miR-145 suppresses colorectal cancer cell migration and invasion by targeting an ETS-related gene

Exosomal delivery of miR-200b-3p suppresses the growth of hepatocellular carcinoma cells by targeting ERG- and VEGF-mediated angiogenesis

Hepatocellular carcinoma (HCC) remains a lethal malignancy with limited treatment options. Recent discoveries have highlighted the pivotal role of miRNAs in HCC progression. We previously reported that the expression of miR-200b-3p was decreased in HCC cells and exosomal miR-200b-3p from hepatocytes inhibited angiogenesis by suppressing the expression of the endothelial transcription factor ERG (erythroblast transformation-specific (ETS)-related gene), leading to the hypothesis that the delivery of this miRNA may inhibit angiogenesis and suppress HCC growth in vivo. Here, we tested this hypothesis by using human HCC inoculation models. First, we transfected the human HepG2 HCC cells and established a stable cell line that overexpressed a high level of miR-200b-3p. When miR-200b-3p-overexpressing cells were injected into severe combined immunedeficiency (SCID)-beige mice, tumor growth was significantly reduced compared to tumors of control cells, with a reduction in the expression of ERG and vascular endothelial growth factor (VEGF) and subsequent angiogenesis. Intra-tumoral injection of exosomes containing high levels of miR-200b-3p also reduced the growth of parental HepG2 tumors with reduced ERG and VEGF expression and angiogenesis. These results validate the inhibitory role of miR-200b-3p in tumor angiogenesis, thereby suppressing HCC tumor growth, and provide a novel insight into its potential therapeutic application.

Resident vascular Sca1+ progenitors differentiate into endothelial cells in vascular remodeling via miR-145-5p/ERG signaling pathway

Endothelial cell (EC) damage or dysfunction serves as the initial event in the pathogenesis of various cardiovascular diseases. Progenitor cells have been postulated to be able to differentiate into ECs, facilitate endothelial regeneration, and alleviate vascular pathological remodeling. However, the precise cellular origins and underlying mechanisms remain elusive. Through single-cell RNA sequencing (scRNA-seq), we identified an increasing population of progenitors expressing stem cell antigen 1 (Sca1) during vascular remodeling in mice. Using both mouse femoral artery injury and vein graft models, we determined that Sca1+ cells differentiate into ECs, restored endothelium in arterial and venous remodeling processes. Notably, we have observed that the differentiation of Sca1+ cells into ECs is negatively regulated by the microRNA-145-5p (miR-145-5p)-Erythroblast transformation-specific-related gene (ERG) pathway. Inhibiting miR-145-5p promoted Sca1+ cell differentiation and reduced neointimal formation after vascular injury. Finally, a similar downregulation of miR-145-5p in human arteriovenous fistula was observed comparing to healthy veins.

Targeted exosome-based nanoplatform for new-generation therapeutic strategies

Exosomes, typically 30-150 nm in size, are lipid-bilayered small-membrane vesicles originating in endosomes. Exosome biogenesis is regulated by the coordination of various mechanisms whereby different cargoes (e.g. proteins, nucleic acids, and lipids) are sorted into exosomes. These components endow exosomes with bioregulatory functions related to signal transmission and intercellular communication. Exosomes exhibit substantial potential as drug-delivery nanoplatforms owing to their excellent biocompatibility and low immunogenicity. Proteins, miRNA, siRNA, mRNA, and drugs have been successfully loaded into exosomes, and these exosome-based delivery systems show satisfactory therapeutic effects in different disease models. To enable targeted drug delivery, genetic engineering and chemical modification of the lipid bilayer of exosomes are performed. Stimuli-responsive delivery nanoplatforms designed with appropriate modifications based on various stimuli allow precise control of on-demand drug delivery and can be utilized in clinical treatment. In this review, we summarize the general properties, isolation methods, characterization, biological functions, and the potential role of exosomes in therapeutic delivery systems. Moreover, the effective combination of the intrinsic advantages of exosomes and advanced bioengineering, materials science, and clinical translational technologies are required to accelerate the development of exosome-based delivery nanoplatforms.

The Simultaneous Effects of miR-145-5p and hsa-let-7a-3p on Colorectal Tumorigenesis: In Vitro Evidence

Purpose

MicroRNAs (miRNAs) are a group of small regulatory non-coding RNAs, which are dysregulated through tumor progression. let-7 and MIR-145 are both tumor suppressor microRNAs that are downregulated in a wide array of cancers including colorectal cancer (CRC).

Methods

This study was aimed to investigate the effect of simultaneous replacement of these two tumor suppressor miRNAs on proliferation, apoptosis, and migration of CRC cells. HCT-116 with lower expression levels of hsa-let-7a-3p and MIR-145-5p was selected for functional investigations. The cells were cultured and transfected with hsa-let-7a and MIR-145, separately and in combination. Cell viability and apoptosis rates were assessed by MTT assay and flow cytometry, respectively. Cell cycle status was further evaluated using flow cytometry and qRT-PCR was employed to evaluate gene expression.

Results

The obtained results showed that exogenous overexpression of MIR-145 and hsa-let-7a in HCT-116 cells could cooperatively decrease CRC cell proliferation and induce sub-G1 cell cycle arrest. Moreover, hsa-let-7a and MIR-145 co-transfection significantly increased apoptosis induction compared to separate transfected cells and control through modulating the expression levels of apoptosis-related genes including Bax, Bcl-2, P53, Caspase-3, Caspase-8, and Caspase-9. Furthermore, qRT-PCR results illustrated that hsa-let-7a and MIR-145 combination more effectively downregulated MMP-9 and MMP-2 expression, as the important modulators of metastasis, compared to the controls.

Conclusion

Taken together, considering that exogenous overexpression of MIR-145 and hsa-let-7a showed cooperative anti-cancer effects on CRC cells, their combination may be considered as a novel therapeutic strategy for the treatment of CRC.

ETV7 promotes colorectal cancer progression through upregulation of IFIT3

Members of the E26 transformation-specific (ETS) variant transcription factor family act as either tumor suppressors or oncogenic factors in numerous types of cancer. ETS variant transcription factor 7 (ETV7) participates in the development of malignant tumors, whereas its involvement in colorectal cancer (CRC) is less clear. In this study, The Cancer Genome Atlas (TCGA) and immunochemistry staining were applied to check the clinical relevance of ETV7 and interferon-induced protein with tetratricopeptide repeats 3 (IFIT3) in CRC patients. Overexpression and knockdown of ETV7 and IFIT3 were conducted by transfecting the cells with pCDNA3.1 plasmids and siRNAs, respectively. Western blotting was used to detect the protein expression of ETV7 in CRC cells. Cell Counting Kit-8, cell colony formation, and Transwell assays, as well as flow cytometry, were used to evaluate the proliferation, migration, cell cycle, and apoptosis of CRC cells. Furthermore, western blotting, RT-qPCR, and luciferase assay were used to explore the regulation of ETV7 on IFIT3. Rescue assay was used to investigate the significance of ETV7/IFIT3 axis on CRC progression. We found that ETV7 was upregulated in CRC tissues and cells. Overexpression of ETV7 stimulated the proliferation, migration, and cell cycle amplification, and reduced the apoptosis of CRC cells. Downregulation of ETV7 exerted the opposite effect on CRC cell progression. Moreover, we demonstrated that ETV7 stimulated the transcription activity, the mRNA and protein expression of IFIT3 in CRC cells. There was a positive correlation between ETV7 and IFIT3 in CRC patients. IFIT3 knockdown reversed the promotive effect exerted by overexpression of ETV7 on the amplification and migration of CRC cells. By contrast, overexpression of IFIT3 blocked the inhibitory effect of ETV7-targeting siRNA. In summary, ETV7 induces progression of CRC by activating the transcriptional expression of IFIT3. The EVT7/IFIT3 axis may be a novel target for CRC therapy.

Detecting colorectal cancer using genetic and epigenetic biomarkers: screening and diagnosis

Colorectal cancer (CRC) is one of the most frequent types of cancer, with high incidence rates and mortality globally. The extended timeframe for developing CRC allows for the potential screening and early identification of the disease. Furthermore, studies have shown that survival rates for patients with cancer are increased when diagnoses are made at earlier stages. Recent research suggests that the development of CRC, including its precancerous lesion, is influenced not only by genetic factors but also by epigenetic variables. Studies suggest epigenetics plays a significant role in cancer development, particularly CRC. While this approach is still in its early stages and faces challenges due to the variability of CRC, it shows promise as a potential method for understanding and addressing the disease. This review examined the current evidence supporting genetic and epigenetic biomarkers for screening and diagnosis. In addition, we also discussed the feasibility of translating these methodologies into clinical settings. Several markers show promising potential, including the methylation of vimentin (VIM), syndecan-2 (SDC2), and septin 9 (SEPT9). However, their application as screening and diagnostic tools, particularly for early-stage CRC, has not been fully optimized, and their effectiveness needs validation in large, multi-center patient populations. Extensive trials and further investigation are required to translate genetic and epigenetic biomarkers into practical clinical use. biomarkers, diagnostic biomarkers.

Emerging roles of miR-145 in gastrointestinal cancers: A new paradigm

Gastrointestinal (GI) carcinomas are a group of cancers affecting the GI tract and digestive organs, such as the gastric, liver, bile ducts, pancreas, small intestine, esophagus, colon, and rectum. MicroRNAs (miRNAs) are small functional non-coding RNAs (ncRNAs) which are involved in regulating the expression of multiple target genes; mainly at the post-transcriptional level, via complementary binding to their 3'-untranslated region (3'-UTR). Increasing evidence has shown that miRNAs have critical roles in modulating of various physiological and pathological cellular processes and regulating the occurrence and development of human malignancies. Among them, miR-145 is recognized for its anti-oncogenic properties in various cancers, including GI cancers. MiR-145 has been implicated in diverse biological processes of cancers through the regulation of target genes or signaling, including, proliferation, differentiation, tumorigenesis, angiogenesis, apoptosis, metastasis, and therapy resistance. In this review, we have summarized the role of miR-145 in selected GI cancers and also its downstream molecules and cellular processes targets, which could lead to a better understanding of the miR-145 in these cancers. In conclusion, we reveal the potential diagnostic, prognostic, and therapeutic value of miR-145 in GI cancer, and hope to provide new ideas for its application as a biomarker as well as a therapeutic target for the treatment of these cancer.

A comprehensive insight into the role of small nucleolar RNAs (snoRNAs) and SNHGs in human cancers

Long non-coding RNAs (lncRNAs), which comprise most non-coding RNAs (ncRNAs), have recently become a focus of cancer research. How many functional ncRNAs exist is still a matter of debate. Although insufficient evidence supports that most lncRNAs function as transcriptional by-products, it is widely known that an increasing number of lncRNAs play essential roles in cells. Small nucleolar RNAs (snoRNAs), 60-300 nucleotides in length, have been better studied than long non-coding RNAs (lncRNAs) and are predominantly present in the nucleolus. Most snoRNAs are encoded in introns of protein- and non-protein-coding genes called small nucleolar RNA host genes (SNHGs). In this article, we explore the biology and characteristics of SNHGs and their role in developing human malignancies. In addition, we provide an update on the ability of these snoRNAs to serve as prognostic and diagnostic variables in various forms of cancer.

The interaction between ETS transcription factor family members and microRNAs: A novel approach to cancer therapy

In cancer biology, ETS transcription factors promote tumorigenesis by mediating transcriptional regulation of numerous genes via the conserved ETS DNA-binding domain. MicroRNAs (miRNAs) act as posttranscriptional regulators to regulate various tumor-promoting or tumor-suppressing factors. Interactions between ETS factors and miRNAs regulate complex tumor-promoting and tumor-suppressing networks. This review discusses the progress of ETS factors and miRNAs in cancer research in detail. We focused on characterizing the interaction of the miRNA/ETS axis with competing endogenous RNAs (ceRNAs) and its regulation in posttranslational modifications (PTMs) and the tumor microenvironment (TME). Finally, we explore the prospect of ETS factors and miRNAs in therapeutic intervention. Generally, interactions between ETS factors and miRNAs provide fresh perspectives into tumorigenesis and development and novel therapeutic approaches for malignant tumors.

LncRNA SNHG3 Facilitates the Malignant Phenotype of Cholangiocarcinoma Cells via the miR-3173-5p/ERG Axis

BACKGROUND

Long noncoding RNA (lncRNA) small nucleolar RNA host gene 3 (SNHG3) is an oncogenic lncRNA that has been reported in many cancers, but the role of SNHG3 in cholangiocarcinoma (CCA) remains largely unknown. Bioinformatic analysis revealed a regulatory relationship among SNHG3, miR-3173-5p, and ERG. miR-3173-5p is a tumour suppressive miRNA, while ERG is an oncogene. In the present study, we focused on the regulatory effects and molecular mechanisms of SNHG3 in CCA.

METHOD

The expression of SNHG3 and miR-3173-5p was evaluated using qRT-PCR analysis. Knockdown of SNHG3 was achieved by shRNA. Cell viability was assessed by MTT assay. Migration and invasion were determined by Transwell assay. Flow cytometry was used to assess cell apoptosis. Western blots were applied to quantify protein levels. Furthermore, using RNA pulldown and dual luciferase assays, the interactions between SNHG3 and miR-3173-5p and between miR-3173-5p and ERG in CCA cells were validated.

RESULTS

SNHG3 was significantly upregulated in CCA cells compared with normal human intrahepatic biliary epithelial cells. Knockdown of SNHG3 inhibited the proliferation and migration of CCA cells. Mechanistically, SNHG3-sponged miR-3173-5p, thus releasing the repression of ERG by miR-3173-5p. Rescue experiments showed that the miR-3173-5p/ERG axis mediated the oncogenic effect of SNHG3.

CONCLUSION

Taken together, our data suggest that SNHG3 is a pleiotropic oncogenic lncRNA in CCA. Knockdown of SNHG3 expression suppressed malignant phenotypes in CCA cells via the miR-3173-5p/ERG axis.

MicroRNA-934 promotes colorectal cancer cell proliferation by directly targeting Dickkopf-related protein 2

Increasing evidence demonstrates that dysregulation of microRNAs (miRNAs/miRs) is implicated in the development of colorectal cancer. However, the biological functions of several differentially expressed miRNAs remain unknown. In the present study, a bioinformatic analysis of a previously published microarray data and reverse transcription-quantitative PCR analysis demonstrated that miR-934 expression was upregulated in colorectal cancer samples collected from patients. Mechanistically, Dickkopf-related protein 2 (DDK2) was identified as a novel target gene of miR-934 in colorectal cancer cells. Knockdown of DDK2 reversed the inactivation of Wnt signaling pathway induced using miR-934 inhibitor in colorectal cancer cells. In addition, DDK2 silencing reversed miR-934 inhibitor-induced cell proliferation inhibition and elevation of cell apoptosis. The results demonstrated that DDK2 mRNA expression was negatively associated with miR-934 expression in colorectal tumors. Collectively, the results of the present study demonstrated that the miR-934/DDK2 axis regulated colorectal cancer cell proliferation, suggesting that miR-934 may be a biomarker for patients with colorectal cancer.

The emerging role of long noncoding RNAs in esophageal carcinoma: from underlying mechanisms to clinical implications

Long noncoding RNAs (lncRNAs), a type of transcriptional product more than 200 nucleotides in length, have emerged as crucial regulators in human cancers. Accumulating data have recently indicated relationships between lncRNAs and esophageal carcinoma (EC). Of note, lncRNAs act as decoys/sponges, scaffolds, guides, and signals to regulate the expression of oncogenes or tumor suppressors at epigenetic, post-transcriptional, and protein levels, through which they exert their unique EC-driving or EC-suppressive functions. Moreover, the features of EC-related lncRNAs have been gradually exploited for developing novel diagnostic and therapeutic strategies in clinical scenarios. LncRNAs have the potential to be used as diagnostic and prognostic indicators individually or in combination with other clinical variables. Beyond these, although the time is not yet ripe, therapeutically targeting EC-related lncRNAs via gene editing, antisense oligonucleotides, RNA interference, and small molecules is likely one of the most promising therapeutic strategies for the next generation of cancer treatment. Herein, we focus on summarizing EC-driving/suppressive lncRNAs, as well as discussing their different features regarding expression profiles, modes of action, and oncological effects. Moreover, we further discuss current challenges and future developing possibilities of capitalizing on lncRNAs for EC early diagnosis and treatment.

Regulation of Hedgehog Signaling by miRNAs and Nanoformulations: A Possible Therapeutic Solution for Colorectal Cancer

Hedgehog (Hh) signaling aberrations trigger differentiation and proliferation in colorectal cancer (CRC). However, the current approaches which inhibit this vital cellular pathway provoke some side effects. Therefore, it is necessary to look for new therapeutic options. MicroRNAs are small molecules that modulate expression of the target genes and can be utilized as a potential therapeutic option for CRC. On the other hand, nanoformulations have been implemented in the treatment of plethora of diseases. Owing to their excessive bioavailability, limited cytotoxicity and high specificity, nanoparticles may be considered as an alternative drug delivery platform for the Hh signaling mediated CRC. This article reviews the Hh signaling and its involvement in CRC with focus on miRNAs, nanoformulations as potential diagnostic/prognostic and therapeutics for CRC.

Use of miR‑145 and testicular nuclear receptor 4 inhibition to reduce chemoresistance to docetaxel in prostate cancer

The human testicular nuclear receptor 4 (TR4) is a critical regulatory gene for the progression of prostate cancer (PCa). Although it has been revealed that TR4 causes chemoresistance in PCa via the activation of octamer-binding transcription factor 4 (OCT4), the detailed mechanism remains unexplored. In the present study, it was revealed that inhibition of TR4 by shRNA in PCa enhanced the sensitivity to docetaxel in vitro and in vivo. TR4 induced the downregulation of miR-145 by directly binding it to the promoter of miR-145, which was confirmed by chromatin immunoprecipitation analysis and luciferase assay. The overexpression of miR-145 suppressed both the chemoresistance and the expression of OCT4 mRNA and protein. Additionally, the TR4 shRNA mediated re-sensitization to docetaxel, along with the downregulated expression of OCT4, were reversed by the concurrent inhibition of miR-145. The luciferase assay revealed that the activity of the wild-type OCT4 3′ untranslated region reporter was suppressed. This suppression diminished when the miR-145 response element mutated. These findings suggest an undescribed regulatory pathway in PCa, by which TR4 directly suppressed the expression of miR-145, thereby inhibiting its direct target OCT4, leading to the promotion of chemoresistance in PCa.

MicroRNA Expression and Correlation with mRNA Levels of Colorectal Cancer-Related Genes

INTRODUCTION

MicroRNAs (miRNAs), as a family of non-coding RNAs, have opened a new window in cancer biology and transcriptome. It has been revealed that miRNAs post-transcriptionally regulate the gene expression and involve in colorectal cancer (CRC) development and progression. Our aim was to examine the differential expression of miRNAs in a CRC and to correlate their expression levels with mRNA levels of CRC-related genes (K-ras, APC, p53).

MATERIALS AND METHODS

Seventy-two colorectal tumor tissues from patients with newly diagnosed CRC and 72 matched normal adjacent tissues were analyzed. Relative expression of seven CRC-related miRNAs (miR-21, miR-31, miR-20a, miR-133b, and miR-145, miR-135b and let-7g) and three CRC-related genes (K-ras, APC, p53) was detected using the SYBR Green quantitative real-time PCR technique. The correlation between gene expression levels and clinicopathological features was evaluated.

RESULTS

Our results showed a significant difference between the two groups for the expression level of miR-21, miR-31, miR-145, and miR-20a (P < 0.001). Also, a significant difference between the two groups for the expression level of K-ras was found (P < 0.001). Further analysis revealed an inverse significant correlation between miR-145 and K-ras (R² = 0.662, P < 0.001), while a positive correlation was observed between miR-21 and K-ras (R² = 0.732, P < 0.001).

CONCLUSION

Dysregulation of miRNAs and correlation with molecular signaling pathways designated a biological role for miRNAs in various cellular mechanisms underlying CRC. On the other hand, the pattern of miRNAs expression and its correlation with transcriptional status are helpful to discovery biomarkers and design therapeutics for CRC.

miRNA Clusters with Down-Regulated Expression in Human Colorectal Cancer and Their Regulation

Regulation of microRNA (miRNA) expression has been extensively studied with respect to colorectal cancer (CRC), since CRC is one of the leading causes of cancer mortality worldwide. Transcriptional control of miRNAs creating clusters can be, to some extent, estimated from cluster position on a chromosome. Levels of miRNAs are also controlled by miRNAs "sponging" by long non-coding RNAs (ncRNAs). Both types of miRNA regulation strongly influence their function. We focused on clusters of miRNAs found to be down-regulated in CRC, containing miR-1, let-7, miR-15, miR-16, miR-99, miR-100, miR-125, miR-133, miR-143, miR-145, miR-192, miR-194, miR-195, miR-206, miR-215, miR-302, miR-367 and miR-497 and analysed their genome position, regulation and functions. Only evidence provided with the use of CRC in vivo and/or in vitro models was taken into consideration. Comprehensive research revealed that down-regulated miRNA clusters in CRC are mostly located in a gene intron and, in a majority of cases, miRNA clusters possess cluster-specific transcriptional regulation. For all selected clusters, regulation mediated by long ncRNA was experimentally demonstrated in CRC, at least in one cluster member. Oncostatic functions were predominantly linked with the reviewed miRNAs, and their high expression was usually associated with better survival. These findings implicate the potential of down-regulated clusters in CRC to become promising multi-targets for therapeutic manipulation.

Decreased miR-200b-3p in cancer cells leads to angiogenesis in HCC by enhancing endothelial ERG expression

Transcription factor ERG (erythroblast transformation-specific (ETS)-related gene) is essential in endothelial differentiation and angiogenesis, in which microRNA (miR)-200b-3p targeting site is expected by miRNA target prediction database. miR-200b is known decreased in hepatocellular carcinoma (HCC), however, the functional relation between ERG and miR-200b-3p, originating from pre-miR-200b, in HCC angiogenesis remains unclear. We investigated whether hepatocyte-derived miR-200b-3p governs angiogenesis in HCC by targeting endothelial ERG. Levels of miR-200b-3p in HCC tissues were significantly lower than those in adjacent non-HCC tissues. Poorly differentiated HCC cell line expressed lower level of miR-200b-3p compared to well-differentiated HCC cell lines. The numbers of ERG-positive endothelial cells were higher in HCC tissues than in adjacent non-HCC tissues. There was a negative correlation between the number of ERG-positive cells and miR-200b-3p expression in HCC tissues. Culture supernatants of HCC cell lines with miR-200b-3p-overexpression reduced cell migration, proliferation and tube forming capacity in endothelial cells relative to the control, while those with miR-200b-3p-inhibition augmented the responses. Exosomes isolated from HCC culture supernatants with miR-200b-3p overexpression suppressed endothelial ERG expression. These results suggest that exosomal miR-200b-3p from hepatocytes suppresses endothelial ERG expression, and decreased miR-200b-3p in cancer cells promotes angiogenesis in HCC tissues by enhancing endothelial ERG expression.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

MicroRNA‑3651 promotes colorectal cancer cell proliferation through directly repressing T‑box transcription factor 1

Colorectal cancer is a commonly diagnosed gastrointestinal malignancy worldwide with a high mortality rate. Accumulating evidence has indicated that the expression of a number of microRNAs (miRNAs) is associated with the development of colorectal cancer. However, the precise molecular mechanism of these miRNAs in regulating cancer progression is yet to be determined. In the present study, miR‑3651 was demonstrated to be overexpressed in colorectal cancer tissues compared with normal tissues, and to be associated with the tumor‑node‑metastasis stage. The downregulation of miR‑3651 was found to induce growth arrest and apoptosis in colorectal cancer cells. In addition, western blot analysis demonstrated that the downregulation of miR‑3651 inactivated PI3K/AKT and MAPK/ERK signaling in colorectal cancer cells. Bioinformatics analysis predicted T‑box transcription factor 1 (TBX1) as a potential target gene of miR‑3651, and a dual‑luciferase reporter assay confirmed that TBX1 was directly repressed by miR‑3651. The results of the current study also indicated that TBX1 was associated with the miR‑3651 mediated activation of oncogenic signaling and colorectal cancer cell proliferation. In conclusion, the results of the current study revealed the oncogenic potential of miR‑3651 in colorectal cancer.

In silico identification of microRNAs as candidate colorectal cancer biomarkers

The involvement of microRNA in cancers plays a significant role in their pathogenesis. Specific expressions of these non-coding RNAs also serve as biomarkers for early colorectal cancer diagnosis, but their laboratory/molecular identification is challenging and expensive. The aim of this study was to identify potential microRNAs for colorectal cancer diagnosis using in silico approach. Sequence similarity search was employed to obtain the candidate microRNA from the datasets, and three target prediction software were employed to determine their target genes. To determine the involvement of these microRNAs in colorectal cancer, the microRNA gene list obtained was used alongside with colorectal cancer expressed genes from gbCRC and CoReCG databases for gene intersection analysis. The involvement of these genes in the cancer subtype was further strengthened with the DAVID database. KEGG and Gene Ontology were used for the pathway and functional analysis, while STRING was employed for the interactions of protein network and further visualized by Cytoscape. The cBioPortal database was used to prioritize the target genes; prognostic and expression analysis were finally performed on the candidate microRNAs and the prioritized targets. This study, therefore, identified five candidate microRNAs, two hub genes (CTNNB1 and epidermal growth factor receptor), and seven significant target genes associated with colorectal cancer. The molecular validation studies are ongoing to ascertain the biological fitness of these findings.

miR-33a inhibits cell growth in renal cancer by downregulation of MDM4 expression

Background

MicroRNA‐33a (miR‐33a) plays the role of the tumor suppressor gene by regulating the expression level of downstream genes. However, the effects of miR‐33a in renal cell cancer (RCC) remain unknown. Our study was designed to investigate the expression level and potential function of miR‐33a in RCC.

Methods

RT‐qPCR was applied to measure the levels of miR‐33a in RCC tissues and cell lines. Western blotting and luciferase reporter assay were used to detect the relationship between miR‐33a and Mouse double minute 4 (MDM4) in RCC cells. CCK‐8 and flow cytometry were applied to detected cell viability and cell cycle. Animal models and TUNEL assay were applied to detect the effect of miR‐33a on the growth of RCC and cell apoptosis.

Results

We found that the levels of miR‐33a were significantly decreased in RCC tissues and cell lines. Moreover, the low expression of miR‐33a in RCC patients indicated a shorter overall survival (OS). Notably, MDM4 as a direct target of miR‐33a in RCC, the expression level of MDM4 was significantly increased in RCC cells group than the control group. Furthermore, miR‐33a overexpression significantly inhibited RCC cells growth than the control group, while the inhibitory effects of miR‐33a were reversed upon the overexpression of MDM4. Luciferase reporter assays showed that there was a direct interaction between miR‐33a and 3′ UTR of MDM4 mRNA. In vivo, tumor volumes and weight were significantly decreased in the transfected miR‐33a mimics group than the control group.

Conclusion

Taken together, our study indicates that miR‐33a inhibits RCC cell growth by targeting MDM4.

Circular RNA PVT1 promotes metastasis via miR-145 sponging in CRC

Circular RNAs (circRNAs) are a class of covalently closed non-coding RNAs and are widely involved in various cancers including colorectal cancer (CRC). Circular RNA PVT1 (circPVT1) was reported in several malignancies but the role it plays in CRC remains unclear. In our current research, we focused on the expression and function of circPVT1) works in CRC. We found that circPVT1 was upregulated in CRC. Also, we illustrated that the upregulated circPVT1 was closely correlated with poor prognosis and bad clinicopathological features of patients with CRC. Through a loss of function experiment, we showed that a downregulation of circPVT1 suppressed CRC cells metastasis. Through online prediction, we found that circPVT1 had a microRNA response element (MRE) for miR-145. Additionally, we demonstrated that miR-145 was downregulated in CRC. Even further, we showed that miR-145 was involved in circPVT1 mediated facilitation of CRC metastasis. In a further mechanical study, we demonstrated that circPVT1 could target miR-145. Lastly, we revealed that the metastasis-promoting role of circPVT1 in CRC was partially achieved via miR-145 sponging. In brief, the findings of the present study illustrated that circPVT1, working as an oncogene, promotes metastasis via miR-145 sponging in CRC. CircPVT1/miR-145 axial might be a novel point in targeting treatment of CRC.

Genetic and molecular origins of colorectal Cancer among the Iranians: an update

BACKGROUND

Colorectal cancer (CRC) is one the leading causes of cancer related deaths among Iranians. Despite the various progresses in new therapeutic methods, it has still a low rate of survival. This high ratio of mortality is mainly related to the late diagnosis, in which the patients refer for treatment in advanced stages of tumor. MAIN BODY: colorectal cancer progression is largely associated with molecular and genetic bases. Although Iran has a high ratio of CRC mortality, there is not an efficient genetic panel for detection and prognosis. Therefore, it is critical to introduce new diagnostic markers with ability to detect in early stages.

CONCLUSION

Present review summarizes all of the genetic and epigenetic factors which are reported in CRC until now among the Iranian patients to pave the way of incorporation of new ethnic specific markers into the clinical practice and development of new targeted therapeutic methods.

Epigenetic Regulation by lncRNAs: An Overview Focused on UCA1 in Colorectal Cancer

Colorectal cancers have become the second leading cause of cancer-related deaths. In particular, acquired chemoresistance and metastatic lesions occurring in colorectal cancer are a major challenge for chemotherapy treatment. Accumulating evidence shows that long non-coding (lncRNAs) are involved in the initiation, progression, and metastasis of cancer. We here discuss the epigenetic mechanisms through which lncRNAs regulate gene expression in cancer cells. In the second part of this review, we focus on the role of lncRNA Urothelial Cancer Associated 1 (UCA1) to integrate research in different types of cancer in order to decipher its putative function and mechanism of regulation in colorectal cancer cells. UCA1 is highly expressed in cancer cells and mediates transcriptional regulation on an epigenetic level through the interaction with chromatin modifiers, by direct regulation via chromatin looping and/or by sponging the action of a diversity of miRNAs. Furthermore, we discuss the role of UCA1 in the regulation of cell cycle progression and its relation to chemoresistance in colorectal cancer cells.

Regulatory mechanisms of miR-145 expression and the importance of its function in cancer metastasis

MicroRNAs are post-transcriptional mediators of gene expression and regulation, which play influential roles in tumorigenesis and cancer metastasis. The expression of tumor suppressor miR-145 is reduced in various cancer cell lines, containing both solid tumors and blood malignancies. However, the responsible mechanisms of its down-regulation are a complicated network. miR-145 is potentially able to inhbit tumor cell metastasis by targeting of multiple oncogenes, including MUC1, FSCN1, Vimentin, Cadherin, Fibronectin, Metadherin, GOLM1, ARF6, SMAD3, MMP11, Snail1, ZEB1/2, HIF-1α and Rock-1. This distinctive role of miR-145 in the regulation of metastasis-related gene expression may introduce miR-145 as an ideal candidate for controlling of cancer metastasis by miRNA replacement therapy. The present review aims to discuss the current understanding of the different aspects of molecular mechanisms of miR-145 regulation as well as its role in r metastasis regulation.

The effects of lncRNA MALAT1 on proliferation, invasion and migration in colorectal cancer through regulating SOX9

Background

For the study, we determine the potential biomarkers and uncover the regulatory mechanisms of lncRNA MALAT1 / miR-145 / SOX9 axis on the abilities of cell growth and cell metastasis of colorectal cancer.

Methods

Previously published dataset GSE18105 from GEO database was used for microarray analysis to identify differential-expressed lncRNAs and mRNAs. The miRNA which had targeted relationships with both lncRNA and mRNA was predicted using miRCode and Targetscan. The association between lncRNA and miRNA, miRNA and mRNA was verified using dual-luciferase reporter assay.

Expression levels of lncRNA MALAT1, miR-145 and SOX9 were examined by quantitative RT-PCR analysis. The cell viability of two cancer cell lines was compared by CCK-8 assay. Colony formation was hired to detected cell proliferation. The cell cycle distribution and apoptotic cell rate were conducted by flow cytometry assay. Wound healing as well as transwell assay were compare the cell migration and cell invasion respectively among groups. The effect of MALAT1 on colorectal cancer in vivo was constructed by xenograft model.

Results

Significantly dysregulated lncRNAs and mRNAs were identified by microarray analysis. By experimental verification, MALAT1 and SOX9 were expressed in a high percentage of colorectal cancer tumors and cells, while miR-145 was in a low expression. We also identified miR-145 as a target of MALAT1 and SOX9. MALAT1 played a role in regulating cancer process by functioning as a competing endogenous RNA. Silencing MALAT1 could effectively decrease the expression level of SOX9, thus suppress cell viability and metastasis. Down-regulated MALAT1 could induce resistance of G1 phase in cell cycle, and facilitation of colorectal cancer cell apoptosis. Nude mice injected with cells transfected with si-MALAT1 had smaller tumor on size and weight.

Conclusions

The regulatory function of lncRNA MALAT1 / miR-145 / SOX9 axis was revealed in colorectal cancer based on bioinformatics analysis. LncRNA MALAT1 could facilitate colorectal cancer cell proliferation, invasion and migration by down-regulating miR-145 and up-regulating SOX9. LncRNA MALAT1 could suppress cell cycle and apoptosis through MALAT1 / miR-145 / SOX9 axis.

MiR-145 improves macrophage-mediated inflammation through targeting Arf6

PURPOSE

To explore the relationship between miR-145 and ADP ribosylation factor 6 (Arf6) in regulating macrophage-mediated inflammation.

METHODS

THP-1 cells were induced by 160 nM of phorbol 12^-myristate 13-acetate (PMA) for 48 h to differentiate to macrophages and then were treated with LPS (100 ng/ml) for 8 h to simulate chronic metabolic inflammation in vitro. Dual-luciferase reporter assay was performed. MiR-145 siRNA and LV-ARF6-RNAi were used to up or down regulate miR-145 and Arf6 expression in THP-1 cells, respectively. Omental adipose tissue from patients in surgical ward were collected to detect the expression of miR-145, Arf6 and production of proinflammatory cytokines. Patients were divided into three groups according to their body mass index and history of diabetes.

RESULTS

Dual-luciferase reporter assays showed the direct down-regulation of Arf6 by miR-145. Forty-eight-hour-transfection of miR-145 inhibitor resulted in significant increase of Arf6, IL-1beta, TNF-alpha and IL-6 as well as phosphorylation of p65 in NF-kappaB pathway in THP-1 cells, which, inversely, were reversed by overexpressing miR-145. In addition, down-regulation of Arf6 in macrophages reduced expression and secretion of cytokines. Expression of miR-145 was found to be attenuated in the omental adipose tissue of obese patients and diabetics with greater Arf6 expression, confirming the role of miR-145 in regulating macrophage-mediated inflammation targeting Arf6.

CONCLUSIONS

By means of reducing the expression of Arf6 and subsequent signal transduction via NF-kappaB, miR-145 plays a role in inhibiting the secretion of inflammatory factors and then improving the inflammatory status. MiR-145 might be one of the candidates for anti-inflammatory treatment for metabolic diseases.

The Role of MicroRNA Signature as Diagnostic Biomarkers in Different Clinical Stages of Colorectal Cancer

OBJECTIVES

Colorectal cancer (CRC) is one of the most common cancers and a major cause of cancer-related death worldwide. The early diagnosis of colorectal tumors is one of the most important challenges in cancer management. MicroRNAs (miRNAs) have provided new insight into CRC development and have been suggested as reliable and stable biomarkers for diagnosis and prognosis. This study's objective was to analyze the differential expression of miRNAs at differentstages of CRC searching for possible correlation with clinicopathological features to examine their potential value as diagnostic biomarkers.

MATERIALS AND METHODS

In this case-control study, plasma and matched tissue samples were collected from 74 CRC patients at stage II-IV as well as blood samples from 32 healthy controls. After exhaustive study of the current literature, eight miRNAs including miR-200c, 20a, 21, 31,135b, 133b,145 and let-7g were selected. The expression level of the miRNAs was assayed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Statistical analysis, including t test , Mann-Whitney U, Kruskall-Wallis tests and receiver operating characteristic (ROC) curve was applied, where needed.

RESULTS

Significantly elevated levels of miR-21, miR-31, miR-20a, miR-135b, and decreased levels of miR- 200c, miR-145 and let-7 g were detected in both plasma and matched tissue samples compared to the healthy group (P<0.05). However, no significant differences were observed in the expression level of plasma and tissue miR-133b (P>0.05). ROC for tissue miRNAs showed an area under the ROC curve (AUC) of 0.98 and P<0.001 for miR-21, 0.91 and P<0.001 for miR-135b, 0.91 and P<0.001 for miR-31, and 0.92 and P<0.001 for miR-20a.

CONCLUSIONS

Our results indicate that the expression levels of microRNAs are systematically altered in CRC tissue and plasma. In conclusion, detection of miR-21, miR-135b, miR-31 and miR-20a levels in the tissue might be helpful to illuminate the molecular mechanisms underlying CRC carcinogenesis and serve as tumor-associated biomarkers for diagnosis.

miRNA-145 is associated with spontaneous hypertension by targeting SLC7A1

Previous studies have indicated that microRNAs (miRNAs/miRs) may participate in the pathogenesis of hypertension. miR-145 has been demonstrated to serve important roles in the development of numerous cardiovascular diseases. However, the specific role of miR-145 in hypertension remains unclear. The present study aimed to investigate the role of miR-145 in spontaneously hypertensive rats (SHR) and rat vascular endothelial cells (RVECs). The results of the present study demonstrated that in the SHR group miR-145 expression was significantly upregulated in the thoracic aorta compared with the control group. Furthermore, a significant decrease in nitric oxide (NO) content was observed in the SHR group compared with the control rats. In RVECs, silencing miR-145 induced a significant increase in the expression of solute carrier family 7 member 1 (SLC7A1) and phosphorylated endothelial nitric oxide synthase, and a dual-luciferase reporter assay confirmed that SLC7A1 is a direct target of miR-145. The results of the present study indicate that miR-145 functions as a key mediator in the pathogenesis of hypertension via targeting SLC7A1, which suggests that miR-145 is a potential target for the treatment of hypertension.

MiR-145 inhibits the epithelial-to-mesenchymal transition via targeting ADAM19 in human glioblastoma

In recent years, increasing studies demonstrated that miR-145 plays a tumor suppressor role in many human cancers. In the present study, we evaluated the expression of miR-145 and A Disintegrin and Metalloproteinase 19 (ADAM19) in glioblastoma multiforme (GBM) tissues and cells. Furthermore, we investigated the mechanisms underlying miR-145/ADAM19-induced GBM biology. Here, we found that miR-145 expression was down-regulated, while ADAM19 expression was up-regulated in GBM tissues and cells. Moreover, miR-145 mimics repressed U87 and U251 cell proliferation, migration and invasion. miR-145 mimics also inhibited the epithelial-to-mesenchymal transition (EMT) of U87 and U251 cells. Mechanically, the 3′ untranslated region (3′-UTR) of ADAM19 mRNA was a direct target for miR-145. In addition, ADAM19 over-expression also partially abrogated miR-145-inhibited EMT. In conclusion, this work suggested that high miR-145 expression inhibited EMT of GBM cells by targeting ADAM19. Thus miR-145/ADAM19 can be suggested as a novel target for GBM patients.

The lincRNA-ROR/miR-145 axis promotes invasion and metastasis in hepatocellular carcinoma via induction of epithelial-mesenchymal transition by targeting ZEB2

Emerging evidence show that long noncoding RNAs (lncRNAs) play critical roles in tumor development. LincRNA-ROR (linc-ROR) is known to promote tumor progress in several human cancers, including hepatocellular carcinoma (HCC). Nevertheless, the roles of linc-ROR in HCC metastasis and its underlying mechanisms remain fully unclear. In the present study, we showed that linc-ROR was upregulated in HCC tissues and high linc-ROR expression level predicted poor prognosis. Functionally, linc-ROR significantly induced epithelial-mesenchymal transition (EMT), and increased in vitro invasion and in vivo metastasis of HCC cells. Mechanistically, linc-ROR acted as a sponge for miR-145 to de-repress the expression of target gene ZEB2, thereby inducing EMT and promoting HCC metastasis. Collectively, our research indicates the potential of linc-ROR as a vital therapeutic target for the treatment of aggressive and metastatic HCC.

Clinical value of miR-145-5p in NSCLC and potential molecular mechanism exploration: A retrospective study based on GEO, qRT-PCR, and TCGA data

MicroRNAs have been reported to be involved in various biological processes. Here, we performed a systematic analysis to explore the clinical value and potential molecular mechanism of miR-145-5p in non-small cell lung cancer. First, a meta-analysis was performed with eligible literature, followed by microRNA microarrays in the Gene Expression Omnibus database, to verify the diagnostic and prognostic values of miR-145-5p. A cohort of 125 clinical paired non-small cell lung cancer samples was next used to detect the level of miR-145-5p and to explore the relationship of miR-145-5p with clinicopathological parameters. The Cancer Genome Atlas database was additionally applied to investigate the role of miR-145-5p in non-small cell lung cancer. The potential targets of miR-145-5p were predicted using 12 online prediction databases to explore the prospective molecular mechanism of miR-145-5p in non-small cell lung cancer. The expression of miR-145-5p in non-small cell lung cancer was significantly lower than that in healthy tissues. And miR-145-5p tended to show better diagnostic performance in lung squamous cell carcinoma than in lung adenocarcinoma. Furthermore, the expression of miR-145-5p was closely associated with lymph node metastasis in non-small cell lung cancer. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the target genes were mainly enriched with enzyme-linked receptor protein signaling pathways, SH3 domain binding, cell leading edge, and adherens junction. The protein-protein interaction network showed that eight hub genes (SMAD4, SMAD2, IRS1, FOXO1, ERBB4, NRAS, ACTB, and ACTG1) might be the key target genes of miR-145-5p in non-small cell lung cancer. The information we obtained might offer new perspectives for clinical diagnosis and treatment for non-small cell lung cancer.