling pathway in gastric cancer, like Bcl-2, PTEN, Wnt signaling. In addition, the potential clinical application of ncRNAs in overcoming chemotherapy and radiotherapy resistance in GC in the future were also focused on.

Issues of origin, morphology and clinical significance of tumor microvessels in gastric cancer

Gastric cancer (GC) remains a serious oncological problem, ranking third in the structure of mortality from malignant neoplasms. Improving treatment outcomes for this pathology largely depends on understanding the pathogenesis and biological characteristics of GC, including the identification and characterization of diagnostic, prognostic, predictive, and therapeutic biomarkers. It is known that the main cause of death from malignant neoplasms and GC, in particular, is tumor metastasis. Given that angiogenesis is a critical process for tumor growth and metastasis, it is now considered an important marker of disease prognosis and sensitivity to anticancer therapy. In the presented review, modern concepts of the mechanisms of tumor vessel formation and the peculiarities of their morphology are considered; data on numerous factors influencing the formation of tumor microvessels and their role in GC progression are summarized; and various approaches to the classification of tumor vessels, as well as the methods for assessing angiogenesis activity in a tumor, are highlighted. Here, results from studies on the prognostic and predictive significance of tumor microvessels in GC are also discussed, and a new classification of tumor microvessels in GC, based on their morphology and clinical significance, is proposed for consideration.

Effect of Helicobacter pylori Eradication on Epigenetic Changes in Gastric Cancer-related Genes

It is known that gastric carcinogenesis results from the progressive changes from chronic gastritis to gastric atrophy, intestinal metaplasia, dysplasia, and invasive carcinoma. Several genetic and epigenetic alterations are involved in this process, and Helicobacter pylori (H. pylori) infection is believed to induce the initiation and progression of these steps. From an epigenetic point of view, H. pylori induces hypermethylation of genes involved in the development of gastric cancer and regulates the expression of various microRNAs (miRNAs). These H. pylori-related epigenetic changes are accumulated not only at the site of neoplasm but also in the adjacent non-cancerous gastric mucosa. Thereby, a state vulnerable to gastric cancer known as an epigenetic field defect is formed. H. pylori eradication can have an effective chemopreventive effect in gastric carcinogenesis. However, the molecular biological changes that occur in the stomach environment during H. pylori eradication have not yet been established. Several studies have reported that H. pylori eradication can restore infection-related changes, especially epigenetic alterations in gastric cancer-related genes, but some studies have shown otherwise. Simply put, it appears that the recovery of methylated gastric cancer-related genes and miRNAs during H. pylori eradication may vary among genes and may also differ depending on the histological subtype of the gastric mucosa. In this review, we will discuss the potential mechanism of gastric cancer prevention by H. pylori eradication, mainly from an epigenetic perspective.

Non-Coding RNAs in Gastric Cancer: From Malignant Hallmarks to Clinical Applications

Gastric cancer (GC) is one of the most lethal malignancies worldwide. However, the molecular mechanisms underlying gastric carcinogenesis remain largely unknown. Over the past decades, advances in RNA-sequencing techniques have greatly facilitated the identification of various non-coding RNAs (ncRNAs) in cancer cells, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Accumulating evidence has revealed that ncRNAs are essential regulators in GC occurrence and development. However, ncRNAs represent an emerging field of cancer research, and their complex functionality remains to be clarified. Considering the lack of viable biomarkers and therapeutic targets in GC, further studies should focus on elucidating the intricate relationships between ncRNAs and GC, which can be translated into clinical practice. In this review, we summarize recent research progress on how ncRNAs modulate the malignant hallmarks of GC, especially in tumor immune escape, drug resistance, and stemness. We also discuss the promising applications of ncRNAs as diagnostic biomarkers and therapeutic targets in GC, aiming to validate their practical value for clinical treatment.

An integrated analysis of DNA promoter methylation, microRNA regulation, and gene expression in gastric adenocarcinoma

Background

Gastric adenocarcinoma (GAC), a common type of gastric cancer, poses a significant public health threat worldwide. This study aimed to determine the transcriptional regulatory mechanisms of GAC.

Methods

HTSeq-FPKM raw data were obtained from The Cancer Genome Atlas Stomach Adenocarcinoma data collection. Subsequently, the limma package in R was used to identify differentially expressed genes (DEGs). Differentially methylated genes (DMGs), DEGs, and differentially expressed microRNAs (miRNAs) in normal, and tumor tissues of the same patients were screened and compared using R software tools. A functional enrichment analysis was performed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) for various DEGs, DMGs, promoter methylation, and miRNAs. DEG-specific methylation and transcription factors were analyzed using ENCODE ChIP-seq.

Results

DEGs were centrally modified by the histone trimethylation of lysine 27 on histone H3 (H3K27me3). Upstream transcription factors of DEGs were enriched in different ChIP-seq clusters, such as Forkhead Box M1, E2F Transcription Factor 4, and suppressor of zest 12. Integrated regulatory networks of DEGs, promoter methylation, and miRNAs were constructed. Two miRNAs (hsa-mir-1 and hsa-mir-133a) and four DEGs (A disintegrin and metalloproteinase domain 12, transcription factor AP-2 alpha, solute carrier family 5 member 7, and cadherin 19) separately played important roles in the integrated regulatory network. Therefore, these DEGs, DMGs, promoter methylation, and miRNAs may play an important role in GAC pathogenesis.

Conclusions

In summary, the present study results provide insights into the oncogenesis and progression of GAC, thus accelerating the development of novel targeted GAC therapies.

Footprints of microRNAs in Cancer Biology

MicroRNAs (miRNAs) are short non-coding RNAs involved in post-transcriptional gene regulation. Over the past years, various studies have demonstrated the role of aberrant miRNA expression in the onset of cancer. The mechanisms by which miRNA exerts its cancer-promoting or inhibitory effects are apparent through the various cancer hallmarks, which include selective proliferative advantage, altered stress response, vascularization, invasion and metastasis, metabolic rewiring, the tumor microenvironment and immune modulation; therefore, this review aims to highlight the association between miRNAs and the various cancer hallmarks by dissecting the mechanisms of miRNA regulation in each hallmark separately. It is hoped that the information presented herein will provide further insights regarding the role of cancer and serve as a guideline to evaluate the potential of microRNAs to be utilized as biomarkers and therapeutic targets on a larger scale in cancer research.

Roquin2 suppresses breast cancer progression by inhibiting tumor angiogenesis via selectively destabilizing proangiogenic factors mRNA

Tumor angiogenesis is an essential step in tumor growth and metastasis. The initiation of tumor angiogenesis is dictated by a shift in the balance between proangiogenic and antiangiogenic gene expression programs. Roquin2 is a zinc-finger RNA-binding protein with important roles in mediating the expression of inflammatory genes, such as TNF, IL6 and PTGS2, which are also important angiogenic factors. In this study, we demonstrate that Roquin2 functions as a potent tumor angiogenesis regulator that inhibits breast tumor-induced angiogenesis by selectively destabilizing mRNA of proangiogenic gene transcripts, including endoglin (ENG), endothelin-1 (EDN1), vascular endothelial growth factor B (VEGFB) and platelet derived growth factor C (PDGFC). Roquin2 recognizes and binds the stem-loop structure in the 3'untranslated region (3'UTR) of these mRNAs via its ROQ domain to destabilize mRNA. Moreover, we found that Roquin2 expression was reduced in breast cancer cells and tissues, and associated with poor prognosis in breast cancer patients. Overexpression of Roquin2 inhibited breast tumor-induced angiogenesis in vitro and in vivo, whereas silencing Roquin2 enhanced tumor angiogenesis. In vivo induction of Roquin2 by adenovirus significantly suppressed breast tumor growth, metastasis and angiogenesis. Taken together, our results identify that Roquin2 is a novel breast cancer suppressor that inhibits tumor angiogenesis by selectively downregulating the expression of proangiogenic genes.

MicroRNA-1: Diverse role of a small player in multiple cancers

The process of cancer initiation and development is a dynamic and complex mechanism involving multiple genetic and non-genetic variations. With the development of high throughput techniques like next-generation sequencing, the field of cancer biology extended beyond the protein-coding genes. It brought the functional role of noncoding RNAs into cancer-associated pathways. MicroRNAs (miRNAs) are one such class of noncoding RNAs regulating different cancer development aspects, including progression and metastasis. MicroRNA-1 (miR-1) is a highly conserved miRNA with a functional role in developing skeletal muscle precursor cells and cardiomyocytes and acts as a consistent tumor suppressor gene. In humans, two discrete genes, MIR-1-1 located on 20q13.333 and MIR-1-2 located on 18q11.2 loci encode for a single mature miR-1. Downregulation of miR-1 has been demonstrated in multiple cancers, including lung, breast, liver, prostate, colorectal, pancreatic, medulloblastoma, and gastric cancer. A vast number of studies have shown that miR-1 affects the hallmarks of cancer like proliferation, invasion and metastasis, apoptosis, angiogenesis, chemosensitization, and immune modulation. The potential therapeutic applications of miR-1 in multiple cancer pathways provide a novel platform for developing anticancer therapies. This review focuses on the different antitumorigenic and therapeutic aspects of miR-1, including how it regulates tumor development and associated immunomodulatory functions.

Angiogenesis-related non-coding RNAs and gastrointestinal cancer

Gastrointestinal (GI) cancers are among the main reasons for cancer death globally. The deadliest types of GI cancer include colon, stomach, and liver cancers. Multiple lines of evidence have shown that angiogenesis has a key role in the growth and metastasis of all GI tumors. Abnormal angiogenesis also has a critical role in many non-malignant diseases. Therefore, angiogenesis is considered to be an important target for improved cancer treatment. Despite much research, the mechanisms governing angiogenesis are not completely understood. Recently, it has been shown that angiogenesis-related non-coding RNAs (ncRNAs) could affect the development of angiogenesis in cancer cells and tumors. The broad family of ncRNAs, which include long non-coding RNAs, microRNAs, and circular RNAs, are related to the development, promotion, and metastasis of GI cancers, especially in angiogenesis. This review discusses the role of ncRNAs in mediating angiogenesis in various types of GI cancers and looks forward to the introduction of mimetics and antagonists as possible therapeutic agents.

Syndecan-1 Promotes Angiogenesis in Triple-Negative Breast Cancer through the Prognostically Relevant Tissue Factor Pathway and Additional Angiogenic Routes

Simple Summary

Triple-negative breast cancer is an aggressive subtype of breast cancer characterized by tumor angiogenesis and poor patient survival. Here, we analyzed the function of the cell surface molecule Syndecan-1 in tumor angiogenesis in a 3D cell culture system. As a novel finding, we demonstrate that downregulation of Syndecan-1 reduces angiogenesis by decreasing the amount of angiogenesis factors of the tissue factor pathway. Furthermore, we show that the components of this pathway are associated with the prognosis of breast cancer patients. Our study identifies Syndecan-1 and the tissue factor pathway as novel potential therapeutic targets in the aggressive triple-negative subtype of breast cancer, for which no targeted therapies are currently available.

Abstract

Triple-negative breast cancer (TNBC) is characterized by increased angiogenesis, metastasis, and poor survival. Dysregulation of the cell surface heparan sulfate proteoglycan and signaling co-receptor Syndecan-1 is linked to poor prognosis. To study its role in angiogenesis, we silenced Syndecan-1 in TNBC cell lines using a 3D human umbilical vein endothelial cell (HUVEC) co-culture system. Syndecan-1 siRNA depletion in SUM-149, MDA-MB-468, and MDA-MB-231 cells decreased HUVEC tubule network formation. Angiogenesis array revealed reduced VEGF-A and tissue factor (TF) in the Syndecan-1-silenced secretome. qPCR independently confirmed altered expression of F3, F7, F2R/PAR1, F2RL1/PAR2, VEGF-A, EDN1, IGFBP1, and IGFBP2 in SUM-149, MDA-MB-231, and MDA-MB-468 cells. ELISA revealed reduced secreted endothelin-1 (SUM-149, MDA-MB-468) and TF (all cell lines) upon Syndecan-1 depletion, while TF pathway inhibitor treatment impaired angiogenesis. Survival analysis of 3951 patients demonstrated that high expression of F3 and F7 are associated with better relapse-free survival, whereas poor survival was observed in TNBC and p53 mutant basal breast cancer (F3) and in ER-negative and HER2-positive breast cancer (F2R, F2RL1). STRING protein network analysis revealed associations of Syndecan-1 with VEGF-A and IGFBP1, further associated with the TF and ET-1 pathways. Our study suggests that TNBC Syndecan-1 regulates angiogenesis via the TF and additional angiogenic pathways and marks its constituents as novel prognostic markers and therapeutic targets.

miR-1: A comprehensive review of its role in normal development and diverse disorders

MicroRNA-1 (miR-1) is a conserved miRNA with high expression in the muscle tissues. In humans, two discrete genes, MIRN1-1 and MIRN1-2 residing on a genomic region on 18q11.2 produce a single mature miRNA which has 21 nucleotides. miR-1 has a regulatory role on a number of genes including heat shock protein 60 (HSP60), Kruppel-like factor 4 (KLF4) and Heart And Neural Crest Derivatives Expressed 2 (HAND2). miR-1 has critical roles in the physiological processes in the smooth and skeletal muscles as well as other tissues, thus being involved in the pathogenesis of a wide range of disorders. Moreover, dysregulation of miR-1 has been noted in diverse types of cancers including gastric, colorectal, breast, prostate and lung cancer. In the current review, we provide the summary of the data regarding the role of this miRNA in the normal development and the pathogenic processes.

miR-100 inhibits cell proliferation in mantle cell lymphoma by targeting mTOR

Background

miR-100 is reported to be associated with cell proliferation and apoptosis. However, the function of miR-100 in mantle cell lymphoma (MCL) is unknown. The purpose of this study is to analyze the abnormal expression of miR-100 and mTOR in MCL together with their potential biological function and pathogenesis.

Method

Eighteen MCL tissue samples and 3 cell lines (Jeko-1, Mino, Granta-519) were investigated in this research study, while eighteen samples of proliferative lymphadenitis from patients and peripheral lymphocyte cells from healthy volunteers served as controls. The expression and alteration of miR-100 and mTOR mRNA were detected by RT-PCR. The expression and alteration of mTOR protein were explored by Western blot. LV-miR-100-up and LV-mTOR-RNAi were constructed and transfected by lentivirus transfection. Cell proliferation, cell apoptosis and the cell cycle were detected using CCK-8 and flow cytometry. Bioinformatics prediction software was used to predict the miR-100 target gene of mTOR. A double luciferase experiment was used to verify miR-100 targeting at the mTOR-3′-UTR. The interaction between miR-100 and mTOR was further studied using recovery experiments. GraphPad Prism 7 software (version 7.2) was used for statistical analysis, and a P value < 0.05 was considered statistically significant.

Results

We found that the expression of miR-100 mRNA in MCL tissues and cell lines was lower, while that of the mTOR protein was higher. There was a negative correlation between miR-100 and mTOR in both MCL tissues and cell lines. Promoting miR-100 and inhibiting mTOR could inhibit cell proliferation, induce cell apoptosis and block the cell cycle in the G1 phase. A double luciferase reporter assay showed that mTOR was one of the target genes of miR-100. The recovery experiment demonstrated that PV-mTOR-up partially set off the effect of LV-miR-100-up on decreasing mTOR expression, inhibiting proliferation, inducing apoptosis and blocking the cell cycle in G1 phase in both Jeko-1 and Mino cells.

Conclusions

Abnormal expression of miR-100 and mTOR was found in MCL, which included downregulation of miR-100 and upregulation of mTOR. The expression of mTOR is negatively correlated with miR-100. It may play an important role in MCL pathogenesis. miR-100 up-regulation can inhibit cell proliferation, promote cell apoptosis, and inhibit cell cycle in G1 phase by targeting the mTOR gene. miR-100 may potentially be an anti-mantle cell lymphoma gene.

Circular RNA circ-PVT1 contributes to paclitaxel resistance of gastric cancer cells through the regulation of ZEB1 expression by sponging miR-124-3p

Gastric cancer (GC) is the fifth most commonly diagnosed malignancy. Paclitaxel (PTX) is an effective first-line chemotherapy drug in GC treatment, but the resistance of PTX attenuates the therapeutic effect. Circular RNA circ-PVT1 can exert the oncogenic effect in GC. But the function of circ-PVT1 involved in PTX resistance of GC is still unknown. In the present study, the expression levels of circ-PVT1, miR-124-3p and ZEB1 in PTX-resistant GC tissues and cells were detected by quantitative real-time polymerase chain reaction (RT-qPCR). PTX resistance in PTX-resistant cells was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The protein levels of Zinc finger E-box binding homeobox 1 (ZEB1), P-glycoprotein (P-gp) and glutathione S-transferase (GST-π) were detected by Western blot assay. Cell apoptosis and invasion were measured in PTX-resistant cells by flow cytometry and transwell invasion assays, severally. The interaction between miR-124-3p and circ-PVT1 or ZEB1 was predicted by starBase software, and then verified by the dual-luciferase reporter assay. The role of circ-PVT1 in PTX resistance of GC in vivo was measured by xenograft tumor model. Our results showed that circ-PVT1 expression was up-regulated in PTX-resistant GC tissues and cells. Circ-PVT1 down-regulation enhanced PTX sensitivity in PTX-resistant GC cells by negatively regulating miR-124-3p. ZEB1 served as a direct target of miR-124-3p. Circ-PVT1 enhanced ZEB1 expression by sponging miR-124-3p. Circ-PVT1 knockdown increased PTX sensitivity of GC in vivo. Taken together, our studies disclosed that circ-PVT1 facilitated PTX resistance by up-regulating ZEB1 mediated via miR-124-3p, suggesting an underlying therapeutic strategy for GC.

Current perspectives on the dysregulated microRNAs in gastric cancer

Since gastric cancer (GC) is diagnosed at advanced stages, the survival rate is low in affected people. In this regard, investigating the mechanisms underlying GC development, are so critical. MiRNAs, which are small non coding RNAs, as a post transcriptional repressor, regulate expression of target genes by stimulating breakage or transcription suppression of their targets therefore aberrant expression of miRNAs leading to GC carcinogenesis. In the last decades, there have been various studies approving the pivotal role of miRNAs in various phases of GC development including cancer initiation, proliferation, migration, invasion, metastasis, angiogenesis, apoptosis, and drug resistance. Therefore, the present review aimed at summarizing the dysregulated miRNAs which contribute to various cellular and developmental mechanisms such as, proliferation, apoptosis, invasion, migration, and angiogenesis. Moreover, it provides an overview on novel miRNAs involved in drug resistance and circular miRNAs as cancer biomarkers. Thereafter, it is hoped that the present study will shed more light on diagnostic and prognostic biomarkers of GC, and potential GC treatments based on miRNAs.

Non-coding RNAs in gastric cancer

Non-coding RNAs (ncRNAs) are functional RNA molecules that play crucial regulatory roles in many fundamental biological processes. The dysregulation of ncRNAs is significantly associated with the progression of human cancers, including gastric cancer. In this review, we have summarized the oncogenic or tumor-suppressive roles and the regulatory mechanisms of lncRNAs, miRNAs, circRNAs and piRNAs, and have discussed their potential as biomarkers or therapeutic targets in gastric cancer.

MicroRNAs in gastric cancer: Biomarkers and therapeutic targets

MicroRNAs (miRNAs) are a group of non-coding RNAs that have critical roles in regulation of expression of genes. They can inhibit or decrease expression of target genes mostly via interaction with 3' untranslated region of their targets. Their crucial roles in the regulation of expression of tumor suppressor genes and oncogenes have potentiated them as contributors in tumorigenesis. Moreover, their stability in body fluids has enhanced their potential as cancer biomarkers. In the present review article, we describe the role of miRNAs in the pathogenesis of gastric cancer and advances in application of miRNAs as biomarkers and therapeutic targets in this kind of malignancy.

Cell Growth Stimulation, Cell Cycle Alternation, and Anti-Apoptosis Effects of Bovine Bone Collagen Hydrolysates Derived Peptides on MC3T3-E1 Cells Ex Vivo

Bovine bone collagen hydrolysates promote bone formation through regulating bone growth. However, the peptide sequences within these isolates have not been characterized. In this study, twenty-nine peptides from bovine bone collagen hydrolysates were purified and identified using nano-HPLC-MS-MS and Peak Studio analysis. HHGDQGAPGAVGPAGPRGPAGPSGPAGKDGR (Deamidation) and GPAGANGDRGEAGPAGPAGPAGPR (Deamidation) enhanced cell viability, inhibited apoptosis, and significantly altered the cell cycle of MC3T3-E1 osteoblast cells. These peptides were selected to perform molecular docking analysis to examine the mechanism underlying these bioactivities. Molecular docking analysis showed that these two peptides formed hydrophobic interactions and hydrogen bonds with epidermal growth factor receptor (EGFR) to activate the EGFR-signaling pathway, which may explain their bioactivity. These findings indicate that these and other similar peptides might be candidates for the treatment of osteoporosis.

Circular RNA circVAPA knockdown suppresses colorectal cancer cell growth process by regulating miR-125a/CREB5 axis

Background

Colorectal cancer (CRC) is a malignant tumor, and the overall prognosis of patients with advanced CRC is still unsatisfactory. Circular RNAs (circRNAs) vesicle-associated membrane protein-associated protein A (circVAPA) could act as an underlying biomarker in CRC. This study aimed to explore the mechanism of circVAPA in the regulation of CRC growth.

Methods

CircVAPA level was measured in CRC tumor tissues. The expression levels of circVAPA, VAPA mRNA, microRNA-125a (miR-125a), and cAMP response element binding 5 (CREB5) in CRC cells were detected by RT-qPCR. Cell cycle progression, migration and invasion, extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were measured by flow cytometry, transwell assays and Seahorse XF96 Glycolysis Analyzer, severally. The levels of glucose uptake, lactate and ATP production were examined by Glucose Uptake Colorimetric Assay kit, Lactate Assay kit and ATP Colorimetric Assay kit, respectively. The interaction between miR-125a and circVAPA or CREB5 was predicted by Starbase or DIANA TOOL, and verified by the dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays.

Results

CircVAPA level was up-regulated in CRC tumor tissues. Expression levels of circVAPA and CREB5 were increased, and miR-125a was decreased in CRC cells. CircVAPA knockdown repressed CRC cells cycle progression, migration, invasion and glycolysis. CircVAPA acted as a miR-125a sponge to regulate CREB5 expression. Rescue assay confirmed that miR-125a deletion or CREB5 overexpression weakened the inhibitory effect of circVAPA knockdown on CRC growth.

Conclusion

Our studies disclosed that circVAPA knockdown suppressed CRC cells cycle progression, migration, invasion and glycolysis partly by modulating miR-125a/CREB5 axis, suggesting a potential therapeutic strategy for CRC treatment.

MicroRNA Targeting Nicotinamide Adenine Dinucleotide Phosphate Oxidases in Cancer

Significance: Reactive oxygen species (ROS) production occurs primarily in the mitochondria as a by-product of cellular metabolism. ROS are also produced by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases in response to growth factors and cytokines by normal physiological signaling pathways. NADPH oxidase, a member of NADPH oxidase (NOX) family, utilizes molecular oxygen (O₂) to generate ROS such as hydrogen peroxide and superoxide. Imbalance between ROS production and its elimination is known to be the major cause of various human diseases. NOX family proteins are exclusively involved in ROS production, which makes them attractive target(s) for the treatment of ROS-mediated diseases including cancer. Recent Advances: Molecules such as Keap1/nuclear factor erythroid 2-related factor 2 (Nrf2), N-methyl-d-aspartic acid (NMDA) receptors, nuclear factor-kappaB, KRAS, kallistatin, gene associated with retinoic-interferon-induced mortality-19, and deregulated metabolic pathways are involved in ROS production in association with NADPH oxidase. Critical Issues: Therapeutic strategies targeting NADPH oxidases in ROS-driven cancers are not very effective due to its complex regulatory circuit. Tumor suppressor microRNAs (miRNAs) viz. miR-34a, miR-137, miR-99a, and miR-21a-3p targeting NADPH oxidases are predominantly downregulated in ROS-driven cancers. miRNAs also regulate other cellular machineries such as Keap1/Nrf2 pathway and NMDA receptors involved in ROS production and consequently drug resistance. Here, we discuss the structure, function, and metabolic role of NADPH oxidase, NOX family protein-protein interaction, their association with other pathways, and NADPH oxidase alteration by miRNAs. Moreover, we also discuss and summarize studies on NADPH oxidase associated with various malignancies and their therapeutic implications. Future Directions: Targeting NADPH oxidases through miRNAs appears to be a promising strategy for the treatment of ROS-driven cancer.

Epigenetic control of tumor angiogenesis

The term "epigenetic" is used to refer to heritable alterations in chromatin that are not due to changes in DNA sequence. Different growth factors and vascular genes mediate the angiogenic process, which is regulated by epigenetic states of genes. The aim of this article is to analyze the role of epigenetic mechanisms in the control and regulation of tumor angiogenetic processes. The reversibility of epigenetic events in contrast to genetic aberrations makes them potentially suitable for therapeutic intervention. In this context, DNA methyltransferase (DNMT) and HDAC inhibitors indirectly-via the tumor cells-exhibit angiostatic effects in vivo, and inhibition of miRNAs can contribute to the development of novel anti-angiogenesis therapies.

Analysis of circulating microRNAs aberrantly expressed in alcohol-induced osteonecrosis of femoral head

Serum miRNAs are potential biomarkers for predicting the progress of bone diseases, but little is known about miRNAs in alcohol-induced osteonecrosis of femoral head (AIONFH). This study evaluated disease-prevention value of specific serum miRNA expression profiles in AIONFH. MiRNA PCR Panel was taken to explore specific miRNAs in serum of AIONFH cases. The top differentially miRNAs were further validated by RT-qPCR assay in serum and bone tissues of two independent cohorts. Their biofunction and target genes were predicted by bioinformatics databases. Target genes related with angiogenesis and osteogenesis were quantified by RT-qPCR in necrotic bone tissue. Our findings demonstrated that multiple miRNAs were evaluated to be differentially expressed with high dignostic values. MiR-127-3p, miR-628-3p, and miR-1 were downregulated, whereas miR-885-5p, miR-483-3p, and miR-483-5p were upregulated in serum and bone samples from the AIONFH patients compared to those from the normal control individuals (p < 0.01). The predicted target genes of the indicated miRNAs quantified by qRT-PCR, including IGF2, PDGFA, RUNX2, PTEN, and VEGF, were presumed to be altered in necrotic bone tissue of AIONFH patients. The presence of five altered miRNAs in AIONFH patients may serve as non-invasive biomarkers and potential therapeutic targets for the early diagnosis of AIONFH.

Function of fibroblast growth factor 2 in gastric cancer occurrence and prognosis

The present study aimed to explore the role of fibroblast growth factor 2 (FGF2) in the development and prognosis of gastric cancer (GC). The relationship between FGF2 mRNA expression levels and the clinical characteristics of GC was investigated using microarray data from four GC cohorts involving 726 patients obtained from the Gene Expression Omnibus. The results of the present study indicated that FGF2 expression levels were an independent factor affecting the prognosis of GC. The primary functions of FGF2 were related to cell adhesion and angiogenesis, and patients with high levels of FGF2 expression had poorer TNM staging and prognosis; these differences were statistically significant. In terms of immune infiltration, a higher extent of M2 macrophage intrusion was observed in patients with higher levels of FGF2. However, the degree of infiltration by dendritic and CD4⁺ T cells was lower, and this difference was statistically significant. Multivariate Cox proportional hazards model analysis revealed that age, TNM staging and FGF2 expression levels were independent prognostic factors for GC. In summary, FGF2 expression was demonstrated to be an independent prognostic factor in GC, and higher levels of FGF2 may promote the progression of this malignancy.

MiR-4766-5p Inhibits The Development And Progression Of Gastric Cancer By Targeting NKAP

Purpose

It is widely known that some specific microRNAs can regulate the expressions of genes in gastric cancer cells at the post-transcriptional level. Previous studies have identified that miRNA-4766-5p was involved in tumor cell proliferation and can be an independent prognostic indicator for malignant pleural mesothelioma. However, the mechanism underlying gastric cancer via the miRNA-4766-5p pathway remains to be blank.

Methods

We investigated the expression of miR-4766-5p in gastric cancer tissues and cells through qRT-PCR. We used RNAi to change the expressions of miR-4766-5p in gastric cancer cell lines, AGS and MKN45. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to detect the mRNA expression of miR-4766-5p. We identified cell proliferation by CCK8 and clone formation assays. We analyzed the cell apoptosis and cycle through flow cytometry. At last, we used a dual-luciferase reporter assay to illustrate the interaction between miR-4766-5p and NKAP and used Western blot to determine the protein expression of signaling pathways.

Results

We found that 1) miR-4766-5p was down-regulated in gastric cancer tissues and cells lines; 2) miR-4766-5p inhibited cell proliferation of gastric cancer cell lines significantly; 3) miR-4766-5p significantly inhibited cell migration and invasion of gastric cancer cells; 4) miR-4766-5p induced gastric cancer cell apoptosis. 5) NKAP was a direct target gene of miR-4766-5p; and 6) miR-4766-5p induced inactivation of AKT/mTOR pathway.

Conclusion

The above results indicate that miR-4766-5p suppressed the proliferation and metastasis of gastric cancer cells through targeting NKAP. Our findings could probably contribute to the diagnostics and prognostics of gastric cancer through new methodologies.

MicroRNA-188-5p promotes apoptosis and inhibits cell proliferation of breast cancer cells via the MAPK signaling pathway by targeting Rap2c

Breast cancer is a common malignancy that is highly lethal with poor survival rates and immature therapeutics that urgently needs more effective and efficient therapies. MicroRNAs are intrinsically involved in different cancer remedies, but their mechanism in breast cancer has not been elucidated for prospective treatment. The function and mechanism of microRNA-188-5p (miR-188) have not been thoroughly investigated in breast cancer. In our study, we found that the expression of miR-188 in breast cancer tissues was obviously reduced. Our findings also revealed the abnormal overexpression of miR-188 in 4T1 and MCF-7 cells significantly suppressed cell proliferation and migration and also enhanced apoptosis. miR-188 induced cell cycle arrest in the G1 phase. To illuminate the molecular mechanism of miR-188, Rap2c was screened as a single target gene by bioinformatics database analysis and was further confirmed by dual-luciferase assay. Moreover, Rap2c was found to be a vital molecular switch for the mitogen-activated protein kinase signaling pathway in tumor progression by decreasing apoptosis and promoting proliferation and migration. In conclusion, our results revealed that miR-188 is a cancer progression suppressor and a promising future target for breast cancer therapy.

miR‑1 reverses multidrug resistance in gastric cancer cells via downregulation of sorcin through promoting the accumulation of intracellular drugs and apoptosis of cells

Gastric cancer (GC) is one of the most common cancers worldwide and results in the second greatest rate of cancer-associated mortality globally. Multidrug resistance (MDR) often develops during the chemotherapy, resulting in the failure of treatment. To investigate the molecular mechanism of MDR, the roles of microRNA (miR)-1 were studied in GC. Reverse transcription-quantitative polymerase chain reaction and western blotting were used to investigate the expression levels of miR-1 and sorcin in SGC7901/ADM and SGC7901/VCR cell lines. The effect of miR-1 on the half maximal inhibitory concentration (IC₅₀), cell apoptosis rates and drug accumulation was uncovered by MTT assay and flow cytometric analysis. Furthermore, dual-luciferase assay and western blotting were used to determine the target of miR-1 in GC. It was demonstrated that miR-1 was highly downregulated in MDR GC cell lines, including SGC7901/ADM and SGC7901/VCR. Overexpression of miR-1 in MDR GC cells decreased IC₅₀, but increased the cell apoptosis rates and promoted the drug accumulation in cancer cells. Dual-luciferase activity assay indicated that sorcin was the target of miR-1 in GC. In addition, overexpression of sorcin could partially reverse the effect of miR-1 in MDR GC cells. The role of miR-1 in MDR GC cells makes it a potential therapeutic target for a successful clinical outcome.

Clinical significance of miRNA‑1 and its potential target gene network in lung squamous cell carcinoma

Previous studies demonstrated that miRNA-1 (miR-1) is downregulated in certain human cancer and serves a crucial role in the progression of cancer. However, there are only a few previous studies examining the association between miR-1 and lung squamous cell carcinoma (LUSC) and the regulatory mechanism of miR-1 in LUSC remains unclear. Therefore, the present study investigated the clinical significance and determined the potential molecular mechanism of miR-1 in LUSC. The expression of miR-1 and its clinical significance in LUSC was examined by conducting a meta-analysis of 12 studies using Stata 14, MetaDiSc1.4 and SPSS version 23. In addition, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using the potential target genes of miR-1 gathered from Gene Expression Omnibus and ArrayExpress. Meta-analysis demonstrated that miR-1 was significantly downregulated in LUSC [standardized mean difference: −1.44; 95% confidence interval (CI): −2.08, −0.81], and the area under the curve was 0.9096 (Q*=0.8416) with sensitivity of 0.71 (95% CI: 0.66, 0.76) and specificity of 0.88 (95% CI: 0.86, 0.90). The pooled positive likelihood ratio and negative likelihood ratio were 4.93 (95% CI: 2.54, 9.55) and 0.24 (95% CI: 0.10, 0.54), respectively. Bioinformatics analysis demonstrated that miR-1 may be involved in the progression of LUSC via the ‘cell cycle’, ‘p53 signaling pathway’, ‘Fanconi anemia pathway’, ‘homologous recombination’, ‘glycine, serine and threonine metabolism’ and ‘oocyte meiosis’. In summary, miR-1 was significantly downregulated in LUSC, suggesting a novel and promising non-invasive biomarker for diagnosing LUSC, and miR-1 was involved in LUSC progression via a number of significant pathways.

An overview of the multifaceted roles of miRNAs in gastric cancer: Spotlight on novel biomarkers and therapeutic targets

MicroRNAs (miRNAs) are a group of small non-coding RNAs that have displayed strong association with gastric cancer (GC). Through the repression of target mRNAs, miRNAs regulate many biological pathways that are involved in cell proliferation, apoptosis, migration, invasion, metastasis as well as drug resistance. The detection of miRNAs in tissues and in body fluids emerges as a promising method in the diagnosis and prognosis of GC, due to their unique expression pattern in correlation with GC. Notably, miRNAs are also identified as potential therapeutic targets for GC therapy. The present review is thus to highlight the multifaceted roles of miRNAs in GC and in GC therapies, which would give indications for future research.

Potential tumor‑suppressive role of microRNA‑99a‑3p in sunitinib‑resistant renal cell carcinoma cells through the regulation of RRM2

Sunitinib is the most common primary molecular‑targeted agent for metastatic clear cell renal cell carcinoma (ccRCC); however, intrinsic or acquired sunitinib resistance has become a significant problem in medical practice. The present study focused on microRNA (miR)‑99a‑3p, which was significantly downregulated in clinical sunitinib‑resistant ccRCC tissues in previous screening analyses, and investigated the molecular network associated with it. The expression levels of miR‑99a‑3p and its candidate target genes were evaluated in RCC cells, including previously established sunitinib‑resistant 786‑o (SU‑R‑786‑o) cells, and clinical ccRCC tissues, using reverse transcription‑quantitative polymerase chain reaction. Gain‑of‑function studies demonstrated that miR‑99a‑3p significantly suppressed cell proliferation and colony formation in RCC cells, including the SU‑R‑786‑o cells, by inducing apoptosis. Based on in silico analyses and RNA sequencing data, followed by luciferase reporter assays, ribonucleotide reductase regulatory subunit‑M2 (RRM2) was identified as a direct target of miR‑99a‑3p in the SU‑R‑786‑o cells. Loss‑of‑function studies using small interfering RNA against RRM2 revealed that cell proliferation and colony growth were significantly inhibited via induction of apoptosis, particularly in the SU‑R‑786‑o cells. Furthermore, the RRM2 inhibitor Didox (3,4‑dihydroxybenzohydroxamic acid) exhibited anticancer effects in the SU‑R‑786‑o cells and other RCC cells. To the best of our knowledge, this is the first report demonstrating that miR‑99a‑3p directly regulates RRM2. Identifying novel genes targeted by tumor‑suppressive miR‑99a‑3p in sunitinib‑resistant RCC cells may improve our understanding of intrinsic or acquired resistance and facilitate the development of novel therapeutic strategies.

Overexpression of MicroRNA-1 in Prostate Cancer Cells Modulates the Blood Vessel System of an In Vivo Hen's Egg Test-Chorioallantoic Membrane Model

BACKGROUND/AIM

In prostate cancer (PC), the formation of new blood vessels is stimulated by hypoxic conditions, androgens, and a number of molecular factors including microRNAs. MicroRNA-1 (miR-1) has been characterized in some tumor entities as anti-angiogenic, but this has not yet been investigated in PC.

MATERIALS AND METHODS

PC cells stably overexpressing miR-1 (LNCaP-miR-1) were incubated on an in vivo hen's egg test-chorioallantoic membrane (HET-CAM) model and compared to maternal LNCaP cells. Cell growth, blood vessel organisation, and total blood vessel area were analysed.

RESULTS

Both matrigel-embedded LNCaP and LNCaP-miR-1 cells formed compact tumor-like cell aggregates on the CAM of the HET-CAM model. Although not quantifiable, bleeding of the CAM and remodelling of the blood vessel network in the CAM indicated an influence of miR-1 on the vascular system. The statistically significant decrease in the total surface area of blood vessels in the visible CAM section to 79.4% of control cells demonstrated the antiangiogenic properties of miR-1 for the first time.

CONCLUSION

MiR-1 had a tumor-suppressive and anti-angiogenic effect in an in vivo PC model. In the clinic, miR-1-mediated anti-angiogenesis would result in reduced tumor supply and increased hypoxic stress inside the tumor. Thus, miR-1 restoration by nucleic acid-based miR-1 mimetics would represent a promising option for future PC therapy.

Upregulation of microRNA 344a-3p is involved in curcumin induced apoptosis in RT4 schwannoma cells

Background

Schwannoma arising from peripheral nervous sheaths is a benign tumor.

Methods

To evaluate cell cytotoxicity, (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium reduction and terminal deoxynucleotidyltransferase UTP nick-end labeling (TUNEL) assays were used. A microRNA (miRNA) array was used to identify the miRNAs involved in curcumin-induced apoptosis. To examine miRNA expression, quantitative RT-PCR was used.

Results

In this study, curcumin exerted cellular cytotoxicity against RT4 schwannoma cells, with an increase in TUNEL-positive cells. Curcumin also activated the expression of apoptotic proteins, such as polyADP ribose polymerase, caspase-3, and caspase-9. The miRNA array revealed that seven miRNAs (miRNA 350, miRNA 17-2-3p, let 7e-3p, miRNA1224, miRNA 466b-1-3p, miRNA 18a-5p, and miRNA 322-5p) were downregulated following treatment with both 10 and 20 μM curcumin in RT4 cells, while four miRNAs (miRNA122-5p, miRNA 3473, miRNA182, and miRNA344a-3p) were upregulated. Interestingly, transfection with a miRNA 344a-3p mimic downregulated the mRNA expression of Bcl2 and upregulated that of Bax, Curcumin treatment in RT 4 cells also reduced the mRNA expression of Bcl2 and enhanced expression of Bax, Overexpression of miRNA344a-3p mimic combined with curcumin treatment activated the expression of apoptotic proteins, including procaspase-9 and cleaved caspase-3 while inhibition of miRNA 344a-3p using miR344a-3p inhibitor repressed cleaved caspase-3 and -9 in curcumin treated RT-4 cells compared to control.

Conclusions

Our findings demonstrate that curcumin induces apoptosis in schwannoma cells via miRNA 344a-3p. Thus, curcumin may serve as a potent therapeutic agent for the treatment of schwannoma.

MiR-1-5p is down-regulated in gallbladder carcinoma and suppresses cell proliferation, migration and invasion by targeting Notch2

BACKGROUND

Numerous studies have demonstrated that aberrant microRNAs (miRNAs) are involved in tumorigenesis and tumor progression. Nevertheless, the precise role of miR-1-5p in gallbladder carcinoma cell growth and metastasis remains not fully revealed.

MATERIAL AND METHODS

The levels of miR-1-5p were detected in gallbladder carcinoma tissues and cell lines using qRT-PCR method. A series of functional assays, including cell proliferation, colony formation, wound healing and Transwell invasion were conducted using miR-1-5p or miR-1-5p inhibitor transfected cells.

RESULTS

MiR-1-5p was remarkably down-regulated in gallbladder carcinoma tissues and cell lines compared to normal. In addition, over-expression of miR-1-5p markedly suppressed the growth, migration and invasion of gallbladder carcinoma cell. Conversely, down-expression of miR-1-5p facilitated gallbladder carcinoma cell proliferation and aggressiveness. Mechanistic investigations demonstrated that neurogenic locus notch homolog protein 2 (Notch2) was the directly target of miR-1-5p and Notch2 mediated the inhibitory effect of miR-1-5p in gallbladder carcinoma cell growth and aggressiveness.

CONCLUSION

Our findings demonstrated that miR-1-5p acted as a suppressive miRNA and played vital roles in the growth, migration and invasion of gallbladder carcinoma cell through targeting Notch2.

MicroRNAs as biological regulators in skin disorders

microRNAs are being investigated as promising therapeutic targets and biomarkers for different disease conditions. miRNAs serve as essential regulators of cell differentiation, proliferation and survival. The involvement of miRNAs in the functioning and regulation of the skin cells and skin diseases is a rapidly advancing area in dermatological research. miRNAs have been identified to play a key role in the pathogenesis, diagnosis, and treatment of the skin diseases. Skin is one of the largest organs of the body, primarily functioning as the first line of defence against external insults including bacteria, virus and other pathogens. Various miRNAs have been identified to demonstrate significant effects in various skin inflammatory conditions such as wounds, cancer, psoriasis, scleroderma, dermatomyositis. The current review explores the possible roles of the miRNAs in skin disorders and reports relating to the clinical trials involving skin diseases and miRNAs. The review has also compiled the information of the databases available, which correlates the miRNAs with different diseases and give details about targeting interactions of miRNA.

MicroRNA-140-5p suppresses cell proliferation and invasion in gastric cancer by targeting WNT1 in the WNT/β-catenin signaling pathway

MicroRNAs have been suggested as potential regulators in gastric cancer (GC) development through affecting the expression of their target genes. Previous studies have demonstrated that miR-140-5p is downregulated in GC. However, the underlying functional role of miR-140-5p in GC remains largely unknown. The present study revealed that miR-140-5p expression was significantly decreased in 60 GC tissues, compared with corresponding adjacent non-tumor tissues. A lower miR-140-5p expression was significantly associated with lymph node metastasis and an advanced Tumor-Node-Metastasis stage in patients with GC. Furthermore, patients with a lower miR-140-5p expression exhibited shorter disease-free survival and overall survival times. Gain- and loss-of-function assays revealed that increased miR-140-5p expression significantly inhibited GC cell proliferation and invasion ability, as well as the Wnt/β-catenin signaling pathway by decreasing WNT1 and β-catenin expression. However, decreasing miR-140-5p expression had the opposite effects. Bioinformatics methods and dual-luciferase reporter assays revealed that WNT1 was a direct target of miR-140-5p. miR-140-5p suppressed cell proliferation and invasion by regulating WNT1 expression. Therefore, the results of the present study demonstrated that miR-140-5p may serve as a potential prognostic marker and therapeutic target in patients with GC.

MicroRNA-214 promotes the proliferation, migration and invasion of gastric cancer MKN28 cells by suppressing the expression of Dact2

The present study examined the expression of Dapper, antagonist of β-catenin 2 (Dact2) and microRNA (miR)-214 in gastric cancer at tissue and cellular levels, and to understand their biological roles. A total of 42 gastric cancer patients were enrolled in the present study. Bioinformatics tool was used to predict the miR molecule that potentially regulates Dact2 expression. To measure the expression of miR-214 and Dact2, reverse transcription-quantitative polymerase chain reaction was employed. Mixed gastric adenocarcinoma type MKN28 cells were transfected with negative control (NC), miR-214 mimics or inhibitor. The CCK-8 assay was used to investigate the proliferation of mixed gastric adenocarcinoma type MKN28 cells. To study migration and invasion abilities of mixed gastric adenocarcinoma type MKN28 cells, the Transwell assay was performed. To determine the expression of Dact2 protein, western blotting was conducted and the rescue assay was utilized to study the biological roles of miR-214 and Dact2 in mixed gastric adenocarcinoma type MKN28 cells. To test whether Dact2 is a direct target of miR-214, the dual luciferase reporter assay was performed. Results indicated that the expression of miR-214 was elevated, but expression of Dact2 mRNA was decreased in gastric cancer tissues, which was closely correlated with the invasion, metastasis, occurrence and development of gastric cancer. Notably, miR-214 promoted the proliferation of mixed gastric adenocarcinoma type MKN28 cells in vitro, whereas but Dact2 inhibited the proliferation of these cells. Downregulation of miR-214 expression or upregulation of Dact2 expression inhibited the migration and invasion of mixed gastric adenocarcinoma type MKN28 cells. Furthermore, miR-214 regulated the expression of Dact2 protein and its downstream β-catenin protein in mixed gastric adenocarcinoma type MKN28 cells. Dact2 reversed the effect of miR-214 on the proliferation, migration and invasion of mixed gastric adenocarcinoma type MKN28 cells. In addition, miR-214 directly targeted the 3'-UTR seeding region of Dact2 mRNA to regulate its expression. The present study demonstrated that expression of miR-214 was upregulated in gastric cancer tissues, and positively correlated with lymphatic metastasis and clinical staging. In addition, expression of Dact2 was downregulated in gastric cancer tissues and negatively correlated with lymphatic metastasis and clinical staging. Notably, the present findings suggest that miR-214 promoted the proliferation, migration and invasion of mixed gastric adenocarcinoma type MKN28 cells by suppressing the expression of Dact2.

Genomic markers of resistance to targeted treatments in gastric cancer: potential new treatment strategies

Gastric cancer is a highly heterogeneous disease, displaying a complex genomic landscape and an unfavorable outcome with standard therapies. Based on distinctive genomic alterations, novel targeted agents have been developed with the aim of personalizing treatments and improving patient outcome. However, a subgroup of patients is primarily treatment-resistant, and even in the initially sensitive population, secondary resistance emerges, thus limiting therapeutic benefit. In this review, we summarize the clinical data about standard targeted agents in gastric cancer, specifically anti-HER2 treatments and antivascular therapies. We also illustrate the available evidence regarding molecular mechanisms of resistance to these agents and we discuss potential strategies for new targeted treatments that could overcome such resistance.

Integrative Analysis of Dysregulated lncRNA-Associated ceRNA Network Reveals Functional lncRNAs in Gastric Cancer

Mounting evidence suggests that long noncoding RNAs (lncRNAs) play important roles in the regulation of gene expression by acting as competing endogenous RNA (ceRNA). However, the regulatory mechanisms of lncRNA as ceRNA in gastric cancer (GC) are not fully understood. Here, we first constructed a dysregulated lncRNA-associated ceRNA network by integrating analysis of gene expression profiles of lncRNAs, microRNAs (miRNAs), and messenger RNAs (mRNAs). Then, we determined three lncRNAs (RP5-1120P11, DLEU2, and DDX11-AS1) as hub lncRNAs, in which associated ceRNA subnetworks were involved in cell cycle-related processes and cancer-related pathways. Furthermore, we confirmed that the two lncRNAs (DLEU2 and DDX11-AS1) were significantly upregulated in GC tissues, promote GC cell proliferation, and negatively regulate miRNA expression, respectively. The hub lncRNAs (DLEU2 and DDX11-AS1) could have oncogenic functions, and act as potential ceRNAs to sponge miRNA. Our findings not only provide novel insights on ceRNA regulation in GC, but can also provide opportunities for the functional characterization of lncRNAs in future studies.

MiR-129-5p functions as a tumor suppressor in gastric cancer progression through targeting ADAM9

MicroRNAs (miRNAs) are identified as key regulators in cancer initiation, progression and metastasis including gastric cancer (GC). The aim of the study is to explore clinical significance and potential mechanism of miR-129-5p in GC development. In the study, our results found that miR-129-5p expression was significantly downregulated in GC tissues, compared with adjacent normal tissues using qRT-PCR analyses. Furthermore, lower miR-129-5p expression closely associated with tumor size and lymph node invasion and poor prognosis of GC patients. Using CCK8 assay, cell colony formation, transwell invasion assay, we demonstrated that miR-129-5p overexpression reduced cell proliferation, cell colony formation and cell invasion capacity in MKN45 (higher miR-129-5p expression) and SGC-7901 (lower miR-129-5p expression). However, downregulation of miR-129-5p had reverse effects on cell proliferation and invasion. Targeting association analysis, dual luciferase assay, qRT-PCR and western blot analysis results verified that miR-129-5p could target the 3'UTR of ADAM9 mRNA and regulated its protein expression. Furthermore, we confirmed that miR-129-5p suppressed cell proliferation and invasion ability through regulating ADAM9. In vivo, upregulation of miR-129-5p also inhibited tumor growth. Therefore, these results indicated that miR-129-5p functioned as a tumor suppressor in GC and may be a potential target of GC treatment.

Spotlight on the transglutaminase 2 gene: a focus on genomic and transcriptional aspects

The type 2 isoenzyme is the most widely expressed transglutaminase in mammals displaying several intra- and extracellular activities depending on its location (protein modification, modulation of gene expression, membrane signalling and stabilization of cellular interactions with the extracellular matrix) in relation to cell death, survival and differentiation. In contrast with the appreciable knowledge about the regulation of the enzymatic activities, much less is known concerning its inducible expression, which is altered in inflammatory and neoplastic diseases. In this context, we first summarize the gene's basic features including single-nucleotide polymorphism characterization, epigenetic DNA methylation and identification of regulatory regions and of transcription factor-binding sites at the gene promoter, which could concur to direct gene expression. Further aspects related to alternative splicing events and to ncRNAs (microRNAs and lncRNAs) are involved in the modulation of its expression. Notably, this important gene displays transcriptional variants relevant for the protein's function with the occurrence of at least seven transcripts which support the synthesis of five isoforms with modified catalytic activities. The different expression of the TG2 (type 2 transglutaminase) variants might be useful for dictating the multiple biological features of the protein and their alterations in pathology, as well as from a therapeutic perspective.

Role of MicroRNA in Proliferation Phase of Wound Healing

Wound healing is a complex biological process that is generally composed of four phases: hemostasis, inflammation, proliferation, and remodeling. The proliferation phase is crucial for effective healing compared to other phases. Many critical events occur during this phase, i.e., migration of fibroblasts, re-epithelialization, angiogenesis and wound contraction. Chronic wounds are common and are considered a major public health problem. Therefore, there is the increasing need to discover new therapeutic strategies. MicroRNA (miRNA) research in the field of wound healing is in its early phase, but the knowledge of the recent discoveries is essential for developing effective therapies for the treatment of chronic wounds. In this review, we focused on recently discovered miRNAs which are involved in the proliferation phase of wound healing in the past few years and their role in wound healing.

MicroRNA-100 suppresses human gastric cancer cell proliferation by targeting CXCR7

microRNAs (miRs) are a class of small non-coding RNAs that have been demonstrated to have a crucial role in tumorigenesis of human cancers, including gastric cancer (GC). Previous results have established that miR-100 participated in the development of GC; however, the underlying mechanism remains largely unknown. The preesent study utilized reverse transcription-quantitative polymerase chain reaction to analyze the expression of miR-100 in GC tissues and adjacent normal tissues. The present results indicated that the expression of miR-100 was downregulated in GC tissues when compared to the adjacent normal tissues. Furthermore, low miR-100 expression was observed to be associated with lymph node metastasis, tumor diameter and tumor stage. In addition, Kaplan-Meier analysis revealed that patients with low miR-100 expression tended to have a shorter overall survival. The miR-100 was further identified as an independent prognostic factor for overall survival. Notably, the levels of chemokine (CXC motif) receptor 7 (CXCR7) were inversely correlated with miR-100 in GC cell lines. Furthermore, miR-100 overexpression or CXCR7 depletion decreased in vitro GC cell proliferation. Bioinformatics analysis indicated that miR-100 may bind to the 3'-untranslated region of CXCR7 to prevent the initiation of protein translation. Thus, miR-100 may function as a tumor suppressor in GC, partly by regulating the expression of CXCR7, and the regulation of miR-100 expression may be a potential strategy for the treatment of GC patients.