The molecular mechanism of microRNA-145 to suppress invasion-metastasis cascade in gastric cancer

Stemness genes and miR-1247-3p expression associate with clinicopathological parameters and prognosis in lung adenocarcinoma

Lung cancer makes up one-fourth of all cancer-related mortality with the highest mortality rate among all cancers. Despite recent scientific advancements in cancer therapeutics, the 5-year survival rate of lung adenocarcinoma (LUAD) cancer patients remains below 15 percent. It has been suggested that the high mortality rate of LUAD is linked to the acquisition of progenitor-like cells with stem-like characteristics that assist the whole tumor in regulating immune cell infiltration. To examine this hypothesis further, this study mined several databases to explore the presence of stemness-related genes and miRNAs in LUAD cancers. We examine their association with immune and accessory cell infiltration rates and patient survival. We found 3 stem cell-related genes, ORC1L, KIF20A, and DLGAP5, present in LUAD that also correlate with changes in immune infiltration rates and reduced patient survival rates. Additionally, the modulation in myeloid-derived suppressor cell (MDSC) infiltration and miRNA hsa-mir-1247-3p mediated targeting of tumor suppressor SLC24A4 and oncogenes RAB3B and HJURP appears to primarily regulate LUAD patient survival. Given these findings, hsa-mir-1247-3p and/or its associated gene targets may offer a promising avenue to enhance patient survivability.

Matrix Metalloproteinase 9/microRNA-145 Ratio: Bridging Genomic and Immunological Variabilities in Thyroid Cancer

Matrix metalloproteinase 9 (MMP9) and microRNA-145 (miR-145) have emerged as essential biomarkers in thyroid cancer progression and metastasis. However, their combined evaluation and clinical utility as a unified prognostic marker across diverse thyroid cancer subgroups remain unexplored. We investigated the diagnostic and prognostic value of the MMP9/miR-145 ratio in thyroid cancer, hypothesizing it may overcome inter-patient heterogeneity and serve as a versatile biomarker regardless of genetic mutations or autoimmune status. MMP9 and miR-145 expressions were analyzed in 175 paired papillary thyroid cancer (PTC) and normal tissues. Plasma levels were assessed perioperatively and longitudinally over 12-18 months in 86 matched PTC patients. The associations with clinicopathological parameters and patient outcomes were evaluated. MMP9 was upregulated, and miR-145 downregulated in cancer tissues, with a median MMP9/miR-145 ratio 17.6-fold higher versus controls. The tissue ratio accurately diagnosed thyroid malignancy regardless of BRAF mutation or Hashimoto's thyroiditis status, overcoming genetic and autoimmune heterogeneity. A high preoperative circulating ratio predicted aggressive disease features, including lymph node metastasis, extrathyroidal extension, progression/relapse, and recurrence. Although the preoperative plasma ratio was elevated in patients with unfavorable outcomes, it had limited utility for post-surgical monitoring. In conclusion, the MMP9/miR-145 ratio is a promising biomarker in PTC that bridges genetic and immunological variabilities, enhancing preoperative diagnosis and prognostication across diverse patient subgroups. It accurately stratifies heterogenous cases by aggressiveness. The longitudinal trends indicate decreasing applicability for post-thyroidectomy surveillance. Further large-scale validation and protocol standardization can facilitate clinical translation of the MMP9/miR-145 ratio to guide personalized thyroid cancer management.

Emerging roles of miR-145 in gastrointestinal cancers: A new paradigm

Gastrointestinal (GI) carcinomas are a group of cancers affecting the GI tract and digestive organs, such as the gastric, liver, bile ducts, pancreas, small intestine, esophagus, colon, and rectum. MicroRNAs (miRNAs) are small functional non-coding RNAs (ncRNAs) which are involved in regulating the expression of multiple target genes; mainly at the post-transcriptional level, via complementary binding to their 3'-untranslated region (3'-UTR). Increasing evidence has shown that miRNAs have critical roles in modulating of various physiological and pathological cellular processes and regulating the occurrence and development of human malignancies. Among them, miR-145 is recognized for its anti-oncogenic properties in various cancers, including GI cancers. MiR-145 has been implicated in diverse biological processes of cancers through the regulation of target genes or signaling, including, proliferation, differentiation, tumorigenesis, angiogenesis, apoptosis, metastasis, and therapy resistance. In this review, we have summarized the role of miR-145 in selected GI cancers and also its downstream molecules and cellular processes targets, which could lead to a better understanding of the miR-145 in these cancers. In conclusion, we reveal the potential diagnostic, prognostic, and therapeutic value of miR-145 in GI cancer, and hope to provide new ideas for its application as a biomarker as well as a therapeutic target for the treatment of these cancer.

Simultaneous suppression of miR-21 and restoration of miR-145 in gastric cancer cells; a promising strategy for inhibition of cell proliferation and migration

Introduction

Gastric cancer (GC) is the third leading cause of cancer-related death worldwide. microRNAs are a group of regulatory non-coding RNAs that are involved in GC progression. miR-145 as a tumor suppressor and miR-21 as an oncomiR were shown to be dysregulated in many cancers including GC. This research aimed to enhance the expression of miR-145 while reducing the expression of miR-21 and examine their impact on the proliferation, apoptosis, and migration of GC cells.

Methods

KATO III cells with high expression levels of miR-21-5p and low expression of miR-145-5p were selected. These cells were then transfected with either miR-145-5p mimics or anti-miR-21-5p, alone or in combination. Afterward, the cell survival rate was determined using the MTT assay, while apoptosis induction was investigated through V-FITC/PI and DAPI staining. Additionally, cell migration was examined using the wound healing assay, and cell cycle progression was analyzed through flow cytometry. Furthermore, gene expression levels were quantified utilizing the qRT-PCR technique.

Results

The study's findings indicated that the co-replacement of miR-145-5p and anti-miR-21-5p led to a decrease in cell viability and the induction of apoptosis in GC cells. This was achieved via modulating the expression of Bax and Bcl-2, major cell survival regulators. Additionally, the combination therapy significantly increased sub-G1 cell cycle arrest and reduced cell migration by downregulating MMP-9 expression as an epithelial-mesenchymal transition marker. This study provides evidence for the therapeutic possibility of the combination of miR-145-5p and anti-miR-21-5p and also suggests that they could inhibit cell proliferation by modulating the PTEN/AKT1 signaling pathway.

Conclusion

Our research revealed that utilizing miR-145-5p and anti-miR-21-5p together could be a promising therapeutic approach for treating GC.

Circulating and extracellular vesicle-derived microRNAs as biomarkers in bone-related diseases

MicroRNAs (miRNA) are small non-coding RNA molecules that regulate posttranscriptional gene expression by repressing messengerRNA-targets. MiRNAs are abundant in many cell types and are secreted into extracellular fluids, protected from degradation by packaging in extracellular vesicles. These circulating miRNAs are easily accessible, disease-specific and sensitive to small changes, which makes them ideal biomarkers for diagnostic, prognostic, predictive or monitoring purposes. Specific miRNA signatures can be reflective of disease status and development or indicators of poor treatment response. This is especially important in malignant diseases, as the ease of accessibility of circulating miRNAs circumvents the need for invasive tissue biopsy. In osteogenesis, miRNAs can act either osteo-enhancing or osteo-repressing by targeting key transcription factors and signaling pathways. This review highlights the role of circulating and extracellular vesicle-derived miRNAs as biomarkers in bone-related diseases, with a specific focus on osteoporosis and osteosarcoma. To this end, a comprehensive literature search has been performed. The first part of the review discusses the history and biology of miRNAs, followed by a description of different types of biomarkers and an update of the current knowledge of miRNAs as biomarkers in bone related diseases. Finally, limitations of miRNAs biomarker research and future perspectives will be presented.

Role of a Mixture of Polyphenol Compounds Released after Blueberry Fermentation in Chemoprevention of Mammary Carcinoma: In Vivo Involvement of miR-145

Epigenetic mechanisms such as microRNA (miRNA) deregulation seem to exert a central role in breast cancer initiation and progression. Therefore, targeting epigenetics deregulation may be an effective strategy for preventing and halting carcinogenesis. Studies have revealed the significant role of naturally occurring polyphenolic compounds derived from fermented blueberry fruits in cancer chemoprevention by modulation of cancer stem cell development through the epigenetic mechanism and regulation of cellular signaling pathways. In this study, we first investigated the phytochemical changes during the blueberry fermentation process. Fermentation favored the release of oligomers and bioactive compounds such as protocatechuic acid (PCA), gallic acid, and catechol. Next, we investigated the chemopreventive potentials of a polyphenolic mixture containing PCA, gallic acid, and catechin found in fermented blueberry juice in a breast cancer model by measuring miRNA expression and the signaling pathways involved in breast cancer stemness and invasion. To this end, 4T1 and MDA-MB-231 cell lines were treated with different doses of the polyphenolic mixture for 24 h. Additionally, female Balb/c mice were fed with this mixture for five weeks; two weeks before and three weeks after receiving 4T1 cells. Mammosphere formation was assayed in both cell lines and the single-cell suspension obtained from the tumor. Lung metastases were counted by isolating 6-thioguanine-resistant cells present in the lungs. In addition, we conducted RT-qPCR and Western blot analysis to validate the expression of targeted miRNAs and proteins, respectively. We found a significant reduction in mammosphere formation in both cell lines treated with the mixture and in tumoral primary cells isolated from mice treated with the polyphenolic compound. The number of colony-forming units of 4T1 cells in the lungs was significantly lower in the treatment group compared to the control group. miR-145 expression significantly increased in the tumor samples of mice treated with the polyphenolic mixture compared to the control group. Furthermore, a significant increase in FOXO1 levels was noted in both cell lines treated with the mixture. Overall, our results show that phenolic compounds found in fermented blueberry delay the formation of tumor-initiating cells in vitro and in vivo and reduce the spread of metastatic cells. The protective mechanisms seem to be related, at least partly, to the epigenetic modulation of mir-145 and its signaling pathways.

The function of miR-145 in colorectal cancer progression; an updated review on related signaling pathways

MicroRNAs (miRNA) are a broad class of small, highly conserved non-coding RNAs that largely influence gene expression after transcription through binding to various target mRNAs. miRNAs are frequently dysregulated in a wide array of human cancers, possessing great value as diagnostic and therapeutic targets. miR-145, as promising tumor suppressor miRNA, also exhibits deregulated expression levels in human malignancies and participates in various processes, including cell proliferation, apoptosis, migration and differentiation. In particular, miR-145 has been shown to be downregulated in colorectal cancer (CRC), which in turn leads to cell growth, invasion, metastasis and drug resistance. Furthermore, miR-145 is involved in the regulation of multiple tumor specific signaling pathways, such as KRAS and P53 signaling by targeting various genes through colorectal tumorigenesis. Therefore, considering its diagnostic and therapeutic potential, it was aimed to present the recent finding focusing on miR-145 functions to better understand its involvement in CRC incidence and progression through interplay with various signaling pathways. This study is based on articles indexed in PubMed and Google scholar until 2021.

A miRNA-Based Prognostic Model to Trace Thyroid Cancer Recurrence

Simple Summary

Some thyroid tumors elected for surveillance remain indolent, while others progress. The mechanism responsible for this difference is poorly understood, making it challenging to devise patient surveillance plans. Early prediction is important for tailoring treatment and follow-up in high-risk patients. The aim of our study was to identify predictive markers for progression. We leveraged a highly sensitive test that accurately predicts which thyroid nodules are more likely to develop lymph node metastasis, thereby improving care and outcomes for cancer patients.

Abstract

Papillary thyroid carcinomas (PTCs) account for most endocrine tumors; however, screening and diagnosing the recurrence of PTC remains a clinical challenge. Using microRNA sequencing (miR-seq) to explore miRNA expression profiles in PTC tissues and adjacent normal tissues, we aimed to determine which miRNAs may be associated with PTC recurrence and metastasis. Public databases such as TCGA and GEO were utilized for data sourcing and external validation, respectively, and miR-seq results were validated using quantitative real-time PCR (qRT-PCR). We found miR-145 to be significantly downregulated in tumor tissues and blood. Deregulation was significantly related to clinicopathological features of PTC patients including tumor size, lymph node metastasis, TNM stage, and recurrence. In silico data analysis showed that miR-145 can negatively regulate multiple genes in the TC signaling pathway and was associated with cell apoptosis, proliferation, stem cell differentiation, angiogenesis, and metastasis. Taken together, the current study suggests that miR-145 may be a biomarker for PTC recurrence. Further mechanistic studies are required to uncover its cellular roles in this regard.

Treatment of Resectable Gallbladder Cancer

Gallbladder cancer (GBC) is the most common biliary tract cancer worldwide and its incidence has significant geographic variation. A unique combination of predisposing factors includes genetic predisposition, geographic distribution, female gender, chronic inflammation, and congenital developmental abnormalities. Today, incidental GBC is the most common presentation of resectable gallbladder cancer, and surgery (minimally invasive or open) remains the only curative treatment available. Encouragingly, there is an important emerging role for systemic treatment for patients who have R1 resection or present with stage III-IV. In this article, we describe the pathogenesis, surgical and systemic treatment, and prognosis.

5,7,2,5-tetrahydroxy-8,6-dimethoxyflavone up-regulates miR-145 expression and inhibits proliferation of gastric cancer cells

INTRODUCTION

Gastric cancer is a frequently detected malignancy, and its incidence has increased over the past decades in East Asia. The present study investigated the effect of 5,7,2, 5-tetrahydroxy-8,6-dimethoxyflavone (THDMF) on gastric cancer cells and explored the underlying mechanism. The study analysed cell viability changes, apoptotic features, and metastasis potential of treatment with THDMF.

MATERIAL AND METHODS

MTT colorimetric assay was used for measurement of MKN28, MKN45, and GES-1 cell proliferation and flow cytometry for the detection of apoptosis. Transwell and wound healing assays were used to observe the invasion and migration abilities of MKN28 cells. The expression of p21, MMP2/-9, PI3K, and c-Myc proteins was detected by western blotting.

RESULTS

The THDMF treatment significantly (p < 0.05) reduced MKN28 and MKN45 cell proliferation without changing GES-1 cell viability. A significant increase in apoptotic cell population on treatment with THDMF was observed. Treatment of MKN28 cells with THDMF increased the percentage of cells in the G1 phase. Exposure of MKN28 cells to THDMF caused a marked decrease in invasion and migration potential in comparison to control cells. The expression of miR-145 was markedly increased in MKN28 cells on treatment with THDMF. In MKN28 cells expression of c-Myc, PI3K, p-AKT, MMP-2, and MMP-9 was suppressed markedly on exposure to THDMF. The expression of p21 protein in MKN28 cells was markedly promoted on exposure to THDMF.

CONCLUSIONS

THDMF exhibits anti-cancer effect on gastric cancer cells in vitro by activation of cell apoptosis and arrest of cell cycle. In addition, THDMF promoted miR-145 expression and down-regulation of PI3K/AKT signalling pathway in MKN28 cells. Therefore, THDMF may be utilised as a potential novel therapeutic agent for the treatment of gastric cancer.

Identification and verification of the molecular mechanisms and prognostic values of the cadherin gene family in gastric cancer

While cadherin (CDH) genes are aberrantly expressed in cancers, the functions of CDH genes in gastric cancer (GC) remain poorly understood. The clinical significance and molecular mechanisms of CDH genes in GC were assessed in this study. Data from a total of 1226 GC patients included in The Cancer Genome Atlas (TCGA) and Kaplan–Meier plotter database were used to independently explore the value of CDH genes in clinical application. The TCGA RNA sequencing dataset was used to explore the molecular mechanisms of CDH genes in GC. Using enrichment analysis tools, CDH genes were found to be related to cell adhesion and calcium ion binding in function. In TCGA cohort, 12 genes were found to be differentially expressed between GC para-carcinoma and tumor tissue. By analyzing GC patients in two independent cohorts, we identified and verified that CDH2, CDH6, CDH7 and CDH10 were significantly associated with a poor GC prognosis. In addition, CDH2 and CDH6 were used to construct a GC risk score signature that can significantly improve the accuracy of predicting the 5-year survival of GC patients. The GSEA approach was used to explore the functional mechanisms of the four prognostic CDH genes and their associated risk scores. It was found that these genes may be involved in multiple classic cancer-related signaling pathways, such as the Wnt and phosphoinositide 3-kinase signaling pathways in GC. In the subsequent CMap analysis, three small molecule compounds (anisomycin, nystatin and bumetanide) that may be the target molecules that determine the risk score in GC, were initially screened. In conclusion, our current study suggests that four CDH genes can be used as potential biomarkers for GC prognosis. In addition, a prognostic signature based on the CDH2 and CDH6 genes was constructed, and their potential functional mechanisms and drug interactions explored.

MicroRNA as an Important Target for Anticancer Drug Development

Cancer has become the second greatest cause of death worldwide. Although there are several different classes of anticancer drugs that are available in clinic, some tough issues like side-effects and low efficacy still need to dissolve. Therefore, there remains an urgent need to discover and develop more effective anticancer drugs. MicroRNAs (miRNAs) are a class of small endogenous non-coding RNAs that regulate gene expression by inhibiting mRNA translation or reducing the stability of mRNA. An abnormal miRNA expression profile was found to exist widely in cancer cell, which induces limitless replicative potential and evading apoptosis. MiRNAs function as oncogenes (oncomiRs) or tumor suppressors during tumor development and progression. It was shown that regulation of specific miRNA alterations using miRNA mimics or antagomirs can normalize the gene regulatory network and signaling pathways, and reverse the phenotypes in cancer cells. The miRNA hence provides an attractive target for anticancer drug development. In this review, we will summarize the latest publications on the role of miRNA in anticancer therapeutics and briefly describe the relationship between abnormal miRNAs and tumorigenesis. The potential of miRNA-based therapeutics for anticancer treatment has been critically discussed. And the current strategies in designing miRNA targeting therapeutics are described in detail. Finally, the current challenges and future perspectives of miRNA-based therapy are conferred.

Vitamin D modulation and microRNAs in gastric cancer: prognostic and therapeutic role

Gastric adenocarcinoma arises after a complex interaction between the host and environmental factors. Tumor location and TNM are the tools that currently guide treatment decisions. Surgery is the only curative treatment, but relapse is common. After relapse or advanced staged disease survival is poor and systemic treatment has modestly improved survival. An association between sun exposure, vitamin D status and gastric cancer (GC) incidence and mortality has been reported. The molecular differences of the histological subtypes and the new molecular classifications account for the great heterogeneity of this disease and are the basis for the discovery of new therapeutic targets. New prognostic and predictive factors are essential and microRNAs (miRNAs) are endogenous small non-coding RNA molecules with a great potential for diagnosis, prognosis and treatment of cancer. There are hundreds of miRNAs with altered expression in tumor gastric tissue when compared to normal gastric tissue. Many of these miRNAs are associated with clinicopathological variables and survival in patients with GC. Furthermore, the expression of some of these miRNAs with prognostic importance in CG is influenced by vitamin D and others are mediators of some of the actions of this vitamin. This review aims to update the evidence on several miRNAs with prognostic value and therapeutic potential in GC, whose expression may be influenced by vitamin D or may regulate vitamin D signaling.

MicroRNA Changes in Gastric Carcinogenesis: Differential Dysregulation during Helicobacter pylori and EBV Infection

Despite medical advances, gastric-cancer (GC) mortality remains high in Europe. Bacterial infection with Helicobacter pylori (H. pylori) and viral infection with the Epstein–Barr virus (EBV) are associated with the development of both distal and proximal gastric cancer. Therefore, the detection of these infections and the prediction of further cancer development could be clinically significant. To this end, microRNAs (miRNAs) could serve as promising new tools. MiRNAs are highly conserved noncoding RNAs that play an important role in gene silencing, mainly acting via translational repression and the degradation of mRNA targets. Recent reports demonstrate the downregulation of numerous miRNAs in GC, especially miR-22, miR-145, miR-206, miR-375, and miR-490, and these changes seem to promote cancer-cell invasion and tumor spreading. The dysregulation of miR-106b, miR-146a, miR-155, and the Let-7b/c complex seems to be of particular importance during H. pylori infection or gastric carcinogenesis. In contrast, many reports describe changes in host miRNA expression and outline the effects of bamHI-A region rightward transcript (BART) miRNA in EBV-infected tissue. The differential regulation of these miRNA, acting alone or in close interaction when both infections coexist, may therefore enable us to detect cancer earlier. In this review, we focus on the two different etiologies of gastric cancer and outline the molecular pathways through which H. pylori- or EBV-induced changes might synergistically act via miR-155 dysregulation to potentiate cancer risk. The three markers, namely, H. pylori presence, EBV infection, and miR-155 expression, may be checked in routine biopsies to evaluate the risk of developing gastric cancer.

LncRNA GNAS-AS1 facilitates ER+ breast cancer cells progression by promoting M2 macrophage polarization via regulating miR-433-3p/GATA3 axis

Objective: ER⁺ breast cancer is the most common type of breast cancer, which seriously affects the physical and mental health of women. Recently, lncRNAs mediated tumor-associated macrophages (TAM) were identified to involve in tumorigenesis. Therefore, the present study aimed at demonstrating the regulatory network of GNAS-AS1 in TAM-mediated ER⁺ breast cancer progress.

Methods: The expression levels of genes were evaluated using qRT-PCR. The proportions of polarized macrophages (M1, M2) were assessed by flow cytometry. Cell proliferation, migration and invasion were evaluated by CCK-8, wound healing and transwell assay, respectively. Double-luciferase reporter system was used to detect the interaction between molecules. Western blot was applied to test protein levels.

Results: The expression of GNAS-AS1 was obviously increased in ER⁺ breast cancer tissues and cell lines, as well as M2 macrophages. GNAS-AS1 facilitated the capabilities of proliferation, migration and invasion of ER⁺ breast cancer cells by accelerating M2 macrophage polarization via directly sponging miR-433-3p. GATA3, as a target of miR-433-3p, could positively regulate by GNAS-AS1. Furthermore, either miR-433-3p overexpression or GATA3 knockdown impaired the effects of GNAS-AS1 on M2 macrophage polarization and ER⁺ breast cancer cells progression.

Conclusion: GNAS-AS1/miR-433-3p/GATA3 axis promoted proliferation, metastasis of ER⁺ breast cancer cells by accelerating M2 macrophage polarization. The mechanism may provide a new strategy and target for ER⁺ breast cancer treatment.

Long non-coding RNA KCNQ1OT1 promotes the progression of gastric cancer via the miR-145-5p/ARF6 axis

Background

Long non‐coding RNA KCNQ1 opposite strand/antisense transcript one gene (KCNQ1OT1) has been reported to be involved in the progression of many types of human cancer, whereas its role in gastric cancer (GC) remains unknown. The present study aimed to investigate the role of KCNQ1OT1 in GC.

Methods

In total, 25 GC tissues and adjacent normal tissues were collected. The expression of KCNQ1OT1, miR‐145‐5p and ARF6 in GC tissues and cell lines was detected by quantitative reverse transcriptase‐polymerase chain reaction or western blotting. Bioinformatics analysis and a dual luciferase reporter assay were performed to determine the relationship between KCNQ1OT1 and miR‐145‐5p or miR‐145‐5p and ARF6. Gain‐ and loss‐of function of KCNQ1OT1 and miR‐145‐5p were achieved to confirm their roles in GC cells. Cell counting kit‐8, colony formation and flow cytometry assays were used to evaluate cell viability, proliferation and apoptosis. A xenograft tumor model was established with BGC803 tumor cells transfected with sh‐KCNQ1OT1 or empty vector to determine the role of LINC01089 in vivo.

Results

The expression levels of KCNQ1OT1 were markedly elevated in GC tissues and cells. Knockdown of KCNQ1OT1 inhibited GC tumor growth, reduced GC cell viability and colony formation, and induced GC cell apoptosis. The expression levels of miR‐145‐5p were significantly decreased in GC cells and correlated with the expression of KCNQ1OT1 in GC tumors. Moreover, KCNQ1OT1 directly binds with miR‐145‐5p, which is targeting ARF6. Knockdown of KCNQ1OT1 increased the expression levels of miR‐145‐5p. Inhibition of miR‐145‐5p increased the expression levels of KCNQ1OT1 and also attenuated the effects of knockdown of KCNQ1OT1 on the viability, proliferation and apoptosis of GC cells. In addition, overexpression of miR‐145‐5p reduced GC cell viability and colony formation and induced GC cell apoptosis, whereas overexpression of ARF6 attenuated the effects of overexpression of miR‐145‐5p on GC cell viability, colony formation and apoptosis.

Conclusions

KCNQ1OT1 can promote GC progression through the miR‐145‐5p/ARF6 axis. KCNQ1OT1 may serve as a therapeutic target and a diagnostic biomarker of GC.

MiR-19a/miR-96-mediated low expression of KIF26A suppresses metastasis by regulating FAK pathway in gastric cancer

Gastric cancer (GC) is one of the most common malignant neoplasms. Invasion and metastasis are the main causes of GC-related deaths. Recently, kinesins were discovered to be involved in tumor development. The aim of this study was to elucidate the roles of kinesin superfamily protein 26A (KIF26A) in GC and its underlying molecular mechanism in regulating tumor invasion and metastasis. Using real-time quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC), we showed that KIF26A expression was lower in GC tissues without lymph node metastasis (LNM) than in nontumorous gastric mucosa, and even lower in GC tissues with LNM than in GC tissues without LNM. Functional experiments showed that KIF26A inhibited migration and invasion of GC cells. We further identified focal-adhesion kinase (FAK), phosphatidylinositol 3-kinase regulatory subunit alpha (PI3KR1), VAV3, Rac1 and p21-activated kinase 2, and β-PAK (PAK3) as downstream effectors of KIF26A in the focal-adhesion pathway, and we found that KIF26A could regulate FAK mRNA expression through inhibiting c-MYC by MAPK pathway. c-MYC could bind to the promoter of FAK and activate FAK transcription. Moreover, we found that KIF26A-mediated inactivation of the focal-adhesion pathway could reduce the occurrence of the epithelial-to-mesenchymal transition (EMT) by increasing expression of E-cadherin and reducing that of Snail. Luciferase assays and Western blotting revealed that miR-19a and miR-96 negatively regulate KIF26A. Finally, we found that decreased expression of KIF26A has been positively correlated with histological differentiation, Lauren classification, LNM, distal metastasis, and clinical stage, as well as poor survival in patients with GC. These data indicate that KIF26A could inhibit GC migration and invasion by regulating the focal-adhesion pathway and repressing the occurrence of EMT.

Involvement of APRIL in Helicobacter pylori-related gastric cancer

BACKGROUND/AIMS

A proliferation-inducing ligand (APRIL, also known as TNFSF13, CD256) is a member of the tumor necrosis factor (TNF) superfamily and involved in a diverse set of diseases. In this work, we explored the potential associations and underlying mechanism in patients suffered from gastric cancer between the expression of APRIL and H. pylori infection.

METHODS

We analyzed APRIL expression levels in 200 GC tissue samples by immunohistochemistry staining. H. pylori infection was detected by modified Giemsa staining. The biological effects of APRIL on human GC cells in vitro and in vivo were tested by CCK-8 assay, colony formation, flow cytometry detection, transwell migration assay, matrigel invasion assay, and tumor xenograft assay in animals.

RESULTS

APRIL reactivity was positively correlated with H. pylori infection in vitro and vivo. It turned out that the decrease of miR-145 expression was dose-dependent and time-dependent on H. pylori infection and in consistent with APRIL expression. MiR-145 significantly attenuated the effect of H. pylori infection on APRIL gene expression in SGC7901 and BGC823 cell lines. Furthermore, APRIL overexpression promoted the proliferation, migration, invasion, and transfer of GC cells and decreased apoptosis, while APRIL knockdown suppressed these effects. We confirmed that APRIL activated the canonical NF-κB pathway through phosphorylation of AKT.

CONCLUSION

The expression of APRIL, which promoted the proliferation, migration, invasion, viability, and metastasis of GC cells, was upregulated in human H. pylori-infected GC through miR-145. Besides, APRIL-induced gastric tumorigenicity via activating NF-κB pathway. These results may provide a framework for the deeper analysis of APRIL in GC risk and prognosis.

sMicroRNA-28-5p acts as a metastasis suppressor in gastric cancer by targeting Nrf2

The transcription factor nuclear factor (erythroid-2)-related factor 2 (Nrf2) can principally serve a mode of protection for both the normal cells and cancer cells from cellular stress, and elevates cancer cell survival. microRNA-28 (miR-28) has been involved in the regulation of Nrf2 expression in breast epithelial cells. However, no comprehensive analysis has been conducted regarding the function of miR-28-5p regulating Nrf2 in gastric cancer (GC). In this study, we aimed to evaluate their interaction and biological roles in the migration and invasion of GC cells. The expression of Nrf2 in the cancer tissues harvested from 42 patients with GC was examined by an array of molecular techniques comprising of Immunohistochemical staining, RT-qPCR and Western blot analysis. Kaplan-Meier method was adopted for analysis of the correlation of Nrf2 with the prognosis of GC patients. Interaction between miR-28-5p and Nrf2 was determined using the bioinformatics analysis and dual luciferase reporter gene assay. Gain- and loss-of-function studies of miR-28-5p and Nrf2 were conducted to elucidate their effects on GC cell migration, invasion and metastasis, as well as expression pattern of several epithelial-mesenchymal transition (EMT)-related proteins. Results indicated that the expression pattern of Nrf2 was significantly upregulated in GC tissues and indicative of poor prognosis of GC patients. miR-28-5p was verified to target Nrf2 and downregulate its expression. GC cells with overexpression of miR-28-5p or Nrf2 knockdown exhibited a marked reduction in the migrated and invasive abilities, along with the N-cadherin expression yet an increase of E-cadherin expression. Furthermore, miR-28-5p exerted an inhibitory function on the metastatic and tumorigenicity of GC cells. In conclusion, miR-28-5p is a comprehensive tumor suppressor that inhibits GC cell migration and invasion through repressing the Nrf2 expression. Therefore, miR-28-5p may serve as a potential biomarker for the prognosis of GC and a novel therapeutic target in advanced GC.

Regulators at Every Step-How microRNAs Drive Tumor Cell Invasiveness and Metastasis

Simple Summary

Tumor cell invasiveness and metastasis are key processes in cancer progression and are composed of many steps. All of them are regulated by multiple microRNAs that either promote or suppress tumor progression. Multiple studies demonstrated that microRNAs target the mRNAs of multiple genes involved in the regulation of cell motility, local invasion, and metastatic niche formation. Thus, microRNAs are promising biomarkers and therapeutic targets in oncology.

Abstract

Tumor cell invasiveness and metastasis are the main causes of mortality in cancer. Tumor progression is composed of many steps, including primary tumor growth, local invasion, intravasation, survival in the circulation, pre-metastatic niche formation, and metastasis. All these steps are strictly controlled by microRNAs (miRNAs), small non-coding RNA that regulate gene expression at the post-transcriptional level. miRNAs can act as oncomiRs that promote tumor cell invasion and metastasis or as tumor suppressor miRNAs that inhibit tumor progression. These miRNAs regulate the actin cytoskeleton, the expression of extracellular matrix (ECM) receptors including integrins and ECM-remodeling enzymes comprising matrix metalloproteinases (MMPs), and regulate epithelial–mesenchymal transition (EMT), hence modulating cell migration and invasiveness. Moreover, miRNAs regulate angiogenesis, the formation of a pre-metastatic niche, and metastasis. Thus, miRNAs are biomarkers of metastases as well as promising targets of therapy. In this review, we comprehensively describe the role of various miRNAs in tumor cell migration, invasion, and metastasis.

Regulators at Every Step—How microRNAs Drive Tumor Cell Invasiveness and Metastasis

Tumor cell invasiveness and metastasis are the main causes of mortality in cancer. Tumor progression is composed of many steps, including primary tumor growth, local invasion, intravasation, survival in the circulation, pre-metastatic niche formation, and metastasis. All these steps are strictly controlled by microRNAs (miRNAs), small non-coding RNA that regulate gene expression at the post-transcriptional level. miRNAs can act as oncomiRs that promote tumor cell invasion and metastasis or as tumor suppressor miRNAs that inhibit tumor progression. These miRNAs regulate the actin cytoskeleton, the expression of extracellular matrix (ECM) receptors including integrins and ECM-remodeling enzymes comprising matrix metalloproteinases (MMPs), and regulate epithelial–mesenchymal transition (EMT), hence modulating cell migration and invasiveness. Moreover, miRNAs regulate angiogenesis, the formation of a pre-metastatic niche, and metastasis. Thus, miRNAs are biomarkers of metastases as well as promising targets of therapy. In this review, we comprehensively describe the role of various miRNAs in tumor cell migration, invasion, and metastasis.

Overexpression of miRNA-145 induces apoptosis and prevents proliferation and migration of MKN-45 gastric cancer cells

MiR-145 is a tumor suppressor miRNA that its ubiquitously expressed in the body but in numerous types of cancers such as GC, its expression became reduced or sometimes ceased in many subjects. This study aimed at restoring the function of the miR-145 in MKN-45 cells and investigating the function of this miRNA in proliferation, apoptosis, and migration of GC cells. MKN-45 cells were transfected using the PCMV-miR-145 plasmid vector. The MTT, DAPI staining, and wound healing assays were applied to estimate the impacts of ectopic expression of miR-145 in vitro. Moreover, alterations in the expression levels of K-Ras, c-Myc, caspase-3, caspase-9, Bax, Bcl-2, and MMP-9 mRNA were measured by qRT-PCR analysis. The findings designated that high expression of miR-145 reduced the proliferation and migration and increased the apoptosis of the MKN-45 cells. These effects occur with concurrent suppression of c-Myc, K-Ras, Bcl-2, and MMP-9 as well as induction of caspase-3, caspase-9, and Bax expression. Exogenous miR-145 influences multiple oncogenic pathways and can be regarded as a promising avenue of future therapeutic interventions for GC therapy.

Circulating microRNA-145 as a diagnostic biomarker for non-small-cell lung cancer: A systemic review and meta-analysis

BACKGROUND

MicroRNAs (miRNAs), a class of small non-coding, highly stable RNAs, have been reported to have diagnostic value for variety types of cancers.

OBJECTIVES

To assess the diagnostic value of circulating miR-145 for non-small cell lung cancer (NSCLC) by using systemic review and meta-analysis.

METHODS

A systematic literature search was conducted in five databases until 20 February 2020 to identify diagnostic trials of miR-145 in the diagnosis of NSCLC. The quality of included studies was assessed by the QUADAS-2 tool with Review Manager 5.3, and the summary receiver operating characteristic (SROC) curve was plotted by STATA 13.1 software.

RESULTS

A total of 1394 patients from 11 data sets in trials (published in nine studies) were recruited. The area under the curve of the SROC was 0.83. According to the meta regression, the specimen selection was considered the source of heterogeneity, the SROC in serum (0.90 (95% CI 0.87, 0.92), the sensitivity was 0.84 (95% CI 0.79, 0.89), and the specificity was 0.80 (95% CI 0.71, 0.89)) was obviously higher than that in plasma (SROC=0.75).

CONCLUSION

Serum miR-145 might be served as a potentially useful biomarker for NSCLC diagnosis. However, due to the existing limited-quality research, more large-scale and multicenter studies are required for further verification.

Bacterial SOS Genes mucAB/umuDC Promote Mouse Tumors by Activating Oncogenes Nedd9/Aurkb via a miR-145 Sponge

The mechanism of cancer induction involves an aberrant expression of oncogenes whose functions can be controlled by RNAi with miRNA. Even foreign bacterial RNA may interfere with the expression of oncogenes. Here we show that bacterial plasmid mucAB and its Escherichia coli genomic homolog umuDC, carrying homologies that match the mouse anti-miR-145, sequestered the miR-145 function in mouse BALB 3T3 cells in a tetracycline (Tet)-inducible manner, activated oncogene Nedd9 and its downstream Aurkb, and further enhanced microcolony formation and cellular transformation as well as the short fragments of the bacterial gene containing the anti-miR-145 sequence. Furthermore, mucAB transgenic mice showed a 1.7-fold elevated tumor incidence compared with wild-type mice after treatments with 3-methylcolanthrene. However, the mutation frequency in intestinal stem cells of the mucAB transgenic mice was unchanged after treatment with X-rays or ethyl-nitrosourea, indicating that the target of mucAB/umuDC is the promotion stage in carcinogenesis. IMPLICATIONS: Foreign bacterial genes can exert oncogenic activity via RNAi, if endogenously expressed. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/18/9/1271/F1.large.jpg.

E2F1-activated SPIN1 promotes tumor growth via a MDM2-p21-E2F1 feedback loop in gastric cancer

Gastric cancer (GC) is one of the most common cancers around the world. Searching for specific gene expression changes during the development of GC could help identify potential therapy targets. We previously showed that the histone code reader SPIN1 may act as an oncogene in breast cancer. At present, the biological function and regulation of SPIN1 in GC remain unclear. Here, we demonstrate that SPIN1 is upregulated in GC tissues, compared with nontumorous gastric tissues. Increased expression of SPIN1 is closely associated with poor prognosis for patients with GC. Increased SPIN1 expression enhances GC cell proliferation, migration, and invasion and promotes cell cycle progression. Mechanically, SPIN1 sustains GC cell proliferation via activation of the MDM2-p21-E2F1 signaling pathway by binding to H3K4me3 of the MDM2 promoter region. Interestingly, E2F1 could directly bind to the SPIN1 promoter and activate its transcription, thus forming a positive feedback loop. Our data suggest that SPIN1 plays an important role in the development of GC and could be used as a promising prognostic biomarker and therapeutic target for GC.

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.

Silencing of long non-coding RNA Sox2ot inhibits oxidative stress and inflammation of vascular smooth muscle cells in abdominal aortic aneurysm via microRNA-145-mediated Egr1 inhibition

Long non-coding RNAs (lncRNAs) have been largely reported to contribute to the development and progression of abdominal aortic aneurysm (AAA), a common vascular degenerative disease. The present study was set out with the aim to investigate the possible role of lncRNA Sox2ot in the development of AAA. In this study, we found that lncRNA Sox2ot and early growth response factor-1 (Egr1) were highly expressed, while microRNA (miR)-145 was poorly expressed in Ang II-induced AAA mice and oxidative stress-provoked vascular smooth muscle cell (VSMC) model. Egr1 was a potential target gene of miR-145, and lncRNA Sox2ot could competitively bind to miR-145 to upregulate Egr1 expression. Overexpression of miR-145-5p was found to attenuate oxidative stress and inflammation by inhibiting Egr1 both in vivo and in vitro, which was counteracted by lncRNA Sox2ot. Taken together, the present study provides evidence that downregulation of lncRNA Sox2ot suppressed the expression of Egr1 through regulating miR-145, thus inhibiting the development of AAA, highlighting a theoretical basis for AAA treatment.

Allicin suppresses growth and metastasis of gastric carcinoma: the key role of microRNA-383-5p-mediated inhibition of ERBB4 signaling

Allicin is a natural product suppressing the progression of gastric carcinoma (GC). In the current study, the mechanism underlying the anti-GC effect of allicin was explored by focusing on the role of miR-383-5p/ERBB4 signaling. Two GC cell lines were treated with allicin and the effects on viability, apoptosis, migration, invasion, and miR-383-5p/ERBB4 activity in the cells were assessed. The interaction between allicin and miR-383-5p was further explored by inhibiting the miR-383-5p level. Allicin suppressed cell viability and induced apoptosis in both GC cell lines. The compound also inhibited migration and invasion of GC cells, which was associated with the up-regulation miR-383-5p and down-regulation of ERBB4. The inhibition of miR-383-5p by specific inhibitor blocked the anti-GC effect of allicin. Our results demonstrated that allicin contributed to the suppressed growth and metastasis potentials in GC cell lines. The effect was accompanied by an increased level of miR-383-5p and subsequent inhibition of ERBB4.

DNA Methylation Influences miRNA Expression in Gonadotroph Pituitary Tumors

microRNAs are involved in pathogenesis of cancer. DNA methylation plays a role in transcription of miRNA-encoding genes and may contribute to changed miRNA expression in tumors. This issue was not investigated in pituitary neuroendocrine tumors (PitNETs) previously. DNA methylation patterns, assessed with HumanMethylation450K arrays in 34 PitNETs and five normal pituitaries, were used to determine differentially methylated CpGs located at miRNA genes. It showed aberrant methylation in regions encoding for 131 miRNAs. DNA methylation data and matched miRNA expression profiles, determined with next-generation sequencing (NGS) of small RNAs, were correlated in 15 PitNETs. This showed relationship between methylation and expression levels for 12 miRNAs. DNA methylation and expression levels of three of them (MIR145, MIR21, and MIR184) were determined in the independent group of 80 tumors with pyrosequencing and qRT-PCR and results confirmed both aberrant methylation in PitNETs and correlation between methylation and expression. Additionally, in silico target prediction was combined with analysis of established miRNA profiles and matched mRNA expression pattern, assessed with amplicon-based NGS to indicate putative target genes of epigenetically deregulated miRNAs. This study reveals aberrant DNA methylation in miRNA-encoding genes in gonadotroph PitNETs. Methylation changes affect expression level of miRNAs that regulate putative target genes with tumorigenesis-relevant functions.

Clinical and prognostic association of oncogene cadherin 11 in gastric cancer

The abnormal expression of cadherin-11 (CDH11) affects the progression of several types of cancer. However, the expression pattern and prognostic value of CDH11 in gastric cancer (GC) have not been reported. In the present study, the expression of CDH11 in patients with GC and its effect on their survival were analyzed using public cancer databases. The expression of CDH11 in GC tissues was significantly higher compared with that in normal gastric tissues. The expression of CDH11 was higher in advanced GC compared with early GC, and increased CDH11 was associated with tumor progression and poor prognosis in patients with GC. The high level of methylation in the promoter of CDH11 in GC tissues was not sufficient to reverse the upregulation of CDH11 caused by transcriptional activation. Finally, the expression pattern and prognostic significance of CDH11 in GC were validated using data from patients with GC recruited for the present study. Collectively, the present results demonstrated that CDH11 was upregulated in GC tissues, and suggested that high CDH11 expression may be associated with progression and poor prognosis in GC.

Functional implications of miR-145/RCAN3 axis in the progression of cervical cancer

Cervical cancer, as the second leading cause of death in women malignant tumor, is not optimistic about survival rate and late recurrence rate. RCAN3 has been reported to function in a variety of diseases, but its relationship with cervical cancer has not been reported. This study aimed to investigate whether RCAN3 contributes to the development of cervical cancer and its mechanism. RCAN3 expression was analyzed in 306 cervical cancer tissues and 13 normal healthy tissues from TCGA and GTEX databases. Kaplan-Meier analysis and Cox regression analysis were carried out to assess the potential function of RCAN3. Subsequently, the upstream regulatory miRNA of RCAN3 was predicted by bioinformatics and confirmed using dual luciferase reporter assay. CCK-8, colony formation assay, transwell assay were used for functional analysis of miR-145/RCAN3 axis in vitro. The results showed that RCAN3 was highly expressed in cervical cancer tissues, leading to poor prognosis, and could be used as a prognostic factor for cervical cancer. MiR-145 directly targeted RCAN3, which was lowly expressed in cervical cancer tissues and cell lines, and the higher the miR-145 expression, the longer the survival time of patients. Finally, from the functional experiments results we can see that miR-145 can inhibit the proliferation, migration and invasion of cervical cancer cells, but overexpression of RCAN3 can reverse miR-145-mediated inhibition. To sum up, miR-145/RCAN3 axis may serve as a potential therapeutic target to regulate the progression of cervical cancer.

Down-regulation of lncRNA LINC00152 Suppresses Gastric Cancer Cell Migration and Invasion Through Inhibition of the ERK/MAPK Signaling Pathway

Purpose

The aim of this study was to explore the regulatory role and mechanism of long noncoding RNA LINC00152 in gastric cancer (GC) cells.

Methods

LINC00152 expression in GC tissues and cells was detected by reverse transcription-polymerase chain reaction (qRT-PCR). MKN45 and MGC-803 cells were selected and assigned into different groups after transfection with si-LINC00152, activated ERK/MAPK signaling pathway (SA), or negative control. Cell proliferation, apoptosis, cycle, migration and invasion were assessed by CCK-8, flow cytometry, Transwell assay and Scratch test, respectively. Western blot analysis was conducted to detect the expression of E-cadherin, N-cadherin and ERK/MAPK signaling pathway protein.

Results

Compared with the normal tissues, higher expression of LINC00152 was found in GC tissues and LINC00152 was remarkably correlative with clinical stage and lymphatic metastasis. LINC00152 expression in GC cells was higher than that in GES-1 cells. Compared with the NC group, the cell proliferation rate, cells in G2/M phase, migration and invasion abilities as well as the expression of N-cadherin and p-ERK-1/2 were significantly decreased, and the expression of E-cadherin, cells in G0/G1 phase and cell apoptosis rate were significantly increased in the si-LINC00152-1 group. ERK/MAPK signaling pathway activator SA could reverse the biological role of LINC00152 in GC cells.

Conclusion

These results demonstrated that the interference of LINC00152 expression may inhibit the invasion and migration of GC cells by inhibiting the ERK/MAPK signaling pathway.

The Role of MicroRNAs upon Epithelial-to-Mesenchymal Transition in Inflammatory Bowel Disease

Increasing evidence suggest the significance of inflammation in the progression of cancer, for example the development of colorectal cancer in Inflammatory Bowel Disease (IBD) patients. Long-lasting inflammation in the gastrointestinal tract causes serious systemic complications and breaks the homeostasis of the intestine, where the altered expression of regulatory genes and miRNAs trigger malignant transformations. Several steps lead from acute inflammation to malignancies: epithelial-to-mesenchymal transition (EMT) and inhibitory microRNAs (miRNAs) are known factors during multistage carcinogenesis and IBD pathogenesis. In this review, we outline the interactions between EMT components and miRNAs that may affect cancer development during IBD.

Genome-wide analysis to identify a novel microRNA signature that predicts survival in patients with stomach adenocarcinoma

Objective: Using genome-wide screening, this study was aimed at identifying prognostic microRNA (miRNA) in those patients suffering from stomach adenocarcinoma (STAD).

Methods: A genome-wide miRNA sequencing dataset and relevant STAD clinical information was obtained via The Cancer Genome Atlas (TCGA). Prognostic miRNA selection was carried out through a whole genome multivariate Cox regression model in order to establish a prognostic STAD signature.

Results: Eleven miRNAs (hsa-mir-509-2, hsa-mir-3917, hsa-mir-495, hsa-mir-653, hsa-mir-3605, hsa-mir-2115, hsa-mir-1292, hsa-mir-137, hsa-mir-6511b-1, hsa-mir-145, and hsa-mir-138-2) were recognized as prognostic and used for the construction of a STAD prognostic signature. This signature exhibited good performance in predicting prognosis (adjusted P<0.0001, adjusted hazard ratio= 3.047, and 95% confidence interval=2.148-4.323). The time-dependent receiver operating characteristic examination exhibited area under curve values of 0.711, 0.697, 0.716, 0.733, 0.805, and 0.805, for 1-, 2-, 3-, 4-, 5-, and 10-year overall survival (OS) estimation, respectively. Comprehensive survival analysis suggests that the 11-miRNA prognostic signature acts as an independent feature of STAD prognosis and exhibits superior performance in OS prediction when compared to traditional clinical parameters. Furthermore, fourteen miRNA target genes were linked to STAD OS. These included SERPINE1, MLEC, ANGPT2, C5orf38, FZD7, MARCKS, PDGFD, DUSP6, IRS1, PSAT1, TENM3, TMEM127, BLMH, and TIRAP. Functional and gene set enrichment analysis suggested that target genes and the 11-miRNA prognostic signature were both participate in various biological processes and pathways, including the growth factor beta, Wnt, and Notch signaling pathways.

Conclusions: By means of a genome-wide analysis, an 11-miRNA expression signature that may serve as an underlying prognostic indicator for those patients suffering from STAD has been identified and described here.

Effect of miR‑145 on gastric cancer cells

Gastric cancer is one of the most common malignant tumors in the world. Due to the lack of early diagnosis and effective treatment, the outcome of treatment and prognosis is poor. MicroRNA-145 (miR-145) is downregulated in various cancer types. In the present study, miR-145 expression was detected by reverse transcription-quantitative polymerase chain reaction in gastric cancer cell lines and normal gastric epithelial cells. The function of miR-145 in the gastric cancer cell line SGC-7901 was investigated. The present results demonstrated that the expression of miR-145 was downregulated in gastric cancer cells. Further analysis identified that upregulation of miR-145 significantly suppressed SGC-7901 cell proliferation, increased cellular apoptosis and blocked the cell cycle in the G₁ phase. Additionally, overexpression of miR-145 reduced SGC-7901 cell invasion and metastasis in vitro. Western blot analysis demonstrated that overexpression of miR-145 downregulated Myc proto-oncogene protein, phosphoinositide 3-kinase/protein kinase B and matrix metalloproteinase 2/9, and upregulated p21 in SGC-7901 cells. The present results revealed potential signaling pathways that miR-145 may use to regulate gastric cancer cell proliferation, apoptosis and metastasis. Collectively, the present results suggest that miR-145 is a tumor suppressor for gastric cancer and it may be a potential therapeutic target for gastric cancer treatment.

MicroRNAs 145 and 148a Are Upregulated During Congenital Zika Virus Infection

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) member of the Flaviviridae family, which has been associated with the development of the congenital Zika syndrome (CZS). RNA viruses, such as flaviviruses, have been reported to exert a profound impact on host microRNAs (miRNAs). Cellular miRNAs modulated by ZIKV may help identify cellular pathways of relevance to pathogenesis. Here, we screened 754 human cellular miRNAs modulated by ZIKV infection (Brazilian PE strain) in a neuroblastoma cell line. Seven miRNAs (miR-99a*, miR-126*, miR-190b, miR-361-3p, miR-522-3p, miR-299-5p, and miR-1267) were downregulated during ZIKV infection, while miR-145 was upregulated. Furthermore, 11 miRNAs were exclusively expressed in ZIKV-infected (miR-148a, miR-342-5p, miR-598, and miR-708-3p) or mock cells (miR-208, miR-329, miR-432-5p, miR-488, miR-518b, miR-520g, and miR-767-5p). Furthermore, in silico analysis indicated that some central nervous system, cellular migration, and adhesion function-related biological processes were overrepresented in the list of target genes of the miRNAs regulated in ZIKV-infected cells, especially for miR-145 and miR-148a. The induction of miR-145 and miR-148a was confirmed in postmortem brain samples from stillborn with severe CZS. Finally, we determined the expression regulation of microcephaly related genes through RNA interference pathway caused by ZIKV directly on neuron cells.

Non-target Genes Regulate miRNAs-Mediated Migration Steering of Colorectal Carcinoma

MicroRNAs (miRNAs) trigger a two-layer regulatory network directly or through transcription factors and their co-regulators. Unlike miR-375, the role of miR-145 and miR-224 in inhibiting or driving cancer cell migration is controversial. This study is a step towards addressing the potential of miR-375, miR-145 and miR-224 expression modulation to inhibit colorectal carcinoma (CRC) cells migration in vitro through regulation of non-target genes VEGFA, TGFβ1, IGF1, CD105 and CD44. Transwell migration assay results revealed a significant subdue of migration ability of cells transfected with miR-375 and miR-145 mimics and miR-224 inhibitor. Real time PCR data showed that expression of VEGFA, TGFβ1, IGF1, CD105 and CD44 was downregulated as a consequence of exogenous re-expression of miR-375 and inhibition of miR-224. On the other hand, ectopic expression of miR-145 did not affect VEGFA, TGFβ1 and CD44 expression, while it elevated CD105 and suppressed IGF1 expression. MAP4K4, a predicted target of miR-145, was validated as a target that could play a role in miR-145-mediated regulation of migration. At mRNA level, no change was observed in expression of MAP4K4 in cells with restored expression of miR-145, while western blotting analysis revealed a 25% reduction of protein level. By applying luciferase reporter assay, a significant decrease in luciferase activity was observed, supporting that miR-145 directly target 3' UTR of MAP4K4. The study highlighted the involvement of non-target genes VEGFA, TGFβ1, IGF1, CD105 and CD44 in mediating anti- and pro-migratory effect of miR-375 and miR-224, respectively, and validated MAP4K4 as a direct target of anti-migratory miR-145.

Genome-wide identification of a novel miRNA-based signature to predict recurrence in patients with gastric cancer

The current tumor node metastasis (TNM) staging system is inadequate for identifying high-risk gastric cancer (GC) patients. Using a systematic and comprehensive-biomarker discovery and validation approach, we attempted to build a microRNA (miRNA)-recurrence classifier (MRC) to improve the prognostic prediction of GC. We identified 312 differentially expressed miRNAs in 446 GC tissues compared to 45 normal controls by analyzing high-throughput data from The Cancer Genome Atlas (TCGA). Using a Cox regression model, we developed an 11-miRNA signature that could successfully discriminate high-risk patients in the training set (n = 372; P < 0.0001). Quantitative real-time polymerase chain reaction-based validation in an independent clinical cohort (n = 88) of formalin-fixed paraffin-embedded clinical GC samples showed that MRC-derived high-risk patients succumb to significantly poor recurrence-free survival in GC patients (P < 0.0001). Cox and stratification analysis indicated that the prognostic value of this signature was independent of clinicopathological risk factors. Time-dependent receiver operating characteristic (ROC) analysis revealed that the area under the curve of this signature was significantly larger than that of TNM stage in the TCGA (0.733 vs. 0.589 at 3 years, P = 0.004; 0.802 vs. 0.635 at 5 years, P = 0.005) and validation cohort (0.835 vs. 0.689 at 3 years, P = 0.003). A nomogram was constructed for clinical use, which integrated both MRC and clinical-related variables (depth of invasion, lymph node status and distance metastasis) and did well in the calibration plots. In conclusion, this novel miRNA-based signature is superior to currently used clinicopathological features for identifying high-risk GC patients. It can be readily translated into clinical practice with formalin-fixed paraffin-embedded specimens for specific decision-making applications.

Tumor necrosis factor-alpha suppresses the invasion of HTR-8/SVneo trophoblast cells through microRNA-145-5p-mediated downregulation of Cyr61

Deficiency in trophoblast invasion is causally linked to the pathogenesis of preeclampsia. Tumor necrosis factor-alpha (TNF-α) shows the ability to suppress the invasiveness of trophoblasts, while cysteine-rich 61 (Cyr61) exerts an opposite function in trophoblast invasion. This study was designed to check the hypothesis that cysteine-rich 61 (Cyr61) may be involved in the anti-invasive activity of TNF-α in trophoblasts. To this end, we examined the effect of TNF-α treatment on Cyr61 expression in HTR-8/SVneo trophoblast cells and investigated the mechanism for the regulation of Cyr61 by TNF-α. Gain-of-function experiments were performed to clarify the role of Cyr61 in TNF-α-dependent suppression of trophoblast invasion. It was found that TNF-α at 1 and 10 ng/mL reduced Cyr61 protein levels by 30 and 80%, respectively, in HTR-8/SVneo cells, but did not affect the mRNA expression of Cyr61. Mechanistically, microRNA (miR)-145-5p was stimulated by TNF-α and negatively regulated the expression of Cyr61 via interaction with its 3'-untranslated region. Functionally, overexpression of miR-145-5p significantly impaired the migration and invasion of HTR-8/SVneo cells. Depletion of miR-145-5p rescued HTR-8/SVneo cells from TNF-α-mediated invasion suppression, which coincided with prevention of Cyr61 downregulation by TNF-α. In addition, overexpression of Cyr61 partially restored the invasion of HTR8/SVneo cells co-transfected with miR-145-5p mimic or exposed to TNF-α. Taken together, miR-145-5p-mediated downregulation of Cyr61 is required for the anti-invasive effect of TNF-α on trophoblasts.

Beta catenin is regulated by its subcellular distribution and mutant huntingtin status in Huntington's disease cell STHdhQ111/HdhQ111

Dysregulation of gene expression at RNA and protein level is a hallmark of Huntington's disease (HD). Altered levels of microRNAs and beta catenin in HD were studied earlier; however, any direct involvement of full length, basally-expressing mutant huntingtin (Htt) remained to be elusive. Here we reported that the gain-of-function mutation of full-length basally-expressing Htt in HD cell Q111 (STHdhQ111/HdhQ111) upregulated microRNA-214 and decreased beta catenin & its transcriptional activity in an aggregate-independent manner. The result was quite opposite of the function of aggregate-forming mutant Htt fragment 83Q-DsRed. Here, we also reported an elevated level of beta catenin phosphorylation in Q111 cell compared to Q7 cell (SThdhQ7/HdhQ7). We showed that in Q111 cell (compared to Q7), beta catenin was more localized in the cytosol than that of the plasma membrane. This is significant as Gsk3beta phosphorylates beta catenin in the cytosol. Hence, for the first time, our study identified beta catenin localization and mutant Htt status as two key factors of beta catenin regulation in HD.

MicroRNA-153 functions as a tumor suppressor in gastric cancer via targeting Kruppel-like factor 5

Various microRNAs (miRs) have been demonstrated to serve important roles in gastric cancer (GC). miR-153 in particular has been reported to serve a suppressive role in GC; however, the underlying mechanism remains unclear. In the present study Reverse transcription-quantitative polymerase chain reaction and western blot analysis were used to examine the mRNA and protein expression of Kruppel-like factor 5. An MTT, wound healing and transwell assay were used to study cell proliferation, migration and invasion, respectively. In the present study, quantitative polymerase chain reaction data indicated that miR-153 was significantly downregulated in GC tissues compared with the adjacent non-tumor tissues. In addition, the reduced expression of miR-153 was significantly associated with GC aggressiveness and poor prognosis of patients. The expression of miR-153 was also reduced in GC cell lines, including KATO III, NCI-N87, SNU-16 and SNU-5, when compared with normal gastric epithelial GES-1 cells. Overexpression of miR-153 in the GC SNU-5 cells by miR-153 mimic transfection significantly inhibited the cell proliferation, migration and invasion. Furthermore, KLF5 was identified as a target gene of miR-153 in SNU-5 cells by bioinformatics prediction. It was observed that KLF5 was significantly upregulated in GC tissues and cell lines, and its expression was negatively regulated by miR-153 in SNU-5 cells. Overexpression of KLF5 impaired the suppressive effects of miR-153 on the proliferation, migration and invasion of SNU-5 cells. In conclusion, the present study demonstrated that miR-153 serves a tumor suppressive role in GC, at least partly, through directly targeting KLF5, thus highlighting the clinical significance of miR-153 in GC.

microRNA‑145 modulates migration and invasion of bladder cancer cells by targeting N‑cadherin

MicroRNA (miRNA)‑145 has been demonstrated to serve a role in several types of tumors, however, the potential molecular mechanism of action of miRNA‑145 in bladder cancer metastasis remains to be elucidated. This study aimed to investigate the potential modulation of miRNA‑145 in bladder carcinoma and elucidate the underlying molecular mechanism. The expression of miRNA‑145 in bladder adenocarcinoma tissues and bladder cancer cells was measured by reverse transcription‑quantitative polymerase chain reaction. miRNA‑145 mimics and inhibitor were transfected into bladder cancer (BC) cells to determine the role of miRNA‑145 on cell motility and invasion measured by wound healing and transwell assays. Luciferase assay was performed to confirm whether N‑cadherin was the direct target of miRNA‑145. Subsequently, expression of N‑cadherin and matrix metalloproteinase‑9 (MMP9) in BC cells were detected by western blot analysis. miRNA‑145 was significantly downregulated cells and tissues from patients with BC, compared with healthy controls. miRNA‑145 markedly inhibited the ability of BC cells to migrate and invade. Furthermore, N‑cadherin was identified as a target of miRNA‑145 in BC cells. MMP9, acting downstream of N‑cadherin, was downregulated in BC cells by miRNA‑145. In the present study, miRNA‑145 suppressed the migration and invasion of BC cells by regulating N‑cadherin. The results of the present study indicated that miRNA‑145 may function as a tumor suppressor and may have a potential to be a diagnostic and predictive biomarker, and a therapeutic target for treatment of BC.

Long non-coding RNA SNHG14 contributes to gastric cancer development through targeting miR-145/SOX9 axis

This study aimed to elucidate the roles of long non-coding RNA SNHG14 in gastric cancer development. LncRNA SNHG14 was markedly up-regulated in gastric cancer tissues and cells. Knockdown of SNHG14 significantly inhibited SGC-7901 cell viability, migration, invasion, and promoted cell apoptosis. In addition, miR-145 was negatively regulated by SNHG14 and the effects of SNHG14 knockdown on cell viability, apoptosis, migration, invasion, and the expression of apoptosis-related proteins and EMT-markers were reversed by inhibition of miR-145 at the same time. Furthermore, SOX9 was verified as a functional target of miR-145, and miR-145 regulated tumor malignant behaviors through regulating SOX9. Besides, knockdown of SNHG14 inhibited the expression of p-PI3 K, p-AKT, and p-mTOR and promoted PTEN expression, where miR-145 inhibition had opposite effects. Moreover, the activated PI3 K/AKT/mTOR pathway caused by miR-145 inhibition was counteracted after knockdown of SOX9. Our findings indicate that up-regulation of lncRNA SNHG14 may contribute to gastric cancer development via targeting miR-145/SOX9 axis and involving in PI3 K/AKT/mTOR pathway. SNHG14-miR-145/SOX9 axis may be a promising therapeutic strategy for gastric cancer treatment.

Expression of Reg IV and SOX9 and their correlation in human gastric cancer

Background

Reg IV is a member of the regenerating gene family and has been demonstrated to be overexpressed in gastric cancer. However, the functional mechanism of Reg IV in gastric cancer is still unclear.

Methods

Expression of Reg IV and SOX9 were investigated by immunohistochemistry (IHC) and real-time PCR, and the correlation between the expression of Reg IV and SOX9 was analyzed in gastric cancer tissues. Reg IV expression vectors and a siRNA of Reg IV and SOX9 were transfected into human gastric cancer cells and the protein and mRNA levels of Reg IV and SOX9 were investigated by western blot and real-time PCR. The invasion and migration ability of gastric cancer cells with overexpressed Reg IV and with gene silence of Reg IV and SOX9 were examined by transwell chambers and wound healing assay.

Results

The Reg IV and SOX9 protein expression levels were both significantly higher in gastric cancer tissues compared with adjacent tissues (p = 0.022, p = 0.003). Reg IV protein expression significantly correlated with tumor invasion depth (p <  0.001), but had no significant correlations with age, clinical stage or lymph node metastasis. SOX9 protein expression also had no significant correlations with age, clinical stage, tumor invasion depth or lymph node metastasis. Reg IV transcript expression demonstrated a significant correlation with invasion depth and lymph node metastasis (p = 0.005, p <  0.001) and no significant correlations with age, clinical stage, tumor tissue differentiation or tumor size. SOX9 transcript expression demonstrated a significant correlation with invasion depth and tumor tissue differentiation (p = 0.044, p = 0.007) and no significant correlations with age, clinical stage or tumor size. The Reg IV expression showed a positive correlation with the SOX9 expression (p <  0.000, p = 0.008). Overexpression of Reg IV could upregulate SOX9 expression and promote invasiveness and migration of tumor cells, and silencing of Reg IV could downregulate SOX9 and inhibit invasiveness and migration of tumor cells in MKN-45 and AGS cells. On the other hand, silencing of SOX9 could upregulate Reg IV protein expression.

Conclusions

Our study demonstrated that Reg IV positively regulates the expression of SOX9 and is involved in tumor cell invasion and migration in gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4285-x) contains supplementary material, which is available to authorized users.

MicroRNA-222-3p associated with Helicobacter pylori targets HIPK2 to promote cell proliferation, invasion, and inhibits apoptosis in gastric cancer

Gastric cancer ranks as the second leading cause of malignancy-related death worldwide, and always diagnosed at advanced stage. MicroRNA-222-3p (miR-222-3p) is aberrantly upregulated in various malignant tumors including gastric cancer, but its role and underlying molecular mechanisms in gastric cancer remain largely unknown. Helicobacter pylori (H. pylori) infection acts as a trigger in the development of gastric cancer, and increasing evidence suggests that H. pylori affects microRNA expression. In this study, gastric cancer tissue samples were divided into H. pylori positive group (+) and negative group (-). QRT-PCR showed that miR-222-3p was significantly upregulated in H. pylori (+) group compared with H. pylori (-) group, and luciferase reporter assays identified homeodomain-interacting protein kinase 2 (HIPK2) as a novel target of miR-222-3p in gastric cancer. Immunohistochemistry revealed that HIPK2 levels were decreased in H. pylori (+) group compared with H. pylori (-). After that, functional experiments indicated that miR-222-3p overexpression promoted the proliferation and invasion, while inhibiting apoptosis of SGC7901 gastric cancer cells, but miR-222-3p knockdown exhibited the opposite effects. Also, HIPK2 knockdown induced similar effects as miR-222-3p overexpression in SGC7901 cells. Nude mouse experiments further suggested that HIPK2 overexpression signally attenuated the enhancing effect of miR-222-3p overexpression on cell proliferation, indicating that the effect of miR-222-3p on gastric cancer progression depends on HIPK2, at least in part. Overall, our results demonstrated that miR-222-3p/HIPK2 signal pathway regulated gastric cancer cell proliferation, apoptosis, and invasion, provided a novel therapeutic target for the treatment of gastric cancer infected by H. pylori.

Epithelial-mesenchymal transition in prostate cancer: an overview

Prostate cancer is a main urological disease associated with significant morbidity and mortality. Radical prostatectomy and radiotherapy are potentially curative for localized prostate cancer, while androgen deprivation therapy is the initial systemic therapy for metastatic prostate disease. However, despite temporary response, most patients relapse and evolve into castration resistant cancer.

Epithelial-mesenchymal transition (EMT) is a complex gradual process that occurs during embryonic development and/or tumor progression. During this process, cells lose their epithelial characteristics and acquire mesenchymal features. Increasing evidences indicate that EMT promotes prostate cancer metastatic progression and it is closely correlated with increased stemness and drug resistance.

In this review, we discuss the main molecular events that directly or indirectly govern the EMT program in prostate cancer, in order to better define the role and the mechanisms underlying this process in prostate cancer progression and therapeutic resistance.

miR-145 Antagonizes SNAI1-Mediated Stemness and Radiation Resistance in Colorectal Cancer

Epithelial-to-mesenchymal transition (EMT) has been closely linked with therapy resistance and cancer stem cells (CSCs). However, EMT pathways have proven challenging to therapeutically target. MicroRNA 145 (miR-145) targets multiple stem cell transcription factors and its expression is inversely correlated with EMT. Therefore, we hypothesized that miR-145 represents a therapeutic target to reverse snail family transcriptional repressor 1 (SNAI1)-mediated stemness and radiation resistance (RT). Stable expression of SNAI1 in DLD1 and HCT116 cells (DLD1-SNAI1; HCT116-SNAI1) increased expression of Nanog and decreased miR-145 expression compared to control cells. Using a miR-145 luciferase reporter assay, we determined that ectopic SNAI1 expression significantly repressed the miR-145 promoter. DLD1-SNAI1 and HCT116-SNAI1 cells demonstrated decreased RT sensitivity and, conversely, miR-145 replacement significantly enhanced RT sensitivity. Of the five parental colon cancer cell lines, SW620 cells demonstrated relatively high endogenous SNAI1 and low miR-145 levels. In the SW620 cells, miR-145 replacement decreased CSC-related transcription factor expression, spheroid formation, and radiation resistance. In rectal cancer patient-derived xenografts, CSC identified by EpCAM+/aldehyde dehydrogenase (ALDH)+ demonstrated high expression of SNAI1, c-Myc, and Nanog compared with non-CSCs (EpCAM+/ALDH-). Conversely, patient-derived CSCs demonstrated low miR-145 expression levels relative to non-CSCs. These results suggest that the SNAI1:miR-145 pathway represents a novel therapeutic target in colorectal cancer to overcome RT resistance.

miR-145 suppresses the proliferation, invasion and migration of NSCLC cells by regulating the BAX/BCL-2 ratio and the caspase-3 cascade

Although microRNA (miR)-145 has been identified to be a tumor suppressor in various types of tumor, it promotes the progression of non-small cell lung cancer (NSCLC). However, the precise underlying molecular mechanism of its action remains unclear. The present study investigated the effects of miR-145 on the proliferation, invasion, metastasis and apoptosis of the NSCLC A549 cell line and the underlying molecular mechanism of its action. In vitro cell proliferation, invasion, migration and apoptosis assays were employed, and the expression levels of matrix metalloproteinase (MMP)-2, MMP-9, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3and poly(ADP-ribose) polymerase (PARP) were evaluated by western blot analysis. The results demonstrated that ectopic expression of miR-145 inhibited the proliferation, invasion and migration of A549 cells, but promoted the apoptosis of A549 cells. Western blot analysis indicated that increased miR-145 levels led to a marked decrease in the expression of MMP-2, MMP-9 and Bcl-2. Upregulation of miR-145 expression increased the expression of Bax, thus increasing the Bax/Bcl-2 ratio. Additionally, the results indicated that miR-145 over expression promoted the cleavage of caspase-3 and PARP. Taken together, these results indicated that miR-145 suppresses the proliferative, invasive and migratory ability of A549 cells. Additionally, miR-145 upregulation induced apoptosis of A549 cells possibly by decreasing MMP-2 and MMP-9 expression, the Bax/Bcl-2 ratio and the activity of the caspase-3 cascade.

Epithelial Mesenchymal Transition in Embryonic Development, Tissue Repair and Cancer: A Comprehensive Overview

The epithelial mesenchymal transition (EMT) plays a central role in both normal physiological events (e.g., embryonic development) and abnormal pathological events (e.g., tumor formation and metastasis). The processes that occur in embryonic development are often reactivated under pathological conditions such as oncogenesis. Therefore, defining the regulatory networks (both gene and protein levels) involved in the EMT during embryonic development will be fundamental in understanding the regulatory networks involved in tumor development, as well as metastasis. There are many molecules, factors, mediators and signaling pathways that are involved in the EMT process. Although the EMT is a very old topic with numerous publications, recent new technologies and discoveries give this research area some new perspective and direction. It is now clear that these important processes are controlled by a network of transcriptional and translational regulators in addition to post-transcriptional and post-translational modifications that amplify the initial signals. In this review article, we will discuss some key concepts, historical findings, as well as some recent progresses in the EMT research field.

Methylation-induced downregulation and tumor suppressive role of microRNA-29b in gastric cancer through targeting LASP1

MicroRNAs (miRs) have been demonstrated to play promoting or tumor suppressive roles in various human cancers, but the regulatory mechanism of miR-29b underlying gastric cancer development and progression still remains largely unclear. In the present study, we found that miR-29b was significantly downregulated in gastric cancer tissues and cell lines. Low expression of miR-29b was significantly associated with DNA methylation, and treatment with DNA methyltransferase inhibitor 5-Aza-20-deoxycytidine upregulated miR-29b in gastric cancer cells. In addition, both reduced miR-29b expression and miR-29b methylation were associated with disease progression and poor prognosis in gastric cancer. Restoration of miR-29b caused a reduction in gastric cancer cell proliferation, migration, and invasion, and inhibited tumor growth in vivo. LASP1 was then identified as a target gene of miR-29b in gastric cancer cells. Moreover, upregulation of LASP1 was significantly associated with gastric cancer progression and poor prognosis. Knockdown of LASP1 also suppressed the proliferation, migration, and invasion of gastric cancer cells. Moreover, overexpression of LASP1 impaired the suppressive effects of miR-29b on the malignant phenotypes of gastric cancer cells, suggesting that miR-29b may inhibit gastric cancer growth and metastasis via targeting LASP1. According to these data, miR-29b may be used as a potential therapeutic candidate for gastric cancer.