MicroRNA-130b promotes tumor development and is associated with poor prognosis in colorectal cancer.
ABSTRACT: MicroRNA-130b (miR-130b) is involved in several biologic processes; its role in colorectal tumorigenesis has not been addressed so far. Herein, we demonstrate that miR-130b up-regulation exhibits clinical relevance as it is linked to advanced colorectal cancers (CRCs), poor patients' prognosis, and molecular features of enhanced epithelial-mesenchymal transition (EMT) and angiogenesis. miR-130b high-expressing cells develop large, dedifferentiated, and vascularized tumors in mouse xenografts, features that are reverted by intratumor injection of a specific antisense RNA. In contrast, injection of the corresponding mimic in mouse xenografts from miR-130b low-expressing cells increases tumor growth and angiogenic potential while reduces the epithelial hallmarks. These biologic effects are reproduced in human CRC cell lines. We identify peroxisome proliferator-activated receptor ? (PPAR?) as an miR-130b direct target in CRC in vitro and in vivo. Notably, the effects of PPAR? gain- and loss-of-function phenocopy those due to miR-130b down-regulation or up-regulation, respectively, underscoring their biologic relevance. Furthermore, we provide mechanistic evidences that most of the miR-130b-dependent effects are due to PPAR? suppression that in turn deregulates PTEN, E-cadherin, Snail, and vascular endothelial growth factor, key mediators of cell proliferation, EMT, and angiogenesis. Since higher levels of miR-130b are found in advanced tumor stages (III-IV), we propose a novel role of the miR-130b-PPAR? axis in fostering the progression toward more invasive CRCs. Detection of onco-miR-130b and its association with PPAR? may be useful as a prognostic biomarker. Its targeting in vivo should be evaluated as a novel effective therapeutic tool against CRC.
Project description:MicroRNA 130b (miR-130b) is significantly dysregulated in various human tumor types. In this study, using a microarray assay, we characterized the upregulation of miR-130b expression in colorectal cancer (CRC) specimens. However, there is limited knowledge about the roles of aberrant miR-130b expression in CRC. Our studies in CRC cells demonstrated that miR-130b significantly decreases cell migration and invasion, but it has no evidently effects on cell proliferation and apoptosis. In the overexpression miR-130b CRC cells and the CRC specimens, we observed a decreased level of integrin ?1 protein, which is considered as a key molecule involved in cell motility. The targeting of the 3'-UTR region of integrin ?1 gene by miR-130b was revealed using a luciferase reporter assay. The regulation of integrin ?1 by miR-130b was further shown using the miR-130b mimics and the inhibitor of miR-130b. The impaired motility of the miR-130b overexpression cells is recovered partly by the expression of integrin ?1 lacking the 3'-UTR. Additionally, the knockdown of integrin ?1 also gives rise to a decrease in cell migration and invasion, which is similar to the impeded motility due to overexpression of miR-130b in CRC cells. Furthermore, the inverse expressions of miR-130b and integrin ?1 were observed in CRC specimens. In summary, these data demonstrate that miR-130b downregulates its target-integrin ?1, leading to the impaired migration and invasion of CRC cells.
Project description:In this study, two experiments were conducted to determine the role of miR-130b in dexamethasone (DEX)-induced lipid accumulation. Porcine preadipocytes were treated with 10-6 M DEX for 48 h to investigate effects of DEX in lipid accumulation. Next, in order to illustrate the regulatory role of miR-130b on lipid accumulation induced by DEX, miRNA scrambled control (miR-SC), miR-130b overexpression plasmid and miR-130b inhibitor were respectively transfected into porcine preadipocytes at 24 h before DEX treatment for 48 h (miR-SC-DEX, miR-130b-DEX and miR-130b-inhibitor-DEX). Results showed that 10-6 M DEX significantly increased TG concentration and expression of miR-130b as well as its target gene peroxisome proliferator-activated receptor-? (PPAR-?). Dual-luciferase reporter assays indicated that PPAR-? expression was negatively regulated by miR-130b, while this effect was abolished with cotransfection of miR-130b and miR-130b inhibitor. In addition, miR-130b-DEX did not change cell proliferation but significantly decreased TG concentration and PPAR-? expression compared to miR-SC-DEX cells, while miR-130b-inhibitor-DEX cells presented opposite results. Furthermore, miR-130b-DEX significantly reduced expression of PPAR-? downstream factor perilipin 1 as well as adipogenesis genes fatty acid synthase, acetyl coenzyme A carboxylase, 11? hydroxysteroid dehydrogenase type 1 and fat mass and obesity-associated gene, whereas expression as well as enzyme activity of adipose triglyceride lipase and hormone-sensitive lipase were greatly increased. Overall, these results clarified the role of miR-130b in DEX-induced increase of lipid accumulation in porcine preadipocytes, suggesting that miR-130b might be deemed as a novel potential therapeutic target for DEX-induced increase of lipid accumulation, and consequently provide new insights in obesity control.
Project description:Cell invasion is crucial for high mortality and recurrence rate in glioma. Epithelial-mesenchymal transition (EMT) is an important step in cancer invasion. Metadherin (MTDH) contributes to EMT in several cancers, but the role and mechanism of MTDH in EMT-like process of glioma remain unknown. Here we demonstrate that MTDH was overexpressed in glioma tissues and cells and induced EMT-like change and invasion of glioma cells. Interestingly, MTDH could modulate the expression of a group of glioma-related miRNAs. In particular, MTDH upregulated miR-130b transcription via acting as a coactivator of NF-kB. MiR-130b promoted EMT-like change and invasion of glioma cells through targeting multiple EMT-related genes, including PTEN, PPP2CA and SMAD7. In addition, PTEN acted as the competing endogenous RNA (ceRNA) to affect PPP2CA and SMAD7 expression, and inhibited EMT-like change in glioma cells. Furthermore, miR-130b mediated EMT-like change induced by MTDH, and MTDH inhibited the expression levels of PTEN, PPP2CA and SMAD7. Taken together, we reveal a novel mechanism that MTDH induces EMT-like change and invasion of glioma via the regulation of miR-130b-ceRNAs, providing the first direct link between MTDH and miRNAs in cancer cells.
Project description:The tumor suppressor gene p53 has been implicated in the regulation of epithelial-mesenchymal transition (EMT) and tumor metastasis by regulating microRNA (miRNA) expression. Here, we report that mutant p53 exerts oncogenic functions and promotes EMT in endometrial cancer (EC) by directly binding to the promoter of miR-130b (a negative regulator of ZEB1) and inhibiting its transcription. We transduced p53 mutants into p53-null EC cells, profiled the miRNA expression by miRNA microarray and identified miR-130b as a potential target of mutant p53. Ectopic expression of p53 mutants repressed the expression of miR-130b and triggered ZEB1-dependent EMT and cancer cell invasion. Loss of an endogenous p53 mutation increased the expression of miR-130b, which resulted in reduced ZEB1 expression and attenuation of the EMT phenotype. Furthermore, re-expression of miR-130b suppressed mutant p53-induced EMT and ZEB1 expression. Importantly, the expression of miR-130 was significantly reduced in EC tissues, and patients with higher expression levels of miR-130b survived longer. These data provide a novel understanding of the roles of p53 gain-of-function mutations in accelerating tumor progression and metastasis through modulation of the miR-130b-ZEB1 axis.
Project description:MicroRNA-130b (miR-130b) downregulation has been identified in diabetes, but the role and mechanisms for miR-130b in mediating renal tubulointerstitial fibrosis in diabetic nephropathy (DN) remain unknown. We demonstrated that plasma miR-130b downregulation exhibited clinical and biological relevance as it was linked to increased serum creatinine, ?2-microglobulin and proteinuria, increased Snail expression and tubulointerstitial fibrosis in renal biopsies of DN patients. MiR-130b inhibitor caused Snail upregulation and enhanced molecular features of epithelial-to-mesenchymal transition (EMT) in high glucose (30?mM) cultured NRK-52E cells. In contrast, miR-130b mimic downregulated Snail expression and increased epithelial hallmarks. Notably, Snail was identified as an miR-130b direct target and inversely correlated with E-CADHERIN expression. Furthermore, the miR-130b-dependent effects were due to Snail suppression that in turn deregulated E-CADHERIN, VIMENTIN, COLLAGEN IV and ?-smooth muscle actin (?-SMA), key mediators of EMT. These effects were reproduced in streptozotocin-induced diabetic rats. Thus, we propose a novel role of the miR-130b-SNAIL axis in fostering EMT and progression toward increased tubulointerstitial fibrosis in DN. Detection of plasma miR-130b and its association with SNAIL can be extrapolated to quantifying the severity of renal tubulointerstitial fibrosis. Targeting miR-130b could be evaluated as a potential therapeutic approach for DN.
Project description:We have shown previously that microvesicle (MV)-delivered miR-130b (miR-130b-MV) is able to target PPAR-? and subsequently reduce the lipid accumulation in vitro. However, the in vivo effect of miR-130b on fat deposition and glucose homeostasis remains unknown.Three-week-old C57BL/6 mice were fed a high-fat diet for 8 weeks and then intravenously injected with MV-packaged scrambled control microRNA (miRNA) or miR-130b every other day for 10 days. Glucose tolerance test was performed and body weight, epididymal fat weight, as well as the expression of lipid metabolic genes were determined. We showed that mice fed on high-fat diet for 8 weeks demonstrated significantly higher body weight, elevated blood glucose and impaired glucose tolerance. miR-130b-MV injection significantly reduced body weight and epididymal fat weight and partly restored glucose tolerance. miR-130b expression was significantly increased in the epididymal fat after miR-130b-MV injection while the protein content of its target gene PPAR-? was significantly suppressed, together with a significant up-regulation of the lipolysis genes, hormone sensitive lipase, monoglyceride lipase and leptin. Moreover, miR-130b-MV injection increased the expression of miR-378a and miR-378-3p that are reported to participate in the regulation of fat deposition.Our results indicate that miR-130b-MV is able to reduce the epididymal fat deposition and partly restore glucose tolerance, through translational repression of PPAR-? in a high-fat diet-induced obese mouse model.
Project description:BACKGROUND:Esophageal carcinoma is one of the most common malignancies with high cancer-related morbidity and mortality worldwide. MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate a wide variety of cellular processes, and also play an important role in the development and progression of cancers. In a previous microarray study, we demonstrated that miR-130b was upregulated in esophageal squamous cell carcinoma (ESCC) tissues. However, the biologic functions and the molecular mechanism of miR-130b in ESCC remain to be elucidated. METHODS:qRT-PCR assays were used to quantify miR-130b expression levels in ESCC samples. Novel targets of miR-130b were identified via a bioinformatics search and confirmed using a dual-luciferase reporter system. Western blotting and qRT-PCR assays were used to quantify the expression of the target gene PTEN (phosphatase and tensin homolog) and the downstream effector, Akt. ESCC cells over- or underexpressing miR-130b were analyzed for in vitro biologic functions. RESULTS:High levels of miR-130b were identified in 20 ESCC samples following comparison with adjacent non-neoplastic tissues. We confirmed that miR-130b interacted with the 3'-untranslated region of PTEN, and that an increase in the expression level of miR-130b negatively affected the protein level of PTEN. However, the dysregulation of miR-130b had no obvious impact on PTEN mRNA. As Akt is a downstream effector of PTEN, we explored if miR-130b affected Akt expression, and found that miR-130b indirectly regulated the level of phosphorylated Akt, while total Akt protein remained unchanged. Overexpression of miR-130b increased the proliferation of ESCC cells and enhanced their ability to migrate and invade. In contrast, the proliferation, migration, and invasion of ESCC cells were weakened when miR-130b expression was suppressed, which was reversed by PTEN-targeted siRNA. CONCLUSION:The results indicate that miR-130b plays an oncogenic role in ESCC cells by repressing PTEN expression and Akt phosphorylation, which would be helpful in developing miRNA-based treatments for ESCC.
Project description:Angiogenesis, one of the hallmarks of cancer, is essential for both tumor growth and metastasis. However, its molecular mechanisms in hepatocellular carcinoma (HCC) are largely unknown. Here, we report the role of HOXA5 in tumor angiogenesis of HCC. Methods: The expression of miR-130b-3p and HOXA5 was determined by qRT-PCR and immunohistochemistry, respectively. Capillary tube formation assay, chicken chorioallantoic membrane assay, and subcutaneous xenograft experiments were performed to investigate the role of miR-130-3p and HOXA5. Luciferase reporter assay and chromatin immunoprecipitation assay were performed to evaluate the interaction between Sp1, miR-130b-3p and HOXA5. Results: miR-130b-3p was found up-regulated in HCC and correlated with a poor prognosis. miR-130b-3p promoted HCC angiogenesis both in vitro and in vivo. Mechanistically, HOXA5 was validated as a direct target of miR-130b-3p. Furthermore, we demonstrated that HOXA5 was down-regulated in HCC and its down-regulation was associated with larger tumor size, shorter overall survival, and higher recurrence probability. Moreover, HOXA5 was significantly associated with angiogenesis biomarkers such as CD31 and CD34. Functional studies revealed that the knockdown of HOXA5 also significantly promoted HCC angiogenesis both in vitro and in vivo. Knocking-down HOXA5 significantly provoked HCC cells to induce the capillary tube formation, migration and proliferation of endothelial cells. In xenograft animal models, we found that a decrease of HOXA5 effectively enhanced tumor growth and increased microvessel densities. We further demonstrated that miR-130b-3p could be directly transcriptionally regulated by Sp1. Conclusions: This study showed that a dysregulation in the Sp1/miR-130b-3p/HOXA5 axis contributed to HCC progression and angiogenesis, and that HOXA5 can be considered as a promising therapeutic target for treating HCC.
Project description:Systemic lupus erythematosus (SLE) is a common but severe autoimmune systemic inflammatory disease. Lupus nephritis (LN) is a serious complication of SLE,affecting up to 70% of SLE patients. Circulating microRNAs (miRNA) are emerging as biomarkers for pathological conditions and play significant roles in intercellular communication. In present research, serum samples from healthy control, early and late stage LN patients were used to analyze the expression profile of miRNAs by microarray. Subsequent study demonstrated that miR-130b-3p in serum of patients with early stage LN were significantly up-regulated when compared with healthy controls. In addition,we have also observed that the expression of a large amount of circulating microRNAs significantly decreased in patients with late stage LN. The further analysis found that the expression of serum miR-130b-3p was positively correlated with 24-hour proteinuria and renal chronicity index in patients with early stage LN.Transfection of renal tubular cellline(HK-2)with miR-130b-3p mimics can promote epithelial-mesenchymal transition (EMT). The opposite effects were observed when transfected with miR-130b-3p inhibitors. MiR-130b-3p negatively regulated ERBB2IP expression by directly targeting the 3'-UTR of ERBB2IP The circulating miR-130b-3p might serve as a biomarker and play an important role in renal damage in early stage LN patients.
Project description:Nonalcoholic fatty liver disease (NAFLD) is due to the excessive lipid accumulation within hepatocytes. Metabolic nuclear receptors (MNRs) play great roles in lipid homeostasis. We have identified a novel long noncoding RNA (lncRNA), lnc-HC, which regulates hepatocytic cholesterol metabolism through reducing Cyp7a1 and Abca1 expression. Here, we further elucidate its roles in hepatic fatty acid and triglyceride (TG) metabolism through a novel lncRNA regulatory mechanism. The most prominent target of lnc-HC identified by in vitro study is PPAR?. Further studies revealed that lnc-HC negatively regulates PPAR? at both the mRNA and protein levels and suppresses hepatocytic lipid droplet formation. Importantly, the function of lnc-HC in regulating PPAR? expression depends on modulating miR-130b-3p expression from the transcriptional to the post-transcriptional level, not through lncRNA's critical modulating patterns. In vivo, the reduction of lnc-HC expression significantly decreases miR-130b-3p expression, induces PPAR? expression, and increases TG concentration in rat livers with hyperlipidemia. These findings further help in understanding the regulatory pattern of lnc-HC in hepatic lipid metabolism and might present a possible therapeutic target for improving lipid homeostasis.