High expression of miR-16 and miR-451 predicating better prognosis in patients with gastric cancer

A 9‑gene expression signature to predict stage development in resectable stomach adenocarcinoma

BACKGROUND

Stomach adenocarcinoma (STAD) is a highly heterogeneous disease and is among the leading causes of cancer-related death worldwide. At present, TNM stage remains the most effective prognostic factor for STAD. Exploring the changes in gene expression levels associated with TNM stage development may help oncologists to better understand the commonalities in the progression of STAD and may provide a new way of identifying early-stage STAD so that optimal treatment approaches can be provided.

METHODS

The RNA profile retrieving strategy was utilized and RNA expression profiling was performed using two large STAD microarray databases (GSE62254, n = 300; GSE15459, n = 192) from the Gene Expression Omnibus (GEO) and the RNA-seq database within the Cancer Genome Atlas (TCGA, n = 375). All sample expression information was obtained from STAD tissues after radical resection. After excluding data with insufficient staging information and lymph node number, samples were grouped into earlier-stage and later-stage. Samples in GSE62254 were randomly divided into a training group (n = 172) and a validation group (n = 86). Differentially expressed genes (DEGs) were selected based on the expression of mRNAs in the training group and the TCGA group (n = 156), and hub genes were further screened by least absolute shrinkage and selection operator (LASSO) logistic regression. Receiver operating characteristic (ROC) curves were used to evaluate the performance of the hub genes in distinguishing STAD stage in the validation group and the GSE15459 dataset. Univariate and multivariate Cox regressions were performed sequentially.

RESULTS

22 DEGs were commonly upregulated (n = 19) or downregulated (n = 3) in the training and TCGA datasets. Nine genes, including MYOCD, GHRL, SCRG1, TYRP1, LYPD6B, THBS4, TNFRSF17, SERPINB2, and NEBL were identified as hub genes by LASSO-logistic regression. The model achieved discrimination in the validation group (AUC = 0.704), training-validation group (AUC = 0.743), and GSE15459 dataset (AUC = 0.658), respectively. Gene Set Enrichment Analysis (GSEA) was used to identify the potential stage-development pathways, including the PI3K-Akt and Calcium signaling pathways. Univariate Cox regression indicated that the nine-gene score was a significant risk factor for overall survival (HR = 1.28, 95% CI 1.08-1.50, P = 0.003). In the multivariate Cox regression, only SCRG1 was an independent prognostic predictor of overall survival after backward stepwise elimination (HR = 1.21, 95% CI 1.11-1.32, P < 0.001).

CONCLUSION

Through a series of bioinformatics and validation processes, a nine-gene signature that can distinguish STAD stage was identified. This gene signature has potential clinical application and may provide a novel approach to understanding the progression of STAD.

Isolation and Characterization of Extracellular Vesicles from Gastric Juice

Simple Summary

Gastric cancer (GC) is one of the most common cancers and the fifth leading cause of cancer-related deaths worldwide. The steadily growing interest in secreted extracellular vesicles (EVs) is related to their ability to carry a variety of biologically active molecules, which can be used as markers for liquid noninvasive diagnosis of malignant neoplasms. For these applications, blood is the most widely used source of EVs. However, this body fluid contains an extremely heterogeneous mixture of EVs originating from different types of normal cells and tissues. The aim of this study was to assess the possibility of using gastric juice (GJ) as an alternative source of EVs since it is expected to be enriched in vesicles of tumor origin. We validated the presence of EVs in GJ using transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western-blot analysis of exosomal markers, showed for the first time the feasibility of their isolation by ultracentrifugation and demonstrated the prospect of using GJ-derived EVs as a source of GC miRNA markers.

Abstract

EVs are involved in local and distant intercellular communication and play a vital role in cancer development. Since EVs have been found in almost all body fluids, there are currently active attempts for their application in liquid diagnostics. Blood is the most commonly used source of EVs for the screening of cancer markers, although the percentage of tumor-derived EVs in the blood is extremely low. In contrast, GJ, as a local biofluid, is expected to be enriched with GC-associated EVs. However, EVs from GJ have never been applied for the screening and are underinvestigated overall. Here we show that EVs can be isolated from GJ by ultracentrifugation. TEM analysis showed high heterogeneity of GJ-derived EVs, including those with exosome-like size and morphology. In addition to morphological diversity, EVs from individual GJ samples differed in the composition of exosomal markers. We also show the presence of stomatin within GJ-derived EVs for the first time. The first conducted comparison of miRNA content in EVs from GC patients and healthy donors performed using a pilot sampling revealed the significant differences in several miRNAs (-135b-3p, -199a-3p, -451a). These results demonstrate the feasibility of the application of GJ-derived EVs for screening for miRNA GC markers.

The outcome of intravenous and inhalation anesthesia after pancreatic cancer resection: a retrospective study

BACKGROUND

Different types of anesthesia may affect cancer patient's outcomes, we compared the overall survival (OS) and disease-free survival (DFS) of patients with pancreatic cancer under total intravenous and inhalation anesthesia.

METHODS

The authors collected the electronic medical records of patients who had accepted at a pancreatectomy from January 1, 2010 to December 31, 2016. Patients respectively received total intravenous anesthesia (TIVA) or inhalational anesthesia (INHA). Stabilized inverse probability of treatment weighting (SIPTW)was used to minimize differences. Kaplan-Meier survival was established to analyze the influence of sort of anesthesia on disease-free and overall survival. We compare the effects of each sort of anesthesia on cancer recurrence or metastasis and all-cause mortality.

RESULTS

A total of 463 patients who had undergone pancreatic cancer resection were collected in this study, of which 421 patients were available (TIVA group, n = 114 INHA group, n = 307). After SIPTW there were no significant differences between the two groups in disease-free survival (hazard ratio, 1.01, 95%CI, 0.78 to 1.29, P = 0.959) or overall survival (hazard ratio, 1.11, 95%CI, 0.87 to 1.42, P = 0.405).

CONCLUSIONS

In conclusion, the present study showed no significant difference in overall survival and disease-free survival between total intravenous anesthesia and volatile anesthesia.

Bone marrow mesenchymal stem cells-derived exosomal microRNA-16-5p restrains epithelial-mesenchymal transition in breast cancer cells via EPHA1/NF-κB signaling axis

OBJECTIVE

This study intends to conquer the mystery of microRNA-16-5p/erythropoietin-producing hepatocellular A1/nuclear factor-κB signaling (miR-16-5p/EPHA1/NF-κB signaling) in breast cancer.

METHODS

Expression of miR-16-5p, EPHA1 and NF-κB signaling-related proteins were detected. Gene overexpression or silencing was used to examine the biological roles of bone marrow mesenchymal stem cells (BMSCs)-derived exo-miR-16-5p in breast cancer. The effect of exo-miR-16-5p on tumorigenesis of breast cancer was confirmed by the xenograft nude mouse model.

RESULTS

Low miR-16-5p and high EPHA1 expression were examined in breast cancer. BMSCs-derived exosomes, up-regulated miR-16-5p or down-regulated EPHA1 restrained epithelial-mesenchymal transition (EMT) of breast cancer cells and tumor growth in nude mice. Down-regulated miR-16-5p or up-regulated EPHA1 activated NF-κB signaling. Knockdown of EPHA1 or inhibition of NF-κB signaling reversed the effects of down-regulated miR-16-5p on breast cancer cells.

CONCLUSION

BMSCs-derived exosomal miR-16-5p hinders breast cancer cells progression via EPHA1/NF-κB signaling axis.

Clinical Potential of miR-451 and miR-506 as a Prognostic Biomarker in Patients with Breast Cancer

BACKGROUND

The incidence and mortality of breast cancer in the world remain high. The function and important role of miR-451 and miR-506 in a series of cancers have been proved. The purpose of this research was to explore the clinical diagnosis and prognostic significance of miR-451 and miR-506 expression in breast cancer.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect miR-451 and miR-506 expression in serum and tissues. The relationship of miR-451 and miR-506 with clinical parameters was determined by the chi-square test. Receiver operating characteristics (ROC) analysis was conducted to evaluate the diagnostic accuracy of miR-451 and miR-506 in breast cancer. In addition, we determined the prognostic performance of miR-451 and miR-506 using Kaplan-Meier survival assay.

RESULTS

The expression of miR-451 and miR-506 in breast cancer patients was significantly lower than that in healthy people. miR-451 and miR-506 expression decreased in breast cancer tissues compared with paracancerous tissue. High expression of miR-451 and miR-506 was associated with positive lymph node metastasis and late tumor node metastasis stage. Breast cancer patients with high miR-451 and miR-506 expression had lower five-year survival rate. The level of miR-451 and miR-506 expression showed high diagnostic accuracy for distinguishing breast cancer patients and healthy people.

CONCLUSION

miR-451 and miR-506 could be used as biomarker for the diagnosis and prognosis of breast cancer.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

Aberrant Non-Coding RNA Expressed in Gastric Cancer and Its Diagnostic Value

Gastric cancer (GC) is one of the digestive tract malignancies with high invasion and mortality rates. Recent studies have reported that non-coding RNAs (ncRNAs) seem to play a crucial part in many tumors. Due to their high stability, ncRNAs may used as novel biomarkers to predict the occurrence and prognosis of GC. Here, we measured miRNA, lncRNA and cirRNA expression profiles of GC patients by using microarray and RNA-sequencing data from tissue samples. The diagnosis prediction model based on the ncRNA signatures and clinical features was evaluated by circulating and tissue validation and ROC analysis. Nine miRNAs and eight lncRNAs were obtained from the microarray analysis. Six miRNAs (miR-550a-5p, miRNA-936, miR-1306-3p, miR-3185, miR-6083, miR-6792-3p) and three lncRNAs (lnc-MB21D1-3:5, lnc-PSCA-4:2 and lnc-ABCC5-2:1) were abnormally expressed in circulating and tissue samples compared with normal control (NC), which was closely related to clinical pathology and survival time of GC patients; circRNA sequencing and qRT-PCR revealed four circRNAs (circASHL2, circCCDC9, circNHSL1 and cirMLLT10) were abnormally expressed in GC tissues and parts of them were negative relationship with their predicted binding miRNAs. These ncRNAs might act as promising molecular markers for the diagnosis and prognosis of gastric cancer.

Micro-RNA-451 Reduces Proliferation of B-CPAP Human Papillary Thyroid Cancer Cells by Downregulating Expression of Activating Transcription Factor 2

Background

MicroRNAs (miRNAs) are novel biomarkers that are important in tumorigenesis and cancer treatment resistance. miR-451 is expressed in human papillary thyroid carcinoma (PTC) tissues and is associated with tumor progression. This study investigated the molecular mechanism associated with the effects of miR-451 on B-CPAP human PTC cells in vitro.

Material/Methods

Binding of miRNAs to the 3′ untranslated region (3′UTR) of messenger RNA (mRNA) was determined with a luciferase reporter assay. miRNAs and plasmids were transfected into human PTC B-CPAP cells with Lipofectamine 2000 Transfection Reagent. Cell viability was tested with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. The levels of miRNAs and mRNA were determined with quantitative polymerase chain reaction and protein levels were analyzed with immunoblotting.

Results

miR-451 bound to wild-type but not mutant 3′-UTR of activating transcription factor 2 (ATF2). MiR-451 mimics inhibited the growth of B-CPAP cells and reduced mRNA and protein levels in ATF2, whereas miR-451 inhibitors promoted the growth of B-CPAP cells and increased mRNA and protein levels in ATF2.

Conclusions

miR-451 directly bound to the 3′UTR of ATF2, decreased mRNA and protein levels in ATF2, and inhibited growth of B-CPAP cells. Our findings suggest that miR-451 may be a potential therapeutic target for PTC.

Human umbilical cord mesenchymal stem cells-derived exosomal microRNA-451a represses epithelial-mesenchymal transition of hepatocellular carcinoma cells by inhibiting ADAM10

Exosomes derived from human umbilical cord mesenchymal stem cells (hucMSCs) expressing microRNAs (miRNAs) have been highlighted in human cancers. However, the detailed molecular mechanism of hucMSCs-derived exosomal miR-451a on hepatocellular carcinoma (HCC) remains further investigation. Our study aims to explore the impact of exosomal miR-451a on the progression of HCC. Expression of miR-451a and a disintegrin and metalloprotease 10 (ADAM10) in HCC tissues and adjacent normal tissues were determined. The exosomes were extracted from hucMSCs and co-cultured with Hep3B and SMMC-7721 cell lines. After the treatment of relative exosomes or exosome inhibitor GW4869 in Hep3B and SMMC-7721 cells, the paclitaxel resistance and malignant phenotypes of HCC cells were measured. Moreover, the effect of hucMSCs-derived exosomes on the expression of miR-451a and ADAM10 in HCC cells was assessed. The targeting relationship between miR-451a and ADAM10 was verified to detect the impact of ADAM10-wild type and ADAM10-mutant type (MUT) on HCC cell processes. Low expression of miR-451a and high expression of ADAM10 indicated a poor prognosis of HCC patients. MiR-451a was up-regulated while ADAM10 was down-regulated in HCC cells after co-culture with HucMSC-derived exosomes. The exosomes elevated miR-451a and inhibited ADAM10 to suppress the paclitaxel resistance, cell cycle transition, proliferation, migration and invasion, and promote apoptosis of HCC cells. ADAM10 was verified to be a target gene of miR-451a. ADAM10-MUT promoted HCC process independent of miR-451a mimic. HucMSC-derived exosomal miR-451a could restrict the epithelial-mesenchymal transition of HCC cells by targeting ADAM10, which might provide new targets for HCC treatment.

Induced pluripotent stem cells-derived microvesicles accelerate deep second-degree burn wound healing in mice through miR-16-5p-mediated promotion of keratinocytes migration

Background: Induced pluripotent stem cells (iPSCs) have emerged as a promising treatment paradigm for skin wounds. Extracellular vesicles are now recognized as key mediators of beneficial stem cells paracrine effects. In this study, we investigated the effect of iPSCs-derived microvesicles (iPSCs-MVs) on deep second-degree burn wound healing and explored the underlying mechanism. Methods: iPSCs-MVs were isolated and purified from conditioned medium of iPSCs and confirmed by electron micrograph and size distribution. In deep second-degree burn model, iPSCs-MVs were injected subcutaneously around wound sites and the efficacy was assessed by measuring wound closure areas, histological examination and immunohistochemistry staining. In vitro, CCK-8, EdU staining and scratch assays were used to assess the effects of iPSCs-MVs on proliferation and migration of keratinocytes. Next, we explored the underlying mechanisms by high-throughput microRNA sequencing. The roles of the miR-16-5p in regulation of keratinocytes function induced by iPSCs-MVs were assessed. Moreover, the target gene which mediated the biological effects of miR-16-5p in keratinocytes was also been detected. Finally, we examined the effect of local miR-16-5p treatment on deep second degree-burns wound healing in mice. Results: The local transplantation of iPSCs-MVs into the burn wound bed resulted in accelerated wound closure including the increased re-epithelialization. In vitro, iPSCs-MVs could promote the migration of keratinocytes. We also found that miR-16-5p is a critical factor in iPSCs-MVs-induced promotion of keratinocytes migration in vitro through activating p38/MARK pathway by targeting Desmoglein 3 (Dsg3). Finally, we confirmed that local miR-16-5p treatment could boost re-epithelialization during burn wound healing. Conclusion: Therefore, our results indicate that iPSCs-MVs-derived miR-16-5p may be a novel therapeutic approach for deep second-degree burn wound healing.

Association of the Expression Level of miR-16 with Prognosis of Solid Cancer Patients: A Meta-Analysis and Bioinformatic Analysis

Objective

To assess the association between the expression level of miR-16 and prognosis of solid cancer patients by meta-analysis and bioinformatic analysis.

Methods

PubMed, Web of Science, and Embase databases were searched until October 31, 2019, to identify eligible studies reporting the association of the miR-16 status with the prognosis of solid cancer patients. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled, and a heterogeneity test was conducted. Sensitivity analysis and a publication bias test were also carried out. Furthermore, the miRpower database was used to validate the association.

Results

Thirteen articles with 2303 solid cancer patients were included in the meta-analysis. Solid cancer patients with low expression level of miR-16 had shorter survival time (I² = 84.0%, HR = 1.47, 95% CI: 1.13-1.91, P = 0.004). In the subgroup analyses of cancer sites, low miR-16 expression level was associated with poor prognosis in the reproductive system cancers (I² = 33.3%, HR = 1.24, 95% CI: 1.06-1.45, P = 0.008). Sensitivity analysis suggested that the pooled HR was stable and omitting a single study did not change the significance of the pooled HR. Begg's test and Egger's test revealed no publication bias in the meta-analysis. In bioinformatic analysis, the significant association between miR-16 level and prognosis of patients with reproductive system cancers was further confirmed (HR = 1.21, 95% CI: 1.03-1.42, P = 0.017).

Conclusion

Low expression level of miR-16 is an indicator for poor prognosis of solid cancer patients, particularly in reproductive system cancers.

LncRNA RP11-361F15.2 promotes osteosarcoma tumorigenesis by inhibiting M2-Like polarization of tumor-associated macrophages of CPEB4

Long non-coding RNAs (lncRNAs) regulates the initiation and progression of osteosarcoma (OS), specifically lncRNA RP11-361F15.2 has been shown to play prominent roles in tumorigenesis. Previously, M2-Like polarization of tumor-associated macrophages (TAMs) has been identified to play a key role in cancer migration/invasion. Hence, it is essential to understand the role of RP11-361F15.2 in tumorigenesis and its association with M2-Like polarization of TAMs. The results indicate that RP11-361F15.2 is significantly increased in OS tissues, and its expression is positively correlated with cytoplasmic polyadenylation element binding protein 4 (CPEB4) expression and negatively associated with miR-30c-5p expression. Further, overexpression of RP11-361F15.2 increased OS cell migration/invasion and M2-Like polarization of TAMs in vitro, as well as promoted xenograft tumor growth in vivo. Mechanistically, luciferase reporter assays indicated that RP11-361F15.2 upregulated CPEB4 expression by competitively binding to miR-30c-5p. Further, we have identified that RP11-361F15.2 promotes CPEB4-mediated tumorigenesis and M2-Like polarization of TAMs through miR-30c-5p in OS. We also identified that RP11-361F15.2 acts as competitive endogenous RNA (ceRNA) against miR-30c-5p thereby binding and activating CPEB4. This RP11-361F15.2/miR-30c-5p/CPEB4 loop could be used as a potential therapeutic strategy for the treatment of OS.

miR-451: A Novel Biomarker and Potential Therapeutic Target for Cancer

MicroRNAs (miRNAs) are endogenous, non-coding, single-stranded small RNAs involved in a variety of cellular processes, including ontogeny, cell proliferation, differentiation, and apoptosis. They can also function as oncogenes or tumor suppressor genes. Recent studies have revealed that miRNA-451 (miR-451) is involved in the regulation of various human physiological and pathological processes. Furthermore, it has been shown that miR-451 not only directly affects the biological functions of tumor cells but also indirectly affects tumor cell invasion and metastasis upon secretion into the tumor microenvironment via exosomes. Thus, miR-451 also influences the progression of tumorigenesis and drug resistance. This review summarizes the expression of miR-451 in various cancer types and the relationship between miR-451 and the diagnosis, treatment, and drug resistance of solid tumors. In addition, we address possible mechanisms of action of miR-451 and its potential application as a biomarker in the diagnosis and treatment of human cancers.

Prognostic value of microRNA-451 in various cancers: A meta-analysis

BACKGROUND

Increasing evidence shows microRNA-451 plays a crucial role in various tumors, but there is inconsistency. The aim of this study was to explore the prognostic role of miR-451 in various tumors.

METHODS

Online PubMed, EMBASE, Web of Science, and the Cochrane library database were searched through February 2019. Hazard ratios (HRs) were extracted and used to describe the association between expression of microRNA-451 and survival outcome, and the correlation between microRNA-451 and clinicopathologic features were described by pooled odds ratios (ORs).

RESULTS

Sixteen retrospective studies containing 2122 patients were incorporated in this meta-analysis. High expression of miR-451 was considered statistically associated with prolonged overall survival (OS) (HR = 0.62, 95% CI 0.49-0.80, p < 0.001) as well as RFS/DFS (HR = 0.55, 95% CI 0.42-0.71, p < 0.001) compared with low expression of miR-451. Besides, the pooled ORs revealed significant association between high expression of miR-451 with lymph node invasion (yes vs. no) (OR = 0.64, 95% CI 0.46-0.90, P = 0.01), tumor diameter (big vs. small) (OR = 0.77, 95% CI 0.60-0.97, P = 0.028) and tumor stage (III + IV vs. I + II) (OR = 0.62, 95% CI 0.42-0.93, P = 0.019).

CONCLUSION

MicroRNA-451 may serve as a promising clinical prognostic biomarker in various carcinomas.

MicroRNAs as Potential Biomarkers for Chemoresistance in Adenocarcinomas of the Esophagogastric Junction

Concerning adenocarcinomas of the esophagogastric junction, neoadjuvant chemotherapy is regularly implemented, but patients' response varies greatly, with some cases showing no therapeutic effect, being deemed as chemoresistant. Small, noncoding RNAs (miRNAs) have evolved as key players in biological processes, including malignant diseases, often promoting tumor growth and expansion. In addition, specific miRNAs have been implicated in the development of chemoresistance through evasion of apoptosis, cell cycle alterations, and drug target modification. We performed a retrospective study of 33 patients receiving neoadjuvant chemotherapy by measuring their miRNA expression profiles. Histologic tumor regression was evaluated using resection specimens, while miRNA profiles were prepared using preoperative biopsies without prior therapy. A preselected panel of 96 miRNAs, known to be of importance in various malignancies, was used to test for significant differences between responsive (chemosensitive) and nonresponsive (chemoresistant) cases. The cohort consisted of 12 nonresponsive and 21 responsive cases with the following 4 miRNAs differentially expressed between both the groups: hsa-let-7f-5p, hsa-miRNA-221-3p, hsa-miRNA-31-5p, and hsa-miRNA-191-5p. The former 3 showed upregulation in chemoresistant cases, while the latter showed upregulation in chemosensitive cases. In addition, significant correlation between high expression of hsa-miRNA-194-5p and prolonged survival could be demonstrated (p value <0.0001). In conclusion, we identified a panel of 3 miRNAs predicting chemoresistance and a single miRNA contributing to chemosensitivity. These miRNAs might function as prognostic biomarkers and enable clinicians to better predict the effect of one or more reliably select patients benefitting from (neoadjuvant) chemotherapy.

A comprehensive review on miR-451: A promising cancer biomarker with therapeutic potential

MicroRNAs (miRNAs) are proposed as a family of short noncoding molecules able to manage and control the expression of the gene targets at the posttranscriptional level. They contribute in several fundamental physiological mechanisms as well as a verity of human and animal diseases such as cancer progression. Among these tiny RNAs, miR-451 placed on chromosome 17 at 17q11.2 presents an essential role in many biological processes in health condition and also in pathogenesis of different diseases. Besides, it has been recently considered as a valuable biomarker for cancer detection, prognosis and treatment. Therefore, this review will provide the critical functions of miR-451 on biological mechanisms including cell cycle and proliferation, cell survival and apoptosis, differentiation and development as well as disease initiation and progression such as tumor formation, migration, invasion, and metastasis.

Oncogenic role of long non-coding RNA SNHG12 in gastric cancer cells by targeting miR-16

The long non-coding RNA small nucleolar RNA host gene 12 (SNHG12) has recently been reported to have an oncogenic role in gastric cancer (GC), but the molecular mechanisms remain largely elusive. In the present study, it was observed that SNHG12 was significantly upregulated in GC tissues and cell lines. High expression of SNHG12 was associated with GC progression and poor prognosis of patients. Knockdown of SNHG12 markedly inhibited the proliferation and migration of the BGC823 and HGC27 GC cell lines. MicroRNA (miR)-16 was identified as a target of SNHG12, and its expression was negatively regulated by SNHG12 in BGC823 and HGC27 cells. In addition, the expression of miR-16 was significantly decreased in GC tissues and cell lines, and inversely associated with the expression of SNHG12 in GC tissues. Furthermore, knockdown of miR-16 impaired the inhibitory effects on GC cell proliferation and migration induced by downregulation of SNHG12. In conclusion, the present study demonstrates that inhibition of SNHG12 suppresses GC cell proliferation and migration by modulation of miR-16 expression, and thus suggests that the SNHG12/miR-16 interaction may be used as a promising target for GC treatment.

Serum miR-16 as a potential biomarker for human cancer diagnosis: results from a large-scale population

BACKGROUND

Cancer is a serious public health problem worldwide, and difficulty in early diagnosis has been the chief obstacle to improve the prognosis of patients. Recently, microRNAs (miRNAs) were widely studied to be potential biomarkers for cancer detection. miR-16 is a prevalent but sophisticated one. In the current study, we aimed to assess the diagnostic value of serum miR-16 for cancer detection.

METHODS

A total of 1458 cancer patients, containing ten types of cancers, and 1457 non-cancer controls were recruited in this study. qRT-PCR was used for the amplification of miRNAs. In addition, a meta-analysis of reported studies was performed to confirm our findings systematically.

RESULTS

Consequently, miR-16 was down-regulated in ESCC, GCA and GNCA patients compared with NCs (all P < 0.001), while up-regulated in PDAC patients (P = 0.001), LAC, LSCC and EEC patients (all P < 0.001). But no significant differences were observed in CRC, EOC and TC patients when compared to NCs (P = 0.747, 0.235 and 0.268, respectively). The areas under the receiver operating characteristic (ROC) curve of miR-16 in GCA, ESCC, LAC, LSCC, GNCA, PDAC and EEC were 0.881, 0.780, 0.757, 0.693, 0.602, 0.614 and 0.681, respectively. Results of meta-analysis showed that miR-16 achieved an overall pooled sensitivity of 0.72, specificity of 0.79, and AUC of 0.85, suggesting that miR-16 was a promising biomarker in cancer detection.

CONCLUSIONS

We provided a comprehensive view of the diagnostic value of serum miR-16 in cancer diagnosis, and confirmed that circulating miR-16 could play an important role in cancer detection.

Optimizing miRNA-module diagnostic biomarkers of gastric carcinoma via integrated network analysis

Several microRNAs (miRNAs) have been suggested as novel biomarkers for diagnosing gastric cancer (GC) at an early stage, but the single-marker strategy may ignore the co-regulatory relationships and lead to low diagnostic specificity. Thus, multi-target modular diagnostic biomarkers are urgently needed. In this study, a Z_summary and NetSVM-based method was used to identify GC-related hub miRNAs and activated modules from clinical miRNA co-expression networks. The NetSVM-based sub-network consisting of the top 20 hub miRNAs reached a high sensitivity and specificity of 0.94 and 0.82. The Z_summary algorithm identified an activated module (miR-486, miR-451, miR-185, and miR-600) which might serve as diagnostic biomarker of GC. Three members of this module were previously suggested as biomarkers of GC and its 24 target genes were significantly enriched in pathways directly related to cancer. The weighted diagnostic ROC AUC of this module was 0.838, and an optimized module unit (miR-451 and miR-185) obtained a higher value of 0.904, both of which were higher than that of individual miRNAs. These hub miRNAs and module have the potential to become robust biomarkers for early diagnosis of GC with further validations. Moreover, such modular analysis may offer valuable insights into multi-target approaches to cancer diagnosis and treatment.

Expression profile of circulating microRNAs in the Correa pathway of progression to gastric cancer

Background

Helicobacter pylori infection causes long-term chronic active gastritis, a risk factor for the intestinal and diffuse forms of gastric cancer. Most gastric cancers develop in a stepwise progression from chronic active gastritis to precursor lesions of gastric cancer. The early detection of gastric cancer improves survival. Studies with recent evidence have proposed circulating-microRNAs as biomarkers of cancer.

Objective

The purpose of this study was to explore the circulating-microRNA profile from H. pylori infection to gastric adenocarcinoma.

Methods

One hundred and twenty-three patients were enrolled and assigned to the discovery or the validation sets. In the discovery phase, circulating-microRNAs were measured by dye-based quantitative polymerase chain reaction and a selection of circulating-microRNAs was validated by probe-based quantitative polymerase chain reaction. A quality control protocol was used.

Results

One hundred and sixty-seven circulating-microRNAs were detected. Precursor lesions of gastric cancer and gastric cancer patients showed the downregulation of eight and five circulating-microRNAs, respectively. We further validated the deregulation of miR-196a-5p in precursor lesions of gastric cancer and the deregulation of miR-134-5p, miR-144-3p and miR-451a in gastric cancer. However, circulating-microRNAs exhibited moderate diagnostic performance due to the overlap of circulating-microRNA expression between non-cancer and cancer patients. miR-144-3p/miR-451a expression levels were correlated. Interestingly, these microRNAs are in 17q11.2, a site of rearrangements associated with gastric cancer.

Conclusion

Circulating-microRNAs are deregulated in precancerous and gastric cancer patients but efforts are needed to improve their diagnostic accuracy.

Prognostic value of microRNAs in gastric cancer: a meta-analysis

BACKGROUND

Previous articles have reported that expression levels of microRNAs (miRNAs) are associated with survival time of patients with gastric cancer (GC). A systematic review and meta-analysis was performed to study the outcome of it.

DESIGN

Meta-analysis.

METHODS

English studies estimating expression levels of miRNAs with any of survival curves in GC were identified up till March 19, 2017 through performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews by two authors independently. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were used to estimate the correlation between miRNA expression and overall survival (OS).

RESULTS

Sixty-nine relevant articles about 26 miRNAs with 6148 patients were ultimately included. GC patients with high expression of miR-20b (HR=2.38, 95%CI=1.16-4.87), 21 (HR=1.77, 95%CI=1.01-3.08), 106b (HR=1.84, 95%CI=1.15-2.94), 196a (HR=2.66, 95%CI=1.94-3.63), 196b (HR=1.67, 95%CI=1.38-2.02), 214 (HR=1.84, 95%CI=1.27-2.67) or low expression of miR-125a (HR=2.06, 95%CI=1.26-3.37), 137 (HR=3.21, 95%CI=1.68-6.13), 141 (HR=2.47, 95%CI=1.34-4.56), 145 (HR=1.62, 95%CI=1.07-2.46), 146a (HR=2.60, 95%CI=1.63-4.13), 206 (HR=2.85, 95%CI=1.73-4.70), 218 (HR=2.61, 95%CI=1.74-3.92), 451 (HR=1.73, 95%CI=1.19-2.52), 486-5p (HR=2.45, 95%CI=1.65-3.65), 506 (HR=2.07, 95%CI=1.33-3.23) have significantly poor OS (P<0.05).

CONCLUSIONS

In summary, miR-20b, 21, 106b, 125a, 137, 141, 145, 146a, 196a, 196b, 206, 214, 218, 451, 486-5p and 506 demonstrate significantly prognostic value. Among them, miR-20b, 125a, 137, 141, 146a, 196a, 206, 218, 486-5p and 506 are strong biomarkers of prognosis in GC.

Comprehensive analysis of aberrantly expressed microRNA profiles reveals potential biomarkers of human lung adenocarcinoma progression

Lung adenocarcinoma (LUAD) is a complex disease that poses challenges for diagnosis and treatment. The aim of the present study is to investigate LUAD-specific key microRNAs (miRNAs) from large-scale samples in The Cancer Genome Atlas (TCGA) database. We used an integrative computational method to identify LUAD-specific key miRNAs related to TNM stage and lymphatic metastasis from the TCGA database. Twenty-five LUAD-specific key miRNAs (fold change >2, p<0.05) from the TCGA database were investigated, and 15 were found to be aberrantly expressed with respect to clinical features. Three miRNAs were correlated with overall survival (log-rank p<0.05). Then, 5 miRNAs were randomly selected for verification of expression in 53 LUAD patient tissues using qRT-PCR. Diagnostic value of these above 5 miRNAs was determined by areas under receiver operating characteristic curves (ROC). Finally, the LUAD-related miRNA miR-30a-3p was selected for verification of biologic function in A549 cells. The results of tests for cell proliferation, apoptosis, and target genes suggested that miR-30a-3p decreases cell proliferation and promotes apoptosis through targeting AKT3. Therefore, miR-30a-3p may be a promising biomarker for the early screening of high-risk populations and early diagnosis of LUAD. Our studies provide insights into identifying novel potential biomarkers for diagnosis and prognosis of LUAD.

MicroRNAs在结直肠癌中的研究进展

结直肠癌在我国恶性肿瘤中的发病率较高, 且其死亡率居高不下. 目前, 越来越多的学者十分关注微小RNAs(microRNAs, miRNAs)与结直肠癌的关系. miRNAs是普遍存在于生物体内的一类小分子非编码RNA, miRNAs的异常表达与结直肠癌的发生和进展密切相关. miRNAs可以通过转录后基因调控的方式, 来影响肿瘤细胞的增殖、调亡以及对化疗的敏感性等. 在这里, 我们回顾了近年来关于miRNAs与结直肠癌的相关文献, 了解miRNAs在结直肠癌中的表达、结直肠癌化疗耐药以及其与预后的关系, 从而更好的了解结直肠癌进展的生物学过程, 有助于结直肠癌的诊断与治疗, 提高结直肠癌患者的预后.