Identification and validation of differential expression of miR-455-5p in plasma of children with Kawasaki disease / 中南大学学报(医学版)

OBJECTIVES@#To provide clues for further study of the relationship between miRNAs and Kawasaki disease (KD) development, and to provide molecular markers for ultimately improve the rate of early diagnosis for KD.@*METHODS@#We collected acute, recovery KD children's plasma and normal samples, then used the miRNAs Assay Chip to screen the differentially expressed miRNAs in the plasma from KD children. Subsequently, miR-455-5p, which had identified via miRNAs assay chip, was validated by quantitative real-time PCR via independent cohort.@*RESULTS@#According to the results of miRNAs Assay chip, we identified a miRNAs panel including 5 miRNAs significantly up-regulated and 5 miRNAs remarkably down-regulated in the plasma from KD children compared to the normal control; miR-455-5p in both of acute and recovery KD children's plasma was remarkably lower than that in the normal control (<0.001, =0.013, respectively), and miR-455-5p was also significantly lower than that in the recovery of KD children (=0.007) by independent cohort validation.@*CONCLUSIONS@#There are significantly differentially expressed circulating miRNAs between the KD children and normal control. We identified 10 miRNAs dysregulation in the KD children's plasma compared with the normal group. Circulating miR-455-5p in both of acute and recovery KD children's plasma is remarkably lower than that in the normal control, and miR-455-5p may considered as a marker to show the recovery process of KD children. Plasma specific circulating miRNAs play an important role in the early diagnosis of KD and become the new molecular marker of KD in the future.

Effect of miR-455-3p targeting HIPK2 on proliferation and apoptosis of osteoblasts induced by high glucose / 中国组织工程研究

BACKGROUND; Previous studies have shown that various miRNAs play a role in bone formation. miR-335-5p can protect osteoblasts from oxidative stress and protect osteoblasts under induction with ferric ammonium citrate, but the effect of miR-335-5p on osteoblast proliferation and apoptosis in high glucose environments is unknown. OBJECTIVE: To investigate the effect of miR-455-3p targeting HIPK2 on proliferation and apoptosis of osteoblasts induced by high glucose. METHODS; Dual luciferase reporter assay was used to verify the targeting of miR-455-3p to HIPK2. MC3T3-E1 cells were induced by high glucose in vitro, and MC3T3-E1 cells were treated as follows: Blank group, high glucose group, high glucose+miR-control group, high glucose+miR-455-3p group, high sugar+si-control group, high sugar+si-HIPK2 group, high glucose+miR-455-3p+pcDNA group and high glucose+miR-455-3p+pcDNA-HIPK2 group. The expression of miR-455-3p and HIPK2 mRNA was detected by qRT-PCR, cell viability was detected by MTT assay, apoptosis was detected by flow cytometry, and the expression of HIPK2, p-STAT3 and STAT3 protein was detected by western blot. RESULTS AND CONCLUSION: HIPK2 was a target gene of miR-455-3p, and miR-455-3p negatively regulated the expression of HIPK2. High glucose treatment inhibited the expression of miR-455-3p and promoted the expression of HIPK2. The over-expression of miR-455-3p or the inhibition of HIPK2 promoted MC3T3-E1 survival and inhibit cell apoptosis after high glucose treatment. The over-expression of HIPK2 partially reversed the survival promotion and apoptosis inhibition of miR-455-3p on osteoblasts induced by high glucose. miR-455-3p inhibited the expression of p-STAT3 in osteoblasts by regulating HIPK2. To conclude, miR-455-3p inhibits the apoptosis and promotes the proliferation of osteoblasts induced by high glucose via down-regulating HIPK2, which may be related to the inhibition of STAT3 signaling pathway.

miR-455-3p inhibits proliferation, migration and epithelial-mesenchymal transition of ovarian cancer SKOV-3 cells by regulating translipoprotein 4 / 中国肿瘤生物治疗杂志

@#Objective: To investigate the potential effects of miR-455-3p on proliferation, invasion and epithelial-mesenchymal transition (EMT) process of ovarian cancer cells, and explore its molecular mechanism. Methods: The IOSE80, SKOV-3 and A2780 cells were transfected with miR-455-3p mimics and negative controls (NC) by using LipofectamineTM 2000. Quantitative polymerase chain reaction (qPCR) assay was performed to detect the mRNA expressions of miR-455-3p and fatty acid-binding protein 4 (FABP4) in IOSE80, SKOV-3 and A2780 cells. The expression levels of FABP4 and EMT-associated proteins were detected by Wb. CCK-8 assay was applied to measure cell proliferation. Cell migration was analyzed by using Transwell assay. Bioinformatics analysis was used to predict the potential target of miR-455-3p, and the targeting effect of miR-455-3p on FABP4 was verified by the dual-luciferase reporter assay system. Results: The expression of miR-455-3p was declined (all P<0.05), while the expression of FABP4 was elevated (all P< 0.05) in ovarian cancer cells (SKOV-3 and A2780) in comparison with normal ovarian IOSE80 cells. Additionally, over-expression of miR-455-3p obviously inhibited cell proliferation and migration capacity of SKOV-3 cells (all P<0.05). Furthermore, over-expression of miR-455-3p impeded EMT progress by up-regulating E-cadherin expression and down-regulating N-cadherin and vimentin expression (all P<0.05). Importantly, the dual-luciferase reporter system, qPCR and Wb validated that FABP4 was a specific target gene of miR-455-3p, and miR-455-3p showed specific binding with FABP4 3’-UTR and negatively regulated the expression of FABP4 at both mRNA and protein levels. Mechanistically, over-expression of FABP4 apparently reversed the inhibitory effects of miR-455-3p on cell proliferation and migration of SKOV-3 cells (all P<0.05). Conclusion: miR-455-3p, acting as a tumor suppressor protein, can inhibit ovarian cancer cell proliferation, migration and EMT process by targeting FABP4, suggesting that miR-455-3p may be a new potential therapeutic target for ovarian cancer treatment.

MicroRNA-455 suppresses the oncogenic function of HDAC2 in human colorectal cancer

Colorectal cancer (CRC) is the fourth leading cause of cancer-induced mortality. Histone deacetylase 2 (HDAC2) is involved in prognosis and therapy of CRC. This study aimed to explore novel therapeutic targets for CRC. The alteration of HDAC2 expression in CRC tissues was estimated by qRT-PCR. After lentivirus transfection, HDAC2 knockdown was confirmed by western blot analysis. The effect of HDAC2 knockdown on cell proliferation was then assessed by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Screened by TargetScan, microRNA (miR)-455 was predicted to bind to 3′UTR of HDAC2 and the prediction was verified by luciferase assay. Finally, cells were transfected, respectively, with miR-455 mimics or miR-455 negative control (miR-NC) and the expression of HDAC2, cell proliferation and apoptosis of transfected cells were respectively evaluated by western blot analysis, MTT assay and flow cytometry. Results showed that the HDAC2 expression was up-regulated in CRC tissues (P<0.05). HDAC2 knockdown significantly decreased cell viability at day 3 (P<0.05), day 4 (P<0.01), and day 5 (P<0.001) after infection. Then, miR-455 was verified to directly target HDAC2, resulting in a significant difference in luciferase activity (P<0.01). Moreover, miR-455 decreased the expression of HDAC2 (P<0.01). miR-455 remarkably decreased cell viability at day 3 (P<0.05), day 4 (P<0.01), and day 5 (P<0.001) after transfection while inducing cell apoptosis (P<0.001). In conclusion, miR-455 inhibited cell proliferation while inducing cell apoptosis by targeting HDAC2 in CRC cells.