Upregulation of miR-572 transcriptionally suppresses SOCS1 and p21 and contributes to human ovarian cancer progression

Role of DNA methylation and non‑coding RNAs expression in pathogenesis, detection, prognosis, and therapy‑resistant ovarian carcinoma (Review)

Ovarian cancer is the deadliest gynecological cancer globally, with epithelial ovarian cancer (EOC) comprising up to 90% of cases. A molecular characterization linking the histological subtypes with tumor grade in EOC has been suggested. Variations in genetic biomarkers such as BRCA1/2, MSH2, MLH1/6, BRIP1, and RAD51C/D have been studied in EOC. In addition, molecular characteristics, including DNA methylation and RNA transcription, are being explored as potential new biomarkers for the diagnosis and prognosis of this type of neoplasia. The present review focused on the role of DNA methylation and non‑coding RNA expression in the development of ovarian carcinomas and their association with diagnosis, prognosis, and the resistance of cancer cells to radiotherapy and chemotherapy. The present review considered the transition from the DNA structure to the RNA expression in ovarian carcinoma.

Experimental Validation of miR-4443, miR-572, and miR-150-5p in Serum and Tissue of Breast Cancer Patients as a Potential Diagnostic Biomarker: A Study Based on Bioinformatics Prediction

Breast cancer is the most common invasive cancer diagnosed in females and is also the main cause of cancer-related deaths leading to more than 500,000 deaths annually. The present study aims to identify a promising panel of microRNAs (miRNAs) using bioinformatics analysis, and to clinically validate their utility for diagnosing breast cancer patients with high accuracy in a clinical setting. First, in the in silico phase of our study, using bioinformatics analysis and the data available in the GEO database, miRNAs that were increased in the interstitial fluid of the tumor tissues (differentially expressed miRNAs), were screened and their related target genes were selected. Multimir package of R software was utilized to determine the target genes of the differentially expressed miRNAs (DEMs). The biological functions of discovered genes were analyzed using Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. In order to determine the molecular mechanisms behind important signaling pathways and cellular functions, the protein-protein interaction network was built using STRING and Cytoscape software. After that, in the laboratory phase, the expression level of three candidate miRNAs on the serum samples of 26 breast cancer patients and 26 control, as well as 14 tumor tissue samples and 14 adjacent normal tissue samples, has been investigated by Real-time PCR method. Then sensitivity and specificity of candidate miRNAs were evaluated through the ROC curve analysis. After in silico analysis, we revealed that three miRNAs including miR-4443, miR-572, and miR-150-5p were highly increased in the interstitial fluid of breast cancer patients compared to breast cancer tissues. Moreover, our results revealed that the expression level of miR-4443, miR-572, and miR-150-5p were significantly decreased in the serum of breast cancer patients compare to normal controls. Also, the expression level of miR-4443 and miR-150-5p was significantly decreased in the tumor tissue compared to the adjacent non-tumor tissue. Also, ROC curve analysis showed that these three miRNAs have high sensitivity and specificity for the diagnosis of breast cancer patients. Data analysis was conducted with GraphPad Prism software. Our findings suggest the potential utility of measuring tumor-derived miRNAs in serum as an important approach for the blood-based detection of breast cancer patients. It appears that miR-4443, miR-572, and miR-150-5p may serve as promising diagnostic biomarkers with high sensitivity and specificity. However, it's important to note that further research will be needed to definitively establish the use of these miRNAs as potential biomarkers in clinical practice.

Genetic risk factors for periodontitis: a genome-wide association study using UK Biobank data

OBJECTIVES

Periodontitis is linked with many health conditions, but its genetic basis is not yet understood. This genome-wide association study (GWAS) aimed to investigate the genetic variants associated with periodontitis.

MATERIALS AND METHODS

This study utilised UK Biobank participants of European descent. Individuals were categorised as "having periodontitis" if they self-reported having 'painful gums', 'bleeding gums' or 'loose teeth' (n = 68,482), or as "controls" for those without these symptoms (n = 307,342). We conducted GWAS of this binary periodontitis phenotype using logistic regression models with PLINK2.0 adjusting for age, sex and the first 15 principal components to account for population stratification.

RESULTS

There were 376,611 participants (mean baseline age = 57 ± 7.9 SD) included in the GWAS, and four significant loci were identified: rs775476621 on chromosome 11 (Odds Ratio, OR[T]: 3.08, p = 1.01 × 10- 8), rs751014048 on chromosome 11 (OR[G]: 3.07, p = 1.04 × 10- 8), rs149922301 on chromosome 4 near gene RP11-61G19.1 (OR[A]: 1.18, p = 2.71 × 10- 8) and rs368467810 on chromosome 6 near gene HIST1H3L (OR[TTTA]: 0.96, p = 3.88 × 10- 8).

CONCLUSIONS

Within the current limitations, such as self-reported phenotype and older age of the study population, four loci were detected for periodontitis that have not previously been linked with this condition. Further exploration of the function of these loci may contribute to improved understanding of periodontitis aetiology and subsequent drug development.

CLINICAL RELEVANCE

These findings offer new targets for future research to investigate the genetic impact on periodontitis and aid the future understanding of periodontitis pathology and the disease's progression.

A microRNA Signature Identifies Patients at Risk of Barrett Esophagus Progression to Dysplasia and Cancer

BACKGROUND

Progression of Barrett esophagus (BE) to esophageal adenocarcinoma occurs among a minority of BE patients. To date, BE behavior cannot be predicted on the basis of histologic features.

AIMS

We compared BE samples that did not develop dysplasia or carcinoma upon follow-up of ≥ 7 years (BE nonprogressed [BEN]) with BE samples that developed carcinoma upon follow-up of 3 to 4 years (BE progressed [BEP]).

METHODS

The NanoString nCounter miRNA assay was used to profile 24 biopsy samples of BE, including 13 BENs and 11 BEPs. Fifteen samples were randomly selected for miRNA prediction model training; nine were randomly selected for miRNA validation.

RESULTS

Unpaired t tests with Welch's correction were performed on 800 measured miRNAs to identify the most differentially expressed miRNAs for cases of BEN and BEP. The top 12 miRNAs (P < .003) were selected for principal component analyses: miR-1278, miR-1301, miR-1304-5p, miR-517b-3p, miR-584-5p, miR-599, miR-103a-3p, miR-1197, miR-1256, miR-509-3-5p, miR-544b, miR-802. The 12-miRNA signature was first self-validated on the training dataset, resulting in 7 out of the 7 BEP samples being classified as BEP (100% sensitivity) and 7 out of the 8 BEN samples being classified as BEN (87.5% specificity). Upon validation, 4 out of the 4 BEP samples were classified as BEP (100% sensitivity) and 4 out of the 5 BEN samples were classified as BEN (80% specificity). Twenty-four samples were evaluated, and 22 cases were correctly classified. Overall accuracy was 91.67%.

CONCLUSION

Using miRNA profiling, we have identified a 12-miRNA signature able to reliably differentiate cases of BEN from BEP.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

The role of microRNA-572 in the proliferation and chemotherapeutic treatment of prostate cancer

OBJECTIVE

MicroRNAs (miRNAs) regulate prostate tumorigenesis and progression by involving different molecular pathways. In this study, we examined the role of miR-572 in prostate cancer (PCa).

METHODS

The proliferation rates of LNCaP and PC-3 PCa cells were studied using MTT assays. Transwell migration and Matrigel invasion assays were performed to evaluate cell migration and invasion, respectively. Protein expression levels were examined using western blotting. Docetaxel-induced apoptosis was evaluated by Caspase-Glo3/7 assays. The putative miR-572 binding site in the phosphatase and tensin homolog (PTEN) 3' untranslated region (3' UTR) was assessed with dual-luciferase reporter assays. Additionally, miR-572 expression levels in human PCa tissues were examined by qRT-PCR assays.

RESULTS

Upregulation of miR-572 promoted proliferation, migration, and invasion of PCa cells. Overexpression of miR-572 decreased sensitivity of PCa cells to docetaxel treatment by reducing docetaxel-induced apoptosis. MiR-572 can regulate migration and invasion in PCa cells. Furthermore, miR-572 could regulate expression of PTEN and p-AKT in PCa cells by directly binding to the PTEN 3' UTR. MiR-572 expression levels were increased in human PCa tissues and associated with PCa stage.

CONCLUSIONS

miR-572 displayed essential roles in PCa tumor growth and its expression level may be used to predict docetaxel treatment in these tumors.

Three functional polymorphisms in CCDC170 were associated with osteoporosis phenotype

MicroRNAs (miRNAs) play essential roles in regulating bone formation and homeostasis. Genomic variations within miRNA target sites may therefore be important sources of genetic differences in osteoporosis risk. The function of CCDC170 in bone biology is still unclear. To verify the function of CCDC170, we knocked down CCDC170 in cells and mice and searched for miRNA recognition sites within CCDC170 using the TargetScan, miRNASNP, and miRBase databases. In this study, our results demonstrated that CCDC170 plays an important role in the positive regulation of bone formation. MiR-153-3p, miR-374b-3p, miR-4274, miR-572 and miR-2964a-5p inhibited CCDC170 expression in an allele-specific manner by binding GWAS lead SNPs rs6932603, rs3757322 and rs3734806. These findings may improve our understanding of the association between CCDC170, miRNAs, GWAS lead SNPs, and osteoporosis pathogenesis and may provide a potential therapeutic target for osteoporosis therapy.

Summary: CCDC170 may provide a potential therapeutic target for osteoporosis therapy.

Small Non-Coding-RNA in Gynecological Malignancies

Gynecologic malignancies, which include cancers of the cervix, ovary, uterus, vulva, vagina, and fallopian tube, are among the leading causes of female mortality worldwide, with the most prevalent being endometrial, ovarian, and cervical cancer. Gynecologic malignancies are complex, heterogeneous diseases, and despite extensive research efforts, the molecular mechanisms underlying their development and pathology remain largely unclear. Currently, mechanistic and therapeutic research in cancer is largely focused on protein targets that are encoded by about 1% of the human genome. Our current understanding of 99% of the genome, which includes noncoding RNA, is limited. The discovery of tens of thousands of noncoding RNAs (ncRNAs), possessing either structural or regulatory functions, has fundamentally altered our understanding of genetics, physiology, pathophysiology, and disease treatment as they relate to gynecologic malignancies. In recent years, it has become clear that ncRNAs are relatively stable, and can serve as biomarkers for cancer diagnosis and prognosis, as well as guide therapy choices. Here we discuss the role of small non-coding RNAs, i.e., microRNAs (miRs), P-Element induced wimpy testis interacting (PIWI) RNAs (piRNAs), and tRNA-derived small RNAs in gynecological malignancies, specifically focusing on ovarian, endometrial, and cervical cancer.

ZNF674-AS1 antagonizes miR-423-3p to induce G0/G1 cell cycle arrest in non-small cell lung cancer cells

BACKGROUND

ZNF674-AS1, a recently characterized long noncoding RNA, shows prognostic significance in hepatocellular carcinoma and glioma. However, the expression and function of ZNF674-AS1 in non-small cell lung cancer (NSCLC) are unclear.

METHODS

In this work, we investigated the expression of ZNF674-AS1 in 83 pairs of NSCLC specimens and adjacent noncancerous lung tissues. The clinical significance of ZNF674-AS1 in NSCLC was analyzed. The role of ZNF674-AS1 in NSCLC growth and cell cycle progression was explored.

RESULTS

Our data show that ZNF674-AS1 expression is decreased in NSCLC compared to normal tissues. ZNF674-AS1 downregulation is significantly correlated with advanced TNM stage and decreased overall survival of NSCLC patients. Overexpression of ZNF674-AS1 inhibits NSCLC cell proliferation, colony formation, and tumorigenesis, which is accompanied by a G0/G1 cell cycle arrest. Conversely, knockdown of ZNF674-AS1 enhances the proliferation and colony formation of NSCLC cells. Biochemically, ZNF674-AS1 overexpression increases the expression of p21 through downregulation of miR-423-3p. Knockdown of p21 or overexpression of miR-423-3p blocks ZNF674-AS1-mediated growth suppression and G0/G1 cell cycle arrest. In addition, ZNF674-AS1 expression is negatively correlated with miR-423-3p in NSCLC specimens.

CONCLUSIONS

ZNF674-AS1 suppresses NSCLC growth by downregulating miR-423-3p and inducing p21. This work suggests the therapeutic potential of ZNF674-AS1 in the treatment of NSCLC.

Long Non-Coding RNA MAPK8IP1P2 Inhibits Lymphatic Metastasis of Thyroid Cancer by Activating Hippo Signaling via Sponging miR-146b-3p

The principal issue derived from thyroid cancer is its high propensity to metastasize to the lymph node. Aberrant exprssion of long non-coding RNAs have been extensively reported to be significantly correlated with lymphatic metastasis of thyroid cancer. However, the clinical significance and functional role of lncRNA-MAPK8IP1P2 in lymphatic metastasis of thyroid cancer remain unclear. Here, we reported that MAPK8IP1P2 was downregulated in thyroid cancer tissues with lymphatic metastasis. Upregulating MAPK8IP1P2 inhibited, while silencing MAPK8IP1P2 enhanced anoikis resistance in vitro and lymphatic metastasis of thyroid cancer cells in vivo. Mechanistically, MAPK8IP1P2 activated Hippo signaling by sponging miR-146b-3p to disrupt the inhibitory effect of miR-146b-3p on NF2, RASSF1, and RASSF5 expression, which further inhibited anoikis resistance and lymphatic metastasis in thyroid cancer. Importantly, miR-146b-3p mimics reversed the inhibitory effect of MAPK8IP1P2 overexpression on anoikis resistance of thyroid cancer cells. In conclusion, our findings suggest that MAPK8IP1P2 may serve as a potential biomarker to predict lymphatic metastasis in thyroid cancer, or a potential therapeutic target in lymphatic metastatic thyroid cancer.

miRNA signature associated with R-CHOP refractoriness in patients diagnosed with diffuse large B cell lymphoma

Refractoriness remains as one of the challenges in patients with lymphoma under chemotherapy, and among biological regulators in cells driving this type of response are microRNAs (miRNAs). Different genes are constantly turned on or off according to the miRNAs expression profiles affecting the drug response in patients and their stability in serum and plasma makes them potential prognostic biomarkers in several diseases. Here we described a profile of miRNAs in plasma of diffuse large B cell lymphoma (DLBCL) patients. miRNA expression arrays were carried using pre-treatment plasma samples of sixteen patients, followed by a comparison between the responder and the non-responders. After six cycles of R–CHOP treatment, twelve out of sixteen patients were clinically diagnosed with complete response while in four patients no clinical response was observed. Between these groups, a signature of fifteen differential expressed miRNAs was found. The circulating miRNAs in plasma of patients with no response were related to the drug resistance in other types of cancer, by targeting genes involved in cell proliferation and apoptosis, among other cell processes.

MicroRNA-572/hMOF/Sirt6 regulates the progression of ovarian cancer

Human males absent on the first (hMOF) is a histone acetyltransferase (HAT) and is involved in the pathogenesis of various cancers. This article aimed to reveal the potential mechanism of the miR-572/hMOF/Sirt6 axis in ovarian cancer (OC). In this study, we found that the mRNA and protein levels of hMOF and Sirt6 were abnormally down-regulated in OC tissues and cells. Further study indicated that the overexpression of hMOF increased the level of H4 histone acetylation in the Sirt6 promoter region and enhanced the ability of hMOF to bind to the Sirt6 promoter in OC cells, and repressed the proliferation of SKOV3 cells and promoted the apoptosis of SKOV3 cells via up-regulating Sirt6. Moreover, it was found that miR-572 negatively regulated hMOF luciferase activity. After the transfection of miR-572 inhibitor into SKOV3 cells, the cell proliferation was significantly repressed, while this repression was reversed after the transfection of shRNA-hMOF. Besides, the overexpression of hMOF could significantly inhibit the growth of tumors. Overall, our findings uncovered a novel regulatory pattern of hMOF in OC progression and provided new insights for relieving OC.

Exploring Specific miRNA-mRNA Axes With Relationship to Taxanes-Resistance in Breast Cancer

Breast cancer is the most prevalent type of malignancy in women worldwide. Taxanes (paclitaxel and docetaxel) are widely applied as first-line chemotherapeutic agents, while the therapeutic effect is seriously limited by the development of drug resistance. In the present study, we screened out several miRNAs dysregulated in taxanes-resistant breast cancer samples and confirmed that two miRNAs (miR-335-5p and let-7c-5p) played a major role in cell proliferation, apoptosis, and chemo-resistance. In addition, the weighted gene co-expression network analysis (WGCNA) for potential target genes of miR-335-5p and let-7c-5p identified three hub genes (CXCL9, CCR7, and SOCS1) with a positive relationship to taxanes-sensitivity. Further, target relationships between miR-335-5p and CXCL9, let-7c-5p and CCR7/SOCS1 were confirmed by dual-luciferase reporter assays. Importantly, the regulatory functions of CXCL9, CCR7, and SOCS1 on proliferation and chemoresistance were validated. In conclusion, our study shed light on clinical theragnostic relationships between miR-335-5p/CXCL9, let-7c-5p/CCR7/SOCS1 axes, and taxanes-resistance in breast cancer.

How microRNAs affect the PD-L1 and its synthetic pathway in cancer

Programmed cell death-ligand 1 (PD-L1) is a glycoprotein that is expressed on the cell surface of both hematopoietic and nonhematopoietic cells. PD-L1 play a role in the immune tolerance and protect self-tissues from immune system attack. Dysfunction of this molecule has been highlighted in the pathogenesis of tumors, autoimmunity, and infectious disorders. MicroRNAs (miRNAs) are endogenous molecules that are classified as small non-coding RNA with approximately 20-22 nucleotides (nt) length. The function of miRNAs is based on complementary interactions with target mRNA via matching completely or incompletely. The result of this function is decay of the target mRNA or preventing mRNA translation. In the past decades, several miRNAs have been discovered which play an important role in the regulation of PD-L1 in various malignancies. In this review, we discuss the effect of miRNAs on PD-L1 expression and consider the effect of miRNAs on the synthetic pathway of PD-L1, especially during cancers.

The Significance of MicroRNAs Expression in Regulation of Extracellular Matrix and Other Drug Resistant Genes in Drug Resistant Ovarian Cancer Cell Lines

Ovarian cancer rates the highest mortality among all gynecological malignancies. The main reason for high mortality is the development of drug resistance. It can be related to increased expression of drug transporters and increased expression of extracellular matrix (ECM) proteins. Our foremost aim was to exhibit alterations in the miRNA expression levels in cisplatin (CIS), paclitaxel (PAC), doxorubicin (DOX), and topotecan (TOP)-resistant variants of the W1 sensitive ovarian cancer cell line-using miRNA microarray. The second goal was to identify miRNAs responsible for the regulation of drug-resistant genes. According to our observation, alterations in the expression of 40 miRNAs were present. We could observe that, in at least one drug-resistant cell line, the expression of 21 miRNAs was upregulated and that of 19 miRNAs was downregulated. We identified target genes for 22 miRNAs. Target analysis showed that miRNA regulates key genes responsible for drug resistance. Among others, we observed regulation of the ATP-binding cassette subfamily B member 1 gene (ABCB1) in the paclitaxel-resistant cell line by miR-363 and regulation of the collagen type III alpha 1 chain gene (COL3A1) in the topotekan-resistant cell line by miR-29a.

Ectopic Expression of miR-532-3p Suppresses Bone Metastasis of Prostate Cancer Cells via Inactivating NF-κB Signaling

miR-532-3p is a widely documented microRNA (miRNA) involved in multifaceted processes of cancer tumorigenesis and metastasis. However, the clinical significance and biological functions of miR-532-3p in bone metastasis of prostate cancer (PCa) remain largely unknown. Herein, we report that miR-532-3p was downregulated in PCa tissues with bone metastasis, and downexpression of miR-532-3p was significantly associated with Gleason grade and serum prostate-specific antigen (PSA) levels and predicted poor bone metastasis-free survival in PCa patients. Upregulating miR-532-3p inhibited invasion and migration abilities of PCa cells in vitro, while silencing miR-532-3p yielded an opposite effect on invasion and migration abilities of PCa cells. Importantly, upregulating miR-532-3p repressed bone metastasis of PCa cells in vivo. Our results further demonstrated that overexpression of miR-532-3p inhibited activation of nuclear facto κB (NF-κB) signaling via simultaneously targeting tumor necrosis factor receptor-associated factor 1 (TRAF1), TRAF2, and TRAF4, which further promoted invasion, migration, and bone metastasis of PCa cells. Therefore, our findings reveal a novel mechanism contributing to the sustained activity of NF-κB signaling underlying the bone metastasis of PCa.

miR-424-5p Promotes Anoikis Resistance and Lung Metastasis by Inactivating Hippo Signaling in Thyroid Cancer

miR-424-5p has been widely identified to function as an oncomiR in multiple human cancer types. However, the biological function of miR-424-5p in distant metastasis of thyroid cancer, as well as the underlying mechanism, remains not clarified yet. In the current study, miR-424-5p expression was elucidated in 10 paired fresh thyroid cancer tissues and the thyroid cancer dataset from The Cancer Genome Atlas (TCGA). Lung metastasis colonization models in vivo and functional assays in vitro were used to determine the role of miR-424-5p in thyroid cancer. Bioinformatics analysis, western blot, luciferase reporter, and immunofluorescence assays were applied to identify the potential targets and underlying mechanism involved in the functional role of miR-424-5p in lung metastasis of thyroid cancer. Here, we reported that miR-424-5p was upregulated in thyroid cancer, and overexpression of miR-424-5p significantly correlated with distant metastasis of thyroid cancer. Upregulating miR-424-5p promoted, whereas silencing miR-424-5p inhibited, anoikis resistance in vitro and lung metastasis in vivo. Mechanistic investigation further revealed that miR-424-5p promoted anoikis resistance and lung metastasis by inactivating Hippo signaling via simultaneously targeting WWC1, SAV1, and LAST2. Therefore, our results support the idea that miR-424-5p may serve as a potential therapeutic target in lung metastasis of thyroid cancer.

Amorphous silica nanoparticles induce tumorigenesis via regulating ATP5H/SOD1-related oxidative stress, oxidative phosphorylation and EIF4G2/PABPC1-associated translational initiation

Background

Recent studies indicate amorphous silica nanoparticles (SiNPs), one of the widely applied nanomaterials, have potential toxicity in humans and induces cell malignant transformation. However, its carcinogenic mechanisms remain poorly understood. This study’s purpose was to investigate the underlying toxic mechanisms of amorphous SiNPs on human lung epithelial cells model by using microarray data.

Methods

Microarray dataset GSE82062 was collected from Gene Expression Omnibus database, including three repeats of Beas-2B exposed to amorphous SiNPs for 40 passages and three repeats of passage-matched control Beas-2B cells. Differentially expressed genes (DEGs) were identified using linear models for microarray data method. Protein–protein interaction (PPI) network was constructed using data from the STRING database followed by module analysis. The miRwalk2 database was used to predict the underlying target genes of differentially miRNAs. Function enrichment analysis was performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID) online tool.

Results

A total of 323 genes were identified as DEGs, including 280 downregulated (containing 12 pre-miRNAs) and 43 upregulated genes (containing 29 pre-miRNAs). Function enrichment indicated these genes were involved in translational initiation (i.e., eukaryotic translation initiation factor 4 gamma 2 (EIF4G2), poly (A) binding protein cytoplasmic 1 (PABPC1)), response to reactive oxygen species (i.e., superoxide dismutase 1 (SOD1)) and oxidative phosphorylation (i.e., ATP5H). PABPC1 (degree = 15), ATP5H (degree = 11) and SOD1 (degree = 8)] were proved to be hub genes after PPI-module analyses. ATP5H/SOD1 and EIF4G2/PABPC1 were overlapped with the target genes of differentially expressed pre-miR-3648/572/661 and pre-miR-4521.

Conclusions

Amorphous SiNPs may induce tumorigenesis via influencing ATP5H/SOD1-related oxidative stress, oxidative phosphorylation and EIF4G2/PABPC1-associated translational initiation which may be regulated by miR-3648/572/661 and miR-4521, respectively.

Diagnostic Value of Circulating microRNAs for In-Stent Restenosis in Patients with Lower Extremity Arterial Occlusive Disease

In-stent restenosis (ISR) is still a major cause of failure of endovascular stenting treatment in patients with lower extremity arterial occlusive disease (LEAOD). Sensitive and reliable biomarkers for early diagnosis to predict ISR should be considered. This study was conducted to explore the diagnostic value of microRNA in predicting ISR in patients with LEAOD after endovascular stenting treatment. From March 2014 to July 2016, 208 patients (170 males and 38 females) with LEAOD undergoing interventional treatment were enrolled in this research. Patients were divided into the restenosis and non-restenosis groups according to routine postoperative angiography. Circulating microRNAs expression were detected in 208 participants, including 78 ISR patients, 68 non-ISR patients and 62 healthy volunteers. We selected 6 microRNAs from microarray screening as candidates for further testing via qRT-PCR. A receiver operating characteristic (ROC) curve was generated to assess the diagnostic value of circulating microRNAs in predicting ISR for LEAOD patients. The results showed that circulating microRNA-320a and microRNA-572 in patients with ISR (n = 78) had significantly higher expression levels than it from non-ISR and healthy volunteers. By receiver operating characteristic curve analysis, the sensitivity was 82.1% and the specificity was 63.8% for microRNA-320a; the sensitivity was 69.2% and the specificity was 68.9% for microRNA-572, and the AUC was 0.766 and 0.690 for detection of ISR, respectively. Furthermore, 78 patients with ISR had significantly higher circulating expression levels of microRNA-3937 and microRNA-642a-3p and lower circulating expression levels of microRNA-4669 and microRNA-3138 compared with 68 non-ISR patients and 62 healthy volunteers, but they have no significant difference. We found that differential circulating microRNA expression in patients after stenting with ISR, and the data indicate that circulating microRNA-320a and microRNA-572 have promising value in diagnosing ISR in patients with LEAOD.

MicroRNAs as prognostic markers in prostate cancer

BACKGROUND

Prostate cancer (PCa) is the most commonly diagnosed malignancy in men who are especially over the age of 50 years in the western countries. Currently used therapeutic modalities mostly fail to give positive clinical outcomes and nearly 30% of the PCa patients eventually develop clinical recurrence. Therefore, understanding the underlying mechanisms of PCa progression is of paramount importance to help determining the course of disease. In this study, we aimed at profiling the differentially expressed microRNAs in recurrent PCa samples.

METHODS

We profiled the microRNA expression of 20 recurrent and 20 non-recurrent PCa patients with microRNA microarray, and validated the differential expression of significantly deregulated microRNAs in 40 recurrent and 39 non-recurrent PCa specimens using quantitative reverse-transcription PCR (qRT-PCR). Data were statistically analyzed using two-sided Student's t-test, Pearson Correlation test, Receiver operating characteristic (ROC) analysis.

RESULTS

Our results demonstrated that a total of 682 probes were significantly deregulated in recurrent versus non-recurrent PCa specimen comparison. Among those, we confirmed the significant downregulation of miR-424 and upregulation of miR-572 with further qRT-PCR analysis in a larger sample set. Further ROC analysis showed that these microRNAs have enough power to distinguish recurrent specimens from non-recurrent ones on their own.

CONCLUSIONS

Here, we report that differential expression of miR-424 and miR-572 in recurrent PCa specimens can serve as novel biomarkers for prediction of PCa progression.

Role of microRNA-150-5p/SRCIN1 axis in the progression of breast cancer

In China, breast cancer is the most commonly occurring cancer in women. MicroRNAs (miRs) are a group of endogenous small non-coding RNAs, which serve a role in many biological processes through the regulation of target genes. In the current study, miR-150-5p expression was significantly up-regulated in breast cancer tissues and cell lines. To investigate the cellular function and underlying molecular mechanism of miR-150-5p in breast cancer, TargetScan7.2 was used to identify miR-150-5p target genes. SRC kinase signaling inhibitor 1 (SRCIN1) was identified as a direct target gene of miR-150-5p and the current study demonstrated that SRCIN1 was negatively regulated by miR-150-5p in breast cancer cells. Furthermore, SRCIN1 expression was significantly down-regulated in breast cancer tissues and cell lines. Taken together, these results demonstrated that there was a negative association between miR-150-5p and SRCIN1 in breast cancer. The CCK-8 and Transwell assays were used to examine breast cancer cell viability, invasion and migration ability. The current study demonstrated that over-expression of miR-150-5p enhanced breast cancer cell proliferation, invasion and migration. In addition, miR-150-5p over-expression increased the expression of mesenchymal cell markers (vimentin, N-cadherin and β-catenin) and decreased the expression of epithelial cell markers (E-cadherin and zonula occludens-1). By contrast, miR-150-5p knockdown inhibited breast cancer cell viability, invasion and migration. Additionally, miR-150-5p knockdown decreased the expression of mesenchymal cell markers and increased the expression of epithelial cell markers. Taken together, these results suggest that the miR-150-5p/SRCIN1 axis may be a potential target in the treatment of breast cancer.

miR-582-3p and miR-582-5p Suppress Prostate Cancer Metastasis to Bone by Repressing TGF-β Signaling

A number of studies have reported that aberrant expression of microRNAs (miRNAs) closely correlates with the bone metastasis of prostate cancer (PCa). However, clinical significance and functional roles of both strands of a single miRNA in bone metastasis of PCa remain undefined. Here, we reported that miR-582-3p and miR-582-5p expression were simultaneously reduced in bone metastatic PCa tissues compared with non-bone metastatic PCa tissues. Downexpression of miR-582-3p and miR-582-5p strongly and positively correlated with advanced clinicopathological characteristics and shorter bone metastasis-free survival in PCa patients. Upregulating miR-582-3p and miR-582-5p inhibited invasion and migration abilities of PCa cells in vitro, as well as repressed bone metastasis in vivo. Our results further revealed that miR-582-3p and miR-582-5p attenuated bone metastasis of PCa via inhibiting transforming growth factor β (TGF-β) signaling by simultaneously targeting several components of TGF-β signaling, including SMAD2, SMAD4, TGF-β receptor I (TGFBRI), and TGFBRII. Moreover, deletion contributes to miR-582-3p and miR-582-5p downexpression in PCa tissues. Finally, clinical negative correlations of miR-582-3p and miR-582-5p with SMAD2, SMAD4, TGFBRI, and TGFBRII were demonstrated in PCa tissues. Thus, our findings explore a novel tumor-suppressive miRNA with its both strands implicated in bone metastasis of PCa, suggesting its potential therapeutic value in treatment of PCa bone metastasis.

Knockdown of miR-572 suppresses cell proliferation and promotes apoptosis in renal cell carcinoma cells by targeting the NF2/Hippo signaling pathway

Background: Renal cell carcinoma (RCC) is one of the most common types of cancer. miR-572 has been proposed to be implicated in a number of human cancers, including RCC. Nevertheless, the detailed functions and molecular mechanisms of miR-572 in RCC have not been well illustrated. Methods: qRT-PCR assay was used to assess the expression of miR-572 in RCC specimens and cell lines. Loss-of-function experiments were carried out to explore the effect of miR-572 on proliferation and apoptosis in 786-O cells. Predicted by TargetScan, the interaction between miR-572 and neurofibromin 2 (NF2) was explored by dual-luciferase reporter assay and western blot analysis. To investigate whether the regulatory effect of miR-572 was mediated by NF2, 786-O cells were transfected with anti-miR-572 alone, or together with si-NF2. After that, western blot assay was used to validate whethermiR-572 regulated proliferation and apoptosis of the RCC cell line through NF2/Hippo signaling. Results: miR-572 expression was upregulated in RCC specimens and cell lines, and miR-572 knockdown suppressed proliferation and enhanced apoptosis in 786-O cells. miR-572 repressed NF2 expression by binding to NF2 mRNA 3'-UTR. Moreover, the anti-miR-572-mediated regulatory effect on proliferation and apoptosis was abated by the restoration of NF2 expression in RCC cells. Furthermore, miR-572 knockdown activated NF2/Hippo signaling pathway in RCC cells. Conclusions: The regulatory effect of miR-572 on proliferation and apoptosis is mediated through modulating NF2/Hippo signaling in RCC cell lines, providing a novel potential strategy for RCC.

Downregulation of miR‑505‑3p predicts poor bone metastasis‑free survival in prostate cancer

The principal issue deriving from prostate cancer (PCa) is its propensity to metastasize to bone. To date, bone metastasis remains incurable, and therapeutic strategies are limited. Therefore, it is of paramount importance to explore predictive markers for bone metastasis of PCa. In the present study, we reported that miR-505-3p was significantly downregulated in bone metastatic PCa tissues compared with that in non-bone metastatic PCa tissues, but there was no significant difference in miR-505-3p expression between PCa and adjacent normal tissues. miR-505-3p expression was inversely associated with serum PSA levels, Gleason grade, N and M classification, and short bone metastasis-free survival in PCa patients, but had no effect on overall survival in PCa patients. Furthermore, upregulation of miR-505-3p suppressed the activity of TGF-β signaling by directly targeting downstream effectors of TGF-β signaling, SMAD2 and SMAD3, further inhibiting the invasion and migration abilities of PCa cells. Therefore, our findings unraveled a novel mechanism by which miR-505-3p inhibits bone metastasis of PCa, supporting the notion that miR-505-3p may serve as a predictive marker for bone metastasis of PCa.

The competing endogenous circular RNA ADAMTS14 suppressed hepatocellular carcinoma progression through regulating microRNA-572/regulator of calcineurin 1

Emerging evidence have discovered that circular RNAs (circRNAs) may serve as diagnostic or tumor promising biomarkers. This study aimed to investigate how circular RNA ADAMTS14 (circADAMTS14) regulates microRNA-572/ regulator of calcineurin 1(miR-572/ RCAN1) in hepatocellular carcinoma (HCC). The expression profiles of circRNA/microRNA (mRNA) between HCC tissues and paired adjacent tissues were analyzed via microarray analysis. The expressions of circADAMTS14, miR-572, and RCAN1 were measured by real-time polymerase chain reaction (PCR). The protein expression level of RCAN1 in HCC cells was detected by western blot. The viability and apoptosis levels of HCC cell lines were measured by the cell counting Kit-8 (CCK-8) assay and fluorescence-activated cell sorter. The invasiveness and migration of cells were detected based on the transwell and wound-healing assay, respectively. The dual-luciferase reporter assays were used to reveal circADAMTS14 and RCAN1 as a potential target of miR-572, which was predicted by TargetScan and miRBase. The effect of circADAMTS14 on HCC cells was demonstrated by tumor formation in nude mice in vivo. CircADAMTS14 and RCAN1 were lowly expressed in HCC clinical specimens and cell lines using microarrays and qRT-PCR, but miR-572 inversely. Our study further verified the direct interaction between circADAMTS14 and RCAN1 with miR-572 via the dual-luciferase reporter gene assay. Overexpressed circADAMTS14 and RCAN1 induced apoptosis of HCC cells and inhibited cell proliferation and invasion. But overexpressed miR-572 could decrease apoptosis of HCC cells and promote proliferation and invasion. In vivo, circADAMTS14 inhibited the tumor growth, correlated positively with the protein expression levels of RCAN1. Our results demonstrated that circADAMTS14 might suppress HCC progression through regulating miR-572/ RCAN1 as the competing endogenous RNA.

Epigenetic Crosstalk between the Tumor Microenvironment and Ovarian Cancer Cells: A Therapeutic Road Less Traveled

Metastatic dissemination of epithelial ovarian cancer (EOC) predominantly occurs through direct cell shedding from the primary tumor into the intra-abdominal cavity that is filled with malignant ascitic effusions. Facilitated by the fluid flow, cells distribute throughout the cavity, broadly seed and invade through peritoneal lining, and resume secondary tumor growth in abdominal and pelvic organs. At all steps of this unique metastatic process, cancer cells exist within a multidimensional tumor microenvironment consisting of intraperitoneally residing cancer-reprogramed fibroblasts, adipose, immune, mesenchymal stem, mesothelial, and vascular cells that exert miscellaneous bioactive molecules into malignant ascites and contribute to EOC progression and metastasis via distinct molecular mechanisms and epigenetic dysregulation. This review outlines basic epigenetic mechanisms, including DNA methylation, histone modifications, chromatin remodeling, and non-coding RNA regulators, and summarizes current knowledge on reciprocal interactions between each participant of the EOC cellular milieu and tumor cells in the context of aberrant epigenetic crosstalk. Promising research directions and potential therapeutic strategies that may encompass epigenetic tailoring as a component of complex EOC treatment are discussed.

Downregulation of miR-133a-3p promotes prostate cancer bone metastasis via activating PI3K/AKT signaling

BACKGROUND

Bone metastasis is a leading cause of morbidity and mortality in advanced prostate cancer (PCa). Downexpression of miR-133a-3p has been found to contribute to the progression, recurrence and distant metastasis in PCa. However, clinical significance of miR-133a-3p in bone metastasis of PCa, and the biological role of miR-133a-3p and its molecular mechanisms underlying bone metastasis of PCa remain unclear.

METHODS

miR-133a-3p expression was evaluated in 245 clinical PCa tissues by real-time PCR. Statistical analysis was performed to evaluate the clinical correlation between miR-133a-3p expression and clinicopathological features, and overall and bone metastasis-free survival in PCa patients. The biological roles of miR-133a-3p in the bone metastasis of PCa were investigated both in vitro and in vivo. Bioinformatics analysis, real-time PCR, western blot and luciferase reporter analysis were applied to demonstrate the relationship between miR-133a-3p and its potential targets. Western blotting and luciferase assays were examined to identify the underlying pathway involved in the anti-tumor role of miR-133a-3p. Clinical correlation of miR-133a-3p with its targets was verified in human PCa tissues.

RESULTS

miR-133a-3p expression is reduced in PCa tissues compared with the adjacent normal tissues and benign prostate lesion tissues, particularly in bone metastatic PCa tissues. Low expression of miR-133a-3p is significantly correlated with advanced clinicopathological characteristics and shorter bone metastasis-free survival in PCa patients by statistical analysis. Moreover, upregulating miR-133a-3p inhibits cancer stem cell-like phenotypes in vitro and in vivo, as well as attenuates anoikis resistance in vitro in PCa cells. Importantly, administration of agomir-133a-3p greatly suppresses the incidence of PCa bone metastasis in vivo. Our results further demonstrate that miR-133a-3p suppresses bone metastasis of PCa via inhibiting PI3K/AKT signaling by directly targeting multiple cytokine receptors, including EGFR, FGFR1, IGF1R and MET. The negative clinical correlation of miR-133a-3p with EGFR, FGFR1, IGF1R, MET and PI3K/AKT signaling activity is determined in clinical PCa tissues.

CONCLUSION

Our results unveil a novel mechanism by which miR-133a-3p inhibits bone metastasis of PCa, providing the evidence that miR-133a-3p may serve as a potential bone metastasis marker in PCa, and delivery of agomir-133a-3p may be an effective anti-bone metastasis therapeutic strategy in PCa.

Transcriptional downregulation of miR-133b by REST promotes prostate cancer metastasis to bone via activating TGF-β signaling

High avidity of bone metastasis is an important characteristic in prostate cancer (PCa). Downexpression of miR-133b has been reported to be implicated in the development, progression and recurrence in PCa. However, clinical significance and biological roles of miR-133b in bone metastasis of PCa remain unclear. Here we report that miR-133b is downregulated in PCa tissues and further decreased in bone metastatic PCa tissues. Downexpression of miR-133b positively correlates with advanced clinicopathological characteristics and shorter bone metastasis-free survival in PCa patients. Upregulating miR-133b inhibits invasion, migration in vitro and bone metastasis in vivo in PCa cells. Mechanistically, we find that miR-133b suppresses activity of TGF-β signaling via directly targeting TGF-β receptor I and II, which further inhibits bone metastasis of PCa cells. Our results further reveal that overexpression of REST contributes to miR-133b downexpression via transcriptional repression in PCa tissues. Importantly, silencing miR-133b enhances invasion and migration abilities in vitro and bone metastasis ability in vivo in REST-silenced PCa cells. The clinical correlation of miR-133b with TGFBRI, TGFBRII, REST and TGF-β signaling activity is verified in PCa tissues. Therefore, our results uncover a novel mechanism of miR-133b downexpression that REST transcriptionally inhibits miR-133b expression in PCa cells, and meanwhile support the notion that administration of miR-133b may serve as a rational regimen in the treatment of PCa bone metastasis.

STAT3 induces colorectal carcinoma progression through a novel miR-572-MOAP-1 pathway

Purpose

Colorectal carcinoma (CRC) is among the most common causes of death. Recent studies have shown that both STAT3 and miR-572 contribute to CRC progression. STAT3 plays an important role in miRNA expression. Moreover, MOAP-1, which is a pro-apoptotic protein that induces cell death or apoptosis, has a direct correlation with miRNA. Therefore, the current study is designed to explore whether miR-572 and STAT3 are involved in a common pathway and the role of MOAP-1 in this process.

Patients and methods

The expressions of STAT3, miR-572, and MOAP-1 in human CRC tissues and multiple cell lines were estimated by qRT-PCR or Western blot. MTT, transwell migration, and invasion assays were used to assess cell growth, migration, and invasion, respectively. Dual-luciferase reporter assay was applied to examine the association between miR-572 and MOAP-1.

Results

Elevated STAT3 levels were accompanied by increased miR-572 and decreased MOAP-1 levels in primary CRC specimens and cell lines. STAT3 promoted CRC cell growth, migration, and invasion via the upregulated expression of miR-572. Subsequently, miR-572 inhibited MOAP-1 protein expression through an interaction with its 3′UTR.

Conclusion

Our study proposes a novel STAT3-miR-572-MOAP-1 pathway involved in the process of CRC progression, which might be a potential target for the development of new preventive and therapeutic approaches against human colorectal cancer.

Maintenance of cancer stemness by miR-196b-5p contributes to chemoresistance of colorectal cancer cells via activating STAT3 signaling pathway

Emerging studies indicated that cancer stem cells represent a subpopulation of cells within the tumor that is responsible for chemotherapeutic resistance. However, the underlying mechanism is still not clarified yet. Here we report that miR-196b-5p is dramatically upregulated in CRC tissues and high expression of miR-196b-5p correlates with poor survival in CRC patients. Moreover, recurrent gains (amplification) contribute to the miR-196b-5p overexpression in CRC tissues. Silencing miR-196b-5p suppresses spheroids formation ability, the fraction of SP cells, expression of stem cell factors and the mitochondrial potential, and enhances the apoptosis induced by 5-fluorouracil in CRC cells; while ectopic expression of miR-196b-5p yields an opposite effect. In addition, downregulation of miR-196b-5p resensitizes CRC cells to 5-fluorouracil in vivo. Our results further demonstrate that miR-196b-5p promotes stemness and chemoresistance of CRC cells to 5-fluorouracil via targeting negative regulators SOCS1 and SOCS3 of STAT3 signaling pathway, giving rise to activation of STAT3 signaling. Interestingly, miR-196b-5p is highly enriched in the serum exosomes of patients with CRC compared to the healthy control subjects. Thus, our results unravel a novel mechanism of miR-196b-5p implicating in the maintenance of stem cell property and chemotherapeutic resistance in CRC, offering a potential rational registry of anti-miR-196b-5p combining with conventional chemotherapy against CRC.

Downregulation of miR-374b-5p promotes chemotherapeutic resistance in pancreatic cancer by upregulating multiple anti-apoptotic proteins

Resistance to first-line chemotherapeutic drugs such as gemcitabine contributes to the poor prognosis of patients with pancreatic cancer. MicroRNAs (miRNA) regulate chemoresistance in pancreatic cancer. By analyzing the miRNA sequencing dataset of pancreatic cancer from The Cancer Genome Atlas, it was demonstrated that miR-374b-5p expression was dramatically reduced in pancreatic cancer tissues compared with adjacent normal tissues, as well as decreased in chemoresistant compared with chemosensitive pancreatic carcinoma tissues. The decreased expression of miR-374-5p was associated with poor overall and progression-free survival in patients with pancreatic cancer. Furthermore, increased expression of miR-374b-5p abrogated, while the silencing miR-374b-5p increased the chemoresistance of pancreatic cancer cells to gemcitabine in vitro. Importantly, the upregulation of miR-374b-5p ameliorated the chemoresistance of pancreatic cancer cells to gemcitabine in vivo. It was also demonstrated that miR-374b-5p targeted several anti-apoptotic proteins, including B-cell lymphoma 2, Baculoviral IAP Repeat Containing 3 and X-linked inhibitor of apoptosis in pancreatic cancer cells, which further attenuated chemo-resistance in pancreatic cancer. Therefore, the results of the current study indicate that miR-374b-5p serves as a potential diagnostic marker. It also suggests that miR-374b-5p sensitizes cells to chemotherapy and may be used in combination with chemotherapeutic agents such as gemcitabine to treat patients with pancreatic cancer.

NCAM1 is the Target of miRNA-572: Validation in the Human Oligodendroglial Cell Line

The neural cell adhesion molecule 1 (NCAM1) is a fundamental protein in cell-cell interaction and in cellular developmental processes, and its dysregulation is involved in a number of diseases including multiple sclerosis. Studies in rats suggest that the modulation of NCAM1 expression is regulated by miRNA-572, but no data are available confirming such interaction in the human system. We analyzed whether this is the case using a human oligodendroglial cell line (MO3.13). MO3.13 cells were transfected with miRNA-572 mimic and inhibitor separately; NCAM1 mRNA and protein expression levels were analyzed at different time points after transfection. Results indicated that NCAM1 expression is increased after transfection with miRNA-572 inhibitor, whereas it is decreased after transfection with the mimic (p < 0.005). The interaction between NCAM1 and miRNA-572 was subsequently confirmed in a Vero cell line that does not express NCAM1, by luciferase assay after transfection with NCAM1. These results confirm that miRNA-572 regulates NCAM1 and for the first time demonstrate that this interaction regulates NCAM1 expression in human cells. Data herein also support the hypothesis that miRNA-572 is involved in diseases associated with NCAM1 deregulation, suggesting its possible use as a biomarker in these diseases.

miR‑149‑5p promotes chemotherapeutic resistance in ovarian cancer via the inactivation of the Hippo signaling pathway

Chemotherapeutic resistance remains a critical clinical issue is responsible for treatment failure in patients with ovarian cancer. Evidence of the involvement of miRNAs in chemoresistance in ovarian cancer has been recently emerging. However, the underlying molecular links between chemoresistance and miRNAs remain largely unknown. In this study, we report that miR-149-5p expression is markedly elevated in chemoresistant ovarian cancer tissues compared with the chemosensitive ovarian cancer tissues. Furthermore, the silencing of miR-149-5p enhanced the chemosensitivity of ovarian cancer cells to cisplatin in vitro and in vivo. Conversely, the upregulation of miR-149-5p aggravated chemoresistance in ovarian cancer cells. Our results further revealed that miR-149-5p directly targeted the core kinase components of the Hippo signaling pathway, STE20-like kinase (MST)1 and protein salvador homolog 1 (SAV1), resulting in the inactivation of TEA domain (TEAD) transcription. On the whole, our findings reveal a novel mechanism of of action miR-149-5p in inducing chemotherapeutic resistance in ovarian cancer, indicating that miR-149-5p may serve as a chemotherapeutic response indicator and a potential therapeutic target in ovarian cancer.

Downregulation of miR‑19a‑3p promotes invasion, migration and bone metastasis via activating TGF‑β signaling in prostate cancer

Constitutive activation of TGF-β signaling pathway is a well-documented mechanism responsible for the bone metastasis of prostate cancer (PCa). MicroRNAs (miRNAs) have been reported to be crucial for the activation of TGF-β signaling via targeting downstream components of TGF-β signaling pathway. Here, we report that miR-19a-3p is downregulated in bone metastatic PCa tissues and cells. Upregulation of miR-19a-3p suppresses invasion, migration in vitro and inhibits bone metastasis in vivo in PCa cells. Conversely, silencing miR-19a-3p yields the opposite effect. Our results further demonstrate that miR-19a-3p inhibits invasion and migration abilities of PCa cells via targeting downstream effectors of TGF-β signaling, SMAD2 and SMAD4, resulting in the inactivation of TGF-β signaling. Therefore, our results uncover a novel mechanistic understanding of miR-19a-3p-induced suppressive role in bone metastasis of PCa, which will facilitate the development of effective cancer therapy methods against PCa.

Targeting Oncogenic Transcription Factors: Therapeutic Implications of Endogenous STAT Inhibitors

Misregulation of transcription factors, including signal transducer and activator of transcription (STAT) proteins, leads to inappropriate gene expression patterns that can promote tumor initiation and progression. Under physiologic conditions, STAT signaling is stimulus dependent and tightly regulated by endogenous inhibitors, namely, suppressor of cytokine signaling (SOCS) proteins, phosphatases, and protein inhibitor of activated STAT (PIAS) proteins. However, in tumorigenesis, STAT proteins become constitutively active and promote the expression of progrowth and prosurvival genes. Although STAT activation has been widely implicated in cancer, therapeutic STAT inhibitors are still largely absent from the clinic. This review dissects the mechanisms of action of two families of endogenous STAT inhibitors, the SOCS and PIAS families, to potentially inform the development of novel therapeutic inhibitors.

MicroRNAs in gynecological cancers: Small molecules with big implications

Gynecological cancers (GCs) are often diagnosed at advanced stages, limiting the efficacy of available therapeutic options. Thus, there remains an urgent and unmet need for innovative research for the efficient clinical management of GC patients. Research over past several years has revealed the enormous promise of miRNAs. These small non-coding RNAs can aid in the diagnosis, prognosis and therapy of all major GCs, viz., ovarian cancers, cervical cancers and endometrial cancers. Mechanistic details of the miRNAs-mediated regulation of multiple biological functions are under constant investigation, and a number of miRNAs are now believed to influence growth, proliferation, invasion, metastasis, chemoresistance and the relapse of different GCs. Modulation of tumor microenvironment by miRNAs can possibly explain some of their reported biological effects. miRNA signatures have been proposed as biomarkers for the early detection of GCs, even the various subtypes of individual GCs. miRNA signatures are also being pursued as predictors of response to therapies. This review catalogs the knowledge gained from collective studies, so as to assess the progress made so far. It is time to ponder over the knowledge gained, so that more meaningful pre-clinical and translational studies can be designed to better realize the potential that miRNAs have to offer.

Downregulation of miR-874-3p promotes chemotherapeutic resistance in colorectal cancer via inactivation of the Hippo signaling pathway

Overcoming resistance to chemotherapy is an arduous challenge in the treatment of colorectal cancer (CRC), particularly since the underlying molecular mechanisms remain obscure. In the present study, we reported that miR-874-3p was markedly downregulated in CRC tissues compared with that in adjacent normal colorectal epithelial tissues. Upregulation of miR-874-3p attenuated the chemoresistance of CRC cells to 5-fluorouracil (5-FU) in vitro and in vivo. Conversely, inhibition of miR-874-3p yielded an opposite effect. Furthermore, our results demonstrated that miR-874-3p directly inhibited the expression of transcriptional co-activators YAP and TAZ of the Hippo signaling pathway, resulting in the inactivation of the TEAD transcription. Thus, our findings clarify a novel mechanism by which miR-874-3p restores chemotherapeutic sensitivity of CRC to 5-FU, indicating that offering miR-874-3p mimics in combination with 5-FU may serve as a new therapeutic strategy to circumvent the chemoresistance in CRC.

Interaction between miR-572 and PPP2R2C, and their effects on the proliferation, migration, and invasion of nasopharyngeal carcinoma (NPC) cells

We investigated the how miR-572 regulates PPP2R2C, and studied the effects of miR-572 and PPP2R2C on proliferation and migration as well as invasion of nasopharyngeal carcinoma (NPC) cells. NPC tissues and normal tissues were collected, and the expressions of miR-572 and PPP2R2C were detected by real-time PCR. Western blot was applied to detect the expression of PPP2R2C protein. The target relationship between miR-572 and PPP2R2C was confirmed by dual luciferase reporter gene assay. MTT assay and flow cytometry were applied to investigate the viability and apoptosis levels of NPC cells. Transwell as well as wound healing assays were used, respectively, to detect the invasiveness and migration of NPC cells. MiR-572 was highly expressed in NPC tissues as well as NPC cells, and there was lower expression of PPP2R2C in NPC tissues compared with normal samples. MiR-572 could bind to the 3' UTR of PPP2R2C and decrease its expression. Over-expressed miR-572 and decreased PPP2R2C expression could both inhibit proliferation and invasion and induce apoptosis of NPC cells. Thus, miR-572 promotes the proliferation and invasion of NPC by directly down-regulating PPP2R2C.

MicroRNA expression in bone marrow-derived human multipotent Stromal cells

Background

Multipotent stromal cells (MSCs) are being studied in the field of regenerative medicine for their multi-lineage differentiation and immunoregulatory capacity. MicroRNAs (miRNAs) are short non-coding RNAs that are responsible for regulating gene expression by targeting transcripts, which can impact MSC functions such as cellular proliferation, differentiation, migration and cell death. miRNAs are expressed in MSCs; however, the impact of miRNAs on cellular functions and donor variability is not well understood. Eight MSC lines were expanded to passages 3, 5 and 7, and their miRNA expression was evaluated using microarray technology.

Results

Statistical analyses of our data revealed that 71 miRNAs out of 939 examined were expressed by this set of MSC lines at all passages and the expression of 11 miRNAs were significantly different between passages 3 and 7, while the expression of 7 miRNAs was significantly different between passages 3 and 5. The expression of these identified miRNAs was evaluated using RT-qPCR for both the first set of MSC lines (n = 6) and a second set of MSC lines (n = 7) expanded from passages 4 to 8. By RT-qPCR only 2 miRNAs, miR-638 and miR-572 were upregulated at passage 7 compared to passage 3 in the first set of MSC lines by 1.71 and 1.54 fold, respectively; and upregulated at passage 8 compared to passage 4 in the second set of MSC lines, 1.35 and 1.59 fold, respectively.

Conclusions

The expression of miR-638 and miR-572 can distinguish MSCs from two different passages of cell culture. These results may be useful in establishing critical quality attributes of MSCs and determining whether changes in these two miRNAs impact cellular functions.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-3997-7) contains supplementary material, which is available to authorized users.

miR‑150 inhibits proliferation and tumorigenicity via retarding G1/S phase transition in nasopharyngeal carcinoma

Cancer cells are characterized by a pathological manifestation of uncontrolled proliferation, which results in tumor formation. Therefore, it is necessary to improve understanding of the underlying mechanism of cell cycle control. Here, we report that miR-150 is downregulated in nasopharyngeal carcinoma tissues and cells. Upregulation of miR-150 suppresses nasopharyngeal carcinoma (NPC) cell proliferation and induces G₁/S arrest in vitro, and inhibits tumorigenesis in vivo. Conversely, silencing miR-150 yields the opposite effect. Our results further demonstrate that miR-150 retards nasopharyngeal carcinoma cell proliferation and G₁/S transition via targeting multiple cell cycle-related genes, including CCND1, CCND2, CDK2 and CCNE2. Therefore, our results uncover a novel mechanistic understanding of miR-150-mediated tumor suppression in NPC, which will facilitate the development of effective cancer therapies against nasopharyngeal carcinoma.

Identification of miRNA-mRNA crosstalk in CD4+ T cells during HIV-1 infection by integrating transcriptome analyses

BACKGROUND

HIV-1-infected long-term nonprogressors (LTNPs) are characterized by infection with HIV-1 more than 7-10 years, but keeping high CD4+ T cell counts and low viral load in the absence of antiretroviral treatment, while loss of CD4+ T cells and high viral load were observed in the most of HIV-1-infected individuals with chronic progressors (CPs) However, the mechanisms of different clinical outcomes in HIV-1 infection needs to be further resolved.

METHODS

To identify microRNAs (miRNAs) and their target genes related to distinct clinical outcomes in HIV-1 infection, we performed the integrative transcriptome analyses in two series GSE24022 and GSE6740 by GEO2R, R, TargetScan, miRDB, and Cytoscape softwares. The functional pathways of these differentially expressed miRNAs (DEMs) targeting genes were further analyzed with DAVID.

RESULTS

We identified that 7 and 19 DEMs in CD4+ T cells of LTNPs and CPs, respectively, compared with uninfected controls (UCs), but only miR-630 was higher in CPs than that in LTNPs. Further, 478 and 799 differentially expressed genes (DEGs) were identified in the group of LTNPs and CPs, respectively, compared with UCs. Compared to CPs, four hundred and twenty-four DEGs were identified in LTNPs. Functional pathway analyses revealed that a close connection with miRNA-mRNA in HIV-1 infection that DEGs were involved in response to virus and immune system process, and RIG-I-like receptor signaling pathway, whose DEMs or DEGs will be novel biomarkers for prediction of clinical outcomes and therapeutic targets for HIV-1.

CONCLUSIONS

Integrative transcriptome analyses showed that distinct transcriptional profiles in CD4+ T cells are associated with different clinical outcomes during HIV-1 infection, and we identified a circulating miR-630 with potential to predict disease progression, which is necessary to further confirm our findings in the future.

SMAR1 binds to T(C/G) repeat and inhibits tumor progression by regulating miR-371-373 cluster

Chromatin architecture and dynamics are regulated by various histone and non-histone proteins. The matrix attachment region binding proteins (MARBPs) play a central role in chromatin organization and function through numerous regulatory proteins. In the present study, we demonstrate that nuclear matrix protein SMAR1 orchestrates global gene regulation as determined by massively parallel ChIP-sequencing. The study revealed that SMAR1 binds to T(C/G) repeat and targets genes involved in diverse biological pathways. We observe that SMAR1 binds and targets distinctly different genes based on the availability of p53. Our data suggest that SMAR1 binds and regulates one of the imperative microRNA clusters in cancer and metastasis, miR-371-373. It negatively regulates miR-371-373 transcription as confirmed by SMAR1 overexpression and knockdown studies. Further, deletion studies indicate that a ~200 bp region in the miR-371-373 promoter is necessary for SMAR1 binding and transcriptional repression. Recruitment of HDAC1/mSin3A complex by SMAR1, concomitant with alteration of histone marks results in downregulation of the miRNA cluster. The regulation of miR-371-373 by SMAR1 inhibits breast cancer tumorigenesis and metastasis as determined by in vivo experiments. Overall, our study highlights the binding of SMAR1 to T(C/G) repeat and its role in cancer through miR-371-373.

Altered Expressions of miR-1238-3p, miR-494, miR-6069, and miR-139-3p in the Formation of Chronic Brucellosis

Brucellosis is a zoonotic disease that is still endemic in developing countries. Despite early diagnosis and treatment of patients, chronic infections are seen in 10–30% of patients. In this study, we aimed to investigate the immunological factors that play roles in the transition of brucellosis from acute infection into chronic infection. Here, more than 2000 miRNAs were screened in peripheral blood mononuclear cells (PBMCs) of patients with acute or chronic brucellosis and healthy controls by using miRNA array, and the results of the miRNA array were validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Four miRNAs were expressed in the chronic group but were not expressed in acute and control groups. Among these miRNAs, the expression level of miR-1238-3p was increased while miR-494, miR-6069, and miR-139-3p were decreased (p < 0.05, fold change > 2). These miRNAs have the potential to be markers for chronic cases. The differentially expressed miRNAs and their predicted target genes involved in endocytosis, regulation of actin cytoskeleton, MAPK signaling pathway, and cytokine-cytokine receptor interaction and its chemokine signaling pathway indicate their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human PBMC to clarify the mechanism of inveteracy in brucellosis.

Androgen-induced miR-135a acts as a tumor suppressor through downregulating RBAK and MMP11, and mediates resistance to androgen deprivation therapy

The main challenge in the treatment of prostate cancer (PCa) is that the majority of patients inevitably develop resistance to androgen deprivation. However, the mechanisms involved in hormone independent behavior of PCa remain unclear. In the present study, we identified androgen-induced miR-135a as a direct target of AR. Functional studies revealed that overexpression of miR-135a could significantly decrease cell proliferation and migration, and induce cell cycle arrest and apoptosis in PCa. We identified RBAK and MMP11 as direct targets of miR-135a in PCa by integrating bioinformatics analysis and experimental assays. Mechanistically, miR-135a repressed PCa migration through downregulating MMP11 and induced PCa cell cycle arrest and apoptosis by suppressing RBAK. Consistently, inverse correlations were also observed between the expression of miR-135a and RBAK or MMP11 in PCa samples. In addition, low miR-135a and high RBAK and MMP11 expression were positively correlated with PCa progression. Also, PI3K/AKT pathway was confirmed to be an upstream regulation signaling of miR-135a in androgen-independent cell lines. Accordingly, we reported a resistance mechanism to androgen deprivation therapy (ADT) mediated by miR-135a which might be downregulated by androgen depletion and/or PI3K/AKT hyperactivation, in castration-resistant prostate cancer (CRPC), thus promoting tumor progression. Taken together, miR-135a may represent a new diagnostic and therapeutic biomarker for castration-resistant PCa.

3B, a novel photosensitizer, inhibits glycolysis and inflammation via miR-155-5p and breaks the JAK/STAT3/SOCS1 feedback loop in human breast cancer cells

Compared to normal cells, most cancer cells produce ATP by glycolysis under aerobic conditions rather than via the tricarboxylic acid cycle (TCA). This study is intended to determine whether 3B, a novel photosensitizer, can inhibit glycolysis and inflammation in breast cancer cells. We showed that 3B had the ability to repress glucose consumption as well as the generation of ATP, lactate and lactate dehydrogenase. 3B-PDT not only inhibited the expression of IL-1β and IL-6 but also affected the JAK-STAT3 inflammatory pathway in vitro. The present study showed that 3B featured a significant inhibitory effect on the expression of microRNA-155-5p and SOCS1 might serve as a target gene. In vivo studies revealed that 3B inhibited tumor growth and exhibited almost no side effects. Therefore, through the anti-glycolytic effect and breakage of the JAK/STAT3/SOCS1 feedback loop via miR-155-5p, 3B may potentially serve as a potential therapeutic agent against breast cancer.

Antibiotic drug tigecycline inhibits melanoma progression and metastasis in a p21CIP1/Waf1-dependent manner

Antibiotics are common drugs with low toxicity but high effectiveness. They have been suggested to be drug candidates for cancer therapy in recent years. Here, we tried to investigate the antitumour effect of tigecycline on malignant melanoma. We showed that tigecycline dramatically inhibited cell proliferation and induced cell cycle arrest at G0/G1 phase. At the same time, tigecycline suppressed cell invasion and migration through preventing epithelial-mesenchymal transition (EMT) process. In addition, tigecycline also significantly blocked tumor growth in vivo. Expression of cell cycle-related proteins were investigated and resulted in downregulation of G1/S checkpoint proteins, such as CDK2 and Cyclin E. However, cyclin-dependent kinase inhibitor 1 (CDKN1A, p21(CIP1/Waf1)) was downregulated after tigecycline treatment, which was not conformed to its conventional function. To explain this, we overexpressed p21 in melanoma cells. We found that p21 overexpression significantly rescued tigecycline-induced cell proliferation inhibition as well as migration and invasion suppression. Taken together, our results revealed that the essential role of p21 in the inhibitory effect of tigecycline on proliferation, migration and invasion of melanoma. Tigecycline might act as a candidate therapeutic drug for treatment of patients suffering from malignant melanoma.

MicroRNA expression profiles in pediatric dysembryoplastic neuroepithelial tumors

Among noncoding RNAs, microRNAs (miRNAs) have been most extensively studied, and their biology has repeatedly been proven critical for central nervous system pathological conditions. The diagnostic value of several miRNAs was appraised in pediatric dysembryoplastic neuroepithelial tumors (DNETs) using miRNA microarrays and receiving operating characteristic curves analyses. Overall, five pediatric DNETs were studied. As controls, 17 samples were used: the FirstChoice Human Brain Reference RNA and 16 samples from deceased children who underwent autopsy and were not present with any brain malignancy. The miRNA extraction was carried out using the mirVANA miRNA Isolation Kit, while the experimental approach included miRNA microarrays covering 1211 miRNAs. Quantitative real-time polymerase chain reaction was performed to validate the expression profiles of miR-1909* and miR-3138 in all samples initially screened with miRNA microarrays. Our findings indicated that miR-3138 might act as a tumor suppressor gene when down-regulated and miR-1909* as a putative oncogenic molecule when up-regulated in pediatric DNETs compared to the control cohort. Subsequently, both miRNA signatures might serve as putative diagnostic biomarkers for pediatric DNETs.

MiR-572 prompted cell proliferation of human ovarian cancer cells by suppressing PPP2R2C expression

Ovarian cancer (OC) remains one of the most common types of malignant cancer, and the molecular mechanism underlying its proliferation is still largely unclear. It is reported that microRNAs acted as important regulators of cell proliferation by regulating its targeted gene. In this study, our result showed that miR-572 was markedly upregulated in OC cell lines and clinical tissues. Results of both gain-of-function and loss-of-function experiments revealed that upregulation of miR-572 expression dramatically promoted OC cell proliferation, whereas decreased miR-572 expression significantly reduced cell proliferation. Bioinformatics analysis and luciferase reporter assays further revealed PPP2R2C, a putative tumor suppressor as a potential target of miR-572. Moreover, silencing of PPP2R2C using small interfering RNA (siRNA) counteracted the proliferation arrest by miR-572-in in OC cells. In sum, our data provide that miR-572 promoted cell proliferation in OC by targeting PPP2R2C and might serve as a therapeutic target of OC.

Regulation of Macrophage, Dendritic Cell, and Microglial Phenotype and Function by the SOCS Proteins

Macrophages are innate immune cells of dynamic phenotype that rapidly respond to external stimuli in the microenvironment by altering their phenotype to respond to and to direct the immune response. The ability to dynamically change phenotype must be carefully regulated to prevent uncontrolled inflammatory responses and subsequently to promote resolution of inflammation. The suppressor of cytokine signaling (SOCS) proteins play a key role in regulating macrophage phenotype. In this review, we summarize research to date from mouse and human studies on the role of the SOCS proteins in determining the phenotype and function of macrophages. We will also touch on the influence of the SOCS on dendritic cell (DC) and microglial phenotype and function. The molecular mechanisms of SOCS function in macrophages and DCs are discussed, along with how dysregulation of SOCS expression or function can lead to alterations in macrophage/DC/microglial phenotype and function and to disease. Regulation of SOCS expression by microRNA is discussed. Novel therapies and unanswered questions with regard to SOCS regulation of monocyte-macrophage phenotype and function are highlighted.