MicroRNA-1 (miR-1) inhibits gastric cancer cell proliferation and migration by targeting MET

Non-coding RNAs as potential therapeutic targets for receptor tyrosine kinase signaling in solid tumors: current status and future directions

This review article presents an in-depth analysis of the current state of research on receptor tyrosine kinase regulatory non-coding RNAs (RTK-RNAs) in solid tumors. RTK-RNAs belong to a class of non-coding RNAs (nc-RNAs) responsible for regulating the expression and activity of receptor tyrosine kinases (RTKs), which play a critical role in cancer development and progression. The article explores the molecular mechanisms through which RTK-RNAs modulate RTK signaling pathways and highlights recent advancements in the field. This include the identification of potential new RTK-RNAs and development of therapeutic strategies targeting RTK-RNAs. While the review discusses promising results from a variety of studies, encompassing in vitro, in vivo, and clinical investigations, it is important to acknowledge the challenges and limitations associated with targeting RTK-RNAs for therapeutic applications. Further studies involving various cancer cell lines, animal models, and ultimately, patients are necessary to validate the efficacy of targeting RTK-RNAs. The specificity of ncRNAs in targeting cellular pathways grants them tremendous potential, but careful consideration is required to minimize off-target effects, the article additionally discusses the potential clinical applications of RTK-RNAs as biomarkers for cancer diagnosis, prognosis, and treatment. In essence, by providing a comprehensive overview of the current understanding of RTK-RNAs in solid tumors, this review emphasizes their potential as therapeutic targets for cancer while acknowledging the associated challenges and limitations.

Signaling pathways and therapeutic interventions in gastric cancer

Gastric cancer (GC) ranks fifth in global cancer diagnosis and fourth in cancer-related death. Despite tremendous progress in diagnosis and therapeutic strategies and significant improvements in patient survival, the low malignancy stage is relatively asymptomatic and many GC cases are diagnosed at advanced stages, which leads to unsatisfactory prognosis and high recurrence rates. With the recent advances in genome analysis, biomarkers have been identified that have clinical importance for GC diagnosis, treatment, and prognosis. Modern molecular classifications have uncovered the vital roles that signaling pathways, including EGFR/HER2, p53, PI3K, immune checkpoint pathways, and cell adhesion signaling molecules, play in GC tumorigenesis, progression, metastasis, and therapeutic responsiveness. These biomarkers and molecular classifications open the way for more precise diagnoses and treatments for GC patients. Nevertheless, the relative significance, temporal activation, interaction with GC risk factors, and crosstalk between these signaling pathways in GC are not well understood. Here, we review the regulatory roles of signaling pathways in GC potential biomarkers, and therapeutic targets with an emphasis on recent discoveries. Current therapies, including signaling-based and immunotherapies exploited in the past decade, and the development of treatment for GC, particularly the challenges in developing precision medications, are discussed. These advances provide a direction for the integration of clinical, molecular, and genomic profiles to improve GC diagnosis and treatments.

LILRB4 promotes tumor metastasis by regulating MDSCs and inhibiting miR-1 family miRNAs

Myeloid-derived suppressor cells (MDSCs) are a population of immune suppressive cells that are involved in tumor-associated immunosuppression, and dominate tumor progression and metastasis. In this study, we report that the leukocyte immunoglobulin-like receptor subfamily B member 4 (LILRB4, murine ortholog gp49B) orchestrates the polarization of MDSCs to exhibit pro-tumor phenotypes. We found that gp49B deficiency inhibited tumor metastases of cancer cells, and reduced tumor-infiltration of monocytic MDSCs (M-MDSCs) in tumor-bearing mice. Gp49B^−/− MDSCs inhibited pro-tumor immune responses, such as activation of Treg cells, promotion of cancer cell migration, and stimulation of tumor angiogenesis. Treatment of wild-type tumor-bearing mice with gp49B^−/− M-MDSCs reduced cancer metastasis. Furthermore, gp49B knockout affected plasma exosome composition in terms of increased miR-1 family microRNAs (miRNAs) expression, which correlates with the upregulation of gp49B^−/− MDSC-derived anti-tumor miRNAs. Collectively, our findings reveal that LILRB4/gp49B promotes MDSC-mediated tumor metastasis by regulating the M2-polarization of MDSCs and suppressing the secretion of miR-1 family miRNAs, which facilitate tumor migration and invasion.

Abbreviations

CTLA-4: cytotoxic T-lymphocyte-associated protein-4; FBS: fetal bovine serum; G-MDSCs: granulocytic-MDSCs; GP49B: glycoprotein 49B; HE: hematoxylin-eosin; ICI: immune checkpoint inhibitor; ITIM: immunoreceptor tyrosine-based inhibition motif; LILRB4: leukocyte immunoglobulin-like receptor B4; M-CSF: macrophage colony stimulating factor; MDSC: myeloid-derived suppressor cell; M-MDSC: monocytic MDSC; MMP-9: metallopeptidase-9; mAb: monoclonal antibody; PBS: phosphate-buffered saline; PCR: polymerase chain reaction; PD-1: programmed death-1; PD-L1: programmed death ligand-1; PMN-MDSC: polymorphonuclear-MDSC; qRT-PCR: quantitative reverse transcription PCR; TAM: tumor associated macrophage; TME: tumor microenvironment; TMM: trimmed mean of M value; VEGFA: vascular endothelial growth factor A

MiR-1-3p targets CENPF to repress tumor-relevant functions of gastric cancer cells

Here we noted significantly downregulated miR-1-3p in gastric cancer (GC) tissue compared with adjacent normal tissue through qRT-PCR. Lowly expressed miR-1-3p correlated GC progression. Overexpressing miR-1-3p could restrain tumor-relevant cell behaviors in GC, while miR-1-3p inhibitor treatment triggered the opposite results. Moreover, dual-luciferase reporter gene detection identified specific binding sites of miR-1-3p in CENPF 3’untranslated region. Upregulating miR-1-3p constrained cell progression of GC via CENPF downregulation. Western blot, qRT-PCR and dual-luciferase detections manifested that miR-1-3p negatively mediated CENPF expression in GC cells. Thus, we demonstrated that miR-1-3p negatively mediated CENPF to hamper GC progression. CENPF may be an underlying target for GC therapy.

Pan-cancer analysis of biological events on cell cycle instability in gastrointestinal cancers with integrative scoring method

Omics data integration plays an essential role in manifesting hidden cancer insights. To detect the main combinatorial/parallel impact of cancer events, integrative approaches in pan-cancer studies must be used. Here, we assessed gastrointestinal (GI) cancers from several perspectives of genomics, transcriptomics, epigenomics, and also combinatorial impacts using a novel integrative approach to score genes. Next, scores were diffused on a signaling network and extracted subnetworks. We also implemented our new scoring method to compare upper-/lower-GI cancers, investigate the regulatory mechanisms of lncRNAs, and detect amplifications/deletions between GI and non-GI cancers. The integrative subnetwork indicated the interplay among essential protein families in the cell cycle. The copy-number-variation-related subnetwork revealed minor cell cycle and immune effects, whereas the methylation-related subnetwork revealed significant immune effects. The top-score lncRNAs indicated a distinct regulatory pattern for lower-/upper-, and accessory-GI categories. In summary, cell cycle dysfunction might be largely the consequence of combinatorial abnormalities.

Investigating Helicobacter pylori-related pyloric hypomotility: functional, histological, and molecular alterations

Multiple theories have been proposed describing the pathogenic mechanisms of Helicobacter pylori (H. pylori)-associated gastric motility disorders. We assessed ex vivo pyloric activity in H. pylori-infected rats, and tried to explore the associated ghrelin hormone alteration and pyloric fibrogenesis. In addition, miR-1 was assessed in pyloric tissue samples, being recently accused of having a role in smooth muscle dysfunction. Ninety adult male Wistar albino rats were assigned into nine groups: 1) control group, 2) sterile broth (vehicle group), 3) amoxicillin control, 4) omeperazole control, 5) clarithromycin control, 6) triple therapy control, 7) H. pylori- group, 8) H. pylori-clarithromycin group, and 9) H. pylori-triple therapy group. Urease enzyme activity was applied as an indicator of H. pylori infection. Ex vivo pyloric contractility was evaluated. Serum ghrelin was assessed, and histological tissue evaluation was performed. Besides, pyloric muscle miR-1 expression was measured. The immunological epithelial to mesenchymal transition (EMT) markers; transforming growth factor β (TGFβ), α-smooth muscle actin (α-SMA), and E-cadherin-3 were also evaluated. By H. pylori infection, a significant (P < 0.001) reduced pyloric contractility index was recorded. The miR-1 expression was decreased (P < 0.001) in the H. pylori-infected group, associated with reduced serum ghrelin, elevated TGFβ, and α-SMA levels and reduced E-cadherin levels. Decreased miR-1 and disturbed molecular pattern were improved by treatment. In conclusion, H. pylori infection was associated with reduced miR-1, epithelial to mesenchymal transition, and pyloric hypomotility. The miR-1 may be a target for further studies to assess its possible involvement in H. pylori-associated pyloric dysfunction, which might help in the management of human H. pylori manifestations and complications.NEW & NOTEWORTHY This work is investigating functional, histopathological, and molecular changes underlying Helicobacter pylori hypomotility and is correlating these with miR-1, whose disturbance is supposed to be involved in smooth muscle dysfunction and cell proliferation according to literature. Epithelial to mesenchymal transition and reduced ghrelin hormone may contribute to H. pylori infection-associated hypomotility. H. pylori infection was associated with reduced pyloric miR-1 expression. Targeting miR-1 could be valuable in the clinical management of pyloric hypofunction.

Synthetic Evaluation of MicroRNA-1-3p Expression in Head and Neck Squamous Cell Carcinoma Based on Microarray Chips and MicroRNA Sequencing

Background

MicroRNA-1-3p (miR-1-3p) exerts significant regulation in various tumor cells, but its molecular mechanisms in head and neck squamous cell carcinoma (HNSCC) are still ill defined. This study is aimed at detecting the expression of miR-1-3p in HNSCC and at determining its significant regulatory pathways.

Methods

Data were obtained from the Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Oncomine, ArrayExpress, Sequence Read Archive (SRA) databases, and additional literature. Expression values of miR-1-3p in HNSCC were analyzed comprehensively. The R language software was employed to screen differentially expressed genes, and bioinformatics assessment was performed. One sequence dataset (HNSCC: n = 484; noncancer: n = 44) and 18 chip datasets (HNSCC: n = 656; noncancer: n = 199) were obtained.

Results

The expression of miR-1-3p in HNSCC was visibly decreased in compare with noncancerous tissues. There were distinct differences in tumor state (P = 0.0417), pathological stage (P = 0.0058), and T stage (P = 0.0044). Comprehensive analysis of sequence and chip data also indicated that miR-1-3p was lowly expressed in HNSCC. The diagnostic performance of miR-1-3p in HNSCC is reflected in the sensitivity and specificity of the collection, etc. Bioinformatics analysis showed the possible biological process, cellular component, molecular function, and KEGG pathways of miR-1-3p in HNSCC. And ITGB4 was a possible target of miR-1-3p.

Conclusions

miR-1-3p's low expression may facilitate tumorigenesis and evolution in HNSCC through signaling pathways. ITGB4 may be a key gene in targeting pathways but still needs verification through in vitro experiments.

The Level of Mesenchymal-Epithelial Transition Autophosphorylation is Correlated with Esophageal Squamous Cell Carcinoma Migration

Background

The MET receptor is a critical member of cancer-associated receptor tyrosine kinases and plays an important role in different biological activities, including differentiation, migration, and cell proliferation.

Methods

In this study, novel MET inhibitors were introduced and applied on esophageal squamous carcinoma cell line KYSE-30, and the level of proliferation and migration, as well as the activated form of MET receptor protein were assessed in the examined cells. The human KYSE-30 cell line was cultured according to ATCC recommendations. The mRNA level of the MET gene was measured in the examined cell line using the quantitative RT-PCR assay. Cytotoxicity evaluation test was performed at different concentrations of heterocyclic anti-MET compounds (i.e. D1, D2, D5, D6, D7, and D8). Finally, the capability of these compounds in MET receptor inhibition was evaluated using the migration assay and Western blot. All experiments were performed in triplicate and repeated three times with similar results.

Results

Cell growth and proliferation were significantly inhibited (p ≤ 0.05) by all the above-mentioned compounds. Moreover, the majority of compounds significantly prevented the cell migration (p ≤ 0.05) and inhibited MET autophosphorylation. Interestingly, the level of phosphorylated MET was significantly correlated with KYSE-30 cell migration.

Conclusion

The obtained data introduced and confirmed the biological activities of the mentioned novel compounds in KYSE-30 cells and proposed that the therapeutic inhibition of MET with these compounds may be a powerful approach for inhibiting cancer cell migration and proliferation although some structural optimizations are needed to improve their inhibitory functions.

MET and FASN as Prognostic Biomarkers of Triple Negative Breast Cancer: A Systematic Evidence Landscape of Clinical Study

Background

To know the expression of Mesenchymal–Epithelial Transition factor (MET) and Fatty Acid Synthase (FASN) in Triple Negative Breast Cancer (TNBC) patients, as well as its relationship with clinical pathological characteristic and prognosis.

Methods

we used immunohistochemistry staining to detect the expression of MET and FASN for those 218 TNBC patients, and analyze their relationship with the clinical pathological characteristic and prognosis.

Results

130 and 65 out of 218 TNBC patients were positive for MET in the cancer and adjacent tissues respectively. 142 and 30 out of 218 TNBC patients were positive for FASN in the cancer and adjacent tissues respectively. Positive expression of MET and FASN were significantly correlated with lymph node metastasis, pathological TNM, and pathological Stage. In addition, the positive expression of MET and FASN were correlated with recurrence and metastasis. The combined use of MET and FASN can better predict the survival condition.

Conclusions

Our results indicated that MET and FASN showed good predictive ability for TNBC. Combined use of MET and FASN were recommended in order to make a more accurate prognosis for TNBC.

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.

[microRNA-1 gene delivery mediated by exosomes suppresses CAL-27 cell proliferation]

OBJECTIVES

This study aims to construct endogenous exosomes abundantly loaded with miR-1 and investigate the role of exosome-mediated microRNA-1 (miR-1) delivery on CAL-27 cell proliferation.

METHODS

Exosomes secreted by miR-1-overexpressing HEK293 cells (miR1-EXO) were purified via ultracentrifugation and subjected to transmission electron microscopy, nanoparticle analysis, Western blot analysis, and quantitative polymerase chain reaction (qPCR). CAL-27 cells were cocultured with exosomes secreted by HEK293 cells (CON-EXO) and miR1-EXO and equivalent phosphate buffer saline. The intracellular transport of exosomes was measured by using immunofluorescence, the expression of miR-1 and its target gene MET were investigated via qPCR, CAL-27 cell proliferation was measured through MTT assay, and cell cycle state was determined by applying flow cytometry.

RESULTS

Electron microscopy revealed that miR1-EXO and CON-EXO were spherical or cup-shaped with an average diameter of approximately 110 nm. The well-known exosome markers CD9, Tsg101, and Alix were enriched. The expression of miR-1 in miR1-EXO was higher than that in CON-EXO (285.80±14.33 vs 1.00±0.06, P<0.000 1). After coculture with CAL-27 cells, miR1-EXO was internalized and unloaded miR-1 into CAL-27 cells. After coculture with miR1-EXO, the expression of miR-1 in CAL-27 cells was upregulated, whereas that of MET, the target gene of miR-1, was suppressed and the proliferation of CAL-27 cells was inhibited significantly. Normal oral keratinocyte cell proliferation was negligibly affected after coculture with miR1-EXO.

CONCLUSIONS

Exosomes secreted from miR1-EXO cells could load abundant miR-1. Exosomal miR-1 delivered into CAL-27 cells by using miR1-EXO suppressed the expression of MET mRNA and inhibited cell proliferation.

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.

Molecular micromanagement: DNA nanotechnology establishes spatio-temporal control for precision medicine

Current advances in DNA nanotechnology pinpoint exciting perspectives for the design of customized, patient-specific treatments. This advance is made possible by the exceptionally high precision and specificity that are typical for DNA base pairing on the one hand and our growing ability to harness those features in synthetic, DNA-based constructs on the other hand. Modern medicine may soon benefit from recent developments in this field, especially regarding the targeted delivery of drugs and the rational interference of synthetic DNA strands with cellular oligonucleotides. In this Review, we summarize selected examples from the area of DNA nanotechnology, where the development of precisely controlled, advanced functional mechanisms was achieved. To demonstrate the high versatility of these rationally designed structures, we categorize the dynamic DNA-based materials suggested for precision medicine according to four fundamental tasks: "hold & release," "heal," "detect & measure," as well as "guide & direct." In all the biomedical applications we highlight, DNA strands not only constitute structural building blocks but allow for creating stimuli-responsive objects, serve as an active cargo, or act as molecular control/guidance tools. Moreover, we discuss several issues that need to be considered when DNA-based structures are designed for applications in the field of precision medicine. Even though the majority of DNA-based objects have not been used in clinical settings yet, recent progress regarding the stability, specificity, and control over the dynamic behavior of synthetic DNA structures has advanced greatly. Thus, medical applications of those nanoscopic objects should be feasible in the near future.

Effect of miR-184 on Proliferation and Apoptosis of Pancreatic Ductal Adenocarcinoma and Its Mechanism

Objective:

Previous studies have shown that abnormal expression of microRNA-184 leads to a variety of cancers, including pancreatic ductal adenocarcinoma, suggesting microRNA-184 as a new treatment target for pancreatic ductal adenocarcinoma. However, the molecular mechanism of microRNA-184 in pancreatic ductal adenocarcinoma remains unclear. It is important to investigate the effect and role of microRNA-184 in pancreatic ductal adenocarcinoma.

Methods:

The clinical and laboratory inspection data of 120 patients with pancreatic cancer admitted to the First Affiliated Hospital of Anhui Medical University were compared. MicroRNA-184 expression in tumor tissues and cells was evaluated using reverse transcription polymerase chain reaction. Flow cytometry and Annexin V/propidium iodide staining were performed to examine cell cycle and apoptosis. Western blotting analysis was conducted to measure the protein expression of p-PI3K, p-AKT, JNK1, C-Myc, C-Jun, caspase-9, and caspase-3.

Results:

MicroRNA-184 expression was low in patients with pancreatic ductal adenocarcinoma. Survival curve showed that patients with lower expression of microRNA-184 in tumor tissues had a worse prognosis and shorter survival time (P < .05), and the multivariate analysis identified that microRNA-184 was an independent prognostic indicator (P < .05). In vitro studies showed that microRNA-184 overexpression induced apoptosis and suppressed cell cycle transition from G1 to S and G2 phases in pancreatic ductal adenocarcinoma cells. Furthermore, molecular studies revealed that inhibition of microRNA-184 promoted the gene expression of p-PI3K, p-AKT, JNK1, C-Myc, and C-Jun compared with the control group. Overexpression of microRNA-184 led to significantly increased expression of caspase-9 and caspase-3 and significantly decreased expression of Bcl-2.

Conclusion:

This study suggests that microRNA-184 inhibits the proliferation and promotes the apoptosis of pancreatic ductal adenocarcinoma cells by downregulating the expression of C-Myc, C-Jun, and Bcl-2. Our verification of the role of microRNA-184 may provide a novel biomarker for the diagnosis, therapy, and prognosis of pancreatic ductal adenocarcinoma.

Downregulation of miR-1 in colorectal cancer promotes radioresistance and aggressive phenotypes

Background: Colorectal cancer (CRC) remains to be one of the most common malignancies worldwide. Various studies have demonstrated that microRNAs (miRs) play a critical role in regulating cancer progression and sensitivity to chemoradiotherapy. miR-1 was found to be aberrantly expressed in CRC. However, it has not been fully elucidated whether miR-1 regulated CRC cell radioresistance.

Methods: The expression of miR-1 was detected using quantitative real-time polymerase chain reaction in CRC tissues and cell lines. Colony survival and proliferation were determined using colony formation assay and MTT assay, respectively. Apoptosis and levels of related proteins, Bax and Bcl-2, were detected using flow cytometer assay and western blotting analysis. Migration and invasion were measured using wound healing assay and transwell invasion assay. The levels of invasion-associated proteins, E-cadherin, MMP2 and MMP9, were detected using western blotting analysis.

Results: miR-1 was found to be downregulated in CRC tissues and cell lines compared with adjacent normal tissues. In vitro, miR-1 overexpression significantly suppressed colony survival and proliferation, and induced cell apoptosis under irradiation, but no apoptosis was detected without irradiation. Furthermore, miR-1 mimics promoted the expression of Bax and E-cadherin and decreased the expression of Bcl-2, MMP2 and MMP9, and apparently impaired the invasion and migration of CRC cells in synergy with radiotherapy.

Conclusion: miR-1 enhanced the radiosensitivity of CRC cells by inducing cell apoptosis and the synergic inhibition of aggressive phenotypes, which may serve as a promising therapeutic target for CRC patients.

MicroRNAs and Long Non-coding RNAs in c-Met-Regulated Cancers

MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are components of many signaling pathways associated with tumor aggressiveness and cancer metastasis. Some lncRNAs are classified as competitive endogenous RNAs (ceRNAs) that bind to specific miRNAs to prevent interaction with target mRNAs. Studies have shown that the hepatocyte growth factor/mesenchymal-epithelial transition factor (HGF/c-Met) pathway is involved in physiological and pathological processes such as cell growth, angiogenesis, and embryogenesis. Overexpression of c-Met can lead to sustained activation of downstream signals, resulting in carcinogenesis, metastasis, and resistance to targeted therapies. In this review, we evaluated the effects of anti-oncogenic and oncogenic non-coding RNAs (ncRNAs) on c-Met, and the interactions among lncRNAs, miRNAs, and c-Met in cancer using clinical and tissue chromatin immunoprecipition (ChIP) analysis data. We summarized current knowledge of the mechanisms and effects of the lncRNAs/miR-34a/c-Met axis in various tumor types, and evaluated the potential therapeutic value of lncRNAs and/or miRNAs targeted to c-Met on drug-resistance. Furthermore, we discussed the functions of lncRNAs and miRNAs in c-Met-related carcinogenesis and potential therapeutic strategies.

MicroRNA Profile Identifies miR-6165 Could Suppress Gastric Cancer Migration and Invasion by Targeting STRN4

Background

Recent studies showed that aberrant expression of miRNAs causes tumor-suppressing or promoting effects in various cancers including gastric cancer (GC). Our previous studies showed that lots of miRNAs and mRNA expressed differentially in GC and normal tissues. However, the critical miRNAs and mRNA need to be clarified.

Materials and Methods

Microarray sequencing was used to profile the differential expression of miRNAs and mRNA in GC and normal tissues. Bioinformatics analysis and database prediction were used to search the critical miRNAs and mRNA. Real-time quantitative polymerase chain reaction (RT-qPCR), luciferase reporter assay, immunohistochemistry (IHC), wound healing assay and transwell assay were used to clarify the relationship between the target miRNAs and mRNA. Statistical analysis was used to seek their value of diagnosis and prognosis.

Results

We identified microRNA-6165 (miR-6165) as a novel cancer-related miRNA in GC through high-throughput microarray sequencing. By bioinformatics analysis and luciferase reporter assay, we found STRN4 was the target of miR-6165. Via a series of cell experiments, we determined that miR-6165 suppressed GC cells migration and invasion by targeting STRN4. Also, we discovered the potential diagnosis and prognosis value of miR-6165 and STRN4.

Conclusion

It was found that miR-6165 might suppress GC migration and invasion by targeting STRN4 in vitro, and the further research should focus more on the potential diagnosis and prognosis value of miR-6165 and STRN4 in gastric cancer patients.

Crosstalk Mechanisms Between HGF/c-Met Axis and ncRNAs in Malignancy

Several lines of evidence have confirmed the magnitude of crosstalk between HGF/c-Met axis (hepatocyte growth factor and its high-affinity receptor c-mesenchymal-epithelial transition factor) and non-coding RNAs (ncRNAs) in tumorigenesis. Through activating canonical or non-canonical signaling pathways, the HGF/c-Met axis mediates a range of oncogenic processes such as cell proliferation, invasion, apoptosis, and angiogenesis and is increasingly becoming a promising target for cancer therapy. Meanwhile, ncRNAs are a cluster of functional RNA molecules that perform their biological roles at the RNA level and are essential regulators of gene expression. The expression of ncRNAs is cell/tissue/tumor-specific, which makes them excellent candidates for cancer research. Many studies have revealed that ncRNAs play a crucial role in cancer initiation and progression by regulating different downstream genes or signal transduction pathways, including HGF/c-Met axis. In this review, we discuss the regulatory association between ncRNAs and the HGF/c-Met axis by providing a comprehensive understanding of their potential mechanisms and roles in cancer development. These findings could reveal their possible clinical applications as biomarkers for therapeutic interventions.

Characterization of ceRNA network to reveal potential prognostic biomarkers in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a particular subtype of breast malignant tumor with poorer prognosis than other molecular subtypes. Previous studies have demonstrated that some abnormal expression of non-coding RNAs including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) were closely related to tumor cell proliferation, apoptosis, invasion, migration and drug sensitivity. However, the role of non-coding RNAs in the pathogenesis of TNBC is still unclear. In order to characterize the molecular mechanism of non-coding RNAs in TNBC, we downloaded RNA data and miRNA data from the cancer genome atlas database. We successfully identified 686 message RNAs (mRNAs), 26 miRNAs and 50 lncRNAs as key molecules for high risk of TNBC. Then, we hypothesized that the lncRNA–miRNA–mRNA regulatory axis positively correlates with TNBC and constructed a competitive endogenous RNA (ceRNA) network of TNBC. Our series of analyses has shown that five molecules (TERT, TRIML2, PHBP4, mir-1-3p, mir-133a-3p) were significantly associated with the prognosis of TNBC, and there is a prognostic ceRNA sub-network between those molecules. We mapped the Kaplan–Meier curve of RNA on the sub-network and also suggested that the expression level of the selected RNA is related to the survival rate of breast cancer. Reverse transcription-quantitative polymerase chain reaction showed that the expression level of TRIML2 in TNBC cells was higher than normal. In general, our findings have implications for predicting metastasis, predicting prognosis and discovering new therapeutic targets for TNBC.

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.

Therapeutic microRNAs in human cancer

MicroRNAs (miRNAs) are RNA molecules at about 22 nucleotide in length that are non-coding, which regulate gene expression in the post-transcriptional level by performing degradation or blocks translation of the target mRNA. It is known that they play roles in mechanisms such as metabolic regulation, embryogenesis, organogenesis, differentiation and growth control by providing post-transcriptional regulation of gene expression. With these properties, miRNAs play important roles in the regulation of biological processes such as proliferation, differentiation, apoptosis, drug resistance mechanisms in eukaryotic cells. In addition, there are miRNAs that can be used for cancer therapy. Tumor cells and tumor microenvironment have different miRNA expression profiles. Some miRNAs are known to play a role in the onset and progression of the tumor. miRNAs with oncogenic or tumor suppressive activity specific to different cancer types are still being investigated. This review summarizes the role of miRNAs in tumorigenesis, therapeutic strategies in human cancer and current studies.

MiR-708-5p inhibits proliferation, migration and invasion of gastric cancer cells by targeting GAGE12I

AIM

To explore the effect of miR-708-5p on the proliferation, migration and invasion of gastric cancer (GC) cells and the possible mechanism involved.

METHODS

qRT-PCR was used to detect the expression of miR-708-5p in GC cell lines AGS and BGC-823. MTT, colony formation and Transwell chamber assays were performed to detect the effect of overexpression of miR-708-5p and silencing of GAGE12I on the proliferation, migration and invasion of AGS and BGC-823 cells. The double luciferase reporter gene experiment was performed to confirm the relationship between miR-708-5p and GAGE12I. Western blot analysis was used to detect the effect of miR-708-5p on the expression of GAGE12I. Target response assay was used to confirm the effect of GAGE12I on the inhibition of proliferation, migration and invasion of AGS and BGC-823 cells by miR-708-5p.

RESULTS

MiR-708-5p was downregulated in GC tissues and GC cell lines AGS and BGC-823. Upregulation of miR-708-5p and silencing of GAGE12I inhibited the proliferation, migration and invasion of AGS cells. GAGE12I was a target gene of miR-708-5p, and miR-708-5p negatively regulated GAGE12I expression. Overexpression of GAGE12I partly reversed the inhibitory effect of miR-708-5p on proliferation, migration and invasion of AGS and BGC-823 cells.

CONCLUSION

MiR-708-5p inhibits the proliferation, migration and invasion of GC cells by targeting GAGE12I.

HGF/c-MET: A Promising Therapeutic Target in the Digestive System Cancers

The HGF/c-MET pathway is active in the development of digestive system cancers, indicating that inhibition of HGF/c-MET signaling may have therapeutic potential. Various HGF/c-MET signaling inhibitors, mainly c-MET inhibitors, have been tested in clinical trials. The observed efficacy and adverse events of some c-MET inhibitors were not very suitable for treating digestive system cancers. The development of new HGF/c-MET inhibitors in preclinical studies may bring promising treatments and synergistic combination (traditional anticancer drugs and c-MET inhibitors) strategies provided anacceptable safety and tolerability. Insights into miRNA biology and miRNA therapeutics have made miRNAs attractive tools to inhibit HGF/c-MET signaling. Recent reports show that several microRNAs participate in inhibiting HGF/c-MET signaling networks through antagonizing c-MET or HGF in digestive system cancers, and the miRNAs-HGF/c-MET axis plays crucial and novel roles for cancer treatment. In the current review, we will discuss recent findings about inhibitors of HGF/c-MET signaling in treating digestive system cancers, and how miRNAs regulate digestive system cancers via mediating HGF/c-MET pathway.

The Clinical Significance of Changes in the Expression Levels of MicroRNA-1 and Inflammatory Factors in the Peripheral Blood of Children with Acute-Stage Asthma

This study assessed the changes and clinical significance of microRNA-1 (miR-1) and inflammatory factors in the peripheral blood of children with acute-stage asthma. 100 children with acute-stage asthma (study group) and 100 healthy children (control group) were enrolled. For all enrolled children, the peripheral blood levels of miR-1, interleukin-4 (IL-4), IL-5, IL-8, tumor necrosis factor-alpha (TNF-α), and interferon-γ (IFN-γ) were measured. The relative expression levels of miR-1 and IFN-γ in the peripheral blood of children in the study group were significantly lower than those in the control group, whereas expression levels of IL-4, IL-5, IL-8, and TNF-α were significantly higher. Moreover, these levels changed to a greater extent in patients with severe disease (P < 0.05). Further analyses showed that the miR-1 expression level positively correlated with IFN-γ and negatively correlated with IL-4, IL-5, IL-8, and TNF-α expression levels (P < 0.05). ROC curve analysis to identify diagnostic specificity and sensitivity showed that, for diagnosing exacerbation in asthma, the area under the curve (AUC) for miR-1 was the highest (AUC = 0.900, P < 0.05) of all tested markers; this held true for diagnosing severe asthma as well (AUC = 0.977, P < 0.05). Compared to healthy children, children with acute-stage asthma had a low miR-1 expression level and a Th1/Th2 imbalance in their peripheral blood. The changes were closely related, became more exaggerated with an increase in disease severity, and could be used as auxiliary variables for diagnosing asthma exacerbation and evaluating disease severity.

Expression level and potential target pathways of miR-1-3p in colorectal carcinoma based on 645 cases from 9 microarray datasets

For the purpose of demonstrating the clinical value and unraveling the molecular mechanisms of micro RNA (miR)-1-3p in colorectal carcinoma (CRC), the present study collected expression and diagnostic data from Gene Expression Omnibus (GEO), ArrayExpress and existing literature to conduct meta-analyses and diagnostic tests. Furthermore, the potential targets of miR-1-3p were attained from datasets that transfected miR-1-3p into CRC cells, online prediction databases and differentially expressed genes from The Cancer Genome Atlas and literature. Subsequently, bioinformatics analysis was conducted based on the aforementioned selected target genes. As a result, downregulation of miR-1-3p was observed. The combined standardized mean difference was −0.51 with 95% confidence interval (CI) of −0.68 to −0.33 using a fixed effect model, which demonstrated a significant downregulation of miR-1-3p in CRC. The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio diagnostic score and odds ratio were 0.74 (95%CI: 0.48, 0.90), 0.75 (95%CI: 0.35, 0.94), 2.94 (95%CI: 1.01, 8.55), 0.34 (95%CI: 0.19, 0.60), 2.15 (95%CI: 1.06, 3.23) and 8.57 (95%CI: 2.89, 25.36). The summarized receiver operating characteristic curve demonstrated that the area under the curve was 0.81. In bioinformatics analyses based on 30 promising targets, the most enriched terms in Gene Ontology were positive regulation of transcription from RNA polymerase II promoter, extracellular region and transcription factor binding. Kyoto Encyclopedia of Genes and Genomes pathway analysis highlighted the pathway termed cytokine-cytokine receptor interaction. In protein-protein interaction analysis, platelet factor 4 was selected as the hub gene. To conclude, miR-1-3p is downregulated in CRC and likely suppresses CRC via multiple biological approaches, which indicates the diagnostic potential and tumor suppressive efficacy.

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

BACKGROUND

We recently reported that miR-1 was one of the most significantly downregulated microRNAs in gastric cancer (GC) patients from The Cancer Genome Atlas microRNA sequencing data. Here we aim to elucidate the role of miR-1 in gastric carcinogenesis.

METHODS

We measured miR-1 expression in human GC cell lines and 90 paired primary GC samples, and analyzed the association of its status with clinicopathological features. The effect of miR-1 on GC cells was evaluated by proliferation and migration assay. To identify the target genes of miR-1, bioinformatic analysis and protein array analysis were performed. Moreover, the regulation mechanism of miR-1 with regard to these predicted targets was investigated by quantitative PCR (qPCR), Western blot, ELISA, and endothelial cell tube formation. The putative binding site of miR-1 on target genes was assessed by a reporter assay.

RESULTS

Expression of miR-1 was obviously decreased in GC cell lines and primary tissues. Patients with low miR-1 expression had significantly shorter overall survival compared with those with high miR-1 expression (P = 0.0027). Overexpression of miR-1 in GC cells inhibited proliferation, migration, and tube formation of endothelial cells by suppressing expression of vascular endothelial growth factor A (VEGF-A) and endothelin 1 (EDN1). Conversely, inhibition of miR-1 with use of antago-miR-1 caused an increase in expression of VEGF-A and EDN1 in nonmalignant GC cells or low-malignancy GC cells.

CONCLUSIONS

MiR-1 acts as a tumor suppressor by inhibiting angiogenesis-related growth factors in human gastric cancer. Downregulated miR-1 not only promotes cellular proliferation and migration of GC cells, but may activates proangiogenesis signaling and stimulates the proliferation and migration of endothelial cells, indicating the possibility of new strategies for GC therapy.

The comprehensive expression analysis of circular RNAs in gastric cancer and its association with field cancerization

Circular RNAs comprise a new class of long noncoding RNAs characterized by their 5' and 3' ends covalently joined. Previous studies have demonstrated that some circular RNAs act as microRNA sponges, and are associated with cellular proliferation in cancer. We were the first to analyze the global expression of circular RNAs in samples of patients without gastric cancer, gastric cancer, and matched tumor-adjacent gastric tissue. Among the samples, we identified 736 previously annotated circular RNAs by RNA-Seq. The tumor-adjacent tissue presented the higher abundance of circular RNAs and could not be considered as a normal tissue, reinforcing the notion of field effect in gastric cancer. We identified five differentially expressed circular RNAs that may be potential biomarkers of this type of cancer. We also predicted candidate microRNAs targets of the highest expressed circular RNAs in gastric tissues and found five miRNAs. Overall, our results support the hypothesis of circular RNAs representing a novel factor in the dynamic epigenetic network of gene regulation, which involves the microRNAs, its mRNAs targets, and the circular RNAs-derived genes. Further studies are needed to elucidate the roles and the functional relevance of the circular RNAs in human diseases.

Oligodendrocyte precursor cell transplantation promotes functional recovery following contusive spinal cord injury in rats and is associated with altered microRNA expression

It has been reported that oligodendrocyte precursor cells (OPCs) may be used to treat contusive spinal cord injury (SCC), and may alter microRNA (miRNA/miR) expression following SCC in rats. However, the association between miRNA expression and the treatment of rats with SCC with OPC transplantation remain unclear. The present study transplanted OPCs into the spinal cord of rats with SCC and subsequently used the Basso, Beattie and Bresnahan (BBB) score to assess the functional recovery and pain scores. An miRNA assay was performed to detect differentially expressed miRNAs in the spinal cord of SCC rats transplanted with OPCs, compared with SCC rats transplanted with medium. Quantitative polymerase chain reaction was used to verify significantly altered miRNA expression levels. The results demonstrated that OPC transplantation was able to improve motor recovery and relieve mechanical allodynia in rats with SCC. In addition, through a miRNA assay, 45 differentially expressed miRNAs (40 upregulated miRNAs and 5 downregulated miRNAs) were detected in the spinal cord of rats in the OPC group compared with in the Medium group. Differentially expressed miRNAs were identified according to the following criteria: Fold change >2 and P<0.05. Furthermore, quantitative polymerase chain reaction was used to verify the most highly upregulated (miR‑375‑3p and miR‑1‑3p) and downregulated (miR‑363‑3p, miR‑449a‑5p and miR‑3074) spinal cord miRNAs that were identified in the miRNA assay. In addition, a bioinformatics analysis of these miRNAs indicated that miR‑375 and miR‑1 may act primarily to inhibit cell proliferation and apoptosis via transcriptional and translational regulation, whereas miR‑363, miR‑449a and miR‑3074 may act primarily to inhibit cell proliferation and neuronal differentiation through transcriptional regulation. These results suggested that OPC transplantation may promote functional recovery of rats with SCC, which may be associated with the expression of various miRNAs in the spinal cord, including miR‑375‑3p, miR‑1‑3p, miR‑363‑3p, miR‑449a‑5p and miR‑3074.

Histone acetyltransferase p300/CBP inhibitor C646 blocks the survival and invasion pathways of gastric cancer cell lines

The histone acetyltransferases (HATs) adenovirus E1A-associated protein (p300) and CREB binding protein (CBP) serve as coactivators during a diverse assortment of cellular processes. In the present study, p300 and CBP were highly expressed in 5 gastric cancer (GC) cell lines (SGC‑7901, MKN45, MGC-803, BGC-823 and KATO III) compared with human normal gastric epithelial cell line (GES-1). C646, a selective inhibitor of p300 and CBP, inhibited cell viability and cell cycle and promoted cell apoptosis in all 5 GC cell lines. In addition, C646 suppressed the migration and invasion capability of the GC cell lines, except for the middle-differentiated SGC-7901 cell line. Furthermore, we detected the differential expression of corresponding oncogenic signalling molecules, such as c-Met, Akt, Bcl-2, Bax, cyclin D1, MMP7 and MMP9, in GC cells following C646 treatment. In conclusion, our results suggest that C646 inhibits the acetylation of histone H3 via inactivation of p300 and CBP, resulting in antineoplastic effects toward GC cells. Thus, the selective HAT inhibitor C646 could be a promising antitumour reagent for GC treatment.

MiR-1-3p inhibits the proliferation and invasion of bladder cancer cells by suppressing CCL2 expression

We attempted to analyze the effects of miR-1-3p and CCL2 on the proliferation, migration, and invasion of bladder cancer cells. A total of 18 pairs of bladder cancer tissues with corresponding adjacent tissues and the 6 cases of normal tissues were collected. The expressions of miR-1-3p and CCL2 in the cancer tissues were evaluated using quantitative real-time polymerase chain reaction and western blot. The relationship between miR-1-3p and CCL2 was assessed using luciferase reporter assay. The UM-UC-3 bladder cancer cells were transfected with CCL2 small interfering RNA and miR-1-3p mimics. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony formation assay, wound healing assay, Transwell assay, and the flow cytometry test were used to detect the proliferation, migration, invasion, and apoptosis of bladder cancer cells. Bladder cancer tissues had lower levels of miR-1-3p but higher levels of CCL2 than normal tissues ( p < 0.05). The transfection of miR-1-3p mimics and CCL2 small interfering RNA remarkably suppressed cell proliferation and invasion and promoted apoptosis of cells ( p < 0.05). Results of the luciferase reporter gene assay demonstrated that miR-1-3p targeted CCL2. MiR-1-3p suppresses the proliferation and invasion of urinary bladder cancer cells by targeting CCL2.

MiR-1 suppresses tumor cell proliferation in colorectal cancer by inhibition of Smad3-mediated tumor glycolysis

Aberrant expression of microRNA (miR)-1 has been observed in many human malignancies. However, the function and underlying mechanism of miR-1 remains elusive. To address the specific role of miR-1 in tumor glycolysis using the gain- or loss-of-function studies. Metabolic studies combined with gene expression analysis were performed in vitro and in vivo. We demonstrated aberrant expression of miR-1 in aerobic glycolysis, the Warburg effect, in cancer cells. MiR-1 suppressed aerobic glycolysis and tumor cell proliferation via inactivation of Smad3 and targeting HIF-1α, leading to reduce HK2 and MCT4 expression, which illustrated a novel pathway to mediate aerobic glycolysis in cancer cells. Overexpression of miR-1 mimics significantly decreased tumor glycolysis, including lactate production and glucose uptake, and cell proliferation, and these effects were reversed by ectopic expression of Smad3. Importantly, endogenous Smad3 regulated and interacted with HIF-1α, resulting in increasing activity of Smad3, and this interaction was dramatically abolished by addition of miR-1. We further demonstrated that Smad3 was central to the effects of miR-1 in colorectal cancer cells, establishing a previously unappreciated mechanism by which the miR-1/Smad3/HIF-1α axis facilitates the Warburg effect to promote cancer progression in vitro and in vivo. The results indicate that miR-1 may have an essential role as a tumor suppressor, suggesting its potential role in molecular therapy of patients with advanced colorectal cancer.

Targeting MicroRNAs in Cancer Gene Therapy

MicroRNAs (miRNAs) are a kind of conserved small non-coding RNAs that participate in regulating gene expression by targeting multiple molecules. Early studies have shown that the expression of miRNAs changes significantly in different tumor tissues and cancer cell lines. It is well acknowledged that such variation is involved in almost all biological processes, including cell proliferation, mobility, survival and differentiation. Increasing experimental data indicate that miRNA dysregulation is a biomarker of several pathological conditions including cancer, and that miRNA can exert a causal role, as oncogenes or tumor suppressor genes, in different steps of the tumorigenic process. Anticancer therapies based on miRNAs are currently being developed with a goal to improve outcomes of cancer treatment. In our present study, we review the function of miRNAs in tumorigenesis and development, and discuss the latest clinical applications and strategies of therapy targeting miRNAs in cancer.

Regulation of microRNA-1 (miR-1) expression in human cancer

MicroRNAs (miRs) have been found to play important roles in tumorigenesis, apoptosis, metastasis, and drug resistance in cancer. Among a number of miRs, miR-1 was shown to be predominantly downregulated in almost all examined human cancers. As a tumor suppressor miR involved in post-transcriptional regulation of crucial tumor associated gene expression, miR-1 represents a promising target for anticancer therapy. Re-expression of miR-1 can suppress cancer cell proliferation, promote apoptosis, and reverse drug resistance in cancers both in vitro and in vivo. Recently, the regulatory mechanisms of miR-1 expression have been studied in various cancers in different model systems. In this review, we summarize the mechanisms of miR-1 expression through epigenetic, transcriptional, and post-transcriptional regulation. These regulatory mechanisms of miR-1 expression could help us to understand the functions of altered miR-1 expression and provide valuable insights for further investigations into miR-1 based cancer therapy.

Circulating MicroRNAs in Graves' Disease in Relation to Clinical Activity

BACKGROUND

Understanding the roles of circulating microRNAs (miRNAs) can provide important and novel information regarding disease pathogenesis and a patient's clinical condition. Circulating miRNAs, such as exosomal miRNA, may regulate various bioactivities related to intercellular communication. However, the circulation of miRNAs in Graves' disease (GD) in relation to disease activity has never been elucidated. This study aimed to identify circulating miRNAs in GD in relation to disease activity and whether their exosomes play a role in the pathogenesis of GD.

METHODS

Circulating miRNAs were measured in serum obtained from seven intractable GD patients, seven GD patients in remission, and seven healthy controls using the miScript miRNA PCR Array. Altered miRNAs selected from array data were validated in 65 subjects. To investigate exosome biology, peripheral blood mononuclear cells (PBMCs) were incubated with exosomes isolated from the subjects' sera. mRNAs were quantified for cytokines using quantitative real-time polymerase chain reaction.

RESULTS

Circulating miR-23b-5p and miR-92a-39 were increased in GD patients in remission compared with intractable GD patients (p < 0.05). On the other hand, let-7g-3p and miR-339-5p were decreased in GD patients in remission compared with intractable GD patients (p < 0.05). Exosomes from intractable GD patients stimulated mRNA expression for IL-1β and TNF-α compared with GD patients in remission or healthy controls.

CONCLUSIONS

This study demonstrates that different levels of circulating miRNAs are associated with intractable GD. Moreover, serum exosomes of patients with intractable GD may activate immune cells, which may play an important role in GD pathogenesis.

MicroRNA-1 down-regulates proliferation and migration of breast cancer stem cells by inhibiting the Wnt/β-catenin pathway

We investigated the miRNA profiles of breast cancer stem cells (CSCs) and non-CSC tumor cells by miRNA microarray and determined the effect of altered miR-1 expression on proliferation and migration of breast CSCs. The potential targets of miR-1 in the Wnt/β-catenin signaling were characterized by bioinformatics analysis and luciferase assay. We found that 14 miRNAs were up-regulated and 13 were down-regulated in the ESA⁺CD44⁺CD24⁻lineage⁻ CSCs, related to ESA⁺CD44⁻CD24⁺lineage⁻ non-CSC tumor cells. The miR-1 expression was associated inversely with aggressiveness of breast cancers. Furthermore, enhanced miR-1 expression decreased the percentages of SKBR3/CSCs and miR-1 inhibition increased the percentages of MCF-7/CSCs. Enhanced miR-1 expression significantly reduced the Frizzled 7 and Tankyrase-2 (TNKS2)-regulated luciferase activity in 293T cells and decreased Frizzled 7, TNKS2, c-Myc, octamer-binding transcription factor 4 (Oct4) and Nanog expression and the ratios of nuclear to cytoplasmic β-catenin as well as β-catenin-dependent luciferase activity in breast CSCs in vitro. miR-1 inhibited proliferation, migration and wound healing of breast CSCs in vitro. Enhanced miR-1 expression inhibited the growth of implanted MCF-7/CSCs while miR-1 inhibition promoted the growth of implanted MCF-7/CSCs in vivo. Our data indicate that miR-1 down-regulates breast CSC stemness, proliferation and migration by targeting the Frizzled 7 and TNKS2 to inhibit the Wnt/β-catenin signaling.

ZNF143 enhances metastasis of gastric cancer by promoting the process of EMT through PI3K/AKT signaling pathway

The zinc finger protein 143 (ZNF143) is a transcription factor, which regulates many cell cycle-associated genes. ZNF143 expressed strongly in multiple solid tumors. However, the influence of ZNF143 on gastric cancer (GC) remains largely unknown. In this study, we investigated the ZNF143 mRNA level in GC tissues and cells by quantitative real-time PCR (qRT-PCR). The protein expression of ZNF143 in GC cells, and the signaling pathway proteins were detected by Western blotting. Transwell assay and wound healing assay were performed to explore the effects of ZNF143 for the migration ability of GC cells in vitro. We also performed the tail vein injection in nude mice with GC cells to explore the impact of ZNF143 on GC metastasis in vivo. ZNF143 was overexpressed in specimens of GC compared with adjacent normal tissues and increased more significantly in GC tissues of patients who had lymph node metastasis. Ectopic overexpression of ZNF143 enhanced GC migration, whereas ZNF143 knockdown suppressed this effect in vitro. In vivo, ZNF143 knockdown reduced distant metastasis of GC cells in nude mice. In addition, overexpression of ZNF143 reduced the expression of epithelial cell marker (E-cadherin) and induced the expression of mesenchymal cell marker (N-cadherin,Vimentin), Snail and Slug. We also found that ZNF143 enhanced GC cell migration by promoting the process of EMT through PI3K/AKT signaling pathway. In general, our findings show that ZNF143 expressed strongly in GC and enhanced migration of GC cells in vitro and in vivo. It is conceivable that ZNF143 could be a therapeutic genetic target for GC treatment.

Insights into roles of the miR-1, -133 and -206 family in gastric cancer (Review)

Gastric cancer (GC) remains the third most common cause of cancer deaths worldwide and carries a high rate of metastatic risk contributing to the main cause of treatment failure. An accumulation of data has resulted in a better understanding of the molecular network of GC, however, gaps still exist between the unique bio-resources and clinical application. MicroRNAs are an important part of non-coding RNAs and behave as major regulators of tumour biology, alongside their well-known roles as intrinsic factors of gene expression in cellular processes, via their post-transcriptional regulation of components of signalling pathways in a coordinated manner. Deregulation of the miR-1, -133 and -206 family plays a key role in tumorigenesis, progression, invasion and metastasis. This review aims to provide a summary of recent findings on the miR-1, -133 and -206 family in GC and how this knowledge might be exploited for the development of future miRNA-based therapies for the treatment of GC.

Identification and functional characterization of microRNAs reveal a potential role in gastric cancer progression

PURPOSE

To investigate the potential candidate microRNA (miRNA) biomarkers for the clinical diagnosis, classification, and prognosis of gastric cancer (GC).

METHODS

We use bioinformatics overlapping subclasses analysis to find the tumor grade and lymphatic metastasis-related GC specific miRNAs from the Cancer Genome Atlas (TCGA) database. Then, we further investigated these GC specific miRNAs distributions in different GC clinical features and their correlations overall survival on the basis of GC patients' information and their related RNA sequencing profile from TCGA. Finally, we randomly selected some of key miRNAs use qRT-PCR to confirm the reliability and validity.

RESULTS

22 GC specific key miRNAs were identified (Fold-change >2, P < 0.05), 11 of them were discriminatively expressed with tumor size, grade, TNM stage and lymphatic metastasis (P < 0.05). In addition, nine miRNAs (miR-196b-5p, miR-135b-5p, miR-183-5p, miR-182-5p, miR-133a-3p, miR-486-5p, miR-144-5p, miR-129-5p and miR-145-5p) were found to be significantly associated with overall survival (log-rank P < 0.05). Finally, four key miRNAs (miR-183-5p, miR-486-5p, miR-30c-2-3p and miR-133a-3p) were randomly selected to validation and their expression levels in 53 newly diagnosed GC patients by qRT-PCR. Results showed that the fold-changes between TCGA and qRT-PCR were 100 % in agreement. We also found miR-183-5p and miR-486-5p were significantly correlated with tumor TNM stage (P < 0.05), and miR-30c-2-3p and miR-133a-3p were associated with tumor differentiation degree and lymph-node metastasis (P < 0.05). These verified miRNAs clinically relevant, and the bioinformatics analysis results were almost the same.

CONCLUSION

These key miRNAs may functions as potential candidate biomarkers for the clinical diagnosis, classification and prognosis for GC.

Dual-receptor (EGFR and c-MET) inhibition by tumor-suppressive miR-1 and miR-206 in head and neck squamous cell carcinoma

Our studies of microRNA (miRNA) expression signatures have shown that microRNA-1 (miR-1) and microRNA-206 (miR-206) were downregulated in head and neck squamous cell carcinoma (HNSCC) clinical specimens. The seed sequences of these miRNAs are identical, suggesting that the identification of the molecular targets regulated by miR-1 and miR-206 will provide new insights into novel mechanisms of HNSCC pathogenesis. Our present data showed that restoration of miR-1 and miR-206 significantly inhibited HNSCC cells' aggressiveness. A combination of gene expression data and in silico analysis revealed that several pathways ('pathway in cancer', 'focal adhesion pathway', 'MAPK signaling pathway', 'regulation of actin cytoskeleton pathway' and 'ECM-receptor interaction pathway') were regulated by miR-1 and miR-206. Among them, we found that two growth factor receptors, epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (c-MET), were directly regulated by both miR-1 and miR-206 in HNSCC cells. Also, downstream oncogenic signaling of these receptors was reduced by restoration of miR-1 or miR-206 expression. Moreover, overexpression of EGFR and c-MET was observed in HNSCC clinical specimens. The identification of targets modulated by tumor-suppressive miR-1 and miR-206 may lead to a better understanding of molecular pathogenesis of HNSCC.

Regulation of the MET oncogene: molecular mechanisms

The MET oncogene is a predictive biomarker and an attractive therapeutic target for various cancers. Its expression is regulated at multiple layers via various mechanisms. It is subject to epigenetic modifications, i.e. DNA methylation and histone acetylation. Hypomethylation and acetylation of the MET gene have been associated with its high expression in some cancers. Multiple transcription factors including Sp1 and Ets-1 govern its transcription. After its transcription, METmRNA is spliced into multiple species in the nucleus before being transported to the cytoplasm where its translation is modulated by at least 30 microRNAs and translation initiation factors, e.g. eIF4E and eIF4B. METmRNA produces a single chain pro-Met protein of 170 kDa which is cleaved into α and β chains. These two chains are bound together through disulfide bonds to form a heterodimer which undergoes either N-linked or O-linked glycosylation in the Golgi apparatus before it is properly localized in the membrane. Upon interactions with its ligand, i.e. hepatocyte growth factor (HGF), the activity of Met kinase is boosted through various phosphorylation mechanisms and the Met signal is relayed to downstream pathways. The phosphorylated Met is then internalized for subsequent degradation or recycle via proteasome, lysosome or endosome pathways. Moreover, the Met expression is subject to autoregulation and activation by other EGFRs and G-protein coupled receptors. Since deregulation of the MET gene leads to cancer and other pathological conditions, a better understanding of the MET regulation is critical for Met-targeted therapeutics.