MiR-340 mediates the involvement of high mobility group box 1 in the pathogenesis of liver fibrosis / 中华肝脏病杂志

Objective: To explore the pathogenic mechanism of the miR-340/high mobility group box 1 (HMGB1) axis in the formation of liver fibrosis. Methods: A rat liver fibrosis model was established by injecting CCl(4) intraperitoneally. miRNAs targeting and validating HMGB1 were selected with gene microarrays after screening the differentially expressed miRNAs in rats with normal and hepatic fibrosis. The effect of miRNA expressional changes on HMGB1 levels was detected by qPCR. Dual luciferase gene reporter assays (LUC) was used to verify the targeting relationship between miR-340 and HMGB1. The proliferative activity of the hepatic stellate cell line HSC-T6 was detected by thiazolyl blue tetrazolium bromide (MTT) assay after co-transfection of miRNA mimics and HMGB1 overexpression vector, and the expression of extracellular matrix (ECM) proteins type I collagen and α-smooth muscle actin (SMA) was detected by western blot. Statistical analysis was performed by analysis of variance and the LSD-t test. Results: Hematoxylin-eosin and Masson staining results showed that the rat model of liver fibrosis was successfully established. Gene microarray analysis and bioinformatics prediction had detected eight miRNAs possibly targeting HMGB1, and animal model validation had detected miR-340. qPCR detection results showed that miR-340 had inhibited the expression of HMGB1, and a luciferase complementation assay suggested that miR-340 had targeted HMGB1. Functional experiments results showed that HMGB1 overexpression had enhanced cell proliferation activity and the expression of type I collagen and α-SMA, while miR-340 mimics had not only inhibited cell proliferation activity and the expression of HMGB1, type I collagen, and α-SMA, but also partially reversed the promoting effect of HMGB1 on cell proliferation and ECM synthesis. Conclusion: miR-340 targets HMGB1 to inhibit the proliferation and ECM deposition in hepatic stellate cells and plays a protective role during the process of liver fibrosis.

The Biological Role of miR-340 in Colorectal Cancer Cells and the Regulatory Mechanism of Target Genes / 中国生物化学与分子生物学报

miR-340 can promote the proliferation and invasion of cancer cells, but how miR-340 regulates the occurrence and development of cancer in colon cancer is rarely reported. This study aims to explore the biological function and target gene regulation mechanism of miR-340 in colorectal cancer cells. Firstly, RT-qPCR was used to detect the expression level of miR-340 in different colorectal cancer cell lines, and then miR-340 was overexpressed or inhibited in COLO-205 cells. CCK-8, Transwell migration and invasion assay, and flow cytometry were performed to analyze the cell ability of proliferation, migration and invasion, as well as cell apoptosis and cell cycle. Finally, after bioinformatics prediction of miR-340 target genes, luciferase reporter gene and Western blot experiment were applied to verify those target genes. The results showed that miR-340 was downregulated in COLO-205 cells. Compared with the control group, cell proliferation, migration and invasion were significantly inhibited in the miR-340 overexpression group, but were promoted in the miR-340 suppression group (P<0. 01). The results of flow cytometry showed that the percentage of apoptosis in the miR-340 overexpression group was significantly increased, while the percentage of apoptosis in the miR-340 inhibition group was decreased (P<0. 01). The bioinformatics analysis of the overexpression miR-340 transfection group showed that the 3′UTR of glucose regulated protein 78 kD (GRP78) had a miR-340-5p binding site, and the luciferase activity was significantly reduced in the overexpression miR-340 group (P<0. 01); Western blot results also showed that overexpression of miR-340 can inhibit the expression of GRP78, while inhibiting miR-340 expression, the expression of GRP78 is relieved. In summary, miR-340 can directly target GRP78 to promote the apoptosis of COLO-205 cells and inhibit their proliferation, migration and invasion.

Effect of miR-340-5p on proliferation of laryngeal cancer Hep2 cells and its intrinsic molecular mechanism / 临床耳鼻咽喉头颈外科杂志

Objective@#To study the effect of miR-340-5p on the proliferation of laryngeal cancer Hep2 cells and explore its intrinsic molecular mechanism, so as to screen potential biomarkers and targets for the diagnosis and treatment of laryngeal cancer. @*Method@#The expression of miR-340-5p in laryngeal cancer tissues, paracancerous tissues, laryngeal cancer cell lines Hep2 and normal bronchial HBE cell lines was quantitatively analyzed by qRT-PCR; The double luciferase reporter vector was constructed to verify whether STAT3 was a potential target gene of microRNA-340-5p; The miR-340-5p mimics/inhibitor was transfected into Hep2 cells by liposome and verified by qRT-PCR; The CCK-8 method and Annexin V/PI method were used to analyze the proliferation and apoptosis of transfected cells; and Western Blot was used to detect the expression of STAT3 and Wnt/β-catenin pathway-related proteins after transfection. @*Result@#The results of qRT-PCR showed that the level of miR-340-5p in laryngeal cancer tissues and Hep2 cells was significantly lower than that in adjacent tissues and HBE cells, and the expression of miR-340-5p was significantly increased or decreased after overexpression or inhibition; Luciferase activity showed that miR-340-5p directly interacted with target gene STAT3 3'-UTR and negatively regulated its expression; Cell proliferation and apoptosis analysis showed that up-regulation of microRNA-340-5p could significantly inhibit the proliferation and induce apoptosis of Hep2 cells in vitro, and vice versa; Western Blot results showed that the levels of STAT3 and β-catenin, c-Myc, TCF-4, CyclinD1 and ROCK1 in Hep2 cells were significantly lower than those in the control group after over-expression of miR-340-5p, and vice versa. @*Conclusion@#The expression of miR-340-5p is abnormally low in laryngeal cancer tissues and Hep2 cells. It can be used as a potential biological target for diagnosis and treatment of laryngeal cancer by targeting STAT3 gene to negatively regulate Wnt/β-catenin signaling pathway.

Effect of miR-340-5p on proliferation of laryngeal cancer Hep2 cells and its intrinsic molecular mechanism / 临床耳鼻咽喉头颈外科杂志

To study the effect of miR-340-5p on the proliferation of laryngeal cancer Hep2 cells and explore its intrinsic molecular mechanism, so as to screen potential biomarkers and targets for the diagnosis and treatment of laryngeal cancer. The expression of miR-340-5p in laryngeal cancer tissues, paracancerous tissues, laryngeal cancer cell lines Hep2 and normal bronchial HBE cell lines was quantitatively analyzed by qRT-PCR; The double luciferase reporter vector was constructed to verify whether STAT3 was a potential target gene of microRNA-340-5p; The miR-340-5p mimics/inhibitor was transfected into Hep2 cells by liposome and verified by qRT-PCR; The CCK-8 method and Annexin V/PI method were used to analyze the proliferation and apoptosis of transfected cells; and Western Blot was used to detect the expression of STAT3 and Wnt/β-catenin pathway-related proteins after transfection. The results of qRT-PCR showed that the level of miR-340-5p in laryngeal cancer tissues and Hep2 cells was significantly lower than that in adjacent tissues and HBE cells, and the expression of miR-340-5p was significantly increased or decreased after overexpression or inhibition; Luciferase activity showed that miR-340-5p directly interacted with target gene STAT3 3'-UTR and negatively regulated its expression; Cell proliferation and apoptosis analysis showed that up-regulation of microRNA-340-5p could significantly inhibit the proliferation and induce apoptosis of Hep2 cells in vitro, and vice versa; Western Blot results showed that the levels of STAT3 and β-catenin, c-Myc, TCF-4, CyclinD1 and ROCK1 in Hep2 cells were significantly lower than those in the control group after over-expression of miR-340-5p, and vice versa. The expression of miR-340-5p is abnormally low in laryngeal cancer tissues and Hep2 cells. It can be used as a potential biological target for diagnosis and treatment of laryngeal cancer by targeting STAT3 gene to negatively regulate Wnt/β-catenin signaling pathway.

Effect of miR-340-5p targeting at BMP4 on differentiation of neural stem cells in rats / 中华行为医学与脑科学杂志

ObjectiveTo explore regulation effect of miR-340-5p on regulating bone morphogenetic protein 4(BMP4) expression and the differentiation of rat's NSCs.MethodsNSCs of rats were divided randomly into three groups: normal group (Mock),group with nonsense oligonucleotide (Anti-Con) and group with antisense oligonucleotide of miR-340-5p (Anti-miR-340-5p).The qRT-PCR was used to detect the relative expression of miR-340-5p.The expression of NF200 and MAP-2 was detected by immunocytochemical staining and immunofluorescence,respectively.Western blot was used to detect the expression of BMP4 protein.ResultsThe relative levels of miR-340-5p expression were significantly decreased in Anti-miR-340-5p group (0.14±0.01) compared with that of Mock group(1.01±0.17) and Anti-Con group(1.07±0.13) (P<0.01).Immunocytochemical staining indicated that NF200 was positive in cells of Anti-miR-340-5p group.The proportion of MAP2 positive cells was increased in Anti-miR-340-5p group compared with other groups (P<0.05).Western blot showed the increased expression of BMP4 protein in Anti-miR-340-5p group (0.84±0.09) compared with Mock group(0.53±0.04) and Anti-Con group (0.63±0.09) (P<0.05).ConclusionThe miR-340-5p may exert a potential function in regulating differentiation of NSCs into neurons through a negative regulation of BMP4.

MicroRNA-340-5p modulates cisplatin resistance by targeting LPAATβ in osteosarcoma

MicroRNAs (miRNAs) play an important role in drug resistance and modulate the efficiency of chemotherapy. A recent study indicated that miR-340 functions as a tumor suppressor in various types of cancer. However, the role of miR-340 in chemotherapy has not been reported yet. In this study, we found that miR-340 enhanced cisplatin (CDDP)-induced cell death. Induction of miR-340-5p expression decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells. Moreover, miR-340-5p decreased the accumulation of MRP1 and MDR1. We further explored the mechanism underlying the promoting effects of miR-340-5p on CDDP-induced cell death. We identified a potential target of miR-340 in the 3′ untranslated region of lysophosphatidic acid acyltransferase (LPAATβ) using the online program Targetscan (http://www.microrna.org). Luciferase reporter assays showed that miR-340 binds to the 3′UTR of LPAATβ. Enforced expression of miR-340-5p decreased the accumulation of LPAATβ in both MG-63 and Saos-2 cells. Silencing LPAATβ decreased the IC50 of CDDP and increased the apoptosis of CDDP-resistant MG-63 and Saos-2 cells, which is consistent with the effect of miR-340-5p on CDDP-induced cell death. Moreover, induced expression of LPAATβ compromised the effects of miR-340-5p on CDDP-induced cell death and accumulation of MRP1 and MDR1. Taken together, our data indicated that miR-340-5p enhanced the sensitivity to CDDP by targeting LPAATβ.

The effect of miR-340 on proliferation and apoptosis of breast cancer cell MDA-MB231 / 中国癌症杂志

Background and purpose:MicroRNA-340 (miR-340) has been demonstrated to play a role of negative regulation in many kinds of tumor, however, there are few reports about the relationship between miR-340 in proliferation and apoptosis of breast cancer cell. This study was aimed to explore the effect of miR-340 on proliferation and apoptosis of breast cancer cell MDA-MB231. Methods: The pre-miR-340 or anti-miR-340 were transiently transfected into breast cancer cell MDA-MB231 with LipofectamineTM2000. miR-340 level was detected by RT-PCR. The Western blot was performed to detect the protein level of cleaved-caspase-3. The inhibition rate of cell proliferation was evaluated by MTT assay. The cell apoptosis was studied by lfow cytometry. Results:The pre-miR-340 facilitated the expression of miR-340 in MDA-MB231 cells. The pre-miR-340 enhanced the protein level of cleaved-caspase-3, inhibited the proliferation of MDA-MB231 cells and increased its apoptosis. On the contrary, the expression of miR-340 was inhibited by anti-miR-340 in MDA-MB231 cells. The protein level of cleaved-caspase-3 was reduced after the anti-miR-340-transfected MDA-MB231 cells. Anti-miR-340 promoted the proliferation of MDA-MB231 cells. Decreased apoptosis of MDA-MB231 cells was observed by lfow cytometry. Conclusion:The overexpression of miR-340 can effectively inhibit the proliferation and increase the apoptosis of MDA-MB231 cells, which may be explained by up-regulating of protein cleaved-caspase-3 level.