Down-regulation of miR-133a and miR-539 are associated with unfavorable prognosis in patients suffering from osteosarcoma

Emerging roles of MiR-133a in human cancers

MicroRNAs (miRNAs) can post-transcriptionally regulate the expression of cancer-relevant genes via binding to the 3'-untranslated region (3'-UTR) of the target mRNAs. MiR-133a, as a miRNA, participate in tumorigenesis, progression, autophagy and drug-resistance in various malignancies. Based on the recent insights, we discuss the functions of miR-133a in physiological and pathological processes and its potential effects on cancer diagnosis, prognosis and therapy.

Microbial regulation of a lincRNA-miRNA-mRNA network in the mouse hippocampus

Aim: To comprehensively understand microbiota-regulated lincRNA-miRNA-mRNA networks in psychiatric disorders. Materials & methods: Integrated analyses of lincRNAs, mRNAs and miRNAs, obtained by microarray analysis of hippocampus from specific pathogen-free, germ-free and colonized germ-free mice, were performed. Results: Expression of 139 mRNAs, seven miRNAs and one lincRNA was restored following colonization. The restored transcripts were mainly involved in CREB and Ras/MAPK signaling pathways. RNA transcription and post-transcriptional regulation were the primary perturbed functions. Finally, 12 lincRNAs, six miRNAs and 47 mRNAs were included in a lincRNA-miRNA-mRNA network, and lincRNA0926-miR-190a-5p-Celf4 interactions may play a pivotal role in this regulatory network. Conclusion: This study provides clues for understanding the molecular basis of gut microbiota-brain interactions in depressive- and anxiety-like behaviors.

MicroRNA-539 inhibits the progression of Wilms' Tumor through downregulation of JAG1 and Notch1/3

BACKGROUND

Previous studies demonstrated that miR-539 play an important role in the carcinogenesis of some cancers. The aim of the present study was to determine the role of miR-539 in the pathogenesis of Wilms' Tumor (WT).

METHODS

The expression level of miR-539 was measured by qRT-PCR in 42 WT tissues and SK-NEP-1 cell line. Protein expression of genes (E-cadherin, N-cadherin, Vimentin, Notch 1, Notch 3 and JAG1) was assessed by Western blot. The function of miR-539 was investigated in SK-NEP-1 cells by MTT and Transwell assays. The relationship between miR-539 and JAG1 was verified by a dual luciferase assay in SK-NEP-1 cells.

RESULTS

The expression level of miR-539 was significantly decreased in WT tissues. Downregulation of miR-539 was closely related to NWTS-5 stage, lymph node metastasis and histological type of WT patients. Furthermore, low miR-539 expression was associated with a shorter overall survival rate in WT patients. In vitro, overexpression of miR-539 suppressed proliferation, migration and invasion of SK-NEP-1 cells. In addition, JAG1 was a direct target of miR-539. MiR-539 inhibited the development of WT by inhibiting JAG1-Notch1/3 expressing and blocking EMT.

CONCLUSION

MiR-539 inhibited the progression of WT through downregulation of JAG1 and Notch1/3.

miR-539-3P inhibits proliferation and invasion of gastric cancer cells by targeting CTBP1

Gastric cancer is the fifth most lethal carcinoma in the world. Genetic and epigenetic factors transform the normal cells into malignant cells and lead to tumor development. MicroRNA (miRNA), a small non-coding RNA which functions in RNA silencing and post-transcriptional regulation of gene expression, is closely associated with cancer initiation and propagation, including stomach cancer. In this study, for the first time, we report miR-539-3P, as a tumor suppressor, was down-regulated in gastric cancer both in vivo and in vitro. In addition, dysfunction of miR-539-3P regulates gastric cancer cell proliferation and invasion. Bioinformatics analysis revealed CTBP1 is the direct target of miR-539-3P and high expression of CTBP1 faciliates the progression of gastric carcinoma through promoting the epithelial to mesenchymal transition (EMT). Overall, these results indicate that epigenetic regulation of CTBP1 through miR-539-3P is critical to gastric cancer and provide a new insight into gastric cancer diagnosis, treatment and prognosis.

Down-regulation of MiR-539 Indicates Poor Prognosis in Patients with Pancreatic Cancer

It has been demonstrated that miR-539 plays an important role in the development and progression of tumors. The purpose of this study was to analyze the correlation between the expression level of miR-539 and the clinicopathological features and prognosis of patients with pancreatic cancer. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze the expression level of miR-539 in 60 patients with pancreatic cancer. It was found that miR-539 gene expression was down-regulated in pancreatic cancer compared with that in paracancerous tissues. In addition, the expression level of miR-539 was inversely correlated with tumor differentiation (poorly to moderately differentiated vs. well differentiated, P=0.006), lymph node metastasis (positive vs. negative, P=0.006), clinical stage (III-IV vs. I-II, P=0.002), CA199 (≥200 vs. <200, P=0.019) and distant metastasis (positive vs. negative, P=0.035). The survival time of pancreatic cancer patients with low expression of miR-539 was significantly shorter than that of patients with high expression of miR-539. Multivariate analysis suggested that miR-539 expression level was an independent prognostic indicator for patients with pancreatic cancer (P=0.025). Down-regulation of miR-539 may be a potentially unfavorable prognostic factor for patients with pancreatic cancer, and further studies are needed to confirm our conclusion in the future.

Astragalus polysaccharides decrease proliferation, migration, and invasion but increase apoptosis of human osteosarcoma cells by up-regulation of microRNA-133a

Osteosarcoma (OS) has a high incidence, malignity, and frequency of recurrence and metastasis. In this study, we aimed to explore the potential anti-cancer effects of Astragalus polysaccharides (APS) on human OS MG63 cells as well as underlying mechanisms. Viability of MG63 cells was assessed by CCK-8 assay to determine the adequate concentration of APS. Then, effects of APS on MG63 cell proliferation, cell cycle distribution, apoptosis, and migration and invasion were analyzed by BrdU incorporation, PI staining, flow cytometry, and transwell assays, respectively. The expression levels of proteins involved in these physiological processes were assessed by western blot analysis. Afterwards, miR-133a level in APS-treated cells was determined by qRT-PCR, and whether APS affected MG63 cells through regulation of miR-133a was determined. Finally, the activation of c-Jun N-terminal protein kinase (JNK) pathway was detected. We found that APS treatment suppressed the viability, proliferation, migration, and invasion of MG63 cells, as well as induced cell apoptosis. Moreover, APS enhanced the expression of miR-133a in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced MG63 cell proliferation, migration and invasion inhibition, as well as cell apoptosis. Furthermore, APS inactivated JNK pathway in MG63 cells. Knockdown of miR-133a reversed the APS treatment-induced inactivation of JNK pathway in MG63 cells. To conclude, APS repressed proliferation, migration, and invasion while induced apoptosis of OS MG63 cells by up-regulating miR-133a and then inactivating JNK pathway.

Identification of miRNA profiling in prediction of tumor recurrence and progress and bioinformatics analysis for patients with primary esophageal cancer: Study based on TCGA database

OBJECT

This study focused on the identification of prognostic miRNAs for the prediction of tumor recurrence and progress in esophageal cancer.

METHODS

MiRNA profiling and clinical characteristics of esophageal cancer patients was downloaded from the TCGA database. Univariate analysis was performed to select potential prognostic miRNAs and covariates. LASSO based logistic regression was conducted to identify the prognostic miRNAs given covariates. Bioinformatics analysis including gene ontology, disease ontology and pathway enrichment analysis were performed. A nomogram was generated based on multivariate logistic regression to illustrate the association between the identified miRNAs and the risk of tumor recurrence and progress.

RESULTS

A total of 1881 miRNAs and 10 clinical characteristics were obtained from TCGA database. 18 miRNAs were finally identified in which 6 miRNAs were identified for the first time to be associated with the tumor recurrence and progress of esophageal cancer given covariates. Bioinformatics analysis suggested that the identified miRNAs were associated with the tumor recurrence and progress of esophageal cancer. The association between identified miRNAs and risk of tumor recurrence and progress were presented in a nomogram.

CONCLUSION

The 6 newly identified miRNAs may be potential biomarkers for the prediction of tumor recurrence and progress of esophageal cancer.

MicroRNA-539 promotes osteoblast proliferation and differentiation and osteoclast apoptosis through the AXNA-dependent Wnt signaling pathway in osteoporotic rats

This study aims to explore the effects of miR-539 on osteoblast proliferation and differentiation and osteoclast apoptosis in a rat model of osteoporosis, and its mechanism involving the regulation of the AXIN1-mediated wingless-Int (Wnt) signaling pathway. A rat model of osteoporosis was successfully established by ovariectomy. With osteoblasts and osteoclasts of rats not receiving ovariectomy in the sham group as control, those of osteoporotic rats were treated with miR-539 inhibitor, miR-539 mimic, and AXIN1 shRNA. The expression of miR-53, AXIN1, the Wnt pathway related-genes, apoptosis related-genes, and osteogenic markers were measured by RT-qPCR and Western blot analysis, respectively. Alkaline phosphatase (ALP) activity in osteoblast and tartrate-resistant acid phosphatase (TRAP) activity in osteoclasts were determined after cell transfection. Osteoblast and osteoclast viability was assayed by CCK-8 assay. Cell cycle and apoptosis of osteoblasts and osteoclasts were detected by flow cytometry. Lastly, alizarin red S staining was used to detect mineralized nodules of osteoblasts. Firstly, we determined that miR-539 was down-regulated in osteoblast and osteoclast of osteoporotic rats and AXIN1 was negatively regulated by miR-539. Additionally, overexpression of miR-539 increased the expressions of β-catenin, LEF1, c-myc, cyclin D1, RUNX2, BGP, BMP-2 in osteoblast as well as β-catenin, RhoA, caspase-3, and Bcl-2 in osteoclasts. Finally, overexpression of miR-539 elevated ALP activity, proliferation, and mineralized nodules in osteoblast and osteoclast apoptosis, with reduced TRAP activity in osteoclasts. Our results demonstrate that miR-539 promotes osteoblast proliferation and differentiation as well as osteoclast apoptosis through the AXIN1-dependent Wnt signaling pathway in osteoporotic rats.

MicroRNA-539 inhibits colorectal cancer progression by directly targeting SOX4

Colorectal cancer (CRC) is the third most prevalent cancer and the fourth most common cause of cancer-associated mortality in males and females globally. Aberrant expression of microRNA-539 (miR-539) has been reported in multiple types of cancer. However, miR-539 expression, function and underlying mechanisms have not been clearly elucidated in CRC. In the present study, miR-539 expression was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in CRC tissues and cell lines. The effects of miR-539 on CRC cells were further examined in in vitro studies. In addition, the direct targets of miR-539 in CRC were investigated using bioinformatics, luciferase reporter assays, RT-qPCR and western blotting. miR-539 was revealed to be significantly downregulated in CRC cell lines and tissues. Decreased miR-539 expression was associated with lymph node metastasis and tumor-node-metastasis stage in patients with CRC. Functional assays revealed that the rescue of miR-539 expression attenuated CRC cell proliferation and invasion in vitro. Additionally, SRY-box 4 (SOX4) was validated as a direct target gene of miR-539 in CRC. Furthermore, SOX4 was revealed to be upregulated in CRC tissues at the mRNA and protein level. A significant negative correlation between miR-539 and SOX4 mRNA expression levels was observed in CRC tissues. Furthermore, upregulation of SOX4 partially restored the tumor suppressive effects of miR-539 on CRC cell proliferation and invasion. Taken together, this suggests that miR-539 may serve tumor-suppressive functions in CRC during the process of malignant transformation, by directly targeting SOX4. miR-539/SOX4-based targeted therapy may represent a potential novel treatment for patients with CRC.

Surgical outcome and clinicopathological characteristics of emergency presentation elective cases of colorectal cancer

INTRODUCTION

The aim of this study was to evaluate the significance of clinicopathological characteristics of colorectal cancer patients undergoing emergency and elective surgery.

MATERIAL AND METHODS

In total, 116 tumors from patients treated surgically for colorectal cancer at four hospitals in Tehran between 2008 and 2013 were analyzed in the current study.

RESULTS

Our findings revealed that the emergency cases were significantly more likely to have an advanced TNM stage (p = 0.027) and histologic grade (p = 0.01) compared with the elective patients. Furthermore, the nature of surgery was significantly associated with vascular and perineural invasion (p = 0.021; p = 0.001). We also evaluated the association of gender, age, and tumor location with the nature of surgical presentation. However, no association was found between these parameters and the nature of surgery. Emergency was also correlated with greater length of hospital stay and higher rate of admission to the intensive care unit. The mortality rate was 20% in emergency cases, while patients with elective surgery had 5.63% perioperative mortality (p = 0.001). The emergency patients had a higher rate of mortality.

CONCLUSIONS

Our data indicated that colorectal cancer patients undergoing emergency surgery showed an advanced stage. The emergency patients had a higher rate of mortality than elective cases.

Identification of the miRNA-mRNA regulatory network of small cell osteosarcoma based on RNA-seq

Small cell osteosarcoma (SCO) is a rare subtype of osteosarcoma characterized by highly aggressive progression and a poor prognosis. The miRNA and mRNA expression profiles of peripheral blood mononuclear cells (PBMCs) were obtained in 3 patients with SCO and 10 healthy individuals using high-throughput RNA-sequencing. We identified 37 dysregulated miRNAs and 1636 dysregulated mRNAs in patients with SCO compared to the healthy controls. Specifically, the 37 dysregulated miRNAs consisted of 27 up-regulated miRNAs and 10 down-regulated miRNAs; the 1636 dysregulated mRNAs consisted of 555 up-regulated mRNAs and 1081 down-regulated mRNAs. The target-genes of miRNAs were predicted, and 1334 negative correlations between miRNAs and mRNAs were used to construct an miRNA-mRNA regulatory network. Dysregulated genes were significantly enriched in pathways related to cancer, mTOR signaling and cell cycle signaling. Specifically, hsa-miR-26b-5p, hsa-miR-221-3p and hsa-miR-125b-2-3p were significantly dysregulated miRNAs and exhibited a high degree of connectivity with target genes. Overall, the expression of dysregulated genes in tumor tissues and peripheral blood samples of patients with SCO measured by quantitative real-time polymerase chain reaction corroborated with our bioinformatics analyses based on the expression profiles of PBMCs from patients with SCO. Thus, hsa-miR-26b-5p, hsa-miR-221-3p and hsa-miR-125b-2-3p may be involved in SCO tumorigenesis.

MicroRNA‑539 inhibits the proliferation and invasion of bladder cancer cells by regulating IGF‑1R

Bladder cancer is the most frequent malignancy of the urinary tract and the seventh most common cancer worldwide. The abnormal expression of microRNAs has been frequently observed in various types of human cancers, including bladder cancer. In addition, an increasing body of evidence has demonstrated that microRNAs are potential targets for cancer diagnosis, treatments and prognosis. The aim of the present study was to investigate the expression patterns and potential roles of microRNA‑539 (miR‑539) in bladder cancer and its underlying mechanism. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect miR‑539 expression in the bladder cancer tissues and cell lines. Following transfection, MTT and cell invasion assays were used to investigate the effects of miR‑539 overexpression or IGF1R underexpression on bladder cancer cell proliferation and invasion. Bioinformatics analysis, a luciferase reporter assay, RT‑qPCR and western blot analysis were utilized to determine the potential targets of miR‑539 in bladder cancer. The results revealed that miR‑539 levels were relatively decreased in bladder cancer tissues and cell lines when compared with those observed in the matched adjacent normal bladder tissues and normal bladder epithelial cell line. miR‑539 expression was associated with the tumor stage and lymph node metastasis of patients with bladder cancer. In addition, the expression of miR‑539 suppressed bladder cancer cell proliferation and invasion. Insulin like growth factor 1 receptor (IGF‑1R) was identified as a direct target of miR‑539, and miR‑539 was also observed to regulate the protein kinase B and extracellular signal‑regulated kinases signaling pathways. IGF‑1R was markedly upregulated in bladder cancer tissues and negatively associated with miR‑539 expression levels. Furthermore, IGF‑1R knockdown in bladder cancer cells significantly inhibited cell proliferation and invasion. To the best of our knowledge, these results demonstrated for the first time that miR‑539 may act as a tumor suppressor and serve important roles in tumorigenesis and progression of bladder cancer. Thus, miR‑539/IGF‑1R may be a potential therapeutic target for the treatment of bladder cancer.

MiR-422a targets MAPKK6 and regulates cell growth and apoptosis in colorectal cancer cells

The important role of miR-422a in tumor has been reported in several studies. Recent research discovered that the expression of miR-422a was significantly decreased in colorectal cancer tissues, providing miR-422a as a tumor suppressor in CRC. However, the concrete mechanism of miR-422a regulating CRC cell is still unclear. In this study, we demonstrated that miR-422a could inhibit CRC cell growth and promote cell apoptosis via in vitro analyses. Moreover, computational methods were adopted to identify the targets of miR-422a. We found MAPKK6 was the direct target of miR-422a. Consequently, we further elucidated that miR-422a inhibited CRC cell growth and induced cell apoptosis by inhibiting p38/MAPK pathway. Besides that, we established the tumor xenograft model using nude mice and the inhibitory effects on tumor volumes and weights by miR-422a mimic transfection were also detected. Taken together, these findings demonstrated miR-422a exerted anti-cancer activities on CRC, which could be potentially used for CRC prognosis prediction and treatment.

MiR-539 inhibits proliferation and migration of triple-negative breast cancer cells by down-regulating LAMA4 expression

Background

Recent studies have shown that laminin subunit alpha 4 (LAMA4) plays an important role in carcinogenesis. However, its molecular biological function in triple-negative breast cancer (TNBC) has not been entirely clarified. This study investigated the expression of LAMA4 in TNBC and its effect on cell proliferation, migration and invasion. Furthermore, we also identified the potential miRNA directly targeting LAMA4.

Methods

Western blot, Real-time quantitative PCR (qPCR) and immunohistochemical staining (IHC) were used to detect the expression of LAMA4 in TNBC. The effects of LAMA4 on TNBC cell proliferation, migration and invasion were also explored in vitro. The potential miRNA that targets LAMA4 was determined by dual luciferase reporter assay and verified by qPCR and western blot analysis.

Results

Our study showed LAMA4 mRNA (p = 0.001) and protein (p = 0.005) expression in TNBC tissue samples were elevated compared with adjacent normal tissue samples, and LAMA4 was mainly expressed in the cytoplasm of breast carcinoma cells. Knockdown of LAMA4 inhibited TNBC cell proliferation, migration and invasion in vitro. Moreover, further study revealed that LAMA4 was a putative target of miR-539, and miR-539 negatively regulated LAMA4 expression by directly targeting its 3′-UTR.

Conclusions

Our study suggested that miR-539 suppressed the expression of LAMA4. LAMA4 plays an important role in tumor progression and may be an important target in treatment of TNBC.

Utility of miR‑133a‑3p as a diagnostic indicator for hepatocellular carcinoma: An investigation combined with GEO, TCGA, meta‑analysis and bioinformatics

Increasing evidence has demonstrated that microRNA (miR)‑133a‑3p is an important regulator of hepatocellular carcinoma (HCC). In the present study, the diagnostic role of miR‑133a‑3p in HCC, and the potential functional pathways, were both explored based on publicly available data. Eligible microarray datasets were collected from NCBI Gene Expression Omnibus (GEO) database and ArrayExpress database. The data related to HCC and matched adjacent normal tissues were also downloaded from The Cancer Genome Atlas (TCGA). Published studies reporting the association between miR‑133a‑3p expression and HCC were reviewed from multiple databases. By combining the data derived from three sources (GEO, TCGA and published studies), the authors analyzed the comprehensive relationship between miR‑133a‑3p expression and clinicopathological features of HCC. Eventually, putative targets of miR‑133a‑3p in HCC were selected for further bioinformatics prediction. A total of eight published microarray datasets were gathered, and the pooled results demonstrated that the expression of miR‑133a‑3p in the tumor group was lower than that in normal groups [standardized mean difference (SMD)=‑0.54; 95% confidence interval (CI), ‑0.74 to ‑0.35; P<0.001]. Consistently, the level of miR‑133a‑1 in HCC was reduced markedly compared to normal tissues (P<0.001) based on TCGA data, and the AUC value of low miR‑133a‑1 expression for HCC diagnosis was 0.670 (P<0.001). Furthermore, the combined SMD of all datasets (GEO, TCGA and literature) suggested that significant difference was observed between the HCC group and the normal control group, and lower miR‑133a‑3p expression in HCC group was noted (SMD=‑0.69; 95% CI, ‑1.10 to ‑0.29; P=0.001). In addition, the authors discovered five key genes of the calcium signaling pathway (NOS1, ADRA1A, ADRA1B, ADRA1D and TBXA2R) that may probably be targeted by miR‑133a‑3p in HCC. The study reveals that miR‑133a‑3p may function as a tumor suppressor in HCC. The prospective novel pathways and key genes of miR‑133a‑3p could offer potential biomarkers for HCC; however, the predictions require further confirmation.

Long non-coding RNA LOC100129148 functions as an oncogene in human nasopharyngeal carcinoma by targeting miR-539-5p

Emerging studies have shown that long noncoding RNAs (lncRNAs) play critical roles in carcinogenesis and progression, including human nasopharyngeal carcinoma (NPC). The correlation between lncRNAs expression and NPC development has not been well identified in the recent literature. Recently, high-through put analysis reveals that LOC100129148 is highly expressed in NPC. However, whether the aberrant expression of LOC100129148 in NPC is corrected with tumorigenesis or prognosis has not been investigated. Herein, we identified that LOC100129148 was up-regulated in NPC tissues and cell lines, and higher expression of LOC100129148 resulted in a markedly poorer survival time. Over-expressed LOC100129148 favored, but silenced LOC100129148 hampered cell proliferation in NPC cells. Additionally, LOC100129148 enhanced the KLF12 expression through functioning as a competitive 'sponge' for miR-539-5p. Thus, our study reports a novel mechanism underlying NPC carcinogenesis, and provides a potential novel diagnosis and treatment biomarker for NPC.

Investigation of clinicopathological parameters in emergency colorectal cancer surgery: a study of 67 patients

INTRODUCTION

The aim of the present study was to establish, having adjusted for case mix, the size of the differences in postoperative mortality and 5-year survival between patients presenting as an emergency with evidence of obstruction and perforation and the association of clinicopathological factors with mortality (bivariate analyses).

MATERIAL AND METHODS

The study included 67 patients who presented with colorectal cancer (CRC) between 2009 and 2013 in Iran. The mean age of the patients was 59.7 years. Of the 67 patients, 37 (55.22%) were male and 30 (44.77%) were female. Certain parameters that correlated with CRC and surgical treatment were investigated.

RESULTS

Our results showed that 46 (68.65%) patients had obstruction, while perforation was observed in 21 (31.34%) cases. Among the patients with obstruction, obstruction of the right colon was observed in 29 (43.28%) cases. There was no significant difference in mortality rate between right and left colonic obstruction. Based on the bivariate analyses, our findings showed that death of patients was significantly related to tumor grade (p = 0.02) and TNM staging (p = 0.026), but no association was found between other parameters and death, including age, sex, and tumor site.

CONCLUSIONS

Compared with patients who undergo elective surgery for colon cancer, those who present as an emergency with evidence of obstruction or perforation have higher postoperative mortality rates and poorer cancer-specific survival. Also, colorectal cancer patients with emergency surgery showed aggressive histopathology and an advanced stage.

Genetic and epigenetic drivers of neuroendocrine tumours (NET)

Neuroendocrine tumours (NET) of the gastrointestinal tract and the lung are a rare and heterogeneous group of tumours. The molecular characterization and the clinical classification of these tumours have been evolving slowly and show differences according to organs of origin. Novel technologies such as next-generation sequencing revealed new molecular aspects of NET over the last years. Notably, whole-exome/genome sequencing (WES/WGS) approaches underlined the very low mutation rate of well-differentiated NET of all organs compared to other malignancies, while the engagement of epigenetic changes in driving NET evolution is emerging. Indeed, mutations in genes encoding for proteins directly involved in chromatin remodelling, such as DAXX and ATRX are a frequent event in NET. Epigenetic changes are reversible and targetable; therefore, an attractive target for treatment. The discovery of the mechanisms underlying the epigenetic changes and the implication on gene and miRNA expression in the different subgroups of NET may represent a crucial change in the diagnosis of this disease, reveal new therapy targets and identify predictive markers. Molecular profiles derived from omics data including DNA mutation, methylation, gene and miRNA expression have already shown promising results in distinguishing clinically and molecularly different subtypes of NET. In this review, we recapitulate the major genetic and epigenetic characteristics of pancreatic, lung and small intestinal NET and the affected pathways. We also discuss potential epigenetic mechanisms leading to NET development.

miR-539 inhibits FSCN1 expression and suppresses hepatocellular carcinoma migration and invasion

Increasing evidence indicates that the dysregulation of miRNAs that act as tumor suppressors or oncogenes is involved in tumorigenesis. However, the role of miR-539 in hepatocellular carcinoma (HCC) has not been well investigated. Quantitative RT-PCR (qRT-PCR), proliferation assay, colony formation assay, migration and invasion assays, western blotting, and xenograft tumor growth models were performed to assess the expression levels and functions of miR-539 in HCC. Luciferase reporter assays, qRT-PCR, western blotting, and immunohistochemistry were used to identify and verify the targets of miR-539. miR-539 was significantly downregulated in HCC cell lines and tissue samples. Ectopic expression of miR-539 inhibited cell viability, proliferation, migration, and invasion in vitro and suppressed xenograft tumor growth in vivo. Fascin homologue 1 (FSCN1) was verified as a direct target of miR-539, and overexpression of FSCN1 promoted HCC cell migration and invasion. miR-539 acts as a novel tumor suppressor in the development and progression of HCC by targeting FSCN1, providing new insight into the mechanisms of HCC carcinogenesis and suggesting that miR-539 may be a therapeutic target.

Prognostic value of decreased microRNA-133a in solid cancers: a meta-analysis

OBJECTIVE

Increasing evidence indicates that the decreased expression of microRNA-133a (miR-133a) may be correlated with poor survival for cancer patients. Thus, we performed this meta-analysis to evaluate the prognostic value of decreased miR-133a in solid cancers.

METHODS

Eligible studies were gathered by searching on PubMed, Web of Science, and Embase. Using the STATA 12.0 software, the pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) for total and subgroup analyses were calculated to investigate the possible correlation between decreased miR-133a and overall survival (OS) of patients with cancer.

RESULTS

Ten studies were enrolled in this meta-analysis. The pooled result showed that decreased expression of miR-133a predicted poor OS in solid cancer patients (HR =1.62, 95% CI: 1.16-2.24, P=0.004). Compared with the total pooled HR, further analyses indicated that the subgroups of digestive system neoplasms (HR =1.73, 95% CI: 1.20-2.51, P=0.003), frozen tissue preservation (HR =1.89, 95% CI: 1.41-2.53, P<0.001), and multivariate analysis (HR =2.07, 95% CI: 1.42-3.02, P<0.001) exhibited stronger connection between decreased miR-133a expression and OS outcome.

CONCLUSION

This meta-analysis suggested that decreased miR-133a was associated with poor OS in patients with solid cancer. Because of the data in our study are limited, additional studies are required to verify the poor prognosis of decreased miR-133a in solid tumors.

Extensive miRNA expression analysis in craniopharyngiomas

PURPOSE

Craniopharyngiomas are benign tumors of the sellar or parasellar regions. They arise from the remnants of Rathke's pouch and are considered a "developmental disease." microRNAs are short non-coding RNAs that play a key regulatory role in the control of expression of entire gene networks. We performed an extensive analysis of miRNAs in craniopharyngiomas aiming to identify a miRNA expression signature that might aid in the prognosis of disease progression and outcome.

METHODS

Thirty-seven craniopharyngioma samples from twenty-three patients, ten age-matched controls from autopsy, and ten infant controls from the developing pituitary from autopsy were evaluated for the expression of 754 miRNAs using TaqMan® Low Density Arrays (TLDAs) v2.0 (Applied Biosystems, Foster City, CA).

RESULTS

Among the most differentially expressed miRNAs, downregulation of miR-132 appears to be a marker of aggressiveness and also plays a role in epithelial-mesenchymal transition.

CONCLUSIONS

This is the first time that an extensive study of miRNA expression has been performed in craniopharyngiomas. Further research needs to be performed to investigate the potential role of miR-132 in the development and progression of craniopharyngiomas, and its value as a prognostic marker of aggressiveness.

Upregulation of cyclin-dependent kinase 7 and matrix metalloproteinase-14 expression contribute to metastatic properties of gastric cancer

The aim of this study was to evaluate the protein and mRNA expressions of matrix metalloproteinase-14 (MMP14) and CDK7 in gastric cancer (GC) tissues. Upregulation of MMP14 mRNA level was observed in GC tissues when compared with the matched normal tissues (mean ± SD: 3.92 ± 1.15 vs. 1.35 ± 0.81, P < 0.001). This study indicated that mRNA levels of CDK7 were statistically overexpressed in GC when compared with matched normal tissues (4.12 ± 0.84 vs. 1.43 ± 0.71, P < 0.001). The protein levels of MMP14 were found to be increased in GC (60.41%; P < 0.001). The expression of CDK7 was higher in GC tissues than matched normal tissues (70.83; P < 0.001). We found that high MMP14 expression was related to advanced TNM stage (P = 0.004), tumor grade (P = 0.002), and lymph node metastasis (P = 0.015), but no association with other clinical variables (P > 0.05). In addition, high expression of CDK7 was significantly linked to advanced TNM stage (P = 0.001), pathological grade (P = 0.012), and presence of lymph node metastasis (P = 0.009), while no correlation between CDK7 expression and other clinical variables, such as age and gender, distance metastasis. The patients with high expression of MMP14 and CDK7 exhibited worse survival time than those with higher levels. Cox multivariate regression analysis clearly showed that high expression of MMP14 and CDK7 was independent prognostic factors for overall survival in patients with GC. Taken together, these results indicated the overexpression of above markers in the progression and the tumorigenesis of GC and overall patient survival. © 2016 IUBMB Life, 68(10):799-805, 2016.

miR-422a is an independent prognostic factor and functions as a potential tumor suppressor in colorectal cancer

AIM: To determine the expression of miR-422a in colorectal cancer (CRC) tissues and to further explore the prognostic value and function of miR-422a in CRC carcinogenesis.

METHODS: miR-422a expression was analyzed in 102 CRC tissues and paired normal mucosa adjacent to carcinoma by quantitative real-time PCR. The relationship of miR-422a expression with clinicopathological parameters was also analyzed. Kaplan-Meier analysis and Cox multivariate analysis were performed to estimate the potential role of miR-422a. Cell proliferation, migration, and invasion were used for in vitro functional analysis of miR-422a.

RESULTS: The levels of miR-422a were dramatically reduced in CRC tissues compared with normal mucosa (P < 0.05), and significantly correlated with local invasion (P = 0.004) and lymph node metastasis (P < 0.001). Kaplan-Meier survival and Cox regression multivariate analyses revealed that miR-422a expression (HR = 0.568, P = 0.015) and clinical TNM stage (HR = 2.942, P = 0.003) were independent prognostic factors for overall survival in CRC patients. Furthermore, in vitro experiments showed that overexpression of miR-422a inhibited the proliferation, migration, and invasion of SW480 and HT-29 cells.

CONCLUSION: Down-regulation of miR-422a may serve as an independent prognosis factor in CRC. MiR-422a functions as a tumor suppressor and regulates progression of CRC.

The plasma miR-125a, miR-361 and miR-133a are promising novel biomarkers for Late-Onset Hypogonadism

Circulating miRNAs have been shown to serve as diagnostic/prognostic biomarkers in cancers and other diseases. However, the role of plasma miRNAs in Late-onset hypogonadism (LOH) diagnosis is still unknown. Using Illumina HiSeq2000 sequencing at discovery phase, and then two-step validated by reverse transcriptase polymerase chain reaction (RT-PCR) assays in verification phases. We verified that the expression levels of miR-125a-5p, miR-361-5p and miR-133a-3p were significantly altered in LOH group compared to the control group. The area under the receiver operating characteristic (ROC) curve (AUC) is 0.682, 0.698 and 0.765, respectively. The combination of three miRNAs showed a larger AUC (0.835) that was more efficient for the diagnosis of LOH. Among three miRNAs, miR-133a-3p had the best diagnostic value for LOH with 68.2% sensitivity and 77.3% specificity. Regression analyses show that miR-133a-3p level was negatively associated with the ageing males’ symptoms (AMS) scale. However, miR-361-5p level was positively associated with serum testosterone concentrations. In summary, plasma miRNAs are differentially expressed between LOH and healthy controls. We validated three miRNAs that could act as novel biomarkers for diagnosis of LOH. These miRNAs may be involved in the development of LOH. However, further large and functional studies are warranted to confirm our findings.