miR-493-5p attenuates the invasiveness and tumorigenicity in human breast cancer by targeting FUT4

Death-associated protein 3 in cancer-discrepant roles of DAP3 in tumours and molecular mechanisms

Cancer, ranks as the secondary cause of death, is a group of diseases that are characterized by uncontrolled tumor growth and distant metastasis, leading to increased mortality year-on-year. To date, targeted therapy to intercept the aberrant proliferation and invasion is crucial for clinical anticancer treatment, however, mutant expression of target genes often leads to drug resistance. Therefore, it is essential to identify more molecules that can be targeted to facilitate combined therapy. Previous studies showed that death associated protein 3 (DAP3) exerts a pivotal role in regulating apoptosis signaling of tumors, meanwhile, aberrant DAP3 expression is associated with the tumorigenesis and disease progression of various cancers. This review provides an overview of the molecule structure of DAP3 and the discrepant roles played by DAP3 in various types of tumors. Considering the molecular mechanism of DAP3-regulated cancer development, new potential treatment strategies might be developed in the future.

ER Negative Breast Cancer and miRNA: There Is More to Decipher Than What the Pathologist Can See!

Breast cancer (BC), the most prevalent cancer in women, is a heterogenous disease. Despite advancements in BC diagnosis, prognosis, and therapeutics, survival rates have drastically decreased in the metastatic setting. Therefore, BC still remains a medical challenge. The evolution of high-throughput technology has highlighted gaps in the classification system of BCs. Of particular interest is the notorious triple negative BC, which was recounted as being heterogenous itself and it overlaps with distinct subtypes, namely molecular apocrine (MA) and luminal androgen (LAR) BCs. These subtypes are, even today, still misdiagnosed and poorly treated. As such, researchers and clinicians have been looking for ways through which to refine BC classification in order to properly understand the initiation, development, progression, and the responses to the treatment of BCs. One tool is biomarkers and, specifically, microRNA (miRNA), which are highly reported as associated with BC carcinogenesis. In this review, the diverse roles of miRNA in estrogen receptor negative (ER-) and androgen receptor positive (AR+) BC are depicted. While highlighting their oncogenic and tumor suppressor functions in tumor progression, we will discuss their diagnostic, prognostic, and predictive biomarker potentials, as well as their drug sensitivity/resistance activity. The association of several miRNAs in the KEGG-reported pathways that are related to ER-BC carcinogenesis is presented. The identification and verification of accurate miRNA panels is a cornerstone for tackling BC classification setbacks, as is also the deciphering of the carcinogenesis regulators of ER - AR + BC.

Effect of miR-493-5p on proliferation and differentiation of myoblast by targeting ANKRD17

The hypertrophy and conversion of postnatal muscle fibers largely determine the yield and quality of meat, which is closely related to the economic value of pigs. MicroRNA (miRNA), as a kind of endogenous noncoding RNA molecule, is widely involved in myogenesis of livestock and poultry. The longissimus dorsi tissues of Lantang pigs at 1 and 90 days (LT1D and LT90D) were collected and profiled by miRNA-seq. We found 1871 and 1729 miRNA candidates in LT1D and LT90D samples, and 794 miRNAs were shared. We identified 16 differentially expressed miRNAs between two tested groups and explored the function of miR-493-5p inmyogenesis. The miR-493-5p promoted the proliferation and inhibited the differentiation of myoblasts. Using GO and KEGG analyses of 164 target genes of miR-493-5p, we found that ATP2A2, PPP3CA, KLF15, MED28, and ANKRD17 genes were related to muscle development. RT-qPCR detection showed that the expression level of ANKRD17 was highly expressed in LT1D libraries, and the double luciferase report test preliminarily proved that miR-493-5p and ANKRD17 have a directly targeting relationship. We established miRNA profiles for the longissimus dorsi tissues of 1-day-old and 90-day-old Lantang pigs and found that miR-493-5p was differentially expressed and associated with myogenesis by targeting ANKRD17 gene. Our results should serve as a reference for future studies on pork quality.

LINC00324 promotes cell proliferation and metastasis of esophageal squamous cell carcinoma through sponging miR-493-5p via MAPK signaling pathway

Long non-coding RNAs have been demonstrated to promote proliferation and metastasis via regulating the miRNA/mRNA regulatory axis in various malignancies. Based on our preliminary study, we investigated the mechanism of LINC00324 through miR-493-5p/MAPK1 in esophageal squamous cell carcinoma (ESCC) pathogenesis. Herein, we confirmed that LINC00324 is significantly upregulated in ESCC primary cells and esophageal squamous cell carcinoma cell line KYSE-70. Silencing of LINC00324 modulates cell proliferation markers, p21, p27, c-Myc, and Cyclin D1 and epithelial-to-mesenchymal transition markers, slug, snail, ZEB1, vimentin, ZO-1, and E-cadherin protein expression in ESCC. Through bioinformatics and dual luciferase reporter assays, we identified miR-493-5p as the direct target molecule of LINC00324. We further revealed that LINC00324 negatively regulates miR-493-5p expression in ESCC. Moreover, our multiple gain-and loss-of-functional experiments proved that a combination of miR-493-5p and LINC00324 significantly rescued ESCC cell proliferation and metastatic phenotypes. Mechanistically, LINC00324 promotes ESCC pathogenesis by acting as a competing endogenous RNA and sponges miR-493-5p activity thereby activating MAPK1 during ESCC progression. We believe that targeting LINC00324 /miR-493-5p/MAPK1 axis may provide new therapeutic avenues for ESCC.

New progress in the role of microRNAs in the diagnosis and prognosis of triple negative breast cancer

Triple negative breast cancer is distinguished by its high malignancy, aggressive invasion, rapid progression, easy recurrence, and distant metastases. Additionally, it has a poor prognosis, a high mortality, and is unresponsive to conventional endocrine and targeted therapy, making it a challenging problem for breast cancer treatment and a hotspot for scientific research. Recent research has revealed that certain miRNA can directly or indirectly affect the occurrence, progress and recurrence of TNBC. Their expression levels have a significant impact on TNBC diagnosis, treatment and prognosis. Some miRNAs can serve as biomarkers for TNBC diagnosis and prognosis. This article summarizes the progress of miRNA research in TNBC, discusses their roles in the occurrence, invasion, metastasis, prognosis, and chemotherapy of TNBC, and proposes a treatment strategy for TNBC by interfering with miRNA expression levels.

The Mutual Relationship between Glycosylation and Non-Coding RNAs in Cancer and Other Physio-Pathological Conditions

Glycosylation, which consists of the enzymatic addition of sugars to proteins and lipids, is one of the most important post-co-synthetic modifications of these molecules, profoundly affecting their activity. Although the presence of carbohydrate chains is crucial for fine-tuning the interactions between cells and molecules, glycosylation is an intrinsically stochastic process regulated by the relative abundance of biosynthetic (glycosyltransferases) and catabolic (glycosidases) enzymes, as well as sugar carriers and other molecules. Non-coding RNAs, which include microRNAs, long non-coding RNAs and circRNAs, establish a complex network of reciprocally interacting molecules whose final goal is the regulation of mRNA expression. Likewise, these interactions are stochastically regulated by ncRNA abundance. Thus, while protein sequence is deterministically dictated by the DNA/RNA/protein axis, protein abundance and activity are regulated by two stochastic processes acting, respectively, before and after the biosynthesis of the protein axis. Consequently, the worlds of glycosylation and ncRNA are closely interconnected and mutually interacting. In this paper, we will extensively review the many faces of the ncRNA-glycosylation interplay in cancer and other physio-pathological conditions.

Differential expression profiles of miRNA in the serum of sarcopenic rats

As the geriatric population and life expectancy increase, the interest in preventing geriatric diseases, such as sarcopenia, is increasing. However, the causes of sarcopenia are unclear, and current diagnostic methods for sarcopenia are unreliable. We hypothesized that the changes in the expression of certain miRNAs may be associated with the pathophysiology of sarcopenia. Herein, we analyzed the miRNA expression profiles in the blood of young (3-months-old) healthy rats, old sarcopenic (17-months-old) rats, and age-matched (17-months-old) control rats. The changes in miRNA expression levels were analyzed using Bowtie 2 software. A total of 523 miRNAs were detected in the rat serum. Using scatter plots and clustering heatmap data, we found 130 miRNAs that were differentially expressed in sarcopenic rats (>2-fold change) compared to the expression in young healthy and age-matched control rats. With a threshold of >5-fold change, we identified 14 upregulated miRNAs, including rno-miR-133b-3p, rno-miR-133a-3p, rno-miR-133c, rno-miR-208a-3p, and rno-miR434-5p among others in the serum of sarcopenic rats. A protein network map based on these 14 miRNAs identified the genes involved in skeletal muscle differentiation, among which Notch1, Egr2, and Myocd represented major nodes. The data obtained in this study are potentially useful for the early diagnosis of sarcopenia and for the identification of novel therapeutic targets for the treatment and/or prevention of sarcopenia.

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Early diagnosis of sarcopenia and discovery of therapeutic targets are necessary.

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We determined the significantly increased miRNAs in the serum of sarcopenic rats.

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They include rno-miR-133b-3p, 133a-3p, 133c, 208a-3p, and miR434-5p.

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Network mapping from the miRNA expression profiles helps identify target proteins.

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Notch, Egr, and Myocd genes were suggested as targets for sarcopenia treatment.

Circ_VANGL1 affects proliferation, migration, and invasion of colorectal cancer cells by regulating miR-493-5p/FXR1 axis

BACKGROUND

CircRNAs are abnormally expressed in colorectal cancer (CRC) tissues, cell lines, and plasma, and are closely related to the clinical malignant characteristics of CRC. However, the expression and functional mechanism of circ_VANGL1 in CRC are still unclear. We hypothesized that circ_VANGL1 affects the proliferation, migration, and invasion of CRC cells by regulating the miR-493-5p/fragile X-related gene 1 (FXR1) axis.

AIM

To investigate the effect of circ_VANGL1 on the prolife-ration, migration, and invasion of CRC cells and the possible mechanism involved.

METHODS

Western blot was used to detect the expression of FXR1 in CRC tissues and adjacent tissues. RT-qPCR was performed to detect the expression of circ_VANGL1 and miR-493-5p. CRC cells Caco-2 were cultured in vitro and divided into si-circ_VANGL1 group, si-NC group, miR-NC group, miR-493-5p mimic group, and si-circ_VANGL1 + miR-493-5p inhibitor group. CCK-8 and clone formation assays were performed to evaluate the proliferation ability of Caco-2 cells. Transwell assay was employed to evaluate the migration and invasion ability of Caco-2 cells. Dual luciferase reporter assay was used to detect the interaction between RNAs (circ_VANGL1 and miR-493-5p, miR-493-5p, and FXR1).

RESULTS

Compared with tumor adjacent tissues, the relative expression levels of circ_VANGL1 and FXR1 protein in CRC tissue were significantly increased (P < 0.05), but the relative level of miR-493-5p was significantly decreased (P < 0.05). Compared with the si-NC group, the inhibition rate of Caco-2 cells and the relative level of miR-493-5p in the si-circ_VANGL1 group were significantly increased (P < 0.05), but the expression of FXR1 protein, the number of colonies formed, and the migration and invasion ability were significantly reduced (P < 0.05). Compared with the miR-NC group, the inhibition rate of Caco-2 cells in the miR-493-5p mimic group was significantly increased (P < 0.05), but the expression of FXR1 protein, the number of colonies formed, and the migration and invasion ability were significantly reduced (P < 0.05). Circ_VANGL1 directly bound to miR-493-5p. Compared with the si-circ_VANGL1 group, the inhibition rate of Caco-2 cells in the si-circ_VANGL1 + miR-493-5p inhibitor group was significantly reduced (P < 0.05), but the expression of FXR1 protein, the number of colonies formed, and the migration and invasion ability were significantly increased (P < 0.05).

CONCLUSION

Silencing circ_VANGL1 inhibits the proliferation, migration, and invasion of CRC cells by regulating the miR-493-5p/FXR1 axis.

miRNA and lncRNA Expression Networks Modulate Cell Cycle and DNA Repair Inhibition in Senescent Prostate Cells

Cellular senescence is a state of permanent growth arrest that arises once cells reach the limit of their proliferative capacity. It creates an inflammatory microenvironment favouring the initiation and progression of various age-related diseases, including prostate cancer. Non-coding RNAs (ncRNAs) have emerged as important regulators of cellular gene expression. Nonetheless, very little is known about the interplay of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) and how deregulation of ncRNA networks promotes cellular senescence. To investigate this, human prostate epithelial cells were cultured through different passages until senescent, and their RNA was extracted and sequenced using RNA sequencing (RNAseq) and microRNA sequencing (miRNA-seq) miRNAseq. Differential expression (DE) gene analysis was performed to compare senescent and proliferating cells with Limma, miRNA-target interactions with multiMiR, lncRNA-target interactions using TCGA data and network evaluation with miRmapper. We found that miR-335-3p, miR-543 and the lncRNAs H19 and SMIM10L2A all play central roles in the regulation of cell cycle and DNA repair processes. Expression of most genes belonging to these pathways were down-regulated by senescence. Using the concept of network centrality, we determined the top 10 miRNAs and lncRNAs, with miR-335-3p and H19 identified as the biggest hubs for miRNAs and lncRNA respectively. These ncRNAs regulate key genes belonging to pathways involved in cell senescence and prostate cancer demonstrating their central role in these processes and opening the possibility for their use as biomarkers or therapeutic targets to mitigate against prostate ageing and carcinogenesis.

Human microRNA similarity in breast cancer

MicroRNAs (miRNAs) play important roles in a variety of human diseases, including breast cancer. A number of miRNAs are up- and down-regulated in breast cancer. However, little is known about miRNA similarity and similarity network in breast cancer. Here, a collection of 272 breast cancer-associated miRNA precursors (pre-miRNAs) were utilized to calculate similarities of sequences, target genes, pathways and functions and construct a combined similarity network. Well-characterized miRNAs and their similarity network were highlighted. Interestingly, miRNA sequence-dependent similarity networks were not identified in spite of sequence–target gene association. Similarity networks with minimum and maximum number of miRNAs originate from pathway and mature sequence, respectively. The breast cancer-associated miRNAs were divided into seven functional classes (classes I–VII) followed by disease enrichment analysis and novel miRNA-based disease similarities were found. The finding would provide insight into miRNA similarity, similarity network and disease heterogeneity in breast cancer.

Circular RNA circPRKDC promotes tumorigenesis of gastric cancer via modulating insulin receptor substrate 2 (IRS2) and mediating microRNA-493-5p

CircPRKDC has been disclosed to participate in the tumorigenesis of serval tumors, but the regulatory mechanisms of circPRKDC in GC are still unknown. CircPRKDC, miR-493-5p, and insulin receptor substrate 2 (IRS2) levels were tested by RT-qPCR. The epithelial-mesenchymal transition (EMT)-related protein levels were evaluated via western blot. The cell viability, migration and invasion were evaluated through CCK-8 and Transwell assays. Luciferase reporter and RIP assays were employed to confirm the binding ability between miR-493-5p and circPRKDC or IRS2. CircPRKDC was upregulated in GC samples, and circPRKDC silencing restrained GC cell viability, metastasis, and EMT and suppressed GC tumor growth. Besides, miR-493-5p was a target of circPRKDC, and the repressive impact of circPRKDC knockdown on GC development was neutralized by miR-493-5p inhibition. Moreover, miR-493-5p targeted IRS2 and IRS2 addition rescued the effects of circPRKDC depletion on GC progression. Finally, circPRKDC knockdown could regulate IRS2 expression by targeting miR-493-5p. These results elaborated that circPRKDC accelerated GC development via sponging miR-493-5p and increasing IRS2, which might provide novel potential targets for GC treatment.

MiR-493-5p inhibits the malignant development of gliomas via suppressing E2F3-mediated dysfunctions of P53 and PI3K/AKT pathways

BACKGROUND

Gliomas is a major challenge of current medical system, and thousands of people are struggling in the pain of this disease worldwide. In the last decade, the functions of miRNAs have been revealed by many studies, and the intervention on miRNA dysfunctions has been thought as a promising way to counter cancer. MiR-493-5p has been identified as a tumor inhibitor to suppress the progressions of several tumors while its role in gliomas remains unknown. Hence, the study investigated the expression levels of miR-493-5p in glioma tissues and cell lines.

METHODS

CCK-8 assay, transwell assay and flow cytometry assay were used to observe the effects of miR-493-5p on tumor cells. The downstream targets of miR-493-5p were also searched and verified with online databases and dual-luciferase reporter assay. Moreover, the activities of P53 and PI3K/AKT pathways were also explored by western blot to illustrate the regulation mechanism of miR-493-5p on glioma development.

RESULTS

The results showed that miR-493-5p was significantly downregulated in pathological tissues and glioma cell lines, and the increased miR-493-5p effectively inhibited the malignant behavior and promoted the apoptosis of glioma cells.

CONCLUSIONS

E2F3 was confirmed as a target of miR-493-5p, and the effects of miR-493-5p on the phenotype of glioma cells could be partly reversed by E2F3. Besides, it was also found that miR-493-5p could effectively suppress the expression of E2F3 and then improve the dysfunctions of the P53 and PI3K/AKT pathways.

Dexmedetomidine upregulates the expression of miR-493-5p, inhibiting growth and inducing the apoptosis of lung adenocarcinoma cells by targeting RASL11B

Numerous studies have indicated that microRNAs (miRNAs) play critical roles in the development and progression of cancer. However, how changes to the expression levels of miRNAs in response to dexmedetomidine affects the progression of lung cancer remains poorly understood. In this study, we treated the lung adenocarcinoma cell line-A549 with dexmedetomidine and then examined the changes to the expression levels of miRNAs. We found that one of the most significantly upregulated miRNAs was miR-493-5p, which has an important role in the growth and apoptosis of lung adenocarcinoma (LUAD) cells. In addition, bioinformatics searches and luciferase reporter assays revealed that miR-493-5p targets RASL11B, which has a high degree of similarity to RAS. Finally, database searches revealed that RASL11B is associated with survival of LUAD cells. In conclusion, dexmedetomidine causes changes to the expression levels of miRNAs in LUAD, including significant upregulation of miR-493-5p. MiR-493-5p targets RASL11B, thereby inhibiting cell growth and inducing apoptosis in LUAD.

Circ-CSPP1 knockdown suppresses hepatocellular carcinoma progression through miR-493-5p releasing-mediated HMGB1 downregulation

BACKGROUND

Hepatocellular carcinoma (HCC) accounts for over 80% of primary liver cancers and leads to a high death rate. Research on circular RNAs (circRNAs) suggests that circRNAs are promising biomarkers for cancer treatment. This study aimed to explore the function of a novel circRNA (circ-CSPP1) in HCC.

METHODS

Circ-CSPP1 was obtained from the microarray data downloaded from the Gene Expression Omnibus (GEO) database. The expression of circ-CSPP1, miR-493-5p and high mobility group box 1 (HMGB1) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, colony formation ability, migration and invasion were monitored using cell counting kit-8 (CCK-8) assay, colony formation assay, wound healing assay and transwell assay, respectively. The protein levels of CyclinD1, Vimentin, matrix metallopeptidase 9 (MMP-9) and HMGB1 were detected by western blot. Xenograft models were established to investigate the function of circ-CSPP1 in vivo. The association between miR-493-5p and circ-CSPP1 or HMGB1 was predicted by the online tool starBase and ensured by dual-luciferase reporter assay.

RESULTS

The expression of circ-CSPP1 and HMGB1 was elevated, while the expression of miR-493-5p was declined in HCC tissues and cells. Circ-CSPP1 knockdown not only depleted HCC cell proliferation, formation, migration and invasion in vitro but also inhibited tumor growth in vivo. MiR-493-5p was a target of circ-CSPP1, and HMGB1 was a target of miR-493-5p. Rescue experiments presented that miR-493-5p deficiency reversed the effects of circ-CSPP1 knockdown, and HMGB1 overexpression reversed the effects of miR-493-5p restoration. Circ-CSPP1 sponged miR-493-5p to regulate HMGB1 expression.

CONCLUSION

Knockdown of circ-CSPP1 suppressed HCC development both in vitro and in vivo by upregulation of miR-493-5p and downregulation of HMGB1, hinting that circ-CSPP1 participated in HCC pathogenesis.

Lung cancer‑associated transcript 1 facilitates tumorigenesis in laryngeal squamous cell carcinoma through the targeted inhibition of miR‑493

Long non-coding RNAs (lncRNAs) serve important roles in the tumorigenesis of a diverse range of cancer types. The lung cancer-associated transcript 1 (LUCAT1), has been reported to promote the proliferation, migration and invasion of oral squamous cell carcinoma cells. However, the exact role of LUCAT1 in laryngeal squamous cell carcinoma (LSCC) remains to fully understood. The present study aimed to interrogate the role and modulatory mechanism of LUCAT1 in LSCC. Reverse transcription-quantitative PCR and western blotting were used to investigate the expression of LUCAT1 and miR-493, as well as the protein expression of cyclin-dependent kinase 2, cyclin E1, p21, matrix metalloproteinase (MMP)2, MMP9, vascular endothelial growth factor-C, Bcl-2, Bax, cleaved caspase-3 and procaspase-3. Cell Counting Kit-8, flow cytometry, wound healing and Transwell assays were performed to analyze the proliferation, cell cycle, apoptosis levels, and the migratory and invasive abilities, respectively, of the LSCC AMC-HN-8 cell line. In addition, dual-luciferase reporter and ribonucleoprotein immunoprecipitation assays were used to investigate the binding between LUCAT1 and microRNA (miR)-493. The results of the present study revealed that the expression levels of LUCAT1 were upregulated in AMC-HN-8 cells. The genetic knockdown of LUCAT1 expression levels significantly suppressed the cell proliferation, alongside downregulating the expression levels of CDK2 and cyclin E1 and upregulating p21 expression levels. In addition, the knockdown of LUCAT1 inhibited cell migration and invasion, as demonstrated using the wound healing and Transwell assays, respectively. Moreover, LUCAT1 knockdown promoted cell apoptosis and upregulated the expression levels of Bax and cleaved caspase-3, whilst downregulating the expression levels of Bcl-2. Furthermore, LUCAT1 was discovered to directly bind to and inhibit the well-known tumor suppressor, miR-493. Notably, the specific inhibition of miR-493 partly blocked the anticancer effects of LUCAT1 knockdown in AMC-HN-8 cells. In conclusion, these results suggested that LUCAT1 may facilitate tumorigenesis in LSCC through the targeted inhibition of miR-493, which provides evidence for a novel target for the treatment of LSCC.

Sweet Control: MicroRNA Regulation of the Glycome

Glycosylation is a sophisticated informational system that controls specific biological functions at the cellular and organismal level. Dysregulation of glycosylation may underlie some of the most complex and common diseases of the modern era. In the past 5 years, microRNAs have come to the forefront as a critical regulator of the glycome. Herein, we review the current literature on miRNA regulation of glycosylation and how this work may point to a new way to identify the biological importance of glycosylation enzymes.

Circular RNA 103862 Promotes Proliferation and Invasion of Laryngeal Squamous Cell Carcinoma Cells Through the miR-493-5p/GOLM1 Axis

Accumulating evidence suggests that circular RNAs (circRNAs) may be a key contributor to oncogenesis. Yet, the function of circRNAs in laryngeal squamous cell carcinoma (LSCC) is still not clear. In this study, we examined the function of circRNA_103862 in LSCC progression by analyzing the tissue specimens collected from a patient with LSCC by using different LSCC cell models in vitro and an LSCC xenograft model in nude mice. We found that circRNA_103862 was frequently upregulated in the tissues of LSCC and was correlated with metastasis and prognosis of LSCC patients. Furthermore, circRNA_103862 downregulation could reduce proliferation, migration, and invasion ability of LSCC cells. In terms of mechanism exploration, miR-493-5p was sponged by circRNA_103862. Rescue experiments also showed that circRNA_103862 could achieve a carcinogenic effect by regulating miR-493-5p. Moreover, a luciferase reporter analysis showed that Golgi membrane protein 1 (GOLM1) is a downstream effector of miR-493-5p. In conclusion, our data suggested that circRNA_103862 promotes the proliferation of LSCC through targeting the miR-493-5p/GOLM1 axis, and it might serve as a potential prognosis marker and therapy target for LSCC.

Effects of CORO2A on Cell Migration and Proliferation and Its Potential Regulatory Network in Breast Cancer

Coronin 2A (CORO2A) is a novel component of the N-CoR (nuclear receptor co-repressor) complex. Abnormal CORO2A expression is associated with carcinogenesis. We used databases from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), and analyzed CORO2A expression and gene regulation networks in breast cancer. Expression was analyzed using GEO and TCGA database and further validated in breast cancer samples collected in our clinic. The prognostic value of CORO2A was explored by using the Kaplan–Meier survival analysis and Cox proportional hazards regression analysis. LinkedOmics was used to identify coexpressed genes associated with CORO2A. After analyzing the intersection of coexpressed genes correlated with CORO2A and differentially expressed genes after CORO2A silencing, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of the intersecting genes were conducted by using FunRich software. Transwell assays were performed in breast cancer cells to determine the effect of CORO2A on cell migration. MTS, colony formation, and cell cycle distribution assays were performed in breast cancer cells to determine the effect of CORO2A on cell proliferation. Gene enrichment analysis was employed to explore the target networks of transcription factors and miRNAs. We found that CORO2A was upregulated and that the elevated expression of CORO2A was associated with poor overall survival (OS) and relapse-free survival (RFS) in TNBC patients. Further bioinformatics analysis of public sequencing data and our own RNA-Seq data revealed that CORO2A was probably involved in the epithelial-to-mesenchymal transition process and might have a significant effect on the migration of breast cancer cells, which might be mediated via pathways involving several miRNAs and MYC transcription factors. Functionally, the knockdown of CORO2A inhibited cell migration, decreased viability, and colony formation and induced cell cycle arrest in the G0/G1 phase in breast cancer cells. These results demonstrate that bioinformatics-based analysis efficiently reveals information about CORO2A expression and its potential regulatory networks in breast cancer, laying a foundation for further mechanistic research on the role of CORO2A in carcinogenesis. Moreover, CORO2A promotes the migration and proliferation of breast cancer cells and may have an important function in breast cancer progression. CORO2A is a potential prognostic predictor for TNBC patients. Targeting CORO2A may provide promising therapy strategies for breast cancer treatment.

Efficacy of abiraterone combined with flutamide on prostate cancer patients and its effect on serum miR-493-5p and miR-195-5p

Efficacy of abiraterone combined with flutamide on patients with prostate cancer (PCa) and its effect on levels of miR-493-5p and miR-195-5p contained in serum were investigated. The medical records of 146 PCa patients admitted to Longhua Hospital Shanghai University of Traditional Chinese Medicine from January 2011 to December 2013 were selected. Eighty-four patients were treated with abiraterone combined with flutamide as a study group, 62 patients were treated with abiraterone alone as a control group. The curative effect, adverse reactions, quality of life and five-year overall survival (OS) of the two groups were compared. The serum prostate-specific antigen (PSA) level was measured by radioimmunoassay at 3 days (T1) before treatment, 1 month (T2), 2 months (T3), and 6 months (T4) after treatment, and the relative expression of miR-493-5p and miR-195-5p in serum were detected by qRT-PCR. The total effective rate of the study group was significantly higher than that of the control group (P<0.05). The total incidence of toxic and side effects in the study group was significantly lower than that in the control group (P<0.05). The improvement rate of quality of life in the study group was significantly higher than that in the control group (P<0.05). OS in the study group was significantly higher than that in the control group at 5 years (P<0.05). There was no significant difference in serum PSA level between the two groups at T1 (P>0.05); there was no significant difference in the relative expression of miR-493-5p and miR-195-5p between the two groups at T1 (P>0.05). In conclusion, abiraterone combined with flutamide has better curative effect and lower incidence of adverse reactions in patients with metastatic castration-resistant PCa (CRPC) than abiraterone alone, and can increase the expression levels of miR-493-5p and miR-195-5p in patient serum.

MicroRNA-493-5p-mediated repression of the MYCN oncogene inhibits hepatic cancer cell growth and invasion

Primary hepatic tumors mainly include hepatocellular carcinoma (HCC), which is one of the most frequent causes of cancer‐related deaths worldwide. Thus far, HCC prognosis has remained extremely poor given the lack of effective treatments. Numerous studies have described the roles played by microRNAs (miRNAs) in cancer progression and the potential of these small noncoding RNAs for diagnostic or therapeutic applications. The current consensus supports the idea that direct repression of a wide range of oncogenes by a single key miRNA could critically affect the malignant properties of cancer cells in a synergistic manner. In this study, we aimed to investigate the oncogenes controlled by miR‐493‐5p, a major tumor suppressor miRNA that inactivates miR‐483‐3p oncomir in hepatic cancer cells. Using global gene expression analysis, we highlighted a set of candidate genes potentially regulated by miR‐493‐5p. In particular, the canonical MYCN protooncogene (MYCN) appeared to be an attractive target of miR‐493‐5p given its significant inhibition through 3′‐UTR targeting in miR‐493‐5p‐rescued HCC cells. We showed that MYCN was overexpressed in liver cancer cell lines and clinical samples from HCC patients. Notably, MYCN expression levels were inversely correlated with miR‐493‐5p in tumor tissues. We confirmed that MYCN knockdown mimicked the anticancer effect of miR‐493‐5p by inhibiting HCC cell growth and invasion, whereas MYCN rescue hindered miR‐493‐5p activity. In summary, miR‐493‐5p is a pivotal miRNA that modulates various oncogenes after its reexpression in liver cancer cells, suggesting that tumor suppressor miRNAs with a large spectrum of action could provide valuable tools for miRNA replacement therapies.

Long noncoding RNA GAS6-AS2 sponges microRNA-493, thereby enhancing the malignant characteristics of breast cancer cells via upregulation of FUT4

Long noncoding RNA (lncRNA) GAS6-AS2 serves as an oncogenic lncRNA in various types of human cancer. In this study, we attempted to examine the functions of GAS6-AS2 in breast cancer (BC) and explore the potential mechanisms involved. Reverse-transcription quantitative PCR was carried out to determine GAS6-AS2 expression in BC tissues and cell lines. Multiple functional experiments, including a Cell Counting Kit-8 assay, Transwell migration and invasion assays, and an in vivo nude-mouse xenograft experiment, were conducted to evaluate the effects of GAS6-AS2 in BC cells. GAS6-AS2 expression was high in BC tumors, manifesting a strong correlation with tumor size, lymph node metastasis, TNM stage, and shorter overall survival in patients with BC. A knockdown of GAS6-AS2 restricted BC cell proliferation, migration, and invasion in vitro and retarded tumor growth in vivo. With regard to its mechanism, GAS6-AS2 acted as a competing endogenous RNA that sponged microRNA-493 (miR-493), thereby increasing the expression of fucosyltransferase IV (FUT4). Either miR-493 inhibition or FUT4 upregulation abrogated the consequences of GAS6-AS2 knockdown in BC cells. These results revealed that GAS6-AS2 sponges miR-493 to enhance the malignant characteristics of BC in vitro and in vivo by increasing FUT4 expression. Thus, this lncRNA is an effective therapeutic target in BC and a promising diagnostic biomarker of this cancer.

Long noncoding RNA AC114812.8 promotes the progression of bladder cancer through miR-371b-5p/FUT4 axis

Bladder cancer (BC) brings a heavy burden to afflicted patients worldwide. In order to find new diagnostic markers and therapeutic targets for this disease, we investigated the role of a novel lncRNA, AC114812.8, in bladder cancer progression. Clone formation and CCK-8 assays were used to detect the proliferative capacity of the cells, and the transwell assay was used to explore their invasion and migration abilities. Wound healing experiments were also used to detect cell migration. Luciferase reporter assays were used to investigate the interactions between lncRNA, target gene and miRNA. The expression of FUT4 and marker genes related to epithelial-mesenchymal transition was explored through western blot analysis. Our findings revealed that AC114812.8 was significantly upregulated in BC and could markedly facilitate the proliferation, migration, and invasion of bladder cancer cells both in vitro and in vivo. Furthermore, duel-luciferase reporter assay revealed that AC114812.8 could regulate the FUT4 expression level by sponging miR-371b-5p to facilitate BC progression. We detected the levels of EMT-related biomarkers in AC114812.8-overexpressing BC cells by western blot analysis and found that AC114812.8 could promote EMT process. Rescue experiments showed that miR-371b-5p could rescue the effect of AC114812.8 on proliferation and metastasis of BC. Our results suggest that AC114812.8 could be a novel prognostic biomarker and therapeutic target for bladder cancer.

Multifaceted Impact of MicroRNA 493-5p on Genome-Stabilizing Pathways Induces Platinum and PARP Inhibitor Resistance in BRCA2-Mutated Carcinomas

BRCA1/2-mutated ovarian cancers (OCs) are defective in homologous recombination repair (HRR) of double-strand breaks (DSBs) and thereby sensitive to platinum and PARP inhibitors (PARPis). Multiple PARPis have recently received US Food and Drug Administration (FDA) approval for treatment of OCs, and resistance to PARPis is a major clinical problem. Utilizing primary and recurrent BRCA1/2-mutated carcinomas from OC patients, patient-derived lines, and an in vivo BRCA2-mutated mouse model, we identified a microRNA, miR-493-5p, that induced platinum/PARPi resistance exclusively in BRCA2-mutated carcinomas. However, in contrast to the most prevalent resistance mechanisms in BRCA mutant carcinomas, miR-493-5p did not restore HRR. Expression of miR-493-5p in BRCA2-mutated/depleted cells reduced levels of nucleases and other factors involved in maintaining genomic stability. This resulted in relatively stable replication forks, diminished single-strand annealing of DSBs, and increased R-loop formation. We conclude that impact of miR-493-5p on multiple pathways pertinent to genome stability cumulatively causes PARPi/platinum resistance in BRCA2 mutant carcinomas.

The Diverse Contributions of Fucose Linkages in Cancer

Fucosylation is a post-translational modification of glycans, proteins, and lipids that is responsible for many biological processes. Fucose conjugation via α(1,2), α(1,3), α(1,4), α(1,6), and O'- linkages to glycans, and variations in fucosylation linkages, has important implications for cancer biology. This review focuses on the roles that fucosylation plays in cancer, specifically through modulation of cell surface proteins and signaling pathways. How L-fucose and serum fucosylation patterns might be used for future clinical diagnostic, prognostic, and therapeutic approaches will be discussed.

Stereoselective Anti-Cancer Activities of Ginsenoside Rg3 on Triple Negative Breast Cancer Cell Models

Ginsenoside Rg3 (Rg3) has two epimers, 20(S)-ginsenoside Rg3 (SRg3) and 20(R)-ginsenoside Rg3 (RRg3), and while Rg3 itself has been reported to have anti-cancer properties, few studies have been reported on the anti-cancer effects of the different epimers. The aim was to investigate the stereoselective effects of the Rg3 epimers on triple negative breast cancer (TNBC) cell lines, tested using cell-based assays for proliferation, apoptosis, cell cycle arrest, migration and invasion. Molecular docking showed that Rg3 interacted with the aquaporin 1 (AQP1) water channel (binding score -9.4 kJ mol-1). The Xenopus laevis oocyte expression system was used to study the effect of Rg3 epimers on the AQP1 water permeability. The AQP1 expression in TNBC cell lines was compared with quantitative-polymerase chain reaction (PCR). The results showed that only SRg3 inhibited the AQP1 water flux and inhibited the proliferation of MDA-MB-231 (100 μM), due to cell cycle arrest at G0/G1. SRg3 inhibited the chemoattractant-induced migration of MDA-MB-231. The AQP1 expression in MDA-MB-231 was higher than in HCC1143 or DU4475 cell lines. These results suggest a role for AQP1 in the proliferation and chemoattractant-induced migration of this cell line. Compared to SRg3, RRg3 had more potency and efficacy, inhibiting the migration and invasion of MDA-MB-231. Rg3 has stereoselective anti-cancer effects in the AQP1 high-expressing cell line MDA-MB-231.

MEG3-derived miR-493-5p overcomes the oncogenic feature of IGF2-miR-483 loss of imprinting in hepatic cancer cells

Numerous studies have described the critical role played by microRNAs (miRNAs) in cancer progression and the potential of these small non-coding RNAs for diagnostic or therapeutic applications. However, the mechanisms responsible for the altered expression of miRNAs in malignant cells remain poorly understood. Herein, via epigenetic unmasking, we identified a group of miRNAs located in the imprinted delta like non-canonical Notch ligand 1 (DLK1)-maternally expressed 3 (MEG3) locus that were repressed in hepatic tumor cells. Notably, miR-493-5p epigenetic silencing was correlated with hypermethylation of the MEG3 differentially regulated region (DMR) in liver cancer cell lines and tumor tissues from patients. Experimental rescue of miR-493-5p promoted an anti-cancer response by hindering hepatocellular carcinoma (HCC) cell growth in vitro and tumor progression in vivo. We found that miR-493-5p mediated part of its tumor-suppressor activity by abrogating overexpression of insulin-like growth factor 2 (IGF2) and the IGF2-derived intronic oncomir miR-483-3p in HCC cells characterized by IGF2 loss of imprinting (LOI). In summary, this study describes an unknown miRNA-dependent regulatory mechanism between two distinct imprinted loci and a possible therapeutic window for liver cancer patients exhibiting IGF2-miR-483 LOI and amplification.

MicroRNA-493-5p inhibits proliferation and metastasis of osteosarcoma cells by targeting Kruppel-like factor 5

Osteosarcoma, including spinal osteosarcoma, has properties of high degree of malignancy, high rate of recurrence, and high incidence of metastasis. microRNAs can exert oncogenic or tumor suppressive roles in cancer cells. This study explored the effects of microRNA-493-5p (miR-493-5p) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as the underlying possible mechanism. First, the expression of miR-493-5p in osteosarcoma tissues and cells was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Then, the effects of miR-493-5p overexpression (or suppression) on osteosarcoma cell viability, migration, invasion, and apoptosis, as well as Kruppel-like factor 5 (KLF5) expression, were assessed using the Cell Counting Kit-8 assay, two-chamber transwell assay, Annexin V-FITC/PI apoptosis detection kit, qRT-PCR, and western blotting, respectively. Finally, the roles of KLF5 in miR-493-5p suppression-induced U20S cell viability, migration, and invasion enhancement, as well as the PI3K/AKT pathway activation, were evaluated. We found that miR-493-5p had lower expression in tumor tissues of spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited osteosarcoma U20S cell viability, migration, and invasion, but induced cell apoptosis. On the contrary, suppression of miR-493-5p-promoted U20S cell viability, migration, and invasion. KLF5 was a direct target gene of miR-493-5p, which participated in the effects of miR-493-5p on U20S cell viability, migration, invasion, and apoptosis. Furthermore, suppression of the miR-493-5p activated PI3K/AKT pathway in U20S cells by upregulating KLF5. In conclusion, we revealed that miR-493-5p exerted tumor suppressive roles in spinal osteosarcoma and osteosarcoma cells. Overexpression of miR-493-5p inhibited proliferation and metastasis of osteosarcoma cells by downregulating KLF5 and inactivating the PI3K/AKT signaling pathway.

Circulating microRNAs associated with prolonged overall survival in lung cancer patients treated with nivolumab

BACKGROUND

The introduction of immune check-point inhibition in non-small cell lung cancer (NSCLC) therapy represents improved prospects for the patients. The response rates to check-point inhibitors are approximately 20% in unselected NSCLC patients. Increasing levels of tumor PD-L1 expression are associated with higher response rates. However, patients with low PD-L1 levels may also have durable responses, and improved strategies for patient stratification are needed.

MATERIAL AND METHODS

In this study, we investigated circulating microRNAs aiming to identify circulating predictive biomarkers associated with increased overall survival after immune check-point treatment. Using next generation sequencing, we performed microRNA profiling in serum from NSCLC patients (n = 20) treated with nivolumab. Serum samples from 31 patients were used for validation using qPCR assays. Serum samples were collected prior to immune therapy initiation.

RESULTS

Based on multivariate regression analysis, we identified a signature of seven microRNAs (miR-215-5p, miR-411-3p, miR-493-5p, miR-494-3p, miR-495-3p, miR-548j-5p and miR-93-3p) significantly associated with overall survival (OS) > 6 months in discovery cohort (p = .0003). We further validated this in another similar set of samples (n = 31) and the model was significantly associated with overall survival (OS) > 6 months (p = .001) with sensitivity and specificity of 71% and 90%, respectively.

CONCLUSIONS

In this study of circulating microRNAs, we have identified a 7-miR signature associated with survival in nivolumab-treated NSCLC patients. This signature may lead to better treatment options for patients with NSCLC, but a validation in an independent cohort is needed to confirm the predicted potential.

Upregulation of lncRNA ADAMTS9-AS2 Promotes Salivary Adenoid Cystic Carcinoma Metastasis via PI3K/Akt and MEK/Erk Signaling

Neurotropic infiltrative growth and distant metastasis are the main causes of death in salivary adenoid cystic carcinoma (SACC) patients. Long noncoding RNAs (lncRNAs) are involved in many human neoplasms, however, their potential roles in SACC are unclear. In our study, we found that ADAM metallopeptidase with thrombospondin type 1 motif, 9 (ADAMTS9) antisense RNA 2 (ADAMTS9-AS2) was significantly upregulated in SACC patients with metastasis and SACC-lung metastasis (LM) cells. Moreover, ADAMTS9-AS2 expression was closely associated with the prognosis and distant metastasis in SACC patients. Next, we found that c-myc could specifically bind to the promoter of ADAMTS9-AS2 and activated its transcription. Knockdown of ADAMTS9-AS2 significantly inhibited migration and invasion of SACC cells in vitro and distant lung metastasis in vivo. Furthermore, ADAMTS9-AS2, which mainly expressed in the cytoplasm, shared microRNA (miRNA) response elements with Integrin α6 (ITGA6). Overexpression of ADAMTS9-AS2 competitively bound to miR-143-3p that inhibited ITGA6 from miRNA-mediated degradation, and thus it activated the activity of PI3K/Akt and MEK/Erk signaling and facilitated SACC metastasis. In summary, ADAMTS9-AS2 promotes migration and invasion in SACC by competing with miR-143-3p. This sheds a new insight into the regulation mechanism of ADAMTS9-AS2, and it provides a possible application for the SACC treatment.

MicroRNA-493 is a prognostic factor in triple-negative breast cancer

Breast cancer is one of the most common malignant diseases in women. Triple‐negative breast cancer (TNBC) shows higher aggressiveness and recurrence rates than other subtypes, and there are no effective targets or tailored treatments for TNBC patients. Thus, finding effective prognostic markers for TNBC could help clinicians in their ability to care for their patients. We used tissue microarrays (TMAs) to detect microRNA‐493 (miR‐493) expression in breast cancer samples. A miRCURY LNA detection probe specific for miR‐493 was used in in situ hybridization assays. Staining results were reviewed by two independent pathologists and classified as high or low expression of miR‐493. Kaplan–Meier survival plots and multivariate Cox analysis were carried out to clarify the relationship between miR‐493 and survival. In the Kaplan–Meier analysis, patients with high miR‐493 expression had better disease‐free survival than patients with low miR‐493 expression. After adjusting for common clinicopathological factors in breast cancer, the expression level of miR‐493 was still a significant prognostic factor in breast cancer. Further subtype analysis revealed that miR‐493 expression levels were only significantly prognostic in TNBC patients. These results were validated in the Molecular Taxonomy of Breast Cancer International Consortium database for overall survival. We proved the prognostic role of miR‐493 in TNBC by using one of the largest breast cancer TMAs available and validated it in a large public RNA sequencing database.

High expression of miR-493-5p positively correlates with clinical prognosis of non small cell lung cancer by targeting oncogene ITGB1

Increasing evidence supports that microRNA (miRNA)-mediated gene regulation plays a significant functional role in cancer progression. To investigate the expression and clinical significance of ITGB1 in non small cell lung cancer (NSCLC), the expression levels of ITGB1 in NSCLC tissues and human normal lung tissues were analyzed in silico using genes microarray, KEGG pathway and hierarchical clustering analysis followed by validation with quantitative RT-PCR. Our results showed that ITGB1 was upregulated in NSCLC tissues when compared with normal lung tissues. Survival analysis based on the qRT-PCR data established that ITGB1 expression was attentively related to the prognosis of NSCLC, and patients with higher ITGB1 expression had shorter overall survival (OS). Moreover, ITGB1 was confirmed to be a direct target of miR-493-5p. Furthermore, concomitant high expression of ITGB1 and low expression of miR-493-5p correlated with a shorter median OS and PFS in NSCLC patients. In conclusion, our results provide the first evidence that ITGB1 is a direct target of miR-493-5p suggesting that ITGB1 and miR-493-5p may have potential prognostic value and may be useful as tumor biomarkers for the diagnosis of NSCLC patients.

Microarray profile of circular RNAs identifies hsa_circ_0014130 as a new circular RNA biomarker in non-small cell lung cancer

Accumulating evidence has revealed that aberrant Circular RNAs (circRNAs) expression plays important roles in carcinogenesis and tumor progression. However, their role in non-small cell lung cancer (NSCLC) remains unclear. In this study, we first used circRNA microarrays to screen for tumour-specific circRNA candidates in between NSCLC (n = 3) and adjacent lung (n = 3) tissue. Among the circRNA expression profile, two circRNAs (hsa_circ_0014130 and hsa_circ_0016760) were selected for validation in ten pairs of NSCLC and adjacent non-cancerous tissues by real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Only hsa_circ_0014130 exhibited significantly overexpressed in NSCLC tissues (P < 0.001), which were further confirmed in another 36 matched tissue samples using qRT-PCR. Hsa_circ_0014130 expression significantly correlated with TNM stage (P = 0.001) and lymphatic metastasis (P = 0.004). The area under the receiver operating characteristic curve was 0.878 (95% confidence interval = 0.804–0.951; P < 0.001), which showed good diagnostic potential. Bioinformatics platforms predicted that hsa_circ_0014130 might interact with five miRNAs and their corresponding mRNAs. Gene oncology analysis and pathway analysis revealed that hsa_circ_0014130 could participate in NSCLC development. In summary, our findings indicated that hsa_circ_0014130 could be used as a potential NSCLC biomarker and might be closely related to the carcinogenesis of NSCLC.

Epigenetic silencing of miR-493 increases the resistance to cisplatin in lung cancer by targeting tongue cancer resistance-related protein 1(TCRP1)

Background

The potential mechanisms regarding how methylation of microRNA(miRNA) CpG Island could regulate cancer cell chemo-resistance remains unclear. This study aims to explore the epigenetic dysregulation mechanism of miRNA-493 and the ability to modulate lung cancer cell chemotherapy resistance.

Methods

Real-time quantitative PCR (qRT-PCR) and In situ hybridization (ISH) were used to analyze the expression of miR-493 in lung cancer cell lines and tumor tissue, respectively. Bisulfite sequencing PCR (BSP) was used to exam the promoter CpG Island of miR-493. The effect of miR-493 on chemosensitivity was evaluated by cell viability assays, apoptosis assays and in vivo experiment. The DNA damage was measured by γ-H2AX immunofluorescence. Luciferase reporter assay was used to assess the target genes of miR-493. Expression of target proteins and downstream molecules were analyzed by Western blot.

Results

miR-493 is silenced in resistant lung cancer cell due to the aberrant DNA methylation. Enforced expression of miR-493 in lung cancer cells promotes chemotherapy sensitivity to cisplatin through impairing the DNA damage repair and increasing the cells apoptosis in vitro and in vivo. Furthermore, we identify that TCRP1 is a direct functional target of miR-493. Ectopic expression of TCRP1 attenuated increased apoptosis in miR-493-overexpressing lung cancer cells upon cisplatin treatment. Meanwhile, miR-493 level is negatively correlated with TCRP1 expression in lung cancer patients and TCRP1 expression were correlated with poor survival.

Conclusions

Our results highlight that hyper-methylation of miR-493CpG island might play important roles in the development of lung cancer chemo-resistance by targeting TCRP1, which might be used as a potential therapeutic target in preventing the chemo-resistance of lung cancer.

MicroRNA-374c-5p regulates the invasion and migration of cervical cancer by acting on the Foxc1/snail pathway

Some microRNAs (miRNAs) have been implicated in cervical cancer development and progression. However, the roles and mechanisms of several miRNAs in epithelial-mesenchymal transition (EMT) in cervical cancer remain poorly understood. Here, we conducted a microarray analysis and found that miR-374c-5p was most down-regulated miRNA in TGFβ1-treated cervical cancer cells compared to the expression in parental cell lines. Ectopic overexpression of miR-374c-5p inhibited cervical cancerl invasion and migration in TGFβ1- treated cervical cancer cells. Conversely, miR-374c-5p knockdown increased the migration and invasion abilities of parental cell lines. Moreover, miR-374c-5p exerted its function by directly targeting the FOXC1 3^/-UTR and repressing FOXC1 expression, thus leading to suppression of snail. In clinical cervical cancer samples, lower miR-374c-5p expression predicted poor patient survival and highe lymph node metastasis in cervical cancers. miR-374c-5p was negatively correlated with FOXC1, which was upregulated in cervical cancers with lymph node metastasis. Taken together, our findings highlight the important role of miR-374c-5p in regulating cervical cancers metastasis by targeting FOXC1, suggesting that miR-374c-5p may represent a novel potential therapeutic target and prognostic marker in cervical cancers.

Tumor-suppressive miR-26a and miR-26b inhibit cell aggressiveness by regulating FUT4 in colorectal cancer

Metastasis is a multistep molecular network process, which is the major cause of death in patients with colorectal cancer (CRC). MicroRNAs (miRNAs) play pivotal roles in tumorigenesis as either tumor suppressors or oncogenes. Increased expression of fucosyltransferase4 (FUT4) has been reported to be associated with the invasive and metastatic properties of CRC. Here to identify potential key miRNAs and their target genes for colorectal cancer (CRC), we compared miRNA expression profiles between metastatic CRC cell SW620 and primary CRC cell SW480. Microarray analysis revealed that there were 85 differentially expressed miRNAs in SW620 cells with highly metastatic potential compared to SW480 cells with lowly metastatic potential. The expression of miR-26a and miR-26b were lower in SW620 cells than in SW480 cells, as well as downregulated in tumor tissues than in adjacent normal tissues of CRC patients. By applying bioinformatic approaches for the prediction of miRNA targeting 3'-UTR of FUT4, we identified FUT4 as one of the miR-26a/26b-targeted genes, while the expression of the target gene exhibited patterns opposite to that of miR-26a/26b in CRC cell lines, tumor tissues and corresponding adjacent tissues. Forced miR-26a/26b expression affected migratory behavior of CRC cells and FUT4 expression, while altered expression of FUT4 in CRC cell lines modulated progression upon transfection with miR-26a/26b mimic or inhibiter. FUT4 also regulated directly aggressiveness of SW620 and SW480 cells. Moreover, statistical analyses revealed that low miR-26a/26b levels and high expression of FUT4 were positively correlated with poor overall survival. The identified CRC-restricted miR-26a and miR-26b might be implicated in cancer progression via their target gene FUT4, suggesting their potential usage in CRC treatment.

Downregulation of miR-493 promoted melanoma proliferation by suppressing IRS4 expression

Accumulating evidence indicated that aberrantly expressed microRNAs play critical roles in the initiation and progression of human cancers. However, the underlying functions of miR-493 in human melanoma remains unknown. Here, our study found that miR-493 expression was downregulated in human melanoma tissues and cells. Overexpression of miR-493 suppressed cell proliferation and cell cycle in human melanoma cell line A375. IRS4 was defined as a target for downregulation by miR-493 and was confirmed by luciferase assay. We also found that knockdown of IRS4 counteracted the proliferation promotion by miR-493 inhibitor. In summary, these results demonstrated that miR-493 acts as a tumor suppressor and inhibits cell proliferation and cell cycle in human melanoma by directly targeting IRS4.

Epigenetic Bases of Aberrant Glycosylation in Cancer

In this review, the sugar portions of glycoproteins, glycolipids, and glycosaminoglycans constitute the glycome, and the genes involved in their biosynthesis, degradation, transport and recognition are referred to as “glycogenes“. The extreme complexity of the glycome requires the regulatory layer to be provided by the epigenetic mechanisms. Almost all types of cancers present glycosylation aberrations, giving rise to phenotypic changes and to the expression of tumor markers. In this review, we discuss how cancer-associated alterations of promoter methylation, histone methylation/acetylation, and miRNAs determine glycomic changes associated with the malignant phenotype. Usually, increased promoter methylation and miRNA expression induce glycogene silencing. However, treatment with demethylating agents sometimes results in silencing, rather than in a reactivation of glycogenes, suggesting the involvement of distant methylation-dependent regulatory elements. From a therapeutic perspective aimed at the normalization of the malignant glycome, it appears that miRNA targeting of cancer-deranged glycogenes can be a more specific and promising approach than the use of drugs, which broad target methylation/acetylation. A very specific type of glycosylation, the addition of GlcNAc to serine or threonine (O-GlcNAc), is not only regulated by epigenetic mechanisms, but is an epigenetic modifier of histones and transcription factors. Thus, glycosylation is both under the control of epigenetic mechanisms and is an integral part of the epigenetic code.

miR-493-5p suppresses hepatocellular carcinoma cell proliferation through targeting GP73

Aberrant expression of miRNAs has been documented to play critical roles in the development and progression of hepatocellular carcinoma (HCC). However, the expression pattern, functional roles and regulatory mechanism of miR-493-5p in HCC have not been addressed. Herein, we found that miR-493-5p was significantly downregulated in HCC tissues and was tightly associated with tumor size, tumor differentiation grade and TNM stage of HCC patients. Overexpression of miR-493-5p inhibited HCC cell proliferation, arrested cell cycle in G0/G1 phase and induced cell apoptosis. Bioinformatical analysis and luciferase reporter assay further proved that Golgiprotein73 (GP73), an oncogene which was generally overexpressed in HCC, acted as a novel target of miR-493-5p. MiR-493-5p could inhibit GP73 both mRNA and protein expression. Moreover, overexpression of GP73 could reverse the inhibitory effects of miR-493-5p mediated HCC cell proliferation. In addition, upregulated GP73 in HCC tissues was inversely correlated with the miR-493-5p expression levels in the HCC tissues. Collectively, our present study demonstrates that miR-493-5p is downregulated in HCC and it can suppress the proliferation of HCC cells, partly at least, via directly targeting GP73. Besides, this study provides a novel insight into the mechanism of hepatocarcinogenesis and a promising blueprint for miR-493-5p-GP73 axis-oriented treatment of HCC.

miR-145 inhibits proliferation and migration of breast cancer cells by directly or indirectly regulating TGF-β1 expression

Studies have demonstrated low expression of miR-145 associated with cell proliferation and migration in a wide variety of tumors. Here, we studied the expression of miR-145 in relation to the occurrence and development of breast cancer. Total RNA from breast cancer tissue and corresponding adjacent normal tissue was extracted and used to detect miR-145 expression by quantitative real-time polymerase chain reaction (qRT-PCR). We also transfected breast cancer cells with hsa-miR-145 mimics, hsa-miR-145 inhibitor, mimics negative control (mimics NC) or inhibitor negative control (inhibitor NC). Cell proliferation was analyzed by colony formation assays and methyl thiazolyl tetrazolium assays. Cell proliferation in breast cancer cells was decreased after overexpression of miR-145 and increased following miR-145 suppression. Cell migration and invasion were assessed using Transwell and wound healing assays, respectively, and were also decreased after overexpression of miR-145 and increased after miR-145 suppression in breast cancer cells. Finally, western blot assays showed that overexpression of miR-145 inhibited expression of transforming growth factor-β1 (TGF-β1). Collectively, these data suggest that miR-145 may inhibit TGF-β1 protein expression which may in turn contribute to tumor formation.