Effect of fenofibrate on the expression of miR-26a-5p/PTEN in retinal neurons of diabetic mice / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To study the protective effect of fenofibrate on diabetic retinal neurodegeneration and observe its effect on miR-26a-5p and its target gene PTEN in the retinal of diabetic mice.METHODS: Diabetic mice models were established and they were gavaged by fenofibrate. H& E staining and transmission electron microscopy were used to observe the impairments of retinal neurons. Real-time PCR was used to examine the expression of miR-26a-5p, and Western blotting was employed to measure the expression of phosphatase and tensin homologue(PTEN)in the retina of diabetic mice. The expression level of nuclear factor-κB(NF-κB), interleukin-1β(IL-1β)and the morphology of neural tissues were observed.RESULTS: When compared with the diabetic mice, fenofibrate significantly attenuated the damage to retinal ganglion cells and the atrophy of retinal nerve fiber layer. While the level of miR-26a-5p was increased and the levels of PTEN and inflammatory mediators were significantly decreased in the retina of fenofibrate treated diabetic mice, with significant statistical significance(P<0.05).CONCLUSIONS: Fenofibrate protects against diabetic retinal neurodegeneration by upregulating miR-26a-5p and inhibiting PTEN, attenuating the inflammatory response and alleviating retinal cell injury.

Mechanism of miR-26a-5p/cAMP response element binding protein 1 molecular axis regulating osteogenic differentiation of adipose-derived mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1).@*METHODS@#The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture.@*RESULTS@#The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05).@*CONCLUSION@#Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.

Experimental study of miR-26a regulating CTGF expression in radiation-induced heart disease / 中华放射肿瘤学杂志

Objective:To investigate the regulatory effect of miR-26a in radiation-induced heart disease (RIHD) mice.Methods:C57/BL6 mice were used to establish RIHD models. The cardiac function, fibrosis, the expression levels of collagen 1 (COL1) and connective tissue growth factor (CTGF), and miR-26a were detected in RIHD mice. Whether CTGF was the target gene of miR-26a was verified by dual luciferase kit. Moreover, cardiac fibroblasts were transfected with miR-26a up and miR-26a down lentivirus vectors to construct the miR-26a overexpression and underexpression cell models. The expression of CTGF, proliferation, and apoptosis of cardiac fibroblasts were detected.Results:In the RIHD mice, heart function was decreased, myocardial fibrosis was remodeled, the expression levels of COL1 and CTGF were up-regulated, and the expression level of miR-26a was down-regulated. Dual luciferase reporter assay confirmed that CTGF was the target gene regulated by miR-26a. Overexpression of miR-26a could inhibit the expression of CTGF, suppress the proliferation of cardiac fibroblasts, promote cell apoptosis and secrete collagen. Underexpression of miR-26a yielded the opposite results.Conclusion:MiR-26a affects the function of cardiac fibroblasts by targeting CTGF and probably mediates the process of radiation-induced myocardial fibrosis, which may become a new regulatory target of RIHD.

Effects of microRNA-26a targeted high-mobility group A2 protein antibody on the proliferation and migration of hepatoma cells / 中国基层医药

Objective:To investigate the effects of miRNA-26a (miR-26a) on the target gene HMGA2 on the proliferation and migration of hepatoma cells and the underlying mechanism. Methods:Liver cancer tissue samples ( n = 30) and adjacent normal tissue samples ( n = 30) pathologically confirmed by Wenzhou Hospital of Traditional Chinese Medicine between September 2018 and September 2019 were collected. MiR-26a mimics, control mimics (miR-Control), high-mobility group A2 protein (HMGA2) siRNA or negative control siRNA (Control) were transfected into human hepatoma cell lines HepG2 or Huh-7 cells. The expression of miR-26a in hepatocellular carcinoma tissue was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). MTT assay and scratch test were performed to determine the ability of cell proliferation and migration. RT-qPCR and western blotting were performed to detect miR-26a and HMGA2 mRNA expression. The relationship between miR-26a and HMGA2 mRNA was analyzed using Bioinformatics and luciferase reporter gene assay. Results:RT-qPCR results showed that the expression level of miR-26a in hepatocellular carcinoma tissue was 0.11 ± 0.02, which was significantly lower than that in normal tissues (0.25 ± 0.03, t = 21.268, P < 0.05). The expression level of miR-26a in stage III + IV was 0.05 ± 0.01, which was significantly lower than that in stage I + II (0.09 ± 0.01, t = 15.491, P < 0.05). Cell experiment showed that in the miR-26a group, the proliferation ability of Huh-7 cells was (3.10 ± 0.30) and (4.10 ± 0.40), and the proliferation ability of HepG2 cells was (3.08 ± 0.31) and (4.11 ± 0.40), which was significantly lower than that in the control group [(3.90 ± 0.40), (5.50 ± 0.60), (3.92 ± 0.41), (5.49 ± 0.58), t = 8.764, 10.634, 11.148, 10.728, all P < 0.05]. In the miR-26a group, the migration ability was (0.50 ± 0.06), (0.65 ± 0.07), which was significantly lower than that in the control group [(1.00 ± 0.10), (0.96 ± 0.10), t = 23.483, 13.910, both P < 0.05]. Bioinformatics and in vitro experiments showed that HMGA2 was a direct target of miR-26a. Restoring the expression of HMGA2 in miR-26a mimics-transfected cells, compared with that in the miR-26a group [(0.24 ± 0.02), (0.31 ± 0.03);(0.45 ± 0.05)], could significantly reverse the inhibitory effect of miR-26a on tumor cell proliferation and migration [(0.31 ± 0.03), (0.40 ± 0.04);(0.93 ± 0.08), t = 10.634, 9.859, 27.868, all P < 0.05). Conclusion:miR-26a inhibits the proliferation and migration of hepatoma cells by directly targeting HMGA2. The abnormal decrease of miR-26a and the increase of HMGA2 may be the important factors that participate in the occurrence and development of liver cancer.

Role and action mechanism of microRNA-26a targeting EZH2 in ultraviolet A-induced photoaging of human skin fibroblasts / 中华皮肤科杂志

Objective:To investigate the expression of microRNA (miR) -26a in human skin fibroblasts during photoaging induced by ultraviolet A (UVA) , and to evaluate the effect of up-or down-regulation of miR-26a expression on the methylation level of the whole genome, the target gene enhancer of zeste homolog 2 (EZH2) and cell aging.Methods:Some human skin fibroblasts were irradiated with 10 J/cm 2 UVA once a day for 7 consecutive days, RNA was extracted on days 0, 3 and 7, and real-time quantitative reverse PCR (RT-PCR) was performed to determine the expression of miR-26a; miR-26a mimics and inhibitors were transfected into fibroblasts to up-or down-regulate the expression of miR-26a respectively, and fluorescence microscopy and RT-PCR were performed to determine the expression of miR-26a and evaluate the transfection efficiency. Some human skin fibroblasts were divided into 6 groups: blank control group receiving no treatment, UVA group treated with UVA irradiation according to the above method, miR-26a mimic group transfected with miR-26a-mimics, UVA+miR-26a mimic group transfected with miR-26a-mimics followed by UVA irradiation, miR-26a inhibitor group transfected with miR-26a inhibitors, UVA+miR-26a inhibitor group transfected with miR-26a inhibitors followed by UVA irradiation. On day 7, cells in each group were collected after the end of UVA irradiation. Then, flow cytometry was performed to detect cell cycle, DNA methylation quantitative detection kit was used to detect the methylation level of whole genome, RT-PCR was conducted to determine the mRNA expression of EZH2 (a histone-lysine N-methyltransferase enzyme) , DNA methyltransferase 1 (DNMT1) and miR-26a, and Western blot analysis was performed to determine the protein expression of EZH2 and DNMT1. Statistical analysis was carried out by using one-way analysis of variance and least significant difference- t test. Results:Compared with the unirradiated control group, the expression of miR-26a gradually increased in the UVA irradiation group over time during the culture, and there was a significant difference in the expression of miR-26a between the two groups after 7 days of UVA irradiation ( t=5.295, P < 0.05) . Strong fluorescence signals were observed in the miR-26a mimic-or miR-26a inhibitor-transfected fibroblasts, suggesting a high transfection efficiency. Flow cytometry showed that the proportion of cells at G1 phase significantly differed among the blank control group, UVA group, miR-26a mimic group, UVA+miR-26a mimic group, miR-26a inhibitor group, and UVA+miR-26a inhibitor group (52.82% ± 2.56%, 78.56% ± 4.34%, 53.63% ± 3.13%, 89.52% ± 4.17%, 54.39% ± 3.86%, 65.34% ± 4.78%, respectively; F=46.728, P < 0.01) , and significantly higher in the UVA group than in the blank control group ( t=8.848, P < 0.01) , higher in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group ( t=11.922, 3.154, P < 0.01, < 0.05, respectively) , and higher in the UVA+miR-26a inhibitor group than in the miR-26a-inhibitor group ( t=3.087, P < 0.05) , but significantly lower in the UVA+miR-26a inhibitor group than in the UVA group ( t=3.547, P < 0.05) . Detection of the genome-wide methylation level showed that the methylation level ( A450 value) significantly differed among the above groups (0.676 ± 0.024, 0.323 ± 0.043, 0.506 ± 0.035, 0.169 ± 0.024, 0.602 ± 0.036, 0.422 ± 0.029, respectively, F=97.402, P < 0.01) , and significantly lower in the UVA group than in the blank control group ( P < 0.01) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.01) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.01) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . RT-PCR and Western blot analysis showed significant differences in the mRNA and protein expression of EZH2 and DNMT1 respectively among the 6 groups (both P < 0.05) , which were significantly lower in the UVA group than in the blank control group ( P < 0.05) , lower in the UVA+miR-26a mimic group than in the miR-26a mimic group and UVA group (both P < 0.05) , and lower in the UVA+miR-26a inhibitor group than in the miR-26a inhibitor group ( P < 0.05) , but significantly higher in the UVA+miR-26a inhibitor group than in the UVA group ( P < 0.05) . Conclusion:In the UVA irradiation-induced photoaging of skin fibroblasts, miR-26a expression was up-regulated, cellular proliferative activity and genome-wide methylation level decreased; up-regulation of miR-26a expression could down-regulate the expression of its target gene EZH2 and methylation-related gene DNM1, and promote cell photoaging, while down-regulation of miR-26a expression could up-regulate the expression of EZH2 and DNMT1, and inhibit cell photoaging.

Expression of lncRNA FAM95B1 in glioma and the possible mechanism of its effect on the proliferation and migration of LN382 cells / 中国肿瘤生物治疗杂志

@#[摘 要] 目的：探讨lncRNA FAM95B1对胶质瘤细胞增殖和迁移能力的影响并探究其相关作用机制。方法： 选取2018年1月至2020年8月于合肥市第三人民医院行手术治疗的38例胶质瘤患者的胶质瘤组织及癌旁组织标本，利用qPCR检测胶质瘤组织与4种细胞系中FAM95B1的表达水平，以表达最低的胶质瘤LN382细胞为研究对象，转染空载质粒（对照组）或pcDNA3.1-FAM95B1质粒（实验组）。MTT法和划痕实验检测FAM95B1对LN382细胞增殖和迁移能力的影响。生物信息学分析技术和双荧光素酶基因报告实验预测并验证FAM95B1与miR-26a-5p及PTEN之间的相互作用机制，应用qPCR和WB法检测FAM95B1对miR-26a-5p和PTEN表达的影响。结果： FAM95B1在胶质瘤组织中的表达明显低于癌旁组织（P<0.01）。FAM95B1在多种胶质瘤细胞系中的表达均明显低于正常脑胶质细胞（均P<0.01）。过表达FAM95B1可以下调LN382细胞的增殖（P<0.05）和迁移能力（P<0.01）。FAM95B1能够靶向结合miR-26a-5p（P<0.01），miR-26a-5p能够靶向结合PTEN mRNA（P<0.01）。过表达FAM95B1可下调LN382细胞中miR-26a-5p的表达（P<0.01），促进PTEN mRNA的表达（P<0.01）。结论：在胶质瘤组织和细胞系中异常低表达的FAM95B1通过发挥竞争性内源RNA的功能抑制miR-26a-5p的表达而增强PTEN蛋白表达，抑制胶质瘤细胞系LN382的增殖和迁移。

miR-26a-5p protects against myocardial ischemia/reperfusion injury by regulating the PTEN/PI3K/AKT signaling pathway

Reperfusion strategies in acute myocardial infarction (AMI) can cause a series of additional clinical damage, defined as myocardial ischemia/reperfusion (I/R) injury, and thus there is a need for effective therapeutic methods to attenuate I/R injury. miR-26a-5p has been proven to be an essential regulator for biological processes in different cell types. Nevertheless, the role of miR-26a-5p in myocardial I/R injury has not yet been reported. We established an I/R injury model in vitro and in vivo. In vitro, we used cardiomyocytes to simulate I/R injury using hypoxia/reoxygenation (H/R) assay. In vivo, we used C57BL/6 mice to construct I/R injury model. The infarct area was examined by TTC staining. The level of miR-26a-5p and PTEN was determined by bioinformatics methods, qRT-PCR, and western blot. In addition, the viability and apoptosis of cardiomyocytes were separately detected by MTT and flow cytometry. The targeting relationship between miR-26a-5p and PTEN was analyzed by the TargetScan website and luciferase reporter assay. I/R and H/R treatment induced myocardial tissue injury and cardiomyocyte apoptosis, respectively. The results showed that miR-26a-5p was down-regulated in myocardial I/R injury. PTEN was found to be a direct target of miR-26a-5p. Furthermore, miR-26a-5p effectively improved viability and inhibited apoptosis in cardiomyocytes upon I/R injury by inhibiting PTEN expression to activate the PI3K/AKT signaling pathway. miR-26a-5p could protect cardiomyocytes against I/R injury by regulating the PTEN/PI3K/AKT pathway, which offers a potential approach for myocardial I/R injury treatment.

Resveratrol protects human retinal pigment epithelial cells from toxicity of high glucose by up-regulation of miR-26a / 中国临床药理学与治疗学

AIM: To study the protective effects and mechanism of resveratrol (RES) on the injury of human retinal pigment epithelial cells (ARPE-19) induced by high glucose (HG). METHODS: ARPE-19 cells were cultured in HG to simulate injury. Cell viability, apoptosis, ROS generation and miR-26a level were examined by CCK-8 assay, flow cytometry assay, DCFH-DA staining and RT-qPCR, respectively. Expression of proteins associated with viability, apoptosis and oxidative stress was measured by Western blot analysis. In addition, the involvements of the ERK and Wnt/β-catenin pathways were analyzed by Western blot analysis.RESULTS:HG reduced cell viability while promoted apoptosis and oxidative stress in ARPE-19 cells. RES ameliorated HG-induced cell injury. The expression of miR-26a was up-regulated by RES in HG-treated cells, and miR-26a inhibition obviously reversed the effects of RES on HG-treated cells. Finally, we found the ERK and Wnt/β-catenin pathways were inhibited by RES through up-regulation of miR-26a. CONCLUSION: RES protected ARPE-19 cells against HG-induced injury through up-regulating miR-26a, along with inhibition of the ERK and Wnt/β-catenin pathways. RES might be a potential therapeutic drug for diabetic retinopathy.

Effects of miR-26a targeting HMGA1 gene on growth, invasion and migration of colon cancer cells / 吉林大学学报(医学版)

Objective: To investigate the effects of miR-26a targeting high mobility group protein 1 (HMGA1) gene on the growth, invasion and migration of colon cancer cells, and to clarify whether the HMGA1 gene was the target gene of miR-26a. Methods: The miR-NC (miR-NC group), miR-26a mimics (miR-26a mimics group) and miR-26a inhibitor (miR-26a inhibitor group) were transfected into the human colon cancer SW480 cells. RT-PCR and Western blotting methods were used to detect the mRNA and protein expression levels of HMGA1. Luciferase reporter gene detection kit was used to detect the double luciferase activity in SW480 cells and to determine whether HMGA1 was the target gene of miR-26a. The cell proliferation activities of cells in various groups were detected by CCK8 assay; the number of invasion and migration cells was detected by Transwell chamber method. Results: HMGA1 gene was the target gene of miR-26a. Compared with miR-NC group, the proliferation activities of colon cancer SW480 cells in miR-26a mimics group at after 24, 48 and 72 h after transfection were significantly decreased (P<0. 01), while the proliferation activities of colon cancer SW480 cells in miR-26a inhibitor group were significantly increased (P<0. 01). Compared with miR-NC group, the proliferation activities of colon cancer SW480 cells, the number of invasion and migration cells in miR-26a mimics group and miR-26a mimics + pcDNA3. 1-HMGA1 group at different time points were significantly decreased (P<0. 01); the proliferation activities of colon cancer SW480 cells, the number of invasion and migration cells in miR-NC + pcDNA3. 1-HMGA1 group were increased (P<0. 01). Compared with miR-26a mimics group, the proliferation activities of colon cancer SW480 cells, the number of invasion and migration cells in miR-26a mimics+ pcDNA3. 1-HMGA1 group at different time points were increased (P<0. 01); compared with miR-NC+pcDNA3. 1-HMGA1 group, the proliferation activities of colon cancer SW480 cells, the number of invasion and migration cells in miR-26 mimics + pcDNA3. 1-HMGA1 group at different time points were decreased (P<0. 01). Conclusion: HMGA1 gene is the target gene of miR-26a. Up-regulation of the expression of miR-26a can inhibit the proliferation of colon cancer SW480 cells and downregulation of the expression of miR-26a can promote the proliferation of colon cancer SW480 cells.

Effects of miR-26a on proliferation, apoptosis, migration and invasion of uveal melanoma cell and its mechanism / 眼科新进展

Objective To analyze the effects of miR-26a on proliferation,apoptosis,migration and invasion of uveal melanoma cell.Methods The expressions level of miR-26a in the uveal melanoma cell lines SP6.5 and M23 and normal cell line ARPE-19 was detected by qRT-PCR.The SP6.5 cell line was divided into miR-26a mimics group (transfect with miR-26a mimics) and NC group (transfect with scramble by Lipofectamine 2000).The proliferation and apoptosis ability were measured by CCK-8 assay and flow cytometry.The cell wound scratch assay and transwell assay were used to detect the migration and invasion ability.The expression level of enhancer of zeste homolog 2 (EZH2) protein was measured by Western blot.Results The expressions level of miR-26a in uveal melanoma cell line SP6.5 was 0.250 ± 0.029,M23 was 0.350 ±0.017,which was significantly lower than 1.0 in normal cell line ARPE-19 (all P ＜0.001).The OD450 value at 72 hours,96 hours and 120 hours in miR-26a mimics group (0.69 ±--0.09,1.23 ± 0.15,2.12 ± 0.23) were significantly lower than those in NC group (1.39-0.11,2.35 ±0.25,3.53 ±0.27) (all P ＜0.05).The apoptosis rate of miR-26a mimics group (15.60％ ± 2.30％) was significantly higher than that of NC group (5.00％ ± 0.70％) (P ＜ 0.01).The wound healing rate of miR-26a mimics group (23.7％ ±2.1％) was significantly lower than that of NC group (68.9 ±5.1％) (P ＜0.01).While the invasive cell number (45.1 ± 3.9) was also significantly less than NC group (115.3 ± 8.9) (P ＜ 0.01).The expression level of EZH2 protein in miR-26a mimics group (0.39 ±0.09) was significantly lower than that of NC group (1.0,P ＜0.01).Conclusion MiR-26a is low expressed in uveal melanoma cells.Over expression of miR-26a inhibit the proliferation,migration and invasion of uveal melanoma cell,and promote the apoptosis,which may be associated with down-regulated expression of EZH2.

Expression and diagnostic value of serum miR-26a/b in patients with gastric cancer / 中国肿瘤临床

Objective:To discuss the diagnostic value of miR-26a/b and relationship of this microRNA with clinicopathological features in patients with gastric cancer. Methods:The expression of serum miR-26a/b was detected in 121 patients with gastric cancer and 116 healthy controls using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). The relationship of miR-26a/b and clinicopathological parameters of patients were analyzed. The receiver operating curve (ROC) was constructed to in vestigate the value of miR-26a/b in the diagnosis of gastric cancer. Results:The relative expression levels of serum miR-26a and miR-26b in patients with gastric cancer were lower than those in the control group (1.60±1.02 vs. 5.35±0.44;1.44±0.71 vs. 5.35±0.71;P<0.05). The relative expression level of miR-26a/b correlated with TNM stage, and the relative expression level of miR-26a also correlated with invasion depth and lymph node metastasis (P<0.05), but not with sex, age, tumor size, or histological type (P>0.05). The area under the ROC curve of miR-26a was 0.828 (95％CI:0.776～0.881), with sensitivity of 73.3％and specificity of 81.0％, while the area under the ROC curve of miR-26b was 0.853 (95％CI:0. 801～0.906), with sensitivity of 68.1％and specificity of 99.2％. Conclusion:The expression of miR-26a/b significantly reduced in patients with gastric cancer, and its expression level correlated with the clinical stage, invasion depth, and lymph node metastasis. MiR-26a/b has potential diagnostic value for gastric cancer.

MicroRNA-26a inhibits cell migration and invasion in cervical cancer through targeting high mobility group protein A1(HMGA1) / 中华微生物学和免疫学杂志

Objective To investigate the role of microRNA-26a (miR-26a) in cell migration and invasion in cervical cancer and its regulatory effects on high mobility group protein A1(HMGA1). Methods Both HeLa and SiHa cells were divided into four groups:miR-26a mimic group,mimic control group,miR-26a inhibitor group and inhibitor control group. MiR-26a expression was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Target genes for miR-26a-5p were predicted by bioinformatics and verified by dual-luciferase reporting system. HMGA1 expression was evaluated by Western blot and qRT-PCR. Cell migration and invasion were analyzed by in vitro assays. Results (1) HMGA1 was predicted as one of the potential targets of miR-26a by TargetScan. Results of dual-luciferase activity assay further con-firmed that HMGA1 was directly regulated by miR-26a. (2) Expression of miR-26a and HMGA1 at mRNA level was respectively enhanced and inhibited in miR-26a mimic-transfected HeLa as well as SiHa cells as compared with those in the corresponding mimic control groups (P<0.05). On the contrary, expression of miR-26a and HMGA1 at mRNA level was respectively reduced and increased in miR-26a inhibitor groups as compared with those in the corresponding inhibitor control groups(P<0.05). (3) Expression of HMGA1 in miR-26a mimic-transfected HeLa and SiHa cells was lower than that in the corresponding mimic control groups(P<0.05). But expression of HMGA1 in miR-26a inhibitor groups was higher than that in the corre-sponding inhibitor control groups(P<0.05). (4) Abilities of cell migration and invasion were suppressed in miR-26a mimic groups as compared with those in the corresponding mimic control groups,but were enhanced in miR-26a inhibitor groups as compared with those in the corresponding inhibitor control groups(P<0.05). Conclusion MiR-26a can inhibit the proliferation and invasion of HeLa and SiHa cells through targeting HMGA1,suggesting that miR-26a is closely related to cervical cancer and might be associated with chemo-therapy resistance in cervical cancer. This study might provide a new strategy for the prevention and treat-ment of cervical cancer.

Progress in function of microRNA during lung development / 国际儿科学杂志

MicroRNAs are composed of a large group of small, non-coding RNA sequences that are highly conserved among species.So far, researchers have uncovered that microRNAs play important roles in various biological processes including developmental timing, cell fate determination, immune responses, insulin secretion, and progression of various cancers.Recently, microRNAs have become a major focus of interest for research in lung development.This article provides an overview of the various microRNAs that have been implicated in lung organogenesis.

miR-26a suppresses gastric cancer cell invasion by targeting MMP16 / 中国癌症杂志

Background and purpose:Invasion and metastasis lead to poor prognosis in gastric cancer. In this study, we investigated the potential function of miR-26a in gastric cancer.Methods:Real-time lfuorescent quantitative polymerase chain reaction (RTFQ-PCR) was used to detect the expression of miR-26a in gastric cancer cells.In vitro CCK-8 assay, cloning formation assay and Matrigel-Transwell assay were used to evaluate the proliferation, migration and invasion of gastric cancer cells. A luciferase reporter assay was also conducted to confirm that matrix metallo-proteinase-16 (MMP16) is a direct target of miR-26a.Results:miR-26a was down-regulated in gastric cancer tissues compared with that in non-cancerous tissues. Functional studies showed that miR-26a inhibited cell proliferation, col-ony formation, cell motility and invasion. However, miR-26a had no effect on cell proliferation. We also characterized MMP16 as a direct target of miR-26a. We showed that knocking down MMP16 in gastric cancer cells signiifcantly de-creased MMP16 expression and inhibited cell invasion, whereas ectopic MMP16 expression signiifcantly abrogated the suppressed cell invasion induced by miR-26a.Conclusion:miR-26a suppresses gastric cancer cell invasion by targeting MMP16. miR-26a could represent a potential therapeutic target for gastric cancer.

Hypoxia promotes apoptosis of neural stem cells and down-regulates miR-26 a / 中国病理生理杂志

AIM: To investigate the effect of cobalt chloride (CoCl2) on the apoptosis of neural stem cells (NSCs) and the expression of microRNA-26a (miR-26a) in vitro, and to explore the mechanisms of NSC apoptosis in-duced by CoCl 2 .METHODS:NSCs were exposed to CoCl 2 at different doses (200~600μmol/L) for 24 h.The cell via-bility and apoptosis were measured by CCK-8 assay and TUNEL method.The expression of miR-26a-3p, miR-26a-5p, GSK-3β, caspase-3, Bcl-2 and Bax was examined by real-time PCR.The protein levels of Bcl-2 and Bax were detected by Western blotting .RESULTS: The cell viability was inhibited and the apoptosis of NSCs was increased significantly by CoCl2 in a dose-dependent manner (P<0.05).CoCl2 at concentration of 400μmol/L for 24 h was used to induce apopto-sis and the expression of miR-26a was down-regulated compared with control (P<0.05).Exposure to CoCl2 at concentra-tion of 400μmol/L up-regulated the expression of GSK-3β, caspase-3 and Bax , down-regulated the expression of Bcl-2 and Bcl-2/Bax (P<0.05).CONCLUSION:CoCl2 at concentration of 400μmol/L induces the apoptosis of NSCs obviously . CoCl2 may induce the NSC apoptosis by mitochondrial apoptotic pathway .Declining miR-26a may be related to NSC apopto-sis.

IL-6 upregulation contributes to the reduction of miR-26a expression in hepatocellular carcinoma cells

A recent study showed that miR-26a is downregulated in hepatocellular carcinoma tissues and that this downregulation is an independent predictor of survival. Interestingly, the same study also reported that miR-26a downregulation causes a concomitant elevation of IL-6 expression. Because miR-26a expression was found to be transcriptionally downregulated by oncogene c-Myc in various cancers, and the expression of c-Myc was increased by IL-6 stimulation, we hypothesized that IL-6 contributes to reduction of miR-26a in hepatocellular carcinoma. Serum IL-6 was measured by ELISA and miR-26a was detected by qRT-PCR. The data of 30 patients with hepatocellular carcinoma who had undergone surgical tumor resection revealed that serum IL-6 could be considered to be a predictor of survival up to 5 years for hepatocellular carcinoma patients (log-rank test, P < 0.05). We observed that the serum IL-6 concentration was inversely correlated with miR-26a expression in cancerous tissues (Pearson correlation test, r = -0.651, P < 0.01). Furthermore, by in vitro experiments with HepG2 cells, we showed that IL-6 stimulation can lead to miR-26a suppression via c-Myc activation, whereas in normal hepatocyte LO2 cells incubation with IL-6 had no significant effect on miR-26a expression. Taken together, these results indicate that miR-26a reduction in hepatocellular carcinoma might be due to IL-6 upregulation.

Prediction of hsa-miR-26a target genes and application in lung development / 中华实用儿科临床杂志

Objective The bioinformatics software and database were involved in prediction of the target genes of hsa-miR-26a,so as to lay foundation and provide theoretical basis for the further studies of hsa-miR-26a biological function in fetal lung development.Methods All literature of miR-26a were searched in PubMed and Google ; miRBase database was used to obtain the sequence of hsa-miR-26a and to analyze its conservation.The target genes of miR-26a were predicted using miRNA target gene database miRGen2.0.TargetScans and PicTar were used to predict target genes of hsa-miR-26a.The intersection of the 2 results and validated targets from DIANA LAB-TarBase 6.0 datebase was analyzed by gene ontology and pathway analysis.Results Hsa-miR-26a had been reported in cancer,cell differentiation,organ development,the immune system as well as involved in other biological process;hsa-miR-26a was highly conservative among different species.The functions of these target genes were enriched in translation regulation,the protein modification,the regulation of celluar proliferation,apoptosis and differentiation process,kinase activity regulation,target genes exist in all of the cell components,including cell membrane,cytoplasm and nucleus.The Wnt signaling pathway,mitogen-activated protein kinase signaling pathway,transforming growth factor-β signaling pathway,the pathway of tumor p53 signaling pathways,cell cycle and adherens junction pathways were significantly enriched and prostate cancer,small cell lung cancer,colorectal cancer,renal cell cancer and glioma were mainly involved (all P ＜ 0.05).Conclusions The target genes of hsa-miR-26a are enriched in multiple biological process.The prediction and bioinformatic analysis of miR-26a target genes lay the foundation for the further study in fetal lung development.