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1.

Background

Colorectal carcinoma (CRC) is one of the leading causes of cancer-related mortality worldwide. MicroRNAs (miRNAs, miRs) play important roles in carcinogenesis. MiR-126 has been shown to be down-regulated in CRC. In this study, we identified the potential effects of miR-126 on some important biological properties of CRC cells and clarified the regulation of insulin receptor substrate 1 (IRS-1) and its possible signaling pathway by miR-126.

Methods

The effect of miR-126 on IRS-1, AKT, and ERK1/2 expression was assessed in the CRC cell lines HT-29 and HCT-116 with a miR-126 mimic or inhibitor to increase or decrease miR-126 expression. Furthermore, the roles of miR-126 in regulation of the biological properties of CRC cells were analyzed with miR-126 mimic or inhibitor-transfected cells. The 3′-untranslated region (3′-UTR) of IRS-1 regulated by miR-126 was analyzed by using a dual-luciferase reporter assay.

Results

We found that IRS-1 is the functional downstream target of miR-126 by directly targeting the 3′-UTR of IRS-1. Endogenous miR-126 and exogenous miR-126 mimic inhibited IRS-1 expression. Furthermore, gain-of-function or loss-of-function studies showed that over-expression of miR-126 down-regulated IRS-1, suppressed AKT and ERK1/2 activation, CRC cells proliferation, migration, invasion, and caused cell cycle arrest, but had no effect on cell apoptosis. Knockdown of miR-126 promoted these processes in HCT-116 cells and promoted AKT and ERK1/2 activation by up-regulating the expression of the IRS-1 protein.

Conclusions

MiR-126 may play roles in regulation of the biological behavior of CRC cells, at least in part, by targeting IRS-1 via AKT and ERK1/2 signaling pathways.  相似文献   

2.
《Cellular signalling》2014,26(6):1347-1354
S1PR1 plays a crucial role in promoting proliferation of hepatocellular carcinoma (HCC). Over expression of S1PR1 is observed in HCC cell lines. The mechanisms underlying the aberrant expression of S1PR1 are not known well. MircroRNAs are important regulators of gene expression and disproportionate microRNAs can result in dysregulation of oncogenes in cancer cells. In this study, we found that miR-363, a potential tumor suppressor microRNA, downregulated the expression of S1PR1 and inhibited the proliferation of HCC cells. Bioinformatic analysis predicted a putative binding site of miR-363 within the 3′-UTR of S1PR1 mRNA. Luciferase reporter assay showed that miR-363 directly targeted the 3′-UTR of S1PR1 mRNA. Transfection of miR-363 mimics suppressed S1PR1 expression in HCC cells, followed by the repression of the activation of ERK and STAT3. Moreover, we found that the expression of downstream genes of ERK and STAT3, including PDGF-A, PDGF-B, MCL-1 and Bcl-xL, was suppressed after miR-363 transfection. Taken together, the present study demonstrated that miR-363 was a negative regulator of S1PR1 expression in HCC cells and inhibited cell proliferation, suggesting that the miR-363/S1PR1 pathway might be a novel target for the treatment of HCC.  相似文献   

3.
Cholesteatoma is a destructive and abnormal skin growth consisting of keratinizing squamous epithelium in the middle ear. Its molecular mechanisms remain poorly understood. Here, we found that the NF-κB inflammatory signaling pathway was highly activated in cholesteatoma. NF-κB activation increased the expression of microRNA-802 (miR-802) and chromatin immunoprecipitation assays showed that P65 could uniquely bind to miR-802 promoter. miR-802 overexpression promoted keratinocyte cell proliferation and cell cycle progression, while inhibition of miR-802 decreased these effects. From computational analysis and luciferase report assays, miR-802 directly repressed PTEN expression by targeting its 3′-UTR. Our results demonstrate that the NF-κb/miR-802/PTEN signaling pathway plays an important role in the development of cholesteatoma.  相似文献   

4.
Glioma is the most aggressive malignant tumor in the adult central nervous system. Abnormal long noncoding RNA (lncRNA) FOXD2-AS1 expression was associated with tumor development. However, the possible role of FOXD2-AS1 in the progression of glioma is not known. In the present study, we used in vitro and in vivo assays to investigate the effect of abnormal expression of FOXD2-AS1 on glioma progression and to explore the mechanisms. FOXD2-AS1 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of FOXD2-AS1 was correlated with poor prognosis of glioma. Downregulation of FOXD2-AS1 decreased cell proliferation, migration, invasion, stemness, and epithelial-mesenchymal transition (EMT) in glioma cells and inhibited tumor growth in transplanted tumor. We also revealed that FOXD2-AS1 was mainly located in cytoplasm and microRNA (miR)-185-5p both targeted FOXD2-AS1 and CCND2 messenger RNA (mRNA) 3′-untranslated region (3′-UTR). miR-185-5p was downregulated in glioma tissue, cells, and sphere subpopulation. Downregulation of miR-185-5p was closely correlated with poor prognosis of glioma patients. In addition, miR-185-5p mimics decreased cell proliferation, migration, invasion, stemness, and EMT in glioma cells. CCND2 was upregulated in glioma tissue, cells, and sphere subpopulation. Upregulation of CCND2 was closely correlated with poor prognosis of glioma patients. CCND2 knockdown decreased cell proliferation, migration, invasion, and EMT in glioma cells. In glioma tissues, CCND2 expression was negatively associated with miR-185-5p, but positively correlated with FOXD2-AS1. FOXD2-AS1 knockdown and miR-185-5p mimics decreased CCND2 expression. Inhibition of miR-185-5p suppressed FOXD2-AS1 knockdown-induced decrease of CCND2 expression. Overexpression of CCND2 suppressed FOXD2-AS1 knockdown-induced inhibition of glioma malignancy. Taken together, our findings highlight the FOXD2-AS1/miR-185-5p/CCND2 axis in the glioma development.  相似文献   

5.
Glioma proliferation is a multistep process during which a sequence of genetic and epigenetic alterations randomly occur to affect the genes controlling cell proliferation, cell death and genetic stability. microRNAs are emerging as important epigenetic modulators of multiple target genes, leading to abnormal cellular signaling involving cellular proliferation in cancers.In the present study, we found that expression of miR-195 was markedly downregulated in glioma cell lines and human primary glioma tissues, compared to normal human astrocytes and matched non-tumor associated tissues. Upregulation of miR-195 dramatically reduced the proliferation of glioma cells. Flow cytometry analysis showed that ectopic expression of miR-195 significantly decreased the percentage of S phase cells and increased the percentage of G1/G0 phase cells. Overexpression of miR-195 dramatically reduced the anchorage-independent growth ability of glioma cells. Furthermore, overexpression of miR-195 downregulated the levels of phosphorylated retinoblastoma (pRb) and proliferating cell nuclear antigen (PCNA) in glioma cells. Conversely, inhibition of miR-195 promoted cell proliferation, increased the percentage of S phase cells, reduced the percentage of G1/G0 phase cells, enhanced anchorage-independent growth ability, upregulated the phosphorylation of pRb and PCNA in glioma cells. Moreover, we show that miR-195 inhibited glioma cell proliferation by downregulating expression of cyclin D1 and cyclin E1, via directly targeting the 3′-untranslated regions (3′-UTR) of cyclin D1 and cyclin E1 mRNA. Taken together, our results suggest that miR-195 plays an important role to inhibit the proliferation of glioma cells, and present a novel mechanism for direct miRNA-mediated suppression of cyclin D1 and cyclin E1 in glioma.  相似文献   

6.
Glioblastomas (GBM), the most common and aggressive type of malignant glioma, are characterized by increased invasion into the surrounding brain tissues. Despite intensive therapeutic strategies, the median survival of GBM patients has remained dismal over the last decades. In this study we examined the expression of miR-145 in glial tumors and its function in glioma cells. Using TCGA analysis and real-time PCR we found that the expression of miR-145/143 cluster was downregulated in astrocytic tumors compared to normal brain specimens and in glioma cells and glioma stem cells (GSCs) compared to normal astrocytes and neural stem cells. Moreover, the low expression of both miR-145 and miR-143 in GBM was correlated with poor patient prognosis. Transfection of glioma cells with miR-145 mimic or transduction with a lentivirus vector expressing pre-miR 145 significantly decreased the migration and invasion of glioma cells. We identified connective tissue growth factor (CTGF) as a novel target of miR-145 in glioma cells; transfection of the cells with this miRNA decreased the expression of CTGF as determined by Western blot analysis and the expression of its 3′-UTR fused to luciferase. Overexpression of a CTGF plasmid lacking the 3′-UTR and administration of recombinant CTGF protein abrogated the inhibitory effect of miR-145 on glioma cell migration. Similarly, we found that silencing of CTGF decreased the migration of glioma cells. CTGF silencing also decreased the expression of SPARC, phospho-FAK and FAK and overexpression of SPARC abrogated the inhibitory effect of CTGF silencing on cell migration. These results demonstrate that miR-145 is downregulated in glial tumors and its low expression in GBM predicts poor patient prognosis. In addition miR-145 regulates glioma cell migration by targeting CTGF which downregulates SPARC expression. Therefore, miR-145 is an attractive therapeutic target for anti-invasive treatment of astrocytic tumors.  相似文献   

7.
Oral squamous cell carcinoma (OSCC), the most common pathological type of oral cancer, is still a frequent malignancy with unsatisfactory prognosis. Accumulating studies have proven some microRNAs (miRNAs) can function as oncogenes in OSCC by targeting tumor suppressors. In this study, we first investigated the expression and role of tumor suppressor bridging integrator-1 (BIN1) in OSCC tissues and cells. Our results indicated that BIN1 was low expressed in the OSCC tissues and cell lines (SCC6, SCC9, SCC25, HN4, and HN6) along with miR-211 was highly expressed in OSCC tissues and cell lines, and BIN1 overexpression could evidently inhibit their proliferation, migration, and invasion abilities. Next, we used bioinformation algorithms to predict the potential miRNA targeting BIN1 and chose miR-211 for further study. miR-211, a highly expressed miRNA in OSCC cells, could specifically bind with the 3′-untranslated region (3′-UTR) of BIN1 to trigger its degradation. Addition of miR-211 inhibitor could evidently suppress the malignant behaviors of OSCC cells by upregulating BIN1 expression and inhibit the activation of the EGFR/MAPK pathway. Taken together the findings of the study indicated that miR-211 mediated BIN1 downregulation had crucial significances in OSCC, suggesting the miR-211 might be a novel potential therapeutic target for the OSCC treatment.  相似文献   

8.
Mounting evidence showed that microRNAs involve in development and chemoresistance of various human cancers. We explored the roles and mechanisms of miR-144 in resistance to cisplatin (CDDP) of cervical cancer cells. miR-144 and LIM homeobox 2 (LHX2) expression in CDDP-resistant and the parental cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis, respectively. The functions of miR-144 overexpression on cell viability, the incidence of apoptosis, the activity of caspase-3/7, the cleaved-caspase-3 expression, cell migration, and invasion were determined in Hela cells and Hela/CDDP cells. Overexpression of miR-144 reduced cell viability, induced cell apoptosis, and inhibited cell migration and invasion after CDDP treatment. Besides, a luciferase reporter system demonstrated that miR-144 could directly bind to the 3′ untranslated region (3′-UTR) of LHX2 messenger RNA (mRNA). Gain expression of miR-144 decreased the expression of LHX2 both in mRNA and protein levels. Furthermore, restoration of LHX2 partly abolished the biological functions of miR-144 in resistance of cervical cancer cells. Taken together, miR-144 overcomes resistance to CDDP via promoting cell apoptosis and inhibiting invasion through targeting LHX2 in cervical cancer cells.  相似文献   

9.
Increasing evidence suggests that hsa-miR-126 (miR-126) is down-regulated in non-small cell lung cancer (NSCLC) cell lines and the restoration of miR-126 impairs tumor cell proliferation, migration, invasion, and survival by targeting specific molecules. Here, we reported for the first time that miR-126 was involved in regulating the response of NSCLC cells to cancer chemotherapy. After transfected A549 cells with miR-126 mimic or inhibitor, we found that an elevated level of miR-126 was significantly associated with a decreased half maximal inhibitory concentration of adriamycin (ADM) and vincristine, an increased accumulation of ADM, down-regulation of vascular endothelial growth factor A (VEGFA) and multidrug resistance-associated protein 1 (MRP1), and inactivation of the Akt signaling pathway. Furthermore, enhanced expression of miR-126 suppressed the growth of A549 xenograft and inhibited the expression of VEGFA and MRP1. miR-126 could efficiently down-regulate VEGFA expression through the interaction with the VEGFA 3'-untranslated region, whereas restoration of VEGFA could partially attenuate the suppression of MRP1 by miR-126. However, LY294002, an inhibitor of the PI3K/Akt signaling pathway, diminished this effect, suggesting that enhanced expression of miR-126 increased the sensitivity of NSCLC cells to anticancer agents through negative regulation of a VEGF/PI3K/Akt/MRP1 signaling pathway.  相似文献   

10.

Objective

To elucidate the molecular mechanism of microRNA-215 (miR-215) in the migration and invasion of high grade glioma.

Results

42 Patients were analysed for clinicopathological characteristics. qRT-PCR showed that miR-215 was up-regulated in glioma tissues compared with non-neoplastic brain tissues (P < 0.05). The up-regulated miR-215 was closely associated with high grade glioma (P < 0.01) and poor overall survival (P < 0.01). Transwell assay showed that re-expression of miR-215 enhanced migration and invasion of glioma cells. miR-215 also down-regulated retinoblastoma tumor suppressor gene 1 (RB1) expression by targeting its 3′-UTR. Reversely, re-expression of RB1 inhibited partial effect of miR-215 on migration and invasion in vitro.

Conclusions

Re-expression of miR-215 promoted cell migration and invasion of glioma by targeting RB1. miR-215 can thus be used as a biomarker for tumor progression and prognosis in human high grade glioma.
  相似文献   

11.
12.
13.

Objective

To evaluate the role and the molecular mechanism of miR-30d in non-small cell lung cancer (NSCLC).

Results

qRT-PCR was used to detect miR-30d expression in NSCLC tissues and cell lines. miR-30d was frequently down-regulated in NSCLC and its expression was associated with clinicopathological features of NSCLCC patients. Over-expression of miR-30d notably inhibited cell migration and invasion in NSCLC cell lines. miR-30d could negatively regulate Nuclear factor I B (NFIB) by directly targeting its 3′-UTR, which was confirmed by luciferase assay. NFIB also reversed miR-30d-mediated suppression on the migration and invasion in NSCLC cell lines.

Conclusion

miR-30d suppressed cell migration and invasion by directly targeting NFIB in NSCLC, and NFIB could partially abrogated the inhibition of biological functions by miR-30d.
  相似文献   

14.
Colorectal cancer is considered as the fourth leading reason of cancer-linked deaths worldwide. However, our knowledge about its pathogenic mechanism remains inadequate. MicroRNA 32 (miR-32), a member of small noncoding RNAs, has been found vital roles in tumorigenesis. This study studied its functions and underlying mechanism in colorectal cancer. The experiment revealed the obvious upregulation of miR-32 in colorectal cancer tissues and six cancer cell lines, compared with normal tissues and cells. Moreover, miR-32 upregulation reduced cell apoptosis and promoted cell proliferation and migration, while its downregulation displayed opposite effects. Dual luciferase reporter assays proved that miR-32 bound to the 3′-untranslated region (3′-UTR) of OTU domain containing 3 (OTUD3), suggesting that miR-32 directly targeted OTUD3. Further experiments demonstrated that overexpression of miR-32 could reduce the expression level of OTUD3. Furthermore, OTUD3 silence promoted proliferation and motility and decreased apoptosis for HCT116 cells and restored partly miR-32-mediated cell proliferation, migration, and antiapoptosis for colon cancer. Therefore, our study indicated that miR-32 enhanced cell proliferation and motility abilities, and inhibited apoptosis by directly targeting OTUD3 in colon cancer cells, which implied that miR-32 was hopeful to be a biomarker or target used for diagnosis and therapy of colon cancer.  相似文献   

15.
16.
High expression of special AT-rich-binding protein 1 (SATB1) correlates with the advanced TNM stage and short overall and recurrence-free survival of gastric cancer (GC). A bioinformatic analysis revealed that SATB1 3′-untranslated region (3′-UTR) and long noncoding RNA UCA1 (lncRNA-UCA1) might competitively bind to microRNA-495-3p (miR-495-3p). Interestingly, lncRNA-UCA1 is also an important contributor to GC. The current study aimed to demonstrate the potential interaction among SATB1/miR-495-3p/lncRNA-UCA1 network and their effects on GC proliferation and invasion. The expression in GC and paracancerous normal tissues were assessed using real-time polymerase chain reaction and Western blot analysis. Luciferase reporter, RNA pull-down, and transfection assays were performed to determine the interaction among SATB1/miR-495-3p/lncRNA-UCA1 network in GC cells. GC proliferation and invasion were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, transwell invasion, and colony formation assays. Results showed higher expression of SATB1 and lncRNA-UCA1 but lower miR-495-3p expression in GC than in the normal tissues. In luciferase reporter assay, miR-495-3p bound to three seed sequences in SATB1 3′-UTR but only one in lncRNA-UCA1. SATB1 knockdown increased the combination of miR-495-3p with lncRNA-UCA1 but decreased lncRNA-UCA1 expression. Decreased lncRNA-UCA1 was also observed with the mimics increased miR-495-3p. These data suggested that SATB1 3′-UTR functions as a competing endogenous RNA of miR-495-3p and positively regulates lncRNA-UCA1. LncRNA-UCA1 knockdown only decreased SATB1 expression in MKN-45 cells but not in BGC-823 cells, which suggested that the regulatory effect of lncRNA-UCA1 on SATB1 by sponging miR-495-3p is cell-dependent. This study further identified that SATB1/miR-495-3p/lncRNA-UCA1 network is implicated in GC proliferation and invasion. The current study firstly revealed that SATB1 interacts with miR-495-3p/lncRNA-UCA1 network, whereby enhancing GC proliferation and invasion.  相似文献   

17.
In varicose veins, vascular smooth muscle cells (VSMCs) often show abnormal proliferative and migratory rates and phenotypic transition. This study aimed to investigate whether microRNA (miR)-202 and its potential target, peroxisome proliferator–activated receptor-γ coactivator-1α (PGC-1α), were involved in VSMC phenotypic transition. miR-202 expression was analyzed in varicose veins and in VSMCs conditioned with platelet-derived growth factor. The effect of miR-202 on cell proliferation and migration was assessed. Furthermore, contractile marker SM-22α, synthetic markers vimentin and collagen I, and PGC-1α were analyzed by Western blot analysis. The modulation of PGC-1α expression by miR-202 was also evaluated. In varicose veins and proliferative VSMCs, miR-202 expression was upregulated, with decreased SM-22α expression and increased vimentin and collagen I expression. Transfection with a miR-202 mimic induced VSMC proliferation and migration, whereas a miR-202 inhibitor reduced cell proliferation and migration. miR-202 mimic constrained luciferase activity in HEK293 cells that were cotransfected with the PGC-1α 3′-untranslated region (3′-UTR) but not those with mutated 3′-UTR. miR-202 suppressed PGC-1α protein expression, with no influence on its messenger RNA expression. PGC-1α mediated VSMC phenotypic transition and was correlated with reactive oxygen species production. In conclusion, miR-202 affects VSMC phenotypic transition by targeting PGC-1α expression, providing a novel target for varicose vein therapy.  相似文献   

18.

Objectives

To explore the effects of the competitive endogenous RNA (ceRNA) network between TP53INP1 and E-cadherin on the invasion and migration of glioma.

Results

TP53INP1 and E-cadherin mRNA and protein were significantly overexpressed in normal brain tissues compared with glioma tissue specimens and correlated with the grades of glioma negatively. The expression of TP53INP1 and E-cadherin were correlated positively. Patients with higher TP53INP1 or E-cadherin expression had longer overall survival. Moreover, TP53INP1 3′-UTR inhibited glioma cell proliferation, invasion and proliferation; Furthermore, the 3′-UTRs of TP53INP1 and E-cadherin harboured seven identical miRNAs binding sites, and TP53INP1 3′-UTR could increase the expression of E-cadherin and decrease the expression of vimentin thus repressing the epithelial-mesenchymal transition (EMT). However, the coding sequence of TP53INP1 could not increase the expression of E-cadherin and the inhibitory effect on EMT of TP53INP1 3′-UTR was reversed by the siRNA against Dicer.

Conclusions

TP53INP1 3′-UTR could inhibit the EMT, thus hindering the migration and invasion of glioma via acting as a ceRNA for E-cadherin.
  相似文献   

19.

Objectives

To clarify the potential biological function of miR-93 and its related molecular mechanism underlying metastasis in human hepatocellular carcinoma (HCC).

Results

miR-93 was significantly up-regulated in HCC tissues and was associated with poor 5-year overall survival in HCC patients. Transwell assays showed that over-expression of miR-93 increased HCC cell migration and invasion in vitro. Programmed cell death 4 (PDCD4) was a target gene of miR-93 and miR-93 could down-regulate the expression of PDCD4 by directly targeting its 3′-UTR. The re-expression of PDCD4 could attenuate the HCC cell invasion and migration induced by miR-93, while the knockdown of PDCD4 would promote HCC cell migration and invasion via the epithelial-mesenchymal transition (EMT) pathway.

Conclusions

miR-93 provides new insight into the molecular mechanisms of pathogenesis and progression in HCC and offer a potential therapeutic target for the treatment of HCC patients.
  相似文献   

20.
p72 is the member of the DEAD-box RNA helicase family, which can unwind double-stranded RNA and is efficient for microRNA (miRNA, miR) processing. However, its specific role in glioma has not been elucidated. First, the expression of p72 in glioma cell lines and tissues was explored using Western blot. To explore the role of p72 on glioma progression, adenovirus inhibiting p72 was transfected into A172 and T98G cells. Cell autophagy was determined using GFPLC3 dots, and cell apoptosis was determined using flow cytometry. The effect of Beclin1 was explored using GFP-LC3 dots, flow cytometry, and colony formation. The possible miRNAs that target the 3′-untranslated region (3′-UTR) of Beclin1 were predicted using TargetScan. Dual luciferase reporter assay was applied to determine whether these miRNAs bind to the 3′-UTR of Beclin1. The expression of p72 was significantly increased in glioma cell lines and tissues. Autophagy-related protein Beclin1 was found to be significantly enhanced when p72 was inhibited. The accumulation of GFP-LC3 dots was significant in cells transfected with ad-sh-p72 compared with ad-con. Colony formation capacity and cell apoptosis were also found to be significantly decreased with p72 inhibition. Furthermore, upregulation of Beclin1 contributes to A172 cell autophagy, invasion, and apoptosis. Overexpression of p72 induces increased miR-34-5p and miR-5195-3p expression in A172 and T98G cells. Beclin1 was the target gene of miR-34-5p and miR-5195-3p. In conclusion, we found for the first time that overexpression of p72 decreased Beclin1 expression partially by increasing miR-34-5p and miR-5195-3p expression in A172 and T98G cells.  相似文献   

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