Overexpression of miR-664 is associated with enhanced osteosarcoma cell migration and invasion ability via targeting SOX7

Diagnostic plasma small extracellular vesicles miRNA signatures for pancreatic cancer using machine learning methods

BACKGROUND

Identifying biomarkers may lead to easier detection and a better understanding of pathogenesis of pancreatic ductal adenocarcinoma (PDAC).

METHODS

Plasma small extracellular vesicles (sEV) from 106 participants, including 20 healthy controls (HC), 12 chronic pancreatitis (CP) patients, 12 benign pancreatic tumour (BPT) patients, and 58 PDAC patients, were profiled for microRNA (miRNA) sequencing. Three machine learning methods were applied to establish and evaluate the diagnostic model.

RESULTS

The plasma sEV miRNA diagnostic signature (d-signature) selected using the three machine learning methods could distinguish PDAC patients from non-PDAC individuals, HC, and benign pancreatic disease (BPD, CP plus BPT) both in training and validation cohort. Combining the d-signature with carbohydrate antigen 19-9 (CA19-9) performed better than with each model alone. Plasma sEV miR-664a-3p was selected by all methods and used to predict PDAC diagnosis with high accuracy combined with CA19-9. Plasma sEV miR-664a-3p was significantly positively associated with the presence of vascular invasion, lower surgery ratio, and poor differentiation. MiR-664a-3p was mainly distributed in the PDAC cancer stroma, including fibers and vessels, and was accompanied by VEGFA expression. Overexpression of miR-664a-3p could promote the epithelial-mesenchymal transition (EMT) and angiogenesis.

CONCLUSION

In conclusion, our study demonstrated the potential utility of the sEV-miRNA d-signature in the diagnosis of PDAC via machine learning methods. A novel sEV biomarker, miR-664a-3p, was identified for the diagnosis of PDAC. It can also potentially promote angiogenesis and metastasis, provide insight into PDAC pathogenesis, and reveal novel regulators of this disease.

Salvianolic acid A improves nerve regeneration and repairs nerve defects in rats with brain injury by downregulating miR-212-3p-mediated SOX7

This study was to probe the protective effects and mechanisms of salvianolic acid A (SAA) on cerebral ischemia-reperfusion injury (CIRI). The middle cerebral artery occlusion model (MCAO) was established in rats. Rats' behavior, neurological deficits, brain injury, inflammation, and apoptosis in the brain tissue were evaluated. The inflammatory response and apoptosis of PC12 cells induced by oxygen glucose deprivation/reperfusion (OGD/R) were detected. SAA-mediated changes in miR-212-3p, SOX7, and Wnt/β-catenin pathway were determined, and the targeting relationship between miR-212-3p and SOX7 was clarified. SAA alleviated the neurological deficits and brain injury of MCAO rats and inhibited the inflammatory response and apoptosis of OGD/R-conditioned PC-12 cells. SAA upregulated miR-212-3p, Wnt3a, and β-catenin, whereas inhibited SOX7 levels. Silencing miR-212-3p counteracted the protective effect of SAA in the context of CIRI. SOX7 was a target protein of miR-212-3p. Silencing SOX7 based on SAA and miR-212-3p knockdown suppressed OGD/R-induced inflammation and apoptosis and increased Wnt3a and β-catenin levels in PC12 cells. SAA can improve the brain and nervous system injury caused by cerebral ischemia-reperfusion by upregulating miR-212-3p, thereby inhibiting SOX7 and activating the Wnt/βcatenin signaling pathway.

miRNome expression analysis in canine diffuse large B-cell lymphoma

Introduction

Lymphoma is a common canine cancer with translational relevance to human disease. Diffuse large B-cell lymphoma (DLBCL) is the most frequent subtype, contributing to almost fifty percent of clinically recognized lymphoma cases. Identifying new biomarkers capable of early diagnosis and monitoring DLBCL is crucial for enhancing remission rates. This research seeks to advance our knowledge of the molecular biology of DLBCL by analyzing the expression of microRNAs, which regulate gene expression by negatively impacting gene expression via targeted RNA degradation or translational repression. The stability and accessibility of microRNAs make them appropriate biomarkers for the diagnosis, prognosis, and monitoring of diseases.

Methods

We extracted and sequenced microRNAs from ten fresh-frozen lymph node tissue samples (six DLBCL and four non-neoplastic).

Results

Small RNA sequencing data analysis revealed 35 differently expressed miRNAs (DEMs) compared to controls. RT-qPCR confirmed that 23/35 DEMs in DLBCL were significantly upregulated (n = 14) or downregulated (n = 9). Statistical significance was determined by comparing each miRNA's average expression fold-change (2-Cq) between the DLCBL and healthy groups by applying the unpaired parametric Welch's 2-sample t-test and false discovery rate (FDR). The predicted target genes of the DEMs were mainly enriched in the PI3K-Akt-MAPK pathway.

Discussion

Our data point to the potential value of miRNA signatures as diagnostic biomarkers and serve as a guideline for subsequent experimental studies to determine the targets and functions of these altered miRNAs in canine DLBCL.

MicroRNA-664a-3p inhibits the proliferation of ovarian granulosa cells in polycystic ovary syndrome and promotes apoptosis by targeting BCL2A1

Background

To investigate whether micro ribonucleic acid-664a-3p (miR-664a-3p) targeting BCL2A1 affects the proliferation and apoptosis of ovarian granulosa cells.

Methods

Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-664a-3p in granulosa cells, granular tumor cell lines (KGN), and normal ovarian epithelial cell lines (IOSE80) in the polycystic ovary syndrome (PCOS) group and the control group. After overexpressing miR-664a-3p or inhibiting its expression in KGN cells, qRT-PCR and Western blotting were used to detect the messenger RNA (mRNA) and protein levels of related genes. At the same time, a cell counting kit-8 (CCK-8) and flow cytometer were used to detect cell proliferation and apoptosis. The TargetScan website was used to predict the potential binding sites of miR-664a-3p and B-cell lymphoma 2-related protein A1 (BCL2A1), which was further verified by qRT-PCR, Western blotting, and the luciferase reporter gene method.

Results

The expression of miR-664a-3p was significantly decreased in both PCOS tissues and KGN cells (both P<0.05), and the overexpression of miR-664a-3p inhibited the proliferation of KGN cells and induced their apoptosis. Moreover, our results confirmed that miR-664a-3p directly targets BCL2A1 (P<0.05), and the inhibitory effect of miR-664a-3p on KGN cells was reversed by BCL2A1 overexpression (both P<0.05). The up-regulation of BCL2A1 promotes cell proliferation and reduces cell apoptosis by the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway (both P<0.05).

Conclusions

The up-regulation of miR-664a-3p inhibits the proliferation of KGN cells and increases apoptosis by down-regulating the expression of BCL2A1 and blocking the MAPK/ERK signaling pathway.

SOX7 suppresses endothelial-to-mesenchymal transitions by enhancing VE-cadherin expression during outflow tract development

The endothelial-to-mesenchymal transition (EndMT) is a critical process that occurs during the development of the outflow tract (OFT). Malformations of the OFT can lead to the occurrence of conotruncal defect (CTD). SOX7 duplication has been reported in patients with congenital CTD, but its specific role in OFT development remains poorly understood. To decipher this, histological analysis showed that SRY-related HMG-box 7 (SOX7) was regionally expressed in the endocardial endothelial cells and in the mesenchymal cells of the OFT, where EndMT occurs. Experiments, using in vitro collagen gel culture system, revealed that SOX7 was a negative regulator of EndMT that inhibited endocardial cell (EC) migration and resulted in decreased number of mesenchymal cells. Forced expression of SOX7 in endothelial cells blocked further migration and improved the expression of the adhesion protein vascular endothelial (VE)-cadherin (VE-cadherin). Moreover, a VE-cadherin knockdown could partly reverse the SOX7-mediated repression of cell migration. Luciferase and electrophoretic mobility shift assay (EMSA) demonstrated that SOX7 up-regulated VE-cadherin by directly binding to the gene's promoter in endothelial cells. The coding exons and splicing regions of the SOX7 gene were also scanned in the 536 sporadic CTD patients and in 300 unaffected controls, which revealed four heterozygous SOX7 mutations. Luciferase assays revealed that two SOX7 variants weakened the transactivation of the VE-cadherin promoter. In conclusion, SOX7 inhibited EndMT during OFT development by directly up-regulating the endothelial-specific adhesion molecule VE-cadherin. SOX7 mutations can lead to impaired EndMT by regulating VE-cadherin, which may give rise to the molecular mechanisms associated with SOX7 in CTD pathogenesis.

Long non-coding RNA NPBWR1-2 affects the development of ovarian cancer via multiple microRNAs

Ovarian cancer has a high incidence rate and mortality in gynaecologic malignancies. Epithelial ovarian cancer (EOC) accounts for >95% of ovarian cancer cases. Most of the patients with EOC are difficult to diagnose in early stage. The aim of the present study was to compare the long non-coding (lnc)RNA expression profiles of five ovarian cancer cell lines (IGROV1, A2780, SKOV3, ES2, and Hey) and an ovarian epithelial cell line (IOSE80) in order to identify differentially expressed lncRNAs and their associated microRNAs (miRNAs). The expression profiles of lncRNAs and mRNAs in these cell lines were determined by microarray gene analysis and reverse transcription-quantitative PCR. lncRNA neuropeptides B and W receptor 1–2 (NPBWR1-2) overexpression was induced in the SKOV3 cell line. Cell viability, proliferation, migration, invasion and apoptosis were evaluated using MTT, colony-formation, Transwell and flow cytometry assays, respectively. The microarray results indicated that several lncRNAs were differentially expressed in the five ovarian cancer cell lines compared with the normal ovarian epithelial cell line. Compared with IOSE80, lncRNA NPBWR1-2 was downregulated by more than two-fold in all five ovarian cancer cell lines. Moreover, NPBWR1-2 overexpression in the SKOV3 cell line decreased cell viability, inhibited proliferation, migration and invasion, and promoted apoptosis compared with the control cells. A total of 20 miRNAs, which are involved in tumorigenesis and development, were predicted to be associated with NPBWR1-2 by bioinformatics analysis. The results of the present study suggest that lncRNA NPBWR1-2 affects the occurrence and development of ovarian cancer via multiple miRNAs, providing a theoretical basis for the development of novel clinical treatments.

The prognostic role of CD133 expression in patients with osteosarcoma

Osteosarcoma (OS), a malignant bone tumor, mainly occurs in adolescents. Cluster of differentiation 133 (CD133) is one of the most common tumor stem cell biomarkers. The prognostic significance of CD133 in OS has been reported, while the conclusions of these study were inconsistent. This study was conducted to investigate the association between CD133 expression and OS. We performed a search using several database including NCBI PubMed, Springer, CNKI, Web of Science and Wanfang for relevant papers about the prognostic value of CD133 on OS published before October 19, 2019. Pooled odds ratio (OR) and 95% CI were used to evaluate the outcomes. Seven reports including 498 OS patients were used for evaluating the association between CD133 positive expression and OS clinicopathological features. CD133 positive expression was not related to the age, gender, tumor size, tumor location and pathological type of OS. The expression of CD133 was significantly associated with high ennecking stage of OS (OR 9.67, 95% CI 5.56-16.80, P < 0.05) and OS local recurrence (OR 3.02, 95% CI 1.84-4.94, P < 0.05). In addition, the expressions of CD133 predict metastasis (OR 7.64, 95% CI 4.93-11.85, P < 0.05). Moreover, this study indicated that CD133 expression was correlated to lower 5-year overall survival in OS with the pooled OR of 5.85 (95% CI 3.30-10.37, P < 0.05). Our reported shown that positive expression of CD133 is significantly correlated with ennecking stage, local recurrence, metastasis and low 5-year overall survival rate of OS patients.

The role of fibroblast activation protein in progression and development of osteosarcoma cells

To investigate the expression levels of fibroblast activation protein (FAP) in human osteosarcoma tissues and its possible correlations with clinical pathological characteristics of patients with osteosarcoma, and to explore the potential effects of FAP on progression and development of osteosarcoma. Immunohistochemistry (IHC) assay was initially performed to detect the expression levels of FAP in 66 tumor tissues and adjacent non-tumor tissues. Patients were sequentially divided into two groups based on different expression levels of FAP. The correlations between the expression levels of FAP and the clinical pathological characteristics were investigated, and the role of FAP in proliferation, migration, and invasion of osteosarcoma cells was assessed via colony formation, MTT, wound healing, and transwell assays, respectively. The possible effects of FAP on tumor growth and metastasis were evaluated in vivo. We further attempted to reveal the underlying mechanism of FAP involved in tumor growth through bioinformatics and IHC assays. High expression levels of FAP were noted in human osteosarcoma tissues. It also was unveiled that FAP was significantly associated with the tumor size (P = 0.005*) and clinical stage (P = 0.017*). Our data further confirmed that knockdown of FAP remarkably blocked proliferation, migration, and invasion of osteosarcoma cells in vitro, and suppressed tumor growth and metastasis in mice via AKT signaling pathway. The possible role of FAP in progression and development of osteosarcoma could be figured out. Our data may be helpful to develop a novel therapeutic target for the treatment of osteosarcoma.

lncRNA FLVCR-AS1 promotes osteosarcoma growth by targeting miR381-3p/CCND1

Purpose

This article reports on FLVCR-AS1 effects on osteosarcoma (OS) growth.

Methods

Tumor tissue and adjacent normal tissue of 48 OS patients were collected. HOS and 143B cells were transfected. Gene expression was examined with qRT-PCR and Western blot. CCK8 assays and cell cloning was performed to measure cell proliferation. Cell cycle and apoptosis were assessed. Luciferase-reporter gene assays and RNA pull-down tests were used to detect targeting relationships between genes.

Results

Prominently higher FLVCR-AS1 expression was found in OS tissue and cells, and was associated with poor prognosis (P<0.05, P<0.01, or P<0.001). Compared with the siCtrl group, 143B and HOS cells of the siFLVCR-AS1 group had significantly lower OD₄₅₀ values and clone numbers and obviously higher percentages of cells in the G₁ phase and apoptosis (P<0.01 or P<0.001). miR381-3p expression was directly inhibited by FLVCR-AS1, and CCND1 expression was directly suppressed by miR381-3p. Compared with the FLVCR-AS1 group, 143B cells of the FLVCR-AS1⁺ miR381-3p mimic group and FLVCR-AS1⁺ siCCND1 group showed remarkably lower OD₄₅₀ values and clone numbers obviously higher apoptosis and percentage of cells in the G₁ phase (P<0.05, P<0.01, or P<0.001).

Conclusion

FLVCR-AS1 promoted OS growth by upregulating CCND1 expression via downregulation of miR381-3p.

Novel role of sex-determining region Y-box 7 (SOX7) in tumor biology and cardiovascular developmental biology

The sex-determining region Y-box 7 (Sox7) is an important member of the SOX F family, which is characterized by a high-mobility-group DNA-binding domain. Previous studies have demonstrated the role of SOX7 in cardiovascular development. SOX7 expression could be detected in normal adult tissues. Furthermore, the expression levels of SOX7 were different in different tumors. Most studies showed the downregulation of SOX7 in tumors, while some studies reported its upregulation in tumors. In this review, we first summarized the upstream regulators (including transcription factors, microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and some exogenous regulators) and downstream molecules (including factors in the Wnt/β-catenin signaling pathway and some other signaling pathways) of SOX7. Then, the roles of SOX7 in multiple tumors were presented. Finally, the significance of divergent SOX7 expression during cardiovascular development was briefly discussed. The information compiled in this study characterized SOX7 during tumorigenesis and cardiovascular development, which should facilitate the design of future research and promote SOX7 as a therapeutic target.

MicroRNA-664 suppresses the growth of cervical cancer cells via targeting c-Kit

Background

Cervical cancer is the second most common malignant cancer in women worldwide. Evidence indicated that miR-664 was significantly downregulated in cervical cancer. However, the mechanisms by which miR-664 regulates the tumorigenesis of cervical cancer remain unclear. Thus, this study aimed to investigate the role of miR-664 in cervical cancer.

Methods

Quantitative reverse transcription polymerase chain reaction was used to detect the level of miR-664 in tumor tissues and cell line. The dual luciferase reporter system assay and Western blotting were used to explore the interaction of miR-664 and c-Kit in cervical cancer.

Results

The expression of miR-664 in patients with cervical cancer was dramatically decreased compared with that in adjacent tissues. MiR-664 mimics significantly inhibited proliferation in SiHa cells via inducing apoptosis. In addition, miR-664 mimics induced apoptosis in SiHa cells via increasing the expressions of Bax and active caspase 3 and decreasing the level of Bcl-2. Moreover, dual-luciferase assay showed that c-Kit was the directly binding target of miR-664 in SiHa cells; overexpression of miR-664 downregulated the expression of c-Kit. Meanwhile, upregulation of miR-664 significantly decreased the levels of c-Myc and Cyclin D in cells. Furthermore, miR-664 markedly inhibited tumor growth of cervical cancer in xenograft.

Conclusion

Our data indicated that miR-664 exerted antitumor effects on SiHa cells by directly targeting c-Kit in vitro and in vivo. Therefore, miR-664 might be a potential therapeutic target for the treatment of patients with cervical cancer.

MicroRNA-664 functions as an oncogene in cutaneous squamous cell carcinomas (cSCC) via suppressing interferon regulatory factor 2

BACKGROUND

Aberrant expression of microRNA-664 was involved in tumor growth and metastasis of various cancers. The specific role of miR-664 in cutaneous squamous cell carcinoma (cSCC) is yet to be elucidated.

OBJECTIVE

The present study aimed to investigate the molecular mechanisms underpinning of cSCC development and provide translational insights for future therapeutics.

METHODS

Human cSCC specimens were used to determine the miR-664 by in situhybridization and IRF2 by immunohistochemistry. To study the potential mechanisms in tumorigenesis, three cSCC cell lines including HSC-5, HSC-1 and A431 as well as BALB/C mouse tumor model was utilized.

RESULTS

We found that miR-664 was remarkably high in cSCC patient specimens and cSCC cell lines. Overexpression of miR-664 promotes tumorigenic behaviors such as increased cell proliferation, migration and invasion capacities in vitro and enhanced tumorigenicity in xenograft mouse model. Our data further identified IRF2 as a direct downstream target of miR-664. Knockdown of IRF2 reverses pro-tumorigenesis phenotype of miR-664; whereas IRF2 over-expression inhibits miR-664 tumorigenesis in cSCC. Together, it revealed miR-664 functions as an oncogene in cSCC via suppression of IRF2.

CONCLUSION

Our data demonstrates that aberrant expression of miR-664 plays a critical role in carcinogenesis of cSCC. The discovery of novel targets such as miR-664 and IRF2 will facilitate future development of therapeutic interventions.

miR-452 promotes cell metastasis and the epithelial to mesenchymal by targeting SOX7 in clear-cell renal-cell carcinoma

Clear-cell renal-cell carcinoma (ccRCC) is the most common renal cell carcinoma (RCC), representing 75%-80% of the cases of RCC, and characterized by a high recurrence rate and poor prognosis. miR-452 acts as a tumor promoter in several tumors, including ccRCC. The purpose of this study was to determine the role of miR-452 in ccRCC. miR-452 and SOX7 messenger RNA and protein levels were calculated by quantitative reverse transcription polymerase chain reaction and Western blot analysis. MTT and Transwell assays were utilized to measure proliferative and invasive abilities. The Kaplan-Meier method was used to evaluate the association between the expression of miR-452 or SOX7 and the overall survival of ccRCC patients. Our results showed that miR-452 was overexpressed in ccRCC tissues and cells, and upregulation of miR-452 predicted a poor 5-year survival in ccRCC patients. In contrast, expression of SOX7 was low and downregulation of SOX7 predicted poor prognosis in ccRCC. In addition, miR-452 promoted cell proliferation, invasion, and the EMT, while SOX7 reversed the function of miR-452 on cell proliferation and invasion in 786-O cells. In conclusion, miR-452 was shown to inhibit cell proliferation, invasion, and the EMT through SOX7 in ccRCC, and the newly identified miR-452/SOX7 axis provided novel insight into the pathogenesis of ccRCC.

miR-664a-3p functions as an oncogene by targeting Hippo pathway in the development of gastric cancer

OBJECTIVES

It has been accounted that miR-664a-3p has different functions in several malignancies; however, the precise role and underlying mechanism in gastric cancer have not been elucidated. Our study aims to explore the function of miR-664a-3p on the progression of gastric cancer (GC).

METHODS

qRT-PCR was applied to detect the expression of miR-664a-3p in GC tissues and cells. The functions of miR-664a-3p on GC in vitro were examined by cell proliferation assay, and transwell assay. Related proteins of epithelial-mesenchymal transition (EMT) and signal pathway were evaluated by Western blot and immunofluorescence analysis. The bioinformatic, dual-luciferase assay or ChIP assay were employed to identify the interaction between miR-664a-3p and its target gene or Foxp3. The effects in vivo were investigated through a mouse tumorigenicity model.

RESULTS

miR-664a-3p was frequently upregulated in GC tissues and cells. Elevated expression of miR-664a-3p significantly promoted proliferation and invasion in vitro and in vivo. MOB1A was confirmed to be a target of miR-664a-3p and restoration of MOB1A attenuated the effects of miR-664a-3p. A series of investigations indicated that miR-664a-3p contributed to EMT process and inactivated the Hippo pathway by downregulating MOB1A.

CONCLUSION

Taken together, we revealed that miR-664a-3p functions as an oncogene by targeting Hippo pathway in the development of gastric cancer.

Overexpression of miR-664 is associated with poor overall survival and accelerates cell proliferation, migration and invasion in hepatocellular carcinoma

Introduction

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. This study aimed to investigate the expression patterns of microRNA-664 (miR-664) in HCC tissues and cells, and assess its clinical significance and functional role in HCC.

Patients and methods

One hundred and thirty-four paired HCC and non-cancerous tissues were collected from patients who underwent surgery in Qianfoshan Hospital affiliated to Shandong University (Shandong, China) between 2009 and 2012. Expression of miR-664 was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Prognostic value of miR-664 in HCC was evaluated using Kaplan–Meier survival analysis and Cox regression analysis. Cell proliferation was analyzed using the CCK-8 assay, and cell migration and invasion of HCC cells was evaluated by the Transwell assay.

Results

Expression of miR-664 was significantly upregulated in HCC tissues and cells when compared with the normal controls (all P<0.05). MiR-664 expression was associated with lymph node metastasis, TNM stage and differentiation (all P<0.05) in the HCC patients. High miR-664 expression predicted poor overall survival (log-rank P=0.004) and acted as an independent prognostic factor (HR =1.945, 95% CI=1.078–3.508, P=0.027). According to cell experiments, the upregulation of miR-664 could promote, whereas the downregulation of miR-664 could inhibit proliferation, migration and invasion of HCC cells (all P<0.05). SIVA1 was predicted as a direct target gene of miR-664 in HCC.

Conclusion

All data indicated that overexpression of miR-664 is associated with poor prognosis of HCC patients, and may enhance tumor progression of HCC by targeting SIVA1. MiR-664 may be a candidate therapeutic target for HCC treatment.

MicroRNA-664 targets paired box protein 6 to inhibit the oncogenicity of pancreatic ductal adenocarcinoma

The abnormal expression of microRNAs (miRNAs or miRs) with oncogenic or tumor‑suppressive roles in pancreatic ductal adenocarcinoma (PDAC) has been widely reported in recent years, and these dysregulated miRNAs are implicated in the formation and progression of PDAC. Therefore, an investigation into the functional roles of miRNAs in PDAC may facilitate the identification of effective therapeutic targets. miRNA‑664 (miR‑664) has been found to be aberrantly expressed and to play crucial roles in several human cancer types. However, the expression pattern and functional roles of miR‑664 in the malignant capacity of PDAC have yet to be elucidated. In this study, the results revealed that miR‑664 was clearly downregulated in PDAC tissues and cell lines. The low miR‑664 expression was strongly associated with pathological T stage and lymph node metastasis of the patients with PDAC. Patients with PDAC with a low miR‑664 expression had a poorer overall survival and a worse disease‑free survival than those patients with a high miR‑664 level. Functional experiments suggested that exogenous miR‑664 expression suppressed the growth and metastasis of PDAC cells in vitro, whereas miR‑664 downregulation exerted the opposite effects. In addition, miR‑664 suppressed the tumor growth of PDAC cells in vivo. Mechanistically, paired box protein 6 (PAX6) was identified as a direct target gene of miR‑664 in PDAC cells. Furthermore, PAX6 was upregulated in PDAC tissues, and its upregulation inversely correlated with miR‑664 levels. Moreover, the silencing of PAX6 mimicked the effects of miR‑664 upregulation in PDAC cells, and the recovered expression of PAX6 eliminated the effects of miR‑664 on PDAC cells. Notably, miR‑664 could inhibit the activation of PI3K/Akt pathway in PDAC cells in vitro and in vivo. Cumulatively, these results indicate an important role of the miR‑664/PAX6 pathway in suppressing the aggressiveness of PDAC cells, suggesting that miR‑664 may be an attractive therapeutic target for the treatment of patients with this fatal disease.

Overexpression Of hsa-miR-664a-3p Is Associated With Cigarette Smoke-Induced Chronic Obstructive Pulmonary Disease Via Targeting FHL1

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is recognized as a chronic lung disease with incomplete reversible airflow limitation, but its pathophysiology was still not clear. This study aimed at investigating regulatory roles of special miRNA-mRNA axis in COPD development.

METHODS

Differentially expressed miRNAs and downstream mRNAs were screened from the Gene Expression Omnibus (GEO) dataset by using the LIMMA package in R software. Weighted Gene Co-expression Network Analysis (WGCNA) was used to construct a co-expression network for COPD. The correlation of dysregulated miRNA(s) and COPD was analyzed, and miRNAs with significant differences were validated in peripheral blood mononuclear cells (PBMCs) from COPD patients by real-time PCR. Regulatory roles of candidate miRNAs and targeted mRNAs were investigated in vitro study.

RESULTS

Thirteen modules of co-expressed miRNAs and mRNAs were constructed from a selected cohort with WGCNA. Turquoise module with 12 differentially expressed miRNAs and 120 mRNAs was significantly correlated with COPD. The expression of hsa-miR-664a-3p, an upregulated miRNA in the module, was increased both in lung tissue and PBMCs from COPD patients, whereas that targeted four and a half LIM domains 1 (FHL1) gene was decreased and positively correlated with forced expiratory volume in 1 sec (FEV1)/forced vital capacity (FVC%) (r = 0.59, p < 0.01). In vitro, luciferase activity assay revealed FHL1 as a target of hsa-miR-664a-3p and it could be directly downregulated by overexpression of hsa-miR-664a-3p. Furthermore, cigarette smoke extract could increase hsa-miR-664a-3p level and decrease FHL1 level in Beas-2B cells.

CONCLUSION

The present study validated significant upregulation of hsa-miR-664a-3p in COPD patients, and its target gene FHL1 was downregulated and positively correlated with FEV1/FVC%; both hsa-miR-664a-3p and FHL1 could be regulated by cigarette smoke extract. Results of bioinformatic analyses and expanded validation suggest that the axis from hsa-miR-664a-3p to FHL1 might play a key role in cigarette smoke-induced COPD, and the exact mechanism should be confirmed in further studies.

Expression of miR-664 and miR-184 on proliferation, apoptosis and migration of osteosarcoma cells

The expression of micro-ribonucleic acid miR-664 and miR-184 on the biological characteristics of osteosarcoma (OS) SOSP-9607 cells was investigated. Eighteen surgical specimens of OS and 18 normal tissue specimens were collected. The expression of miR-664 and miR-184 was detected via fluorescence reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The OS cell line SOSP-9607 was selected as the object of study, and miR-664 blank group, miR-664 mimic group, miR-664 inhibitor group, miR-184 blank group, miR-184 mimic group and miR-184 inhibitor group were established through transfection. Changes in apoptosis were detected via flow cytometry, the cell proliferation capacity was detected via Cell Counting Kit-8 assay, and the cell migration was observed via wound healing assay. In cancer tissues of OS patients, the relative expression of miR-664 and miR-184 was significantly higher than that in para-carcinoma tissues (P<0.05). The cell growth in miR-664 inhibitor group was obviously decreased compared with those in miR-664 blank and mimic groups (P<0.05). There were differences in the cell migration capacity among groups (P<0.01), and the cell scratch areas in miR-664 and miR-184 mimic groups were significantly decreased compared with those in miR-664 and miR-184 blank groups (P<0.05), while they were significantly increased in miR-664 and miR-184 inhibitor groups compared with those in miR-664 and miR-184 blank and mimic groups (P<0.05, P<0.01). There were differences in the apoptosis rate among groups (P<0.01) and apoptosis in miR-664 and miR-184 inhibitor groups was remarkably increased compared with those in miR-664 and miR-184 blank and mimic groups (P<0.05). Downregulating the expression of miR-664 and miR-184 may promote apoptosis, inhibit the proliferation and reduce the migration capacity of SOSP-9607 cells. Therefore, miR-664 and miR-184 may provide a theoretical basis for the target selection in clinical targeted therapy and drug development for OS.

Baicalin, the major component of traditional Chinese medicine Scutellaria baicalensis induces colon cancer cell apoptosis through inhibition of oncomiRNAs

Colorectal cancer (CRC) is among the most frequently occurring cancers worldwide. Baicalin is isolated from the roots of Scutellaria baicalensis and is its dominant flavonoid. Anticancer activity of baicalin has been evaluated in different types of cancers, especially in CRC. However, the molecular mechanisms underlying the contribution of baicalin to the treatment of CRC are still unknown. Here, we confirmed that baicalin can effectively induce and enhance apoptosis in HT-29 cells in a dose-dependent manner and suppress tumour growth in xenografted nude mice. We further performed a miRNA microarray analysis of baicalin-treated and untreated HT-29 cells. The results showed that a large number of oncomiRs, including miR-10a, miR-23a, miR-30c, miR-31, miR-151a and miR-205, were significantly suppressed in baicalin-treated HT-29 cells. Furthermore, our in vitro and in vivo studies showed that baicalin suppressed oncomiRs by reducing the expression of c-Myc. Taken together, our study shows a novel mechanism for anti-cancer action of baicalin, that it induces apoptosis in colon cancer cells and suppresses tumour growth by reducing the expression of c-Myc and oncomiRs.

SOX7 Target Genes and Their Contribution to Its Tumor Suppressive Function

SOX7 is a transcription factor and acts as a tumor suppressor, but its target genes in cancers are poorly explored. We revealed SOX7-mediated gene expression profile in breast cancer cells using microarray chips and discovered multiple altered signaling pathways. When combinatorially analyzing the microarray data with a gene array dataset from 759 breast cancer patients, we identified four genes as potential targets of SOX7 and validated them by quantitative PCR and chromatin immunoprecipitation assays. Among these four genes, we determined that SOX7-activated SPRY1 and SLIT2, and SOX7-repressed TRIB3 and MTHFD2 could all differentially contribute to SOX7-mediated tumor suppression. Overall, we identified multiple cancer-related pathways mediated by SOX7 and for the first time revealed SOX7-regulated target genes in a cancer-relevant context.

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.

Knockdown of Sox2 Inhibits OS Cells Invasion and Migration via Modulating Wnt/β-Catenin Signaling Pathway

Osteosarcoma (OS) was a prevalent malignant bone tumor which threatens people's health worldwide. Wnt/β catenin signaling pathway had been proved significant in various cancers, indicating its possible function in OS as well. Sox2, a crucial member among SOX family could regulate cells biologically. How Sox2 modulated Wnt/β catenin signaling pathway in OS remained to be discussed. The study aimed to investigate the effects of Sox2 on the invasion and migration of OS cells and the related molecular mechanisms. Twenty-four human OS and adjacent tissue samples were involved in this study. Human OS cell lines MG63 and HOS were selected for further investigation. The liposome carrier si-Sox2 which could interfere with the expression of Sox2 gene was built to transfect MG63 and HOS cells). QRT-PCR assay and western blot were utilized to analyze the expression of mRNA and proteins of Sox2. Transwell assay and wound healing assay were conducted to test the invasion and migration level of cells. The expression of GSK3, β-catenin, cyclin D1 and c-myc proteins were detected by western blot assay after transfection with si-Sox2. Compared with normal tissues and cells, the expression of Sox2 in OS tissues and cells was significantly higher. The mRNA and protein levels of Sox2 significantly decreased after transfection with si-Sox2. The invasion and migration of OS cells were down-regulated significantly through the inhibition of Sox2 by inactivating Wnt/β-catenin signaling pathway related proteins. Knockdown of Sox2 could inhibit invasion and migration of OS cells via modulating Wnt/β-catenin signaling pathway.

MicroRNA-664 Targets Insulin Receptor Substrate 1 to Suppress Cell Proliferation and Invasion in Breast Cancer

A large number of microRNAs (miRNAs) have been previously demonstrated to be dysregulated in breast cancer (BC), and alterations in miRNA expression may affect the initiation and progression of BC. This study showed that miR-664 expression was obviously reduced in BC tissues and cell lines. Resumption of the expression of miR-664 attenuated the proliferation and invasion of BC cells. The molecular mechanisms underlying the inhibitory effects of BC cell proliferation and invasion by miR-664 were also studied. Insulin receptor substrate 1 (IRS1) was identified as a novel and direct target of miR-664. In addition, siRNA-mediated silencing of IRS1 expression mimicked the suppressive effects of miR-664 overexpression in BC cells. Rescue experiments demonstrated that recovered IRS1 expression partially antagonized the inhibition of proliferation and invasion of BC cells caused by miR-664 overexpression. Thus, miR-664 may serve as a tumor suppressor in BC by directly targeting IRS1. Moreover, miR-664 downregulation in BC may contribute to the occurrence and development of BC, suggesting that miR-664 may be a novel therapeutic target for patients with BC.

MiR-664a-3p expression in patients with obstructive sleep apnea: A potential marker of atherosclerosis

The early prediction of atherosclerosis (AS) is important in the management of obstructive sleep apnea patients (OSA). MicroRNA (miRNA) plays a vital role in the evolution of OSA and AS. Its differential expression may therefore serve as a diagnostic and prognostic biomarker of AS in OSA. The aim of this study was to identify specific serum miRNAs that could serve as a novel screening signature of AS in OSA patients. The specificity and sensitivity of these miRNAs in the early diagnosis of AS in OSA patients were then determined.The 128 participants in this study underwent maximum carotid intima-media thickness (CIMT) measurements and polysomnography and were divided into 4 groups: 27 healthy volunteers with normal max-CIMT, 31 healthy volunteers with increased max-CIMT, 35 OSA patients with normal max-CIMT, and 35 OSA patients with iCIMT. MiRNA was extracted from the 12 participants' serum (3 participants each groups) and used to establish miRNA libraries for deep sequencing. A total of 116 participants were quantified by qRT- PCR. Correlations between differential expression of miRNAs and CIMT were assessed using the Spearman correlation coefficient. Our study was approved by the Ethics Committee of our hospital and was conducted in line with the Helsinki Declaration.MiR-664a-3p expression was quantified by qRT-PCR. Correlations between miR-664a-3p expression and CIMT were assessed using the Spearman correlation coefficient. The results showed that the miR-664a-3p was downregulated in the OSA, OSA with iCMIT, and nCIMT groups compared with the control group.The demonstrated potential of circulating miR-664a-3p as a noninvasive marker of AS in essential OSA patients should be confirmed in further studies.

Genome-wide miRNA response to anacardic acid in breast cancer cells

MicroRNAs are biomarkers and potential therapeutic targets for breast cancer. Anacardic acid (AnAc) is a dietary phenolic lipid that inhibits both MCF-7 estrogen receptor α (ERα) positive and MDA-MB-231 triple negative breast cancer (TNBC) cell proliferation with IC50s of 13.5 and 35 μM, respectively. To identify potential mediators of AnAc action in breast cancer, we profiled the genome-wide microRNA transcriptome (microRNAome) in these two cell lines altered by the AnAc 24:1n5 congener. Whole genome expression profiling (RNA-seq) and subsequent network analysis in MetaCore Gene Ontology (GO) algorithm was used to characterize the biological pathways altered by AnAc. In MCF-7 cells, 69 AnAc-responsive miRNAs were identified, e.g., increased let-7a and reduced miR-584. Fewer, i.e., 37 AnAc-responsive miRNAs were identified in MDA-MB-231 cells, e.g., decreased miR-23b and increased miR-1257. Only two miRNAs were increased by AnAc in both cell lines: miR-612 and miR-20b; however, opposite miRNA arm preference was noted: miR-20b-3p and miR-20b-5p were upregulated in MCF-7 and MDA-MB-231, respectively. miR-20b-5p target EFNB2 transcript levels were reduced by AnAc in MDA-MB-231 cells. AnAc reduced miR-378g that targets VIM (vimentin) and VIM mRNA transcript expression was increased in AnAc-treated MCF-7 cells, suggesting a reciprocal relationship. The top three enriched GO terms for AnAc-treated MCF-7 cells were B cell receptor signaling pathway and ribosomal large subunit biogenesis and S-adenosylmethionine metabolic process for AnAc-treated MDA-MB-231 cells. The pathways modulated by these AnAc-regulated miRNAs suggest that key nodal molecules, e.g., Cyclin D1, MYC, c-FOS, PPARγ, and SIN3, are targets of AnAc activity.

The tumor suppressor miR-124 inhibits cell proliferation and invasion by targeting B7-H3 in osteosarcoma

Our previous studies have shown that the expression level of B7 homolog 3 (B7-H3) was correlated with clinical staging and prognosis of osteosarcoma (OS) patients, and its silencing inhibited the proliferation and invasion of OS cells in vitro. However, its overexpression mechanism behind was far from elucidated. On the basis of bioinformatics and the preliminary screening data, we hypothesized that miR-124 might play an important role in OS development and as a lead candidate for modulating B7-H3 expression. In this study, we found that miR-124 was downregulated significantly in OS tumor tissue, compared to normal adjacent tissues (NATs). Lower miR-124 expression levels were associated with advanced Ennecking stage, lower tumor differentiation, and common pulmonary metastasis. The 5-year overall survival rate in the miR-124 upregulated group was 61.5 %, while with low miR-124 expression, only 11.8 % survived. Further studies in vitro showed that B7-H3 was a direct target of miR-124. Overexpression of miR-124 decreased B7-H3 mRNA and protein level and inhibited B7-H3 3'-UTR reporter activity. Treatment of OS cells with miR-124 mimics induced the inhibition of cell growth and invasion in vitro, which could be abrogated by transfected by B7-H3 expression vector. Our findings highlight the potential application of miR-124 as a novel onco-miRNA in OS, and its oncogenic effects are mediated chiefly through downregulation of B7-H3, thus suggesting a model for identifying miR-124 that can be exploited to improve the therapeutic potential efficacy of mAb targeting to B7-H3.