The role of lncRNA MSC-AS1/miR-29b-3p axis-mediated CDK14 modulation in pancreatic cancer proliferation and Gemcitabine-induced apoptosis

Pancreatic ductal adenocarcinoma (PDAC) remains a leading cause of cancer-related death due to the failure of traditional therapies. In the present study, we attempted to construct a lncRNA-miRNA-mRNA network which may modulate PDAC cell proliferation and Gemcitabine-induced cell apoptosis starting from CDK14, a new member of the CDK family and an oncogene in many cancers. Based on TCGA data, a significant positive correlation was observed between lncRNA MSC-AS1 and CDK14. Moreover, MSC-AS1 expression was upregulated in PDAC tissues. Higher MSC-AS1 expression was correlated with poorer prognosis in patients with PDAC. MSC-AS1 knockdown in Panc-1 and BxPC-3 cells significantly inhibited the cell proliferation. Moreover, miR-29b-3p, which has been reported to act as a tumor suppressor, was predicted to bind to both MSC-AS1 and CDK14. Contrary to MSC-AS1, higher miR-29b-3p expression was correlated to better prognosis in patients with PDAC. In both PDAC cell lines, miR-29b-3p negatively regulated MSC-AS1 and CDK14. As confirmed using luciferase reporter gene and RIP assays, MSC-AS1 served as a ceRNA for miR-29b-3p to counteract miR-29b-mediated CDK14 repression. MSC-AS1 knockdown inhibited CDK14 protein levels and PDAC proliferation and enhanced gemcitabine-induced cell death and apoptosis while miR-29b-3p inhibition exerted an opposing effect; the effect of MSC-AS1 knockdown was partially attenuated by miR-29b-3p inhibition. Taken together, we demonstrated that MSC-AS1/miR-29b-3p axis modulates the cell proliferation and GEM-induced cell apoptosis in PDAC cell lines through CDK14. We provided a novel experimental basis for PDAC treatment from the perspective of lncRNA-miRNA-mRNA network.     

Microarray-based measurement of microRNA-449c-5p levels in hepatocellular carcinoma and bioinformatic analysis of potential signaling pathways

The clinical role and potential molecular mechanisms of microRNA-449c-5p (miR-449c-5p) in hepatocellular carcinoma (HCC) tissues remains unclear. Combining multiple bioinformatic tools, we studied the miR-449c-5p expression levels in HCC tissues and explored possible target genes and related signaling pathways. First, miR-449c-5p expression data from microarrays provided by publicly available sources were mined and analyzed using various meta-analysis methods. Next, genes that were downregulated after miR-449c-5p mimic transfection into HCC cells were identified, and in silico methods were used to predict potential target genes. Several bioinformatic assessments were also performed to evaluate the possible signaling pathways of miR-449c-5p in HCC. Five microarrays were included in the current study, including GSE98269, GSE64632, GSE74618, GSE40744 and GSE57555. The standard mean difference was 0.44 (0.07–0.80), and the area under the curve was 0.68 (0.63–0.72), as assessed by meta-analyses, which consistently indicated the upregulation of miR-449c-5p in HCC tissues. A total of 2244 genes were downregulated after miR-449c-5p mimic transfection into an HCC cell line, while 5217 target genes were predicted by in silico methods. The overlap of these two gene pools led to a final group of 428 potential target genes of miR-449c-5p. These 428 potential target genes were primarily enriched in the homologous recombination pathway, which includes DNA Polymerase Delta 3 (POLD3). Data mining with Oncomine and the Human Protein Atlas showed a decreasing trend in POLD3 mRNA and protein levels in HCC tissue samples. This evidence suggests that miR-449c-5p could play an essential role in HCC through various pathways and that POLD3 could be a potential miR-449c-5p target. However, these in silico findings should be validated with further experiments.     

MiR-222 promotes the progression of polycystic ovary syndrome by targeting p27 Kip1

Polycystic ovary syndrome (PCOS) is one of the most complex and common reproductive and endocrinologic disorders in the child-bearing age of women. Recently, miR-222 were reported to be associated with the etiology of PCOS. However, the function of miR-222 during the pathogenesis of PCOS remains unclear. In the present study, we aimed to investigate the role of miR-222 in PCOS. Firstly, miR-222 expression was examined by quantitative real-time PCR (qRT-PCR) in PCOS. The effects of miR-222 on proliferation, apoptosis and cell cycle in KGN cells were analyzed by CCK-8 assay and flow cytometry analysis, respectively. In addition, bioinformatics analysis was used to predict the target genes of miR-222, and dual-luciferase reporter assay was applied to verified the interaction between miR-222 and p27 Kip1 in KGN cells. Moreover, the expressions of p27 Kip1 in KGN cells treated with miR-222 mimics or miR-222 inhibitor were evaluated by qRT-PCR and western blot assays. The results showed that the expression of miR-222 was remarkably upregulated in PCOS tissues compared with corresponding normal tissues. In the gain-of-function and loss-of-function assays, we revealed that miR-222 mimics significantly promoted cell proliferation, while miR-222 inhibitor induced cell apoptosis and cell cycle arrested. Furthermore, p27 Kip1 was identified as a target gene of miR-222, and could be negatively regulated by miR-222 mimics in KGN cells. In conclusion, our findings suggested that miR-222 may promote the progression of PCOS by targeting p27 Kip1.     

MicroRNA-214 promotes chronic kidney disease by disrupting mitochondrial oxidative phosphorylation

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miR-149与肿瘤关系的研究进展

miRNAs是一类长度约为20~25个核苷酸，参与基因调控表达的内源性非编码RNA。miR-149作为miRNAs的重要成员，在多种肿瘤中表达异常，其表达水平与肿瘤细胞增殖、转移、凋亡、耐药、患者的早期诊断及预后密切相关。因此，miR-149有望成为新一类抗肿瘤治疗的靶点。     

Sacituzumab govitecan: breakthrough targeted therapy for triple-negative breast cancer

Introduction: Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype associated with an increased risk of recurrence and cancer-related death. Unlike hormone receptor-positive or HER2-positive breast cancers, there are limited targeted therapies available to treat TNBC and cytotoxic chemotherapy remains the mainstay of treatment. Sacituzumab govitecan (IMMU-132) is an antibody-drug conjugate targeting Trop-2 expressing cells and selectively delivering SN-38, an active metabolite of irinotecan.

Areas covered: This review covers the mechanism of action, safety and efficacy of sacituzumab govitecan in patients with previously treated, metastatic TNBC. Additionally, efficacy data in other epithelial malignancies is included based on a PubMed search for ‘sacituzumab govitecan’ and ‘clinical trial’.

Expert opinion: Sacituzumab govitecan has promising anti-cancer activity in patients with metastatic TNBC previously treated with at least two prior lines of systemic therapy based on a single arm Phase I/II clinical trial. A confirmatory Phase III randomized clinical trial is ongoing. Sacituzumab govitecan has a manageable side effect profile, with the most common adverse events being nausea, neutropenia, and diarrhea. The activity of sacituzumab govitecan likely extends beyond TNBC with promising early efficacy data in many other epithelial cancers, including hormone receptor-positive breast cancer.     

中缝核miR-16与5-羟色胺转运体在失眠模型大鼠中的表达

目的研究中缝核miR-16以及5-羟色胺转运体(serotonin transporter,SERT)的表达在失眠症发病机制中的作用。方法 20只雌性SD大鼠,随机分成对照组和失眠组。失眠组大鼠接受腹腔注射对氯苯丙氨酸(pchlorophenalanine,PCPA)350 mg/(kg·d),连续3 d,对照组给予等量生理盐水。取中缝核组织,测定其miR-16、SERT m RNA与SERT蛋白水平,进行注射前后的组间比较。结果失眠组大鼠中缝核miR-16相对水平(1.23±0.33)与对照组(0.71±0.25)比较明显升高,差异具有统计学意义(t=6.68,P=0.000);而失眠组SERT mRNA相对水平(0.68±0.14)以及SERT蛋白相对水平(0.28±0.11)显著低于相应的对照组(1.06±0.30,0.57±0.15)(t=3.94,P=0.004;t=4.69,P=0.002)。结论中缝核miR-16以及SERT的异常表达,可能参与了失眠症的发病机制。     

miR-194靶向EZH2抑制甲状腺癌细胞增殖、迁移和侵袭

目的:研究miR-194、EZH2对甲状腺癌细胞增殖、迁移和侵袭的影响，并探讨其作用机制。方法:采用qRT-PCR法检测甲状腺癌组织、癌旁正常组织及甲状腺癌细胞和正常甲状腺上皮细胞中miR-194和EZH2的mRNA表达；将miR-194（转染miR-194 mimics）、miR-NC（未转染细胞）、inhibitor-NC（转染空inhibitor）、miR-194 inhibitor（转染miR-194 inhibitor）、si-EZH2（转染si-EZH2）、miR-194+Vector（miR-194 mimics和pcDNA 3.1共转染）、miR-194+EZH2（miR-194 mimics和pcDNA 3.1-EZH2共转染）均以脂质体法转染到SW579、IHH-4细胞；Western blot检测细胞中EZH2的蛋白表达；MTT法检测细胞的增殖；Transwell检测细胞的迁移和侵袭；双荧光素酶报告基因检测实验检测细胞荧光素酶活性。结果:与正常组相比，甲状腺癌组EZH2的表达显著升高，miR-194的表达显著降低；与人正常甲状腺上皮细胞相比，甲状腺癌细胞中EZH2表达显著升高，miR-194的表达显著降低，且过表达miR-194和沉默EZH2均可抑制甲状腺癌细胞增殖、迁移和侵袭。EZH2为miR-194的靶标，且EZH2可逆转过表达miR-194对甲状腺癌细胞增殖、迁移和侵袭的抑制作用。结论:miR-194可抑制甲状腺癌细胞的增殖、迁移和侵袭，可能与靶向EZH2有关，将可为miR-194靶向治疗甲状腺癌提供依据。     

miR-26b通过调节Notch1信号通路参与原发性肝细胞肝癌侵袭的机制研究

目的:探讨miR-26b参与原发性肝细胞肝癌（HCC）侵袭的机制。方法:在细胞培养液中培养人肝细胞系HL-7702和HCC细胞各系Hepb-3、HuH-7、MHCC97-L、MHCC97-H。实时荧光定量PCR法（qRT-PCR）检测miR-26b的表达水平；用miR-26b mimics、miR-26b inhibitors和Notch1-siRNA分别转染HCC细胞；MTT实验检测转染后HCC细胞的活力；采用Western blot检测Notch1受体蛋白表达水平的变化；Transwell小室测定不同处理后的HCC细胞的侵袭能力。结果:人正常肝细胞系HL-7702和HCC细胞系Hepb-3、HuH-7、MHCC97-L、MHCC97-H中的miR-26b相对表达含量随其侵袭和迁移能力的升高而依次下降；抑制miR-26b的表达，Notch1受体蛋白表达明显增高，而此时HCC细胞的侵袭性显著增强；相反，上调miR-26b的表达，Notch1受体蛋白表达明显降低，而HCC细胞侵袭性显著下降；miR-26b可能通过调控Notch1信号通路调节HCC细胞侵袭性。结论:miR-26b通过负调控Notch1信号通路抑制HCC细胞侵袭能力，为HCC侵袭的机制奠定了理论基础，miR-26b可能成为HCC治疗的新靶点。