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Objective:To explore the effect of miR-7 on the formation of abdominal aortic aneurysm by up-regulating the expression of ERK and MMP-9 proteins.Methods:Download the miRNAs expression profile chip data from the GEO database, the differentially expressed miRNAs were screened out by GEO2R and the correlation between target genes and ERK genes was analyzed; twenty 4-week male C57BL/6J mice with SPF grade were selected and randomly divided into a model group (only 0.6% BAPN solution was given, n=10) and miR-7 group (fed with 0.6% BAPN solution+ injected with 1×10 9 PFU/ml lentivirus containing miR-7 over expression gene via tail vein, n=10), after 7 weeks of continuous feeding, the mice were anesthetized intraperitoneally with chloral hydrate. After the abdominal cavity and thorax were dissected, the abdominal aorta was separated from the left ventricle perfusion with normal saline under physiological pressure and pathological sections were prepared. Masson staining and α-SMA staining were used to evaluate the lesion degree of abdominal aortic vessels in each group; the protein expression levels of p-ERK1/2 and MMP-9 in the diseased abdominal aorta of each group were detected by WB. Results:By screening differential genes, we found that miR-7 was highly expressed in patients with abdominal aortic aneurysm, and further analysis revealed that miR-7 was positively correlated with ERK1/2; Masson staining showed that the tumor of abdominal aortic aneurysm in miR -7 group was significantly larger than that in the model group, and the difference was statistically significant ( P<0.05), the results of α-SMA histochemical staining showed that the number of α-SMA positive VSMC in miR-7 group was significantly lower than that in the model group, and there was almost no-SMA staining in some VSMC; WB results showed that the highest expressions of P-ERK1/2 and MMP-9 proteins in the abdominal aorta of miR-7 group were significantly higher than that of the model group, with statistically significant differences ( P<0.05). Conclusion:MiR-7 accelerated the formation of abdominal aortic aneurysms by up-regulating the expression of ERK and MMP-9 proteins.
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@#Objective: To investigate the effect of long non-coding RNA CDKN2B antisense RNA 1 (CDKN2B-AS1) on malignant biological behaviors of melanoma B16-F10 cells by targeting miR-7-5p. Methods: Melanoma B16-F10 cells were chosen for this study. shRNA CDKN2B-AS1 vector was constructed and transfected into B16-F10 cells. The experimental cells were divided into control group, sh-CDKN2B-AS1 group, miR-7-5p mimic group and miR-7-5p inhibitor group. The expression level of CDKN2B-AS1 mRNA in the transfected B16-F10 cells was detected by RT-PCR; the number of clone formation and the proliferation ability of the cells were detected by Clone formation assay and MTT assay; and the migration and invasion ability of the cells were detected by Scratch-healing assay and Transwell assay. The targeting relationship between CDKN2B-AS1 and miR-7-5p was detected by Luciferase reporter gene assay. The mRNA expression of miR-7-5p and protein expressions of Ki67, cleaved caspase-3, E-cadherin, N-cadherin and Twist1 in B16-F10 cells after transfection with miR-7-5p mimics/inhibitor were detected by RT-PCR and Western blotting, respectively. Results: Compared with the control group, the expression level of CDKN2B-AS1 mRNA in B16-F10 cells of sh-CDKN2B-AS1 group was significantly decreased (P<0.01); the proliferation, migration and invasion ability of cells were significantly decreased (all P<0.01). Luciferase reporter gene assay showed that CDKN2B-AS1 directly targeted miR-7-5p. The mRNAexpression of miR-7-5p, and protein expressions of cleaved caspase-3 and E-cadherininsh-CDKN2B-AS1groupandmiR-7-5pmimic group were significantly up-regulated (all P<0.05), whiletheproteinexpressionsofKi67,N-cadherin,andTwist1weresignificantlydown-regulated (all P<0.05). Conclusion: CDKN2B-AS1 targets miR-7-5p to promote the development of melanoma, and interfering with CDKN2B-AS1 can inhibit the malignant biological behaviors of melanoma B16-F10 cells.
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Objective To investigate the effect and underlying mechanism of lncRNA MEG3 on the radiosensitivity of nasopharyngeal carcinoma cells.Methods this experiment,overexpression control group,MEG3 overexpression group,miR-NC inhibition group,miR-7-5p inhibition group,overexpression control+4 Gy group,MEG3 overexpression+4 Gygroup,miR-NC inhibition+4 Gy group,miR-7-5p inhibition+4 Gy group,MEG3 overexpression + miR-NC overexpression group,MEG3 overexpression + miR-7-Sp overexpression group were established.The expression of miR-7-5p and MEG3 was detected by qRT-PCR.The radiosensitivity of nasopharyngeal carcinoma cells was measured by clone formation assay.Cell apoptosis was assessed by flow cytometry.The fluorescence activity was evaluated by dual luciferase reporter assay.Results MEG3 was lowly expressed in nasopharyngeal carcinoma tissues and cells.Overexpression of MEG3 and inhibition of miR-7-5p expression increased the radiosensitivity of nasopharyngeal carcinoma cells and promoted radiation-induced cell apoptosis.MEG3 could targetedly regulate the miR-7-5p expression.Overexpression of miR-7-5p reversed the effect of overexpression of MEG3 on the sensitization of nasopharyngeal carcinoma cells and the promotion of apoptosis induced by radiation exposure.Conclusions Overexpression of MEG3 increases the radiosensitivity of nasopharyngeal carcinoma cells and promotes radiation-induced cell apoptosis.The mechanism may be related to the down-regulation of miR-7-5p expression.
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Objective The purpose of this study was to investigate the differential expression of microRNA in gefitinib acquired resistant lung cancer cells and non-resistant cells and their roles on cell growth.MethodsGefitinib resistant NSCLC A549 and H1299 cells were constructed. The cell activity was detected by CCK-8 assays. Real-time PCR was used to detect microRNA expression. The intracellular microRNA expression profile was detected by microarray. The transfection of miRNA-7 mimic was used to up-regulate the expression of mir-7. EGFR protein expression was detected by Western -blotting.ResultsThe IC50 value of gefitinib resistant cells was 3 fold than that of their parental cells. The drug-resistant cells grew slowly compared with their parental cells. 43 miRNA were significantly changed in the gefitinib resistant cells, including 25 up-regulated miRNA and 18 down-regulated miRNA. The IC50 was significantly decreased and the EGFR expression was negatively regulated after up-regulated of mir-7.ConclusionmiR-7 expression negatively regulates EGFR expression and decreased expression of miR-7 is one of the mechanisms leading to gefitinib resistance in non-small cell lung cancer cells.
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Objective To investigate the regulation of miR-7 on intestinal trefoil factor (TFF3) and its effect on the proliferation and migration of intestinal epithelial cells. Methods miR-7 mimics and miR-7 inhibitor were transfected into LS174T cells respectively. The experiment was divided into 5 groups,including blank control group,miR-7 mimic negative control group,miR-7 mimic group,miR-7 inhibitor negative con-trol group,miR-7 inhibitor group. MTT assay was used to detect cell proliferation. Cell scratch assay was used to detect the effect of miR-7 on cell migration. Western blot was used to detect the change of TFF3 protein in each group. Results Compared with the blank control group,the miR-7 mimic negative control group and the miR-7 inhibitor negative control group,the OD value of the miR-7 mimic group decreased significantly, the difference was statistically significant(P<0. 05); the cell scratch interval increased,the cell migration rate decreased,the difference was statistically significant( P<0. 05); and the TFF3 protein expression was accompanied(P<0. 05). The OD value of the miR-7 inhibitor group significantly increased,the difference was statistically significant(P<0. 05); the cell scratch gap decreased,the cell migration rate was enhanced, the difference was statistically significant( P <0. 05); and the expression of TFF3 protein increased ( P <0. 05). Conclusion miR-7 can regulate the expression of TFF3 and further inhibit the proliferation and migration of LS174T cells.
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Objective To investigate the effect of miR-7 on the migration ability of intestinal epithelial cells and its related mechanisms. Methods LS174T cells were transfected with miR-7 mimic and miR-7 inhib-itor respectively. The effect of miR-7 on cell migration ability was detected by transwell chamber. The changes of PI3K, p-Akt and Akt protein in each group were detected by Western Blot. Results Compared with the control group, miRNA mimic negative control group and miRNA inhibitor negative control group, the number of cells in the miR-7 mimic group through the tranwell chamber decreased, the cell migration rate decreased, and the expression of PI3K and p-Akt protein decreased at the same time, the difference was statistically signifi-cant (P<0. 05). In the miRNA inhibitor group, the number of cells in the tranwell chamber increased, the cell migration rate increased, and the expression of PI3K and p-Akt protein was increased at the same time, the difference was statistically significant (P<0. 05). Conclusion miR-7 can inhibit the migration of LS174T cells, which may be through the regulation of the PI3K/Akt signaling pathway.
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Aim To explore the effects of miR-7 on astrocyte activation and the underlying mechanisms. Methods Following isolation and culturing, astro-cytes extracted from rat cortex were treated with culture solution (control group), ciliary neurotrophic factor (CNTF, an agonist of astrocyte activation), miR-7 mimic+CNTF, miR-7 mimic control+CNTF, miR-7 inhibitor+CNTF and miR-7 inhibitor control+CNTF, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the mRNA ex-pression of glial fibrillary acidic protein (GFAP) and epidermal growth factor receptor(EGFR). The protein expression of GFAP, EGFR, signal transducers and activators of transcription 3(STAT3) and phosphoryla-ted STAT3 (p-STAT3) was measured using Western blot. Wild type pGL3-EGFR and mutant pGL3-EGFR-m recombinant plasmids were constructed and then co-transfected with miR-7 mimic into HEK293T cells,re-spectively. The luciferase activity of reporter gene was measured. In addition,astrocytes were treated with ei-ther EGFR siRNA or S31-201 (an inhibitor of STAT3),followed by the incubation with miR-7 inhib-itor and CNTF. Both qRT-PCR and Western blot were subsequently used to detect the mRNA and protein lev-els of GFAP. Results The expression levels of GFAP and EGFR as well as p-STAT3/STAT3 ratio in CNTF group were higher than those in control group (P <0.01). When compared with CNTF group,GFAP and EGFR levels and p-STAT3/STAT3 ratio significantly decreased in miR-7 mimic+CNTF group but increased in miR-7 inhibitor+CNTF group(P<0.01). In com-parison with control group, transfection with miR-7 mimic markedly reduced the luciferase activity of wild type EGFR (P <0.01). Moreover, miR-7 inhibitor-induced up-regulation of GFAP expression was almost completely reversed by either EGFR siRNA or S31-201 pretreatment (P<0.01). Conclusion miR-7 antag-onizes the activation of astrocytes from rats by inhibi-ting the EGFR/STAT3 signaling pathway.
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MicroRNA(miRNA)is a class of non-coding,endogenous RNA molecules.It has been confirmed in many studies that miRNA has aberrant expression in human tumors,which is related to the occurrence,progression and the response to treatment of various human tumors.MicroRNA-7(miR-7)is an important member of the miRNA family.Recent studies have reported that miR-7 is closely related to the occurrence,development,treatment and prognosis of endocrine malignant tumors such as thyroid cancer and pan -creatic cancer,indicating that it may serve as a potential molecular target for biological treatment of endocrine malignancies.The re-search progression in the relationship between miR-7 and thyroid cancer,as well as other endocrine malignant tumors are reviewed in this paper.
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OBJECTIVE: To investigate the mechanism of miR-7-5p in TK6 cell damage induced by hydroquinone( HQ) by constructing stable miR-7-5p over-expressing human lymphoblastoid TK6 cell line using lentivirus. METHODS: i) The miR-7-5p over-expression lentivirus vectors were constructed,and then infected to TK6 cells. The miR-7-5p overexpression stable TK6 cell line( TK6-miR-7-5p cells) and negative control cells( TK6-NC cells) were selected with puromycin. The infection efficiency was confirmed by real-time fluorescent quantitative polymerase chain reaction assay.ii) TK6,TK6-NC and TK6-miR-7-5p cells were treated with HQ at final concentrations of 0 and 40 μmol/L for 48 hours.Cell viability was determined by CCK-8 assay. The early apoptosis rate of cells was detected by flow cytometry. The relative expression of poly( ADP-ribose) polymerase-1( PARP-1) and breast cancer susceptibility gene 1( BRCA1) proteins in 3 kinds of cells treated with HQ at the final concentration of 40 μmol/L was detected by Western blotting. RESULTS: i) The TK6 cell line with stable expression of miR-7-5p were successfully screened. Compared with normal TK6 cells,the relative expression of miR-7-5p in TK6-miR-7-5p cells increased by about 17 times( P < 0. 01) with no significant changes in cell morphology. ii) After treatment with 40 μmol/L HQ,the survival rate of TK6-miR-7-5p cells decreased compared with normal TK6 cells and TK6-NC cells( P < 0. 01),early apoptosis rate increased( P < 0. 01),the relative expression of PARP-1 and BRCA1 protein was decreased( P < 0. 05). CONCLUSION: MiR-7-5p may lead to the increase of early apoptosis in TK6 cells induced by HQ through inhibiting the DNA damage repair capacity related to PARP-1 and BRCA1.
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MicroRNA-7(miR-7)was firstly found in Drosophila melanogaster,which participated in the formation of Drosophila wings,eggs and so on.In human being miR-7 is not only involved in cell prolifera-tion and differentiation,but also plays an important role in the development of tumor,especially in lung cancer. Most studies report that miR-7 is low expression in lung cancer with poor prognosis.Improving the expression of miR-7 can inhibit tumor growth.MiR-7 can regulate the expression of BCL-2,EGFR negatively,meanwhile it can regulate the sensitivity of tumor cells to radiotherapy chemotherapy and targeted therapy.Therefore,as a tumor suppressor,miR-7 is expected to become a new target for treatment of lung cancer.
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Objective:To detect the effect of microRNA-7 ( miR-7 ) knockdown on pathology in murine acute lung injury ( ALI) model,and preliminarily explore its significance.Methods:Murine ALI model was performed by intraperitoneal injection of Li-popolysaccharide (LPS) (10 mg/kg) into miR-7KD mice and wild-type (wild type,WT) mice respectively.Then,the pathologic injury of lung tissue were observed by HE staining.And total cell count of bronchoalveolarlavage(BAL) was calculated.The relative expression of related cytokines in lung tissue was analyzed by Real-time PCR assay.Furthermore,the changes on proportion of innate immune cells (γδT cell and F4/80 macrophages cell) and adaptive immune cell ( CD4+T cell and CD8+T cell) were analyzed by FACS.Meanwhile, the expression of CD62L and CD69,as well as the absolute number,in CD4+T cell were also analyzed.Results: Compared with WT mice,pathological damage in lung tissues was significantly alleviated in miR-7KD mice.Real-time PCR analysis showed that the relative expression of IL-6 was obviously reduced (P<0.01),conversely,relative expression of IL-4 and TGF-βwere obviously increased (P<0.05).Furthermore,the total cell number in BAL also reduced significantly (P<0.05).Importantly,FACS analysis showed that the proportion and the absolute number of F4/80+Mφcells obviously reduced (P<0.05);however,the proportion of γδT cells increased (P<0.05).Moreover,the proportion and the absolute number of CD4+T cells and CD8+T cells were significantly reduced (P<0.05). Finally, the proportion and the absolute number of CD62L+in CD4+T cells were upregulated vigorously,contrastly,the proportion and the absolute number of CD69+in CD4+T cells were notably up-regulated (P<0.05).Conclusion:miR-7 defeciency could significantly ameliorate the pathology of murine ALI,suggesting that it may play an important regulatory role in the development of ALI.
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Objective:To investigate the change of expression of miR-7 in activated CD4+ T cells in vitro, and preliminary explore its possible significance. Methods: CD4+CD62L+T cells was purified from splenocytes of FVB mice by magnetic cell sorting system (MACS). After stimulation with anti-CD3/CD28 antibody,the relative expression of miR-7 was examined by Real-time PCR, and the expression level of CD69 molecular was analyzed by FACS. Furthermore,the relative expression of miR-7 in CD4+T cells was detected at different time points during stimulation. With the treatment of ERK inhibitor PD98059,change of miR-7 expression was de-termined by Real-time PCR. Meanwhile, the proliferation of CD4+T cells was examined by CCK-8 assay and the expression level of CD69 and CD62L molecular were analyzed by FACS. Finally,the expression of cytokines IL-6,IL-10,and IFN-γ were determined by Real-time PCR. Results:Compared with control group,the relative expression of miR-7 was increased significantly after stimulation with anti-CD3/CD28 antibody,as well as expression level of CD69 molecular was augmented(P<0. 05). In contrasted with 0 h and 24 h,the expression of miR-7 was significantly increased after 48 h and 72 h during stimulation(P<0. 05). Furthermore,the relative expression of miR-7 was significantly declined in CD4+T cells in ERK inhibitor PD98059 treatment group. Finally, the expression level of CD69 molecular,as well as cytokines IL-6, IL-10 and IFN-γ, were also decreased significantly ( P<0. 05 ) . Conclusion: The relative expression of miR-7 was significantly increased in activated CD4+T cells,closely related to ERK pathway,which provided an important foundation for successive research work on exploring the functional role of miR-7 in the CD4+T cells.
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Objective:To detect the change of proportions of αβT lymphocytes in mesenteric lymph nodes of miR-7 knockdown (miR-7KD)mice,and preliminarily explore its importance.Methods: The volume,weight index and total cells number of mesenteric lymph node in miR-7KD mice were measured.The pathologic morphology change of mesenteric lymph nodes was observed by HE stai -ning.And the changes on proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice were analyzed by Flow cytometry.Results:Compared with those of WT (wild type) mice,the volume,weight index,and the total cells number of mesenteric lymph node were significantly increased ( P<0.05 ).Moreover ,the pathologic morphology was significantly changed.The proportion and numbers of T lymphocyte were significantly increased;however,the proportion of B lymphocyte were significantly decreased (P<0.05). Notably,the proportion and number of CD4+T cells and CD8+T cells were significantly increased (P<0.05).Meanwhile,CD62L+T cell proportion were vigorously reduced and CD 69+T cell and IFN-γ+T cell proportion were notably up-regulated,which belong to CD4+and CD8+T cell(P<0.05).Conclusion:There was significant influence in the proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice,suggesting that miR-7 might play an important role in the composition and function of lymphocytes in mesenteric lymph nodes.
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Epstein-Barr virus (EBV)-encoded small non-coding RNAs (EBERs) are abundantly expressed in various EBV-associated malignancies, and play critical roles in cell proliferation, tumorigenesis, and apoptosis resistance. However, the mechanism how EBERs regulate cell function awaits further clarification. In this study, we investigated the effect of EBERs on the expression of cellular microRNA (miRNA) and mRNA expression. To test the effect of EBERs while unaffected by other EBV genes, we used EBERs-deleted recombinant EBV infected Burkitt's lymphoma cell line (Akata(+)EBERs(-)) as well as EBV-infected (Akata(+)) and EBV uninfected (Akata(-)) cell lines. They all have the same genetic backgrounds. First, 15 different cellular miRNAs which have reverse complementary sequences to EBERs and have reported targets were selected by bioinformatics analysis. When RT-PCR was carried out for the 16 miRNAs using RNAs from Akata(+), Akata(-), and Akata(+)EBERs(-) cells, hsa-miR-7-5p was the only one showing down-regulated expression in Akata(+) than in Akata(-) and Akata(+)EBERs(-) cells. Bioinformatics and mRNA microarray analyses for Akata(+), Akata(-), and Akata(+)EBERs(-) cell lines were then carried out to predict putative targets of hsa-miR-7-5p. Among the 6 predicted targets of hsa-miR-7-5p, only low density lipoprotein receptor-related protein 6 (LRP6) was up-regulated in EBERs-expressing cells when tested by RT-PCR and Western blot. However, luciferase reporter assay showed that the 3'-UTR of LRP6 was not directly targeted by hsa-miR-7-5p. Our data suggest that both hsa-miR-7-5p and LRP6 are regulated by EBERs in Akata cells, and these genes may partly mediate the tumorigenic function of EBERs in Burkitt's lymphoma.
Subject(s)
Apoptosis , Blotting, Western , Burkitt Lymphoma , Carcinogenesis , Cell Line , Cell Proliferation , Computational Biology , Herpesvirus 4, Human , Low Density Lipoprotein Receptor-Related Protein-6 , Luciferases , MicroRNAs , RNA , RNA, Messenger , RNA, Small UntranslatedABSTRACT
MicroRNAs (miRNAs) are a class of regulatory RNAs that control the expression of genes critical to cell function. Ectopic expression of miRNAs has been shown to result in genome-wide changes in patterns of gene expression. While the reasons for these global alterations in gene expression patterns have been attributed to the ability of miRNAs to target multiple genes, and/or to induce indirect effects downstream of target genes, the molecular basis of indirect effects of miRNA regulation remains poorly understood. In this study, we demonstrate the potential of miRNAs to regulate other miRNAs. Using miRNA microarray analysis, we show that over 70 different miRNAs are differentially expressed (≥1.4 fold, FDR≤5%) in human ovarian cancer cells after transfection with a single miRNA (miR-7). We present evidence that a major component of miR-7 induced changes in levels of miRNAs is the indirect consequence of miR-7 mediated alterations in levels of protein coding genes (e.g., transcription and splicing factors) that exert trans-regulatory control on miRNAs.