MicroRNA-663 inhibits the proliferation, migration and invasion of glioblastoma cells via targeting TGF-β1

TGF-β1 and Mechanical-Stretch Induction of Lysyl-Oxidase and Matrix-Metalloproteinase Expression in Synovial Fibroblasts Requires NF-κB Pathways

The imbalance in the expression of matrix metalloproteinases (MMPs) and lysyl oxidases (LOXs) in synovial fibroblasts (SFs) caused by mechanical injury and inflammatory response prevents injured anterior cruciate ligaments (ACLs) from self-healing. However, research on the effect of growth factors on SFs on regulating the microenvironment is limited. In this study, mechanical injury and exogenous transform growth factor-β1 (TGF-β1) were employed to mimic a joint-cavity microenvironment with ACL trauma. The function of the NF-κB transcription factor was further studied. The study found that the gene expression of LOXs (except LOXL-1), MMP-1, -2, and -3 in SFs was promoted by the combination of injurious mechanical stretching and TGF-β1 and that the upregulation of MMPs was higher than that of LOXs. In addition, MMP-2 activity induced by the combination of injurious stretch and TGF-β1 was inhibited by NF-κB inhibitors such as Bay11-7082 and Bay11-7085. The findings concluded that the synovium was an important regulator of the knee joint-cavity microenvironment after ACL injury and that the NF-κB pathway mediated the regulation of MMP-2 in SFs via mechanical factors and TGF-β1.

The Role of microRNAs in Multidrug Resistance of Glioblastoma

Simple Summary

Glioblastoma (GBM) is one of the most malignant types of central nervous system tumor which accounts for more than 60% of all brain tumors in adults. Owing to poor prognosis and drug resistance of most GBM, it is urged to further develop the diagnosis and treatment strategies. The aim of this article is to highlight the roles of some functional microRNAs in the diagnosis and treatment of drug-resistant GBM. Besides, we suggest effective treatment strategies based on the expression profiles of these effective miRNAs to provide an alternative solution to deal with this cancer.

Abstract

Glioblastoma (GBM) is an aggressive brain tumor that develops from neuroglial stem cells and represents a highly heterogeneous group of neoplasms. These tumors are predominantly correlated with a dismal prognosis and poor quality of life. In spite of major advances in developing novel and effective therapeutic strategies for patients with glioblastoma, multidrug resistance (MDR) is considered to be the major reason for treatment failure. Several mechanisms contribute to MDR in GBM, including upregulation of MDR transporters, alterations in the metabolism of drugs, dysregulation of apoptosis, defects in DNA repair, cancer stem cells, and epithelial–mesenchymal transition. MicroRNAs (miRNAs) are a large class of endogenous RNAs that participate in various cell events, including the mechanisms causing MDR in glioblastoma. In this review, we discuss the role of miRNAs in the regulation of the underlying mechanisms in MDR glioblastoma which will open up new avenues of inquiry for the treatment of glioblastoma.

Upregulation of Atypical Cadherin FAT1 Promotes an Immunosuppressive Tumor Microenvironment via TGF-β

FAT atypical cadherin 1 (FAT1) promotes glioblastoma (GBM) by promoting protumorigenic inflammatory cytokine expression in tumor cells. However, tumors also have an immunosuppressive microenvironment maintained by mediators such as transforming growth factor (TGF)-β cytokines. Here, we have studied the role of FAT1 in tumor immune suppression. Our preliminary TIMER2.0 analysis of The Cancer Genome Atlas (TCGA) database revealed an inverse correlation of FAT1 expression with infiltration of tumor-inhibiting immune cells (such as monocytes and T cells) and a positive correlation with tumor-promoting immune cells [such as myeloid-derived suppressor cells (MDSCs)] in various cancers. We have analyzed the role of FAT1 in modulating the expression of TGF-β1/2 in resected human gliomas, primary glioma cultures, and other cancer cell lines (U87MG, HepG2, Panc-1, and HeLa). Positive correlations of gene expression of FAT1 and TGF-β1/2 were observed in various cancers in TCGA, Glioma Longitudinal Analysis Consortium (GLASS), and Chinese Glioma Genome Atlas (CGGA) databases. Positive expression correlations of FAT1 were also found with TGF-β1/2 and Serpine1 (downstream target) in fresh-frozen GBM samples using q-PCR. siRNA-mediated FAT1 knockdown in cancer cell lines and in primary cultures led to decreased TGF-β1/2 expression/secretion as assessed by q-PCR, Western blotting, and ELISA. There was increased chemotaxis (transmigration) of THP-1 monocytes toward siFAT1-transfected tumor cell supernatant as a consequence of decreased TGF-β1/2 secretion. Reduced TGF-β1 expression was also observed in THP-1 cultured in conditioned media from FAT1-depleted glioma cells, thus contributing to immune suppression. In U87MG cells, decreased TGF-β1 upon FAT1 knockdown was mediated by miR-663a, a known modulator. FAT1 expression was also observed to correlate positively with the expression of surrogate markers of MDSCs [programmed death ligand-1 (PD-L1), PD-L2, and interleukin (IL)-10] in glioma tumors, suggesting a potential role of FAT1 in MDSC-mediated immunosuppression. Hence, our findings elaborate contributions of FAT1 to immune evasion, where FAT1 enables an immunosuppressive microenvironment in GBM and other cancers via TGF-β1/2.

Involvement of long non-coding RNA ZNF503 antisense RNA 1 in diabetic retinopathy and its possible underlying mechanism

ZNF503 antisense RNA 1 (ZNF503-AS1) is a newly identified long non-coding RNA (lncRNA) that regulates retinal pigment epithelium differentiation. To study its role in diabetic retinopathy, we performed RT-qPCR to measure plasma ZNF503-AS1 levels of 298 diabetic patients immediately after the diagnosis, during the follow-up, and at the end of follow-up. Plasma lncRNA ZNF503-AS1 expression in 96 healthy participants was also detected by RT-qPCR. Transforming growth factor beta 1 (TGF-β1) expression after ZNF503-AS1 overexpression was detected by Western blot. Cell proliferation and apoptosis were detected by cell proliferation and apoptosis assays, respectively. We found that ZNF503-AS1 was not differentially expressed in healthy participants and diabetic patients. High plasma lncRNA ZNF503-AS1 level was correlated with a high incidence of diabetic retinopathy. Plasma lncRNA ZNF503-AS1 level was higher in patients with diabetic retinopathy than in patients with other complications (p < 0.05). ZNF503-AS1 overexpression inhibited proliferation, promoted cell apoptosis, and upregulated TGF-β1 expression (p < 0.05). We concluded that ZNF503-AS1 might participate in diabetic retinopathy by activating TGF-β signaling.

Long non-coding RNA PCED1B-AS1 promotes the proliferation of colorectal adenocarcinoma through regulating the miR-633/HOXA9 axis

Long non-coding RNA (lncRNA) PCED1B-AS1 was shown to play essential roles in human cancers, while its function in colorectal adenocarcinoma remains unclear. This study was carried out to investigate the function of PCED1B-AS1 in regulating the microRNA(miR)-633/HOXA9 axis in colorectal adenocarcinoma. The expression of PCED1B-AS1, miR-633 and HOXA9 was measured by quantitative real-time PCR (qRT-PCR) or Western blot analysis. Cell behaviors of colorectal adenocarcinoma cell lines were assessed by CCK-8, EdU, Transwell and flow cytometry assays. The interaction among PCED1B-AS1, miR-633 and HOXA9 was determined by luciferase reporter and RIP assays. Rescue experiments were performed to determine the regulatory axis in colorectal adenocarcinoma. Moreover, an animal model was established to verify the role of PCED1B-AS1. We found that PCED1B-AS1 was upregulated and miR-633 was downregulated in colorectal adenocarcinoma tissues and corresponding cell lines. Knockdown of PCED1B-AS1 inhibited cell proliferation and promoted apoptosis, while miR-633 inhibitor elevated proliferation and reduced apoptosis of cancer cell lines. In addition, overexpression of HOXA9 obviously attenuated the protective role of knockdown of PCED1B-AS1 or miR-633 mimics in colorectal adenocarcinoma progression. PCED1B-AS1 could negatively regulate the expression of HOXA9 by sponging miR-633. The in vivo experiments confirmed the role of PCED1B-AS1 and miR-633 in colorectal adenocarcinoma, as well as the regulatory relationship of this axis. Our results demonstrated that knockdown of PCED1B-AS1 inhibited the progression of colorectal adenocarcinoma by regulating the miR-633/HOXA9 axis.

MicroRNA-663 prevents monocrotaline-induced pulmonary arterial hypertension by targeting TGF-β1/smad2/3 signaling

OBJECTIVE

Pulmonary vascular remodeling due to excessive growth factor production and pulmonary artery smooth muscle cells (PASMCs) proliferation is the hallmark feature of pulmonary arterial hypertension (PAH). Recent studies suggest that miR-663 is a potent modulator for tumorigenesis and atherosclerosis. However, whether miR-663 involves in pulmonary vascular remodeling is still unclear.

METHODS AND RESULTS

By using quantitative RT-PCR, we found that miR-663 was highly expressed in normal human PASMCs. In contrast, circulating level of miR-663 dramatically reduced in PAH patients. In addition, in situ hybridization showed that expression of miR-663 was decreased in pulmonary vasculature of PAH patients. Furthermore, MTT and cell scratch-wound assay showed that transfection of miR-663 mimics significantly inhibited platelet derived growth factor (PDGF)-induced PASMCs proliferation and migration, while knockdown of miR-663 expression enhanced these effects. Mechanistically, dual-luciferase reporter assay revealed that miR-663 directly targets the 3'UTR of TGF-β1. Moreover, western blots and ELISA results showed that miR-663 decreased PDGF-induced TGF-β1 expression and secretion, which in turn suppressed the downstream smad2/3 phosphorylation and collagen I expression. Finally, intratracheal instillation of adeno-miR-663 efficiently inhibited the development of pulmonary vascular remodeling and right ventricular hypertrophy in monocrotaline (MCT)-induced PAH rat models.

CONCLUSION

These results indicate that miR-663 is a potential biomarker for PAH. MiR-663 decreases PDGF-BB-induced PASMCs proliferation and prevents pulmonary vascular remodeling and right ventricular hypertrophy in MCT-PAH by targeting TGF-β1/smad2/3 signaling. These findings suggest that miR-663 may represent as an attractive approach for the diagnosis and treatment for PAH.

BORIS/CTCFL expression activates the TGFβ signaling cascade and induces Drp1 mediated mitochondrial fission in neuroblastoma

The cancer-testis antigen CTCFL/BORIS (Brother of Regulator of Imprinted Sites) also known, as a paralog of CTCF -the "master weaver of the genome" is a key transcriptional regulator. Both CTCF and BORIS can bind to the same promoter sequence and recruit diverse proteins. BORIS is also known to be associated with actively translating ribosomes suggesting new roles of BORIS in gene expression. Various studies have attempted to elucidate the role of BORIS in different cell types for the development of targeted therapy depending on molecular signatures and genetic aberrations associated with the disease type. The current study is focused on its role in neuroblastoma. Here, we have deciphered the role of BORIS on TGFβ1 pathway which is highly affected by embryonic CTCFL expression. BORIS stabilized the SMAD3 and SMAD4 transcripts leading to prolonged TGFβ activation. Further, loss of BORIS abrogated both the canonical and non-canonical TGFβ signaling suggesting the dependency of TGFβ on BORIS. The effect on the metabolic profile of the neuroblastoma cells were analyzed with change in BORIS expression levels. Also, ectopic expression of BORIS leads to Drp1 phosphorylation (Ser616) enhancing mitochondrial fission followed by a switch in cellular metabolism towards glycolysis. This cellular metabolism switch was in turn supported with a reduction in oxygen consumption rate upon BORIS expression. Interestingly methylome analysis revealed patterns of global histone methylation, a mechanism that regulate important signaling pathways in neuroblastoma. This study analyzes the consequence of BORIS expression in neuroblastoma cells and thereby elucidate its downstream targets, which could help in designing effective therapeutic for treating neuroblastoma. Similar results were obtained in both MYCN amplified and non-MYCN neuroblastoma cell lines, indicating a common mechanism of BORIS/CTCFL action in neuroblastoma.

Sevoflurane suppresses glioma tumorigenesis via regulating circ_0079593/miR-633/ROCK1 axis

BACKGROUND

Sevoflurane is a common inhalational anesthetic, which has been revealed to have anticancer effect in glioma. However, the mechanisms of sevoflurane in glioma progression remain largely unclear.

METHODS

Cell proliferation, cell cycle, apoptosis and metastasis were monitored by cell counting kit-8 (CCK-8), flow cytometry, Transwell and Western blot assays. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assays were used to examine the expression levels of circ_0079593, microRNA (miR)-633 and ROCK1 (Rho Associated Coiled-Coil Containing Protein Kinase 1). The dual-luciferase reporter assay was employed to confirm the targeting relationship between miR-633 and circ_0079593 or ROCK1. Animal experiment was conducted to explore the effect of sevoflurane in vivo.

RESULTS

Sevoflurane inhibited glioma cell proliferation, metastasis and induced apoptosis in vitro as well as impeded tumor growth in vivo. The expression of circ_0079593 was higher in glioma tissues and cells, and was decreased by sevoflurane treatment in glioma cells. Functional experiments showed that circ_0079593 overexpression in glioma cells reversed the inhibitory effects of sevoflurane on cell growth and metastasis. In a mechanism analysis, circ_0079593 acted as a sponge for miR-633 to elevate ROCK1 expression in glioma cells, and sevoflurane could regulate ROCK1 expression via circ_0079593/miR-633 axis. Besides that, circ_0079593/miR-633/ROCK1 axis mediated the protective effects of sevoflurane on glioma cell tumorigenesis.

CONCLUSION

Sevoflurane repressed glioma tumorigenesis via regulating circ_0079593/miR-633/ROCK1 axis, suggesting a new insight into the application of sevoflurane in glioma therapy.

Dichotomy in Growth and Invasion from Low- to High-Grade Glioma Cellular Variants

Glial dysfunction outraging CNS plasticity and integrity results in one of the most dangerous cancers, namely glioma, featuring little median survival period and high recurrence. The hallmark properties of proliferation, invasion and angiogenesis with the infiltrated macrophages in glioma are expected to be tightly coupled or cross-linked, but not properly related so far. The present study is aimed to find a relationship between this featured quadrangle from lower to higher grades (HG) of post-operative glioma tissues and their invading subsets. Elevated Ki67-associated proliferation in lower grades (LG) was supported with VEGF dependent angiogenic maintenance which found a decrease unlikely in HG. In contrast, MMP 2 and 9-associated invasions augmented high in HG with the dominant presence of CD204⁺ M2 polarized macrophages and a general increase in global DNMT1-associated methylation. Marked differences found in ECM invading cellular subsets of HG showing high proliferative capacity indicating rationally for recurrence, contrasting the nature of gross tumor tissue of the same grade. Thus in LG, the neoplastic lesion is more inclined to its growth while in higher grade more disposed towards tissue wreckage in support with cellular environmental milieu whereas the cellular variants and subsets of invaded cells showed different trends. Therefore, some operational dichotomy or coupling among cellular variants in glioma is active in determining its low- to high-grade transition and aggressive progression.

MicroRNA-663 Regulates Melanoma Progression by Inhibiting FHL3

microRNA-663a (miR-663a) was reported to be highly expressed in cancers. However, its roles in melanoma progression remain unclear. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was conducted to measure miR-663a expression level in melanoma cell lines and normal cells. Cell counting kit-8 assay, wound-healing assay, and transwell invasion assay were conducted to analyze biological roles of miR-663a in melanoma. Luciferase activity reporter assay was conducted to validate the connection of miR-663a and Four and a half LIM domain (FHL) protein 3 (FHL3) in melanoma. Our results showed miR-663a expression level was significantly increased in melanoma cells compared with normal cells. Silencing miR-663a expression suppresses melanoma cell proliferation, migration, and invasion in vitro. Moreover, FHL3 was validated as a functional target of miR-663a. Knockdown of FHL3 partially rescued the inhibitory effects of miR-663a inhibitor on melanoma cell behaviors. Together, our work provided evidence that miR-663a functions as an oncogenic miRNA in melanoma.

LncRNA PLAC2 upregulates miR-663 to downregulate TGF-β1 and suppress bladder cancer cell migration and invasion

BACKGROUND

The roles of lncRNA PLAC2 in bladder cancer (BC) were explored.

METHODS

The expression of PLAC2 in two types of tissue of BC patients was detected by RT-qPCR and the expression data were compared by paired t test. The 56 patients were staged according to the AJCC criteria, and 12, 15, 15 and 14 cases were classified into stage I-IV, respectively. The expression of TGF-β1 and miR-663 in BC tissues were also detected by RT-qPCR experiments.

RESULTS

Our data showed that the expression levels of PLAC2 were significantly lower in BC tissues than that in non-cancer tissues. The expression of PLAC2 was not affect by clinical stages and low expression levels of PLAC2 predicted lower survival rate. The expression of PLAC2 was positively correlated with miR-663 and inversely correlated with TGF-β1 in BC tissues. In BC cells, downregulated TGF-β1 and upregulated miR-663 were observed after the overexpression of PLAC2. Overexpression of PLAC2 also resulted in suppressed invasion and migration of BC cells. Overexpression of miR-663 resulted in downregulated TGF-β1 but did not affect the expression of PLAC2. Overexpression of TGF-β1 reduced the inhibitory effects of overexpression of PLAC2 and miR-663 on cell migration and invasion.

CONCLUSION

PLAC2 can upregulate miR-663 to downregulate TGF-β1 and suppress BC cell migration and invasion.

Glycyrrhetinic Acid-Induced MiR-663a Alleviates Hepatic Stellate Cell Activation by Attenuating the TGF-β/Smad Signaling Pathway

Glycyrrhetinic acid (GA), a hydrolysate of glycyrrhizic acid from licorice root extract, has been used to treat liver fibrotic diseases. However, the molecular mechanism involved in the antifibrotic effects of GA remains unclear. The involvement of miR-663a and its roles in TGF-β-1-induced hepatic stellate cell (HSC) activation remains unclear. In this study, we investigated the roles of miR-663a in the activation of HSCs and the antifibrosis mechanism of GA. MiR-663a expression was downregulated in TGF-β-treated HSCs. The overexpression of miR-663a inhibited HSC proliferation. TGF-β-1was confirmed as a direct target gene of miR-663a. MiR-663a alleviated HSC activation, concomitant with decreased expression of α-smooth muscle actin (α-SMA), human α2 (I) collagen (COL1A2), TGF-β1, TGF-βRI, Smad4, p-Smad2, and p-Smad3. GA upregulated miR-663a expression and inhibited the TGF-β/Smad pathway in HSCs. Further studies showed that miR-663a inhibitor treatment reversed GA-mediated downregulation of TGF-β1, TGF-βRI, Smad4, p-Smad2, p-Smad3, α-SMA, and CoL1A2 in TGF-β1-treated HSCs. These results show that miR-663a suppresses HSC proliferation and activation and the TGF-β/Smad signaling pathway, highlighting that miR-663a can be utilized as a therapeutic target for hepatic fibrosis. GA inhibits, at least in part, HSC proliferation and activation via targeting the miR-663a/TGF-β/Smad signaling pathway.

LncRNA RPSAP52 Upregulates TGF-β1 to Increase Cancer Cell Stemness and Predict Postoperative Survival in Glioblastoma

Introduction

Ribosomal protein SA pseudogene 52 (RPSAP52) has been characterized as an oncogenic lncRNA in pituitary tumors. Analysis of TCGA dataset revealed the upregulation of RPSAP52 in glioblastoma (GBM). We, therefore, investigated the roles of RPSAP52 in GBM.

Methods

A total of 50 GBM patients (33 males and 20 females; 54–75 years; mean age: 61.8±5.8 years) were selected from the 89 cases of GBM patients. Under the guidance of MRI, brain biopsy was performed to collect GBM tissues from each patient for the diagnosis of GBM. U-373 MG cells were employed and had transient transfections. qRNA, Western blot, and a series of experiments were performed to characterize their associations.

Results

The results showed that RPSAP52 was upregulated in GBM patients, and its high expression levels predicted poor survival. In GBM tissues, expression levels of RPSAP52 were significantly and positively correlated with that of TGF-β1. In GBM tissues, RPSAP52 positively regulated the expression of TGF-β1. Cell stemness assay showed that, compared to C and NC groups, overexpression of RPSAP52 and TGF-β1 led to increased, while silencing of RPSAP52 led to decreased CD133+ cells. Overexpression of TGF-β1 attenuated the effects of RPSAP52 siRNA silencing.

Conclusion

Therefore, RPSAP52 upregulates TGF-β1 to increase cancer cell stemness and predict postoperative survival in GBM.

Long Non-Coding RNA MACC1-AS1 Is Involved in Distant Recurrence of Hepatocellular Carcinoma After Surgical Resection

Background

We explored the role of MACC1-AS1 in hepatocellular carcinoma (HCC).

Material/Methods

Measurement of preoperative plasma levels of MACC1-AS1 was performed by qPCR, and the comparison between the HCC and Control group was performed by unpaired t test. The overexpression of TGF-β1 in SNU-182 and SNU-398 cells was confirmed by qPCR.

Results

MACC1-AS1 was overexpressed in HCC patients. In comparison to pretreatment level, distant recurrence (DR) was accompanied by increased levels of MACC1-AS1 in plasma, but this phenomenon was not observed in cases of local recurrence (LR) or non-recurrence (NR). In HCC cells, MACC1-AS1 positively regulated the expression of TGF-β1. MACC1-AS1 overexpression resulted in increased invasion and migration rates of HCC cells, while siRNA silencing resulted in reduced rates. Moreover, TGF-β1 overexpression reduced the effects of MACC1-AS1 siRNA silencing.

Conclusions

MACC1-AS1 is involved in the distant recurrence of HCC, and its actions are possibly mediated by TGF-β1.

The Roles of miRNA in Glioblastoma Tumor Cell Communication: Diplomatic and Aggressive Negotiations

Glioblastoma (GBM) consists of a heterogeneous collection of competing cellular clones which communicate with each other and with the tumor microenvironment (TME). MicroRNAs (miRNAs) present various exchange mechanisms: free miRNA, extracellular vesicles (EVs), or gap junctions (GJs). GBM cells transfer miR-4519 and miR-5096 to astrocytes through GJs. Oligodendrocytes located in the invasion front present high levels of miR-219-5p, miR-219-2-3p, and miR-338-3p, all related to their differentiation. There is a reciprocal exchange between GBM cells and endothelial cells (ECs) as miR-5096 promotes angiogenesis after being transferred into ECs, whereas miR-145-5p acts as a tumor suppressor. In glioma stem cells (GSCs), miR-1587 and miR-3620-5p increase the proliferation and miR-1587 inhibits the hormone receptor co-repressor-1 (NCOR1) after EVs transfers. GBM-derived EVs carry miR-21 and miR-451 that are up-taken by microglia and monocytes/macrophages, promoting their proliferation. Macrophages release EVs enriched in miR-21 that are transferred to glioma cells. This bidirectional miR-21 exchange increases STAT3 activity in GBM cells and macrophages, promoting invasion, proliferation, angiogenesis, and resistance to treatment. miR-1238 is upregulated in resistant GBM clones and their EVs, conferring resistance to adjacent cells via the CAV1/EGFR signaling pathway. Decrypting these mechanisms could lead to a better patient stratification and the development of novel target therapies.

PDIA4: The basic characteristics, functions and its potential connection with cancer

Disulfide bond formation is catalyzed by the protein disulfide Isomerases (PDI) family. This is a critical step in protein folding which occurs within the endoplasmic reticulum. PDIA4, as a member of the PDI family, can cause the adjustment of αIIβ 3 affinities which activate platelet and promote thrombosis formation. Endoplasmic reticulum response is triggered by accumulation of abnormal folding proteins concomitant with increasing PDIA4 expression. Besides, current researches indicate that activated platelets and ERS response affect tumor progression. And PDIA4, as previous reported, also participates in tumor progression by affecting cell apoptosis and DNA repair machinery without specific mechanisms revealed.Therefore, PDI inhibitor might possess great potential value in against tumor progression. In this review, we summarize information on PDIA4 including its the basic characteristics and its implication on tumor.

microRNAs: Potential glioblastoma radiosensitizer by targeting radiation-related molecular pathways

Glioblastoma (GBM) is the most lethal type of primary brain tumor. Currently, even with optimal and multimodal cancer therapies, the survival rate of GBM patients remains poor. One reason for inadequate response of GBM tumors to radiotherapy is radioresistance (RR). Thus, there is a critical need for new insights about GBM treatment to increase the chance of treatment. microRNAs (miRNAs) are important regulatory molecules that can effectively control GBM radiosensitivity (RS) by affecting radiation-related signal transduction pathways such as apoptosis, proliferation, DNA repair and cell cycle regulation. miRNAs provide new clinical perspectives for developing effective GBM treatments. A growing body of literature has demonstrated that GBM RS can be modified by modulating the expression of miRNAs such as miR-7, miR-10b, miR-124, miR-128, miR-320, miR-21, miR-203, and miR-153. This paper highlights the miRNAs and the underlying molecular mechanisms that are involved in the RS of GBM. Besides highlighting the role of miRNAs in different signaling pathways, we explain the mechanisms that affect RS of GBM for modulating radiation response at the clinical level.

MicroRNA-663 participates in myocardial fibrosis through interaction with TGF-β1

MicroRNA-663 (miRNA-663) regulates the expression of transforming growth factor β1 (TGF-β1), which participates in the pathogenesis of myocardial fibrosis. Therefore, microRNA-663 may also serve a role in myocardial fibrosis. The present study aimed to determine whether miRNA-663 participates in myocardial fibrosis via interaction with TGF-β1. In the present study, the expression of miRNA-663 was significantly downregulated, whereas that of TGF-β1 was significantly upregulated in the endomyocardial biopsies of patients with myocardial fibrosis compared with those in control necropsies. Pearson's correlation analysis revealed that the expression levels of miRNA-663 were negatively correlated with those of TGF-β1 in patients with myocardial fibrosis, but not in the controls. Receiver operating characteristic curve analysis demonstrated that the downregulation of miRNA-663 distinguished patients with myocardial fibrosis from controls. In the AC16 human cardiomyocyte cell line, miRNA-663 overexpression resulted in downregulated TGF-β1 expression, whereas exogenous TGF-β1 treatment exhibited no significant effects on miRNA-663 expression. These results indicate that miRNA-663 may participate in myocardial fibrosis, possibly through interaction with TGF-β1.

Glioblastoma Treatment Modalities besides Surgery

Glioblastoma multiforme (GBM) is commonly known as the most aggressive primary CNS tumor in adults. The mean survival of it is 14 to 15 months, following the standard therapy from surgery, chemotherapy, to radiotherapy. Efforts in recent decades have brought many novel therapies to light, however, with limitations. In this paper, authors reviewed current treatments for GBM besides surgery. In the past decades, only radiotherapy, temozolomide (TMZ), and tumor treating field (TTF) were approved by FDA. Though promising in preclinical experiments, therapeutic effects of other novel treatments including BNCT, anti-angiogenic therapy, immunotherapy, epigenetic therapy, oncolytic virus therapy, and gene therapy are still either uncertain or discouraging in clinical results. In this review, we went through current clinical trials, underlying causes, and future therapy designs to present neurosurgeons and researchers a sketch of this field.

Knockdown of SNHG8 repressed the growth, migration, and invasion of colorectal cancer cells by directly sponging with miR-663

Aberrant expression of SNHG8 has been observed in some types of cancers. However, whether SNHG8 was aberrantly expressed in colorectal cancer and whether it could exert any function on the development of colorectal cancer remains largely elusive. In this study, we first investigated the expression pattern and biological function of SNHG8 in colorectal cancer. The expression level of SNHG8 was investigated in colorectal cancer tissues as well as in colorectal cancer cell lines by real-time PCR. Next, CCK8 assays were performed to evaluate the effects of SNHG8 on the proliferation of colorectal cancer cells and transwell assays were employed to evaluate migration and invasion. Bioinformatics were used for predicting the sponging miRNAs that interact with SNHG8. A dual luciferase reporter assay was adopted for the verification of interaction between SNHG8 and miRNA. Our data showed that SNHG8 was significantly up-regulated in colorectal cancer tissues and cell lines. In addition, knockdown of SNHG8 significantly inhibited the growth, migration, and invasion of colorectal cancer cells. It was predicted that miR-663 might interact with SNHG8 and the direct sponging was verified by dual luciferase reporter assay. Moreover, rescue experiments revealed that SNHG8 played a tumor promoting role by regulating miR-663. In the present study, we revealed that SNHG8 was up-regulated in colorectal cancer and promoted the proliferation, migration, and invasion of colorectal cancer by sponging miR-663, which helps to further reveal the underlying developmental mechanism of action and provides a potential therapeutic molecule for colorectal cancer therapy in the future.

MicroRNA-663 induces immune dysregulation by inhibiting TGF-β1 production in bone marrow-derived mesenchymal stem cells in patients with systemic lupus erythematosus

Mesenchymal stem cells (MSCs) are critical for immune regulation. Although several microRNAs (miRNAs) have been shown to participate in autoimmune pathogenesis by affecting lymphocyte development and function, the roles of miRNAs in MSC dysfunction in autoimmune diseases remain unclear. Here, we show that patients with systemic lupus erythematosus (SLE) display a unique miRNA signature in bone marrow-derived MSCs (BMSCs) compared with normal controls, among which miR-663 is closely associated with SLE disease activity. MiR-663 inhibits the proliferation and migration of BMSCs and impairs BMSC-mediated downregulation of follicular T helper (Tfh) cells and upregulation of regulatory T (Treg) cells by targeting transforming growth factor β1 (TGF-β1). MiR-663 overexpression weakens the therapeutic effect of BMSCs, while miR-663 inhibition improves the remission of lupus disease in MRL/lpr mice. Thus, miR-663 is a key mediator of SLE BMSC regulation and may serve as a new therapeutic target for the treatment of lupus.

MicroRNA‑142‑3p inhibits trophoblast cell migration and invasion by disrupting the TGF‑β1/Smad3 signaling pathway

Insufficient invasion of trophoblasts is known to be associated with preeclampsia (PE) development. Recently, microRNAs (miRNAs) have been reported to serve important roles in the pathogenesis of PE. However, little is known regarding the regulation of trophoblastic invasion by miRNAs. The aim of the present study was to explore the role of miRNAs in trophoblastic invasion and the underlying molecular mechanism. Using a miRNA microarray, miRNAs putatively involved in the pathophysiology of PE were examined between normal and preeclamptic placentas. Validation analysis of miR‑142‑3p level in placenta specimens was performed using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Then, the regulation of miR‑142‑3p on trophoblast cells migration and invasion was evaluated using wound healing and transwell migration assays. Furthermore, the target gene of miR‑142‑3p and the downstream signaling pathway were also investigated. Microarray analysis and RT‑qPCR revealed that miR‑142‑3p was significantly upregulated in placenta specimens from patients with PE. Its overexpression inhibited trophoblast cell invasion and migration, whereas its knockdown enhanced trophoblast cell invasion and migration. In addition, overexpression of miR‑142‑3p inhibited the mRNA expression and the activities of matrix metalloproteinase‑2 (MMP2) and MMP9, which are closely associated with cell invasion and migration, while inhibition of miR‑142‑3p had the opposite result. Subsequent analyses demonstrated that transforming growth factor‑β1 (TGF‑β1) was a direct and functional target of miR‑142‑3p. Notably, the knockdown of TGF‑β1 effectively reversed the enhancement of miR‑142‑3p inhibitor on trophoblast cell invasion and migration. Finally, the present study confirmed that miR‑142‑3p inhibitor enhanced cell invasion and migration by reactivating the TGF‑β1/Smad3 signaling pathway. Taken together, the results of the present study suggest that miR‑142‑3p may serve an important role in human placental development by suppressing trophoblast cell invasion and migration through disruption of the TGF‑β1/smad3 signaling pathway, suggesting that knockdown of miR‑142‑3p may provide a novel therapy for PE.

miR663a‑TTC22V1 axis inhibits colon cancer metastasis

An increasing number of studies have demonstrated that microRNAs (miRs) may act as oncogenes or anti‑oncogenes in various types of cancer, including colon cancer (CC). However, the clinical and biological significance of miR663a in the prognosis of CC and its underlying molecular mechanisms remain unknown. Using the reverse transcription‑quantitative polymerase chain reaction on CC and surgical margin tissue samples from 172 patients with CC, it was identified that miR663a was significantly downregulated in CC (P<0.001), particularly in metastatic CC (P=0.044). miR663a overexpression inhibited the proliferation and migration/invasion of CC cells in vitro, and also tumor growth and metastasis of CC cells in vivo. Additionally, miR663a target genes were analyzed. Inverse changes in tetratricopeptide repeat domain 22 variant 1 (TTC22V1) in response to alterations in miR663a expression were observed. miR663a decreased the reporter activity of the wild‑type TTC22V1‑3' untranslated region (UTR), but did not decrease that of a 3'UTR mutant. miR663a completely abolished cell migration/invasion induced by TTC22V1 containing the wild‑type 3'UTR sequence, but not that induced by TTC22V1 containing the 3'UTR mutant. An inverse correlation between miR663a and TTC22 mRNA levels was observed in CC tissues. These results suggest that TTC22V1 mRNA is a crucial miR663a target that directly promotes cell migration/invasion. TTC22, which, to the best of our knowledge, has rarely been investigated, is located in the nuclei of epithelial cells in colon stem cell niches at crypt bases, and is significantly downregulated in CC, particularly in non‑metastatic CC. High TTC22V1 expression is a significant poor survival factor for patients with CC. Collectively, the results of the present study suggested that TTC22V1 may be a metastasis‑associated gene and that the miR663a‑TTC22V1 axis inhibited CC metastasis.

MiR-101-3p inhibits EMT to attenuate proliferation and metastasis in glioblastoma by targeting TRIM44

BACKGROUND

Glioblastoma (GBM) is the most common malignant tumor originating in the brain parenchyma. The invasive and infiltrative properties of glioblastoma result in poor clinical prognosis to conventional therapies. Emerging reports on microRNAs as important regulators during the process of EMT provide new insights into treating glioblastoma through new targets. However, underlying molecular mechanism of the regulation of miR-101-3p in glioblastoma remains unclear.

METHODS

Level of miR-101-3p was determined in GBM cell lines by qRT-PCR. MTT, colony formation and transwell assays were utilized to evaluate functions of overexpression of miR-101-3p/knock down of TRIM44 on proliferation, migration and invasion in GBM cells. Direct interaction between miR-101-3p and TRIM44 was validated using dual luciferase reporter system and impacts of overexpression of miR-101-3p/knock down of TRIM44 on regulation of EMT markers were assessed by Western blotting.

RESULTS

MiR-101-3p was validated to be repressed expressed in glioblastoma cancer cell lines. Both overexpression of miR-101-3p and knock down of TRIM44 attenuated proliferation, migration and invasion of glioblastoma cell lines in vitro. TRIM44 was shown to promote EMT in GBM progress and reverse inhibitory function of miR-101-3p. MiR-101-3p was found to suppress the expression of TRIM44 via directly targeting its 3'UTR.

CONCLUSIONS

Our findings suggested miR-101-3p regulated proliferation and migration of glioblastoma cells through attenuating TRIM44 induced EMT via direct targeting 3'UTR of TRIM44, which provided preliminary study of potential therapeutic target in future GBM treatment.

miR-663a inhibits tumor growth and invasion by regulating TGF-β1 in hepatocellular carcinoma

Background

The dysregulation of miR-663a is frequently observed in many human cancers. However, the functional role and precise mechanism of miR-663a have been controversial in hepatocellular carcinoma (HCC) and need to be studied in depth.

Methods

The expression of miR-663a was detected in human cell lines and HCC tissues by quantitative RT-PCR (qRT-PCR), and data from the Cancer Genome Atlas (TCGA). Cell proliferation was investigated using MTS, EdU, colony formation assays, and xenograft animal experiments, and the cell invasion capacity was evaluated using the transwell assay. The target gene of miR-663a was identified by qRT-PCR, Western blot, and dual-luciferase reporter assays. The clinicopathological features of miR-663a and the correlation between miR-663a and TGF-β1 expression were also investigated in the clinical samples of HCC.

Results

miR-663a was significantly downregulated in HCC cells relative to immortal normal liver cells, as indicated using qRT-PCR, and the lower expression of miR-663a was also confirmed in HCC tissue samples and the data from TCGA. The expression of miR-663a in HCC tissue samples was statistically significantly associated with size and the number of tumors. In addition, the upregulation of miR-663a inhibited the proliferation and invasion of HCC cells in vitro. Further study showed that miR-663a directly targeted transforming growth factor beta 1 (TGF-β1) to suppress HCC invasion, and that the inhibitory effect of miR-663a on cell invasion could be regulated by TGF-β1. In vivo studies showed that miR-663a significantly inhibited tumor growth. A negative correlation between miR-663a and TGF-β1 expression was also confirmed from the clinical samples of HCC.

Conclusions

miR-663a acts as a tumor suppressor and exerts a substantial role in inhibiting the proliferation, invasion, and tumorigenesis of HCC by regulating TGF-β1 in vitro and in vivo. These observations indicate that miR-663a may be a suitable diagnostic, therapeutic, and prognostic target for the treatment of HCC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5016-z) contains supplementary material, which is available to authorized users.

Aberrant miRNAs Regulate the Biological Hallmarks of Glioblastoma

GBM is the highest incidence in primary intracranial malignancy, and it remains poor prognosis even though the patient is gave standard treatment. Despite decades of intense research, the complex biology of GBM remains elusive. In view of eight hallmarks of cancer which were proposed in 2011, studies related to the eight biological capabilities in GBM have made great progress. From these studies, it can be inferred that miRs, as a mode of post-transcriptional regulation, are involved in regulating these malignant biological hallmarks of GBM. Herein, we discuss state-of-the-art research on how aberrant miRs modulate the eight hallmarks of GBM. The upregulation of 'oncomiRs' or the genetic loss of tumor suppressor miRs is associated with these eight biological capabilities acquired during GBM formation. Furthermore, we also discuss the applicable clinical potential of these research results. MiRs may aid in the diagnosis and prognosis of GBM. Moreover, miRs are also therapeutic targets of GBM. These studies will develop and improve precision medicine for GBM in the future.

MiR-663, a MicroRNA Linked with Inflammation and Cancer That Is under the Influence of Resveratrol

Resveratrol (trans-3,5,4′-trihydroxystilbene, RSV) is a non-flavonoid dietary polyphenol with antioxidant, anti-inflammatory and anti-cancer properties that is primarily found in red berries. While RSV displays many beneficial effects in vitro, its actual effects in vivo or in animal models remain passionately debated. Recent publications suggest that RSV pleiotropic effects could arise from its capability to regulate the expression and activity of microRNAs, short regulators themselves capable of regulating up to several hundreds of target genes. In particular, RSV increases microRNA miR-663 expression in different human cell lines, suggesting that at least some of its multiple beneficial properties are through the modulation of expression of this microRNA. Indeed, the expression of microRNA miR-663 is reduced in certain cancers where miR-663 is considered to act as a tumor suppressor gene, as well as in other pathologies such as cardiovascular disorders. Target of miR-663 include genes involved in tumor initiation and/or progression as well as genes involved in pathologies associated with chronic inflammation. Here, we review the direct and indirect effects of RSV on the expression of miR-663 and its target transcripts, with emphasise on TGFβ1, and their expected health benefits, and argue that elucidating the molecular effects of different classes of natural compounds on the expression of microRNAs should help to identify new therapeutic targets and design new treatments.

MicroRNA-663 regulates the proliferation of fibroblasts in hypertrophic scars via transforming growth factor-β1

The present study determined the expression of microRNA (miR)-663 in hypertrophic scar (HS) tissues and investigate the regulatory mechanisms of miR-663 in HS. A total of 51 patients diagnosed with HS between December 2013 and February 2016 were included in the present study. HS tissues (experimental group) and HS-adjacent tissues (control group) were collected. Primary fibroblasts were obtained from HS tissue and transfected with small-interfering RNA against transforming growth factor (TGF)-β1 or miR-663 mimics. Reverse-transcription quantitative PCR was used to determine the levels of TGF-β1 mRNA and miR-663. Western blot analysis was performed to determine TGF-β1 protein expression. An MTT assay was employed to detect the proliferation of fibroblasts, and a dual luciferase reporter assay was performed to identify the binding of miR-663 with TGF-β1 mRNA. TGF-β1 was found to have a regulatory role in HS at the transcriptional level. The expression of TGF-β1 was upregulated in HS tissues, and knockdown of TGF-β1 in cultured fibroblasts led to inhibition of proliferation. The expression of miR-663 was downregulated in HS. miR-663 was revealed to regulate the expression of TGF-β1 by binding with the 3′-untranslated region of TGF-β1 mRNA. Elevated expression of miR-663 inhibited the proliferation of fibroblasts by regulating TGF-β1 expression. The present study demonstrated that upregulation of TGF-β1 in HS tissues is associated with the downregulation of miR-663 expression. miR-663 may regulate the proliferation of fibroblasts in HS and the expression of associated proteins.

Migration/Invasion of Malignant Gliomas and Implications for Therapeutic Treatment

Malignant tumors of the central nervous system (CNS) are among cancers with the poorest prognosis, indicated by their association with tumors of high-level morbidity and mortality. Gliomas, the most common primary CNS tumors that arise from neuroglial stem or progenitor cells, have estimated annual incidence of 6.6 per 100,000 individuals in the USA, and 3.5 per 100,000 individuals in Taiwan. Tumor invasion and metastasis are the major contributors to the deaths in cancer patients. Therapeutic goals including cancer stem cells (CSC), phenotypic shifts, EZH2/AXL/TGF-β axis activation, miRNAs and exosomes are relevant to GBM metastasis to develop novel targeted therapeutics for GBM and other brain cancers. Herein, we highlight tumor metastasis in our understanding of gliomas, and illustrate novel exosome therapeutic approaches in glioma, thereby paving the way towards innovative therapies in neuro-oncology.

Characterization of brain tumor initiating cells isolated from an animal model of CNS primitive neuroectodermal tumors

CNS Primitive Neuroectodermal tumors (CNS-PNETs) are members of the embryonal family of malignant childhood brain tumors, which remain refractory to current therapeutic treatments. Current paradigm of brain tumorigenesis implicates brain tumor-initiating cells (BTIC) in the onset of tumorigenesis and tumor maintenance. However, despite their significance, there is currently no comprehensive characterization of CNS-PNETs BTICs. Recently, we described an animal model of CNS-PNET generated by orthotopic transplantation of human Radial Glial (RG) cells - the progenitor cells for adult neural stem cells (NSC) - into NOD-SCID mice brain and proposed that BTICs may play a role in the maintenance of these tumors. Here we report the characterization of BTIC lines derived from this CNS-PNET animal model. BTIC’s orthotopic transplantation generated highly aggressive tumors also characterized as CNS-PNETs. The BTICs have the hallmarks of NSCs as they demonstrate self-renewing capacity and have the ability to differentiate into astrocytes and early migrating neurons. Moreover, the cells demonstrate aberrant accumulation of wild type tumor-suppressor protein p53, indicating its functional inactivation, highly up-regulated levels of onco-protein cMYC and the BTIC marker OCT3/4, along with metabolic switch to glycolysis - suggesting that these changes occurred in the early stages of tumorigenesis. Furthermore, based on RNA- and DNA-seq data, the BTICs did not acquire any transcriptome-changing genomic alterations indicating that the onset of tumorigenesis may be epigenetically driven. The study of these BTIC self-renewing cells in our model may enable uncovering the molecular alterations that are responsible for the onset and maintenance of the malignant PNET phenotype.

Paeoniflorin Inhibits Migration and Invasion of Human Glioblastoma Cells via Suppression Transforming Growth Factor β-Induced Epithelial-Mesenchymal Transition

Paeoniflorin (PF) is a polyphenolic compound derived from Radix Paeoniae Alba thathas anti-cancer activities in a variety of human malignancies including glioblastoma. However, the underlying mechanisms have not been fully elucidated. Epithelial to mesenchymal transition (EMT), characterized as losing cell polarity, plays an essential role in tumor invasion and metastasis. TGFβ, a key member of transforming growth factors, has been demonstrated to contribute to glioblastoma aggressiveness through inducing EMT. Therefore, the present studies aim to investigate whether PF suppresses the expression of TGFβ and inhibits EMT that plays an important role in anti-glioblastoma. We found that PF dose-dependently downregulates the expression of TGFβ, enhances apoptosis, reduces cell proliferation, migration and invasion in three human glioblastoma cell lines (U87, U251, T98G). These effects are enhanced in TGFβ siRNA treated cells and abolished in cells transfected with TGFβ lentiviruses. In addition, other EMT markers such as snail, vimentin and N-cadherin were suppressed by PF in these cell lines and in BALB/c nude mice injected with U87 cells. The expression of MMP2/9, EMT markers, are also dose-dependently reduced in PF treated cells and in U87 xenograft mouse model. Moreover, the tumor sizes are reduced by PF treatment while there is no change in body weight. These results indicate that PF is a potential novel drug target for the treatment of glioblastoma by suppression of TGFβ signaling pathway and inhibition of EMT.

Underlying mechanism of the photodynamic activity of hematoporphyrin‑induced apoptosis in U87 glioma cells

Photodynamic therapy (PDT) is a relatively novel type of tumor therapy method with low toxicity and limited side‑effects. The aim of the present study was to investigate the underlying mechanism and potential microRNAs (miRNAs) involved in the treatment of glioma by PDT with hematoporphyrin, a clinical photosensitizer. The photodynamic activity of hematoporphyrin on the cell viability and apoptosis of gliomas was investigated by MTT, and flow cytometry and fluorescence microscopy, respectively. Alterations in singlet oxygen and mitochondrial membrane potential were detected. The differentially expressed miRNAs and proteins were evaluated by miRNA gene chip and apoptosis‑associated protein chip, respectively. The results demonstrated that cell viability significantly decreased with hematoporphyrin concentration. PDT with hematoporphyrin significantly increased cell apoptosis at a later stage, induced the content of reactive oxygen species (ROS) and decreased the mitochondrial membrane potential, indicating that PDT with hematoporphyrin inhibited cell growth via induction of radical oxygen, decreased the mitochondrial membrane potential and induced apoptosis. The upregulated miRNAs, including hsa‑miR‑7641, hsa‑miR‑9500, hsa‑miR‑4459, hsa‑miR‑21‑5p, hsa‑miR‑663a and hsa‑miR‑205‑5p may be important in PDT‑induced cell apoptosis in glioma. Transporter 1, ATP binding cassette subfamily B member‑ and nuclear factor‑κB‑mediated apoptosis signaling pathways were the most significant pathways. Thus, the current study presents PDT as a potential therapeutic approach for the treatment of malignant glioma, and identified miRNAs for the molecular design and development of a third‑generation photosensitizer (PS).

Elucidating mechanisms of sunitinib resistance in renal cancer: an integrated pathological-molecular analysis

Upon sunitinib treatment of metastatic renal cell carcinoma patients eventually acquire resistance. Our aim was to investigate microRNAs behind sunitinib resistance.

We developed an in vivo xenograft and an in vitro model and compared morphological, immunhistochemical, transcriptomical and miRNome data changes during sunitinib response and resistance by performing next-generation mRNA and miRNA sequencing. Complex bioinformatics (pathway, BioFunction and network) analysis were performed. Results were validated by in vitro functional assays.

Our morphological, immunhistochemical, transcriptomical and miRNome data all pointed out that during sunitinib resistance tumor cells changed to migratory phenotype. We identified the downregulated miR-1 and miR-663a targeting FRAS1 (Fraser Extracellular Matrix Complex Subunit 1) and MDGA1 (MAM Domain Containing Glycosylphosphatidylinositol Anchor 1) in resistant tumors. We proved firstly miR-1-FRAS1 and miR-663a-MDGA1 interactions. We found that MDGA1 knockdown decreased renal cancer cell migration and proliferation similarly to restoration of levels of miR-1 and miR-663.

Our results support the central role of cell migration as an adaptive mechanism to secure tumor survival behind sunitinib resistance. MDGA1, FRAS1 or the targeting miRNAs can be potential adjuvant therapeutic targets, through inhibition of cancer cell migration, thus eliminating the development of resistance and metastasis.

Epigenetic modification of miR-663 controls mitochondria-to-nucleus retrograde signaling and tumor progression

The normal cellular function requires communication between mitochondria and the nucleus, termed mitochondria-to-nucleus retrograde signaling. Disruption of this mechanism has been implicated in the development of cancers. Many proteins are known modulators of retrograde signaling, but whether microRNAs (miRNAs) are also involved is unknown. We conducted an miRNA microarray analysis using RNA from a parental cell line, a Rho⁰ line lacking mitochondrial DNA (mtDNA) and a Rho⁰ line with restored mtDNA. We found that miR-663 was down-regulated in the mtDNA-depleted Rho⁰ line. mtDNA restoration reversed this miRNA to parental level, suggesting that miR-663 may be epigenetically regulated by retrograde signaling. By using methylation-specific PCR and bisulfite sequencing we demonstrate that miR-663 promoter is epigenetically regulated not only by genetic but also by pharmacological disruption of oxidative phosphorylation (OXPHOS). Restoration of OXPHOS Complex I inhibitor-induced miR-663 expression by N-acetylcysteine suggested that reactive oxygen species (ROS) play a key role in epigenetic regulation of miR-663. We determined that miR-663 regulates the expression of nuclear-encoded respiratory chain subunits involved in Complexes I, II, III, and IV. miR-663 also controlled the expression of the Complexes I (NDUFAF1), II (SDHAF2), III (UQCC2), and IV (SCO1) assembly factors and was required for stability of respiratory supercomplexes. Furthermore, using luciferase assays, we found that miR-663 directly regulates UQCC2. The anti-miR-663 reduced OXPHOS complex activity and increased in vitro cellular proliferation and promoted tumor development in vivo in mice. We also found that increased miR-663 expression in breast tumors consistently correlates with increased patient survival. We provide the first evidence for miRNA controlling retrograde signaling, demonstrating its epigenetic regulation and its role in breast tumorigenesis.

MicroRNA‑663 suppresses the proliferation and invasion of colorectal cancer cells by directly targeting FSCN1

Colorectal cancer (CRC) is the most frequently diagnosed malignancy of the gastrointestinal tract. The dysregulation of microRNAs (miRNAs/miRs) has been reported in the majority of types of human cancer, and is correlated with tumorigenesis and tumor development. Abnormal expression of miR‑663 has been observed in various types of human cancer. However, little is known about its role in CRC. Therefore, the aim of the present study was to clarify the expression and potential role of miR‑663, and its underlying molecular mechanism in CRC. It was observed that miR‑663 was markedly downregulated in CRC tissues and cell lines. Decreased miR‑663 expression levels in CRC tissues were correlated with tumor, node, metastasis stage and lymph node metastasis. Functional assays revealed that upregulation of miR‑663 inhibited cell proliferation and invasion in CRC. Further molecular mechanism assays demonstrated the fascin (FSCN1) was a target gene of miR‑663. In addition, FSCN1 was increased and negatively correlated with miR‑663 expression in CRC tissues. FSCN1 underexpression mimicked the tumor suppressive functions induced by miR‑663 overexpression on CRC cell proliferation and invasion. Collectively, the present study presented evidence that miR‑663 may act as a tumor suppressor in CRC by directly targeting FSCN1, which may lead to a potential therapeutic strategy focusing on miR‑663 and FSCN1 for patients with this disease.

MicroRNA‑329 serves a tumor suppressive role in colorectal cancer by directly targeting transforming growth factor beta‑1

Colorectal cancer (CRC) is the third most common type of diagnosed cancer and the fourth leading cause of cancer‑associated mortalities worldwide. Increasing studies have demonstrated that the deregulation of microRNAs (miRNAs or miRs) is associated with the occurrence and development of multiple types of human cancer, including CRC. miR‑329 has been identified to be downregulated in various types of cancer; however, its expression pattern, functions and mechanisms in CRC remain unclear. The present study demonstrated that miR‑329 was lowly expressed in CRC tissue samples and cell lines. Low expression of miR‑329 was correlated with tumor‑node‑metastasis stage and lymph node metastasis in patients with CRC. In vitro experiments revealed that resumption expression of miR‑329 suppressed cell proliferation and invasion in CRC. Furthermore, the results of the present study indicated that miR‑329 targets transforming growth factor‑β1 (TGF‑β1) directly in vitro. TGF‑β1 was demonstrated to be upregulated in CRC tissue samples and inversely correlated with miR‑329 expression. Upregulation of TGF‑β1 was able to partially counteract the antitumor roles of miR‑329 on CRC cell proliferation and invasion. The results of the current study revealed that miR‑329 suppresses CRC cell proliferation and invasion through targeting TGF‑β1, thus suggesting that targeting miR‑329/TGF‑β1 may provide a novel effective therapeutic approach for the treatment of patients with CRC.

miR-663b promotes tumor cell proliferation, migration and invasion in nasopharyngeal carcinoma through targeting TUSC2

The authors' previous study revealed that the serum levels of microRNA (miR)-663b are significantly increased in patients with nasopharyngeal carcinoma (NPC), and are associated with NPC progression and poor prognosis. However, the molecular mechanism of underlying NPC growth and metastasis remains unclear. In the present study, quantitative polymerase chain reaction and western blot analyses were performed to examine changes to mRNA and protein expression, respectively. MTT, wound healing and Transwell assays were used to examine cell proliferation, migration and invasion, respectively. Luciferase reporter gene assays were performed to identify target genes of miR-663b. It was demonstrated that miR-663b was significantly upregulated in NPC tissue compared with non-tumor nasopharyngeal epithelial tissue samples. Furthermore, miR-663b expression gradually increased with advancing stages of NPC, with the highest expression being observed in the latest stage IV. The increased expression of miR-663b was associated with advanced clinical stage and lymph node metastasis. In addition, miR-663b expression was increased in NPC cell lines compared with normal nasopharyngeal epithelial NP69 cells. Knockdown of miR-663b resulted in a significant reduction in the proliferation, migration and invasion of NPC CNE1 cells. Tumor suppressor candidate 2 (TUSC2) was identified as a novel target gene of miR-663b. It was further demonstrated that TUSC2 was significantly downregulated in NPC tissue samples and cell lines. miR-663b negatively regulated the expression of TUSC2 at the post-transcriptional level in CNE1 cells. Additionally, inhibition of TUSC2 expression attenuated the suppressive effects of miR-663b downregulation on the proliferation, migration and invasion of CNE1 cells. To the best of our knowledge, this is the first study to demonstrate that miR-663b, which is upregulated in NPC, promotes the proliferation, migration and invasion of NPC cells, partially through the inhibition of TUSC2 expression. Therefore, it is suggested that miR-663b is a promising therapeutic target for the treatment of patients with NPC.

Genome-wide DNA methylation sequencing reveals miR-663a is a novel epimutation candidate in CIMP-high endometrial cancer

Aberrant DNA methylation is widely observed in many cancers. Concurrent DNA methylation of multiple genes occurs in endometrial cancer and is referred to as the CpG island methylator phenotype (CIMP). However, the features and causes of CIMP-positive endometrial cancer are not well understood. To investigate DNA methylation features characteristic to CIMP-positive endometrial cancer, we first classified samples from 25 patients with endometrial cancer based on the methylation status of three genes, i.e. MLH1, CDH1 (E-cadherin) and APC: CIMP-high (CIMP-H, 2/25, 8.0%), CIMP-low (CIMP-L, 7/25, 28.0%) and CIMP-negative (CIMP(-), 16/25, 64.0%). We then selected two samples each from CIMP-H and CIMP(-) classes, and analyzed DNA methylation status of both normal (peripheral blood cells: PBCs) and cancer tissues by genome-wide, targeted bisulfite sequencing. Genomes of the CIMP-H cancer tissues were significantly hypermethylated compared to those of the CIMP(-). Surprisingly, in normal tissues of the CIMP-H patients, promoter region of the miR-663a locus is hypermethylated relative to CIMP(-) samples. Consistent with this finding, miR-663a expression was lower in the CIMP-H PBCs than in the CIMP(-) PBCs. The same region of the miR663a locus is found to be highly methylated in cancer tissues of both CIMP-H and CIMP(-) cases. This is the first report showing that aberrant DNA methylation of the miR-663a promoter can occur in normal tissue of the cancer patients, suggesting a possible link between this epigenetic abnormality and endometrial cancer. This raises the possibility that the hypermethylation of the miR-663a promoter represents an epimutation associated with the CIMP-H endometrial cancers. Based on these findings, relationship of the aberrant DNA methylation and CIMP-H phenotype is discussed.

Blocking epithelial-to-mesenchymal transition in glioblastoma with a sextet of repurposed drugs: the EIS regimen

This paper outlines a treatment protocol to run alongside of standard current treatment of glioblastoma- resection, temozolomide and radiation. The epithelial to mesenchymal transition (EMT) inhibiting sextet, EIS Regimen, uses the ancillary attributes of six older medicines to impede EMT during glioblastoma. EMT is an actively motile, therapy-resisting, low proliferation, transient state that is an integral feature of cancers’ lethality generally and of glioblastoma specifically. It is believed to be during the EMT state that glioblastoma’s centrifugal migration occurs. EMT is also a feature of untreated glioblastoma but is enhanced by chemotherapy, by radiation and by surgical trauma. EIS Regimen uses the antifungal drug itraconazole to block Hedgehog signaling, the antidiabetes drug metformin to block AMP kinase (AMPK), the analgesic drug naproxen to block Rac1, the anti-fibrosis drug pirfenidone to block transforming growth factor-beta (TGF-beta), the psychiatric drug quetiapine to block receptor activator NFkB ligand (RANKL) and the antibiotic rifampin to block Wnt- all by their previously established ancillary attributes. All these systems have been identified as triggers of EMT and worthy targets to inhibit. The EIS Regimen drugs have a good safety profile when used individually. They are not expected to have any new side effects when combined. Further studies of the EIS Regimen are needed.

Upfront boost Gamma Knife “leading-edge” radiosurgery to FLAIR MRI–defined tumor migration pathways in 174 patients with glioblastoma multiforme: a 15-year assessment of a novel therapy

OBJECTIVE

Glioblastoma multiforme (GBM) is composed of cells that migrate through the brain along predictable white matter pathways. Targeting white matter pathways adjacent to, and leading away from, the original contrast-enhancing tumor site (termed leading-edge radiosurgery [LERS]) with single-fraction stereotactic radiosurgery as a boost to standard therapy could limit the spread of glioma cells and improve clinical outcomes.

METHODS

Between December 2000 and May 2016, after an initial diagnosis of GBM and prior to or during standard radiation therapy and carmustine or temozolomide chemotherapy, 174 patients treated with radiosurgery to the leading edge (LE) of tumor cell migration were reviewed. The LE was defined as a region outside the contrast-enhancing tumor nidus, defined by FLAIR MRI. The median age of patients was 59 years (range 22–87 years). Patients underwent LERS a median of 18 days from original diagnosis. The median target volume of 48.5 cm3 (range 2.5–220.0 cm3) of LE tissue was targeted using a median dose of 8 Gy (range 6–14 Gy) at the 50% isodose line.

RESULTS

The median overall survival was 23 months (mean 43 months) from diagnosis. The 2-, 3-, 5-, 7-, and 10-year actual overall survival rates after LERS were 39%, 26%, 16%, 10%, and 4%, respectively. Nine percent of patients developed treatment-related imaging-documented changes due to LERS. Nineteen percent of patients were hospitalized for management of edema, 22% for resection of a tumor cyst or new tumor bulk, and 2% for shunting to treat hydrocephalus throughout the course of their disease. Of the patients still alive, Karnofsky Performance Scale scores remained stable in 90% of patients and decreased by 1–3 grades in 10% due to symptomatic treatment-related imaging changes.

CONCLUSIONS

LERS is a safe and effective upfront adjunctive therapy for patients with newly diagnosed GBM. Limitations of this study include a single-center experience and single-institution determination of the LE tumor target. Use of a leading-edge calculation algorithm will be described to achieve a consistent approach to defining the LE target for general use. A multicenter trial will further elucidate its value in the treatment of GBM.

Inhibition of S-Adenosylmethionine-Dependent Methyltransferase Attenuates TGFβ1-Induced EMT and Metastasis in Pancreatic Cancer: Putative Roles of miR-663a and miR-4787-5p

The identification of epigenetic reversal agents for use in combination chemotherapies to treat human pancreatic ductal adenocarcinomas (PDAC) remains an unmet clinical need. Pharmacologic inhibitors of Enhancer of Zeste Homolog 2 (EZH2) are emerging as potential histone methylation reversal agents for the treatment of various solid tumors and leukemia; however, the surprisingly small set of mRNA targets identified with EZH2 knockdown suggests novel mechanisms contribute to their antitumorigenic effects. Here, 3-deazaneplanocin-A (DZNep), an inhibitor of S-adenosyl-L-homocysteine hydrolase and EZH2 histone lysine-N-methyltransferase, significantly reprograms noncoding microRNA (miRNA) expression and dampens TGFβ1-induced epithelial-to-mesenchymal (EMT) signals in pancreatic cancer. In particular, miR-663a and miR-4787-5p were identified as PDAC-downregulated miRNAs that were reactivated by DZNep to directly target TGFβ1 for RNA interference. Lentiviral overexpression of miR-663a and miR-4787-5p reduced TGFβ1 synthesis and secretion in PDAC cells and partially phenocopied DZNep's EMT-resisting effects, whereas locked nucleic acid (LNA) antagomiRNAs counteracted them. DZNep, miR-663a, and miR-4787-5p reduced tumor burden in vivo and metastases in an orthotopic mouse pancreatic tumor model. Taken together, these findings suggest the epigenetic reprogramming of miRNAs by synthetic histone methylation reversal agents as a viable approach to attenuate TGFβ1-induced EMT features in human PDAC and uncover putative miRNA targets involved in the process.

IMPLICATIONS

The findings support the potential for synthetic histone methylation reversal agents to be included in future epigenetic-chemotherapeutic combination therapies for pancreatic cancer. Mol Cancer Res; 14(11); 1124-35. ©2016 AACR.

Increased Serum Level of MicroRNA-663 Is Correlated with Poor Prognosis of Patients with Nasopharyngeal Carcinoma

MicroRNAs (miRs) play crucial roles in the carcinogenesis and malignant progression of human cancers including nasopharyngeal carcinoma (NPC). In this study, we aimed to investigate the association of serum miR-663 levels with the clinical factors and prognosis of NPC patients. Real-time PCR was performed to examine the amount of miR-663 in serum in NPC patients and healthy controls. Our data showed that the amount of miR-663 in serum was significantly higher in NPC patients than in healthy controls. Moreover, the serum levels of miR-663 were significantly correlated with the grade, lymph node metastasis, and clinical stage of NPC. Furthermore, higher serum miR-663 levels were closely associated with worse 5-year overall survival (OS) and relapse-free survival (RFS) of patients with NPC, and the serum level of miR-663 was found to be an independent predicator for the prognosis of NPC. In addition, after receiving chemoradiotherapy, the serum levels of miR-663 were significantly reduced in NPC patients. In summary, miR-663 was upregulated in the serum of NPC patients, which was downregulated after chemoradiotherapy, and its increased levels were closely associated with malignant progression and poor prognosis in NPC patients. Therefore, the amount of miR-663 in serum may become a potential predicator for the clinical outcome of NPC patients.

MiR-595 targeting regulation of SOX7 expression promoted cell proliferation of human glioblastoma

Increasing evidence indicated that dysregulation of microRNAs (miRNAs) were involved with human disease including cancer. Recently, miR-595 was reported as a tumor promoter in malignant mesothelioma. However, the underlying mechanism of miR-595 in human glioblastoma (GBM) cells have not been well elucidated. Therefore, in this study, we investigated the biological functions and molecular mechanisms of miR-595 in human GBM. MiR-595 expression was significantly upregulated in GBM tissues and cells. We modified miR-595 levels in GBM cells and investigated their effects on the cell proliferation by MTT, colony formation and anchorage-independent growth assays. We found that miR-595 significantly increased GBM cell proliferation. Bioinformatic analysis predicted that miR-595 may target the 3'-UTR of SOX7and suppressed its translation, and further confirmed by luciferase assay. In sum, these observations together indicated that miR-595 played a critical role in carcinogenesis by suppression of SOX7, and may serve as a therapeutic target for the treatment of GBM.