The miR-124 regulates the expression of BACE1/β-secretase correlated with cell death in Alzheimer's disease

The role of miR-124 on the expression of β-site APP cleaving enzyme 1 (BACE1), an important cleavager of amyloid precursor protein that plays a pivotal role in the β-amyloid production, was studied in this paper using cellular models for Alzheimer’ disease (AD) of cultured PC12 cell lines and primary cultured hippocampal neurons. The aim of the present study was to uncover novel potential miR-124 targets and shed light on its function in the cellular AD model. MiR-124 expression was steadily altered when its mimic and inhibitor were transfected in vitro. The results showed the expression of BACE1, one of the potential functional downstream targets of miR-124, was well correlated with cell death induced by Aβ neurotoxicity, and its expression level could be up- and down-regulated by suppression or over expression of miR-124 level respectively. These findings suggest that miR-124 may work as a basilic regulating factor to alleviate cell death in the process of AD by targeting BACE1, play an essential role in the control of BACE1 gene expression, and might be considered as a novel therapeutic target in treating AD.     

microRNA-21抑制剂联合伊马替尼对慢性髓系白血病K562细胞增殖的影响研究

目的:研究microRNA-21抑制剂(miRZip-21)联合伊马替尼对慢性髓系白血病细胞K562的细胞生长及周期的影响。方法:用慢病毒空载体pmiRZip或表达载体pmiRZip-21转染293TN细胞收获慢病毒颗粒miRZip或miRZip-21,分别感染K562细胞,采用Northern杂交检测microRNA-21的表达;然后对K562细胞进行以下不同处理:miRZip感染、miRZip-21感染、伊马替尼处理和miRZip-21感染与伊马替尼处理联合使用,采用MTT法检测后3种处理后细胞生长情况,流式细胞仪检测4种处理后细胞周期运行情况。结果:与miRZip感染比较,miRZip-21感染导致K562细胞中microRNA-21表达降低,细胞周期运行受到阻滞;而与miRZip-21感染或伊马替尼处理比较,miRZip-21感染与伊马替尼处理联合使用导致K562细胞生长速度明显减慢,细胞存活率显著降低(P<0.05或P<0.01),细胞周期运行也受到严重的阻滞。结论:miRZip-21联合伊马替尼能够协同抑制K562细胞生长及细胞周期运行。     

microRNA-651-5p affects the proliferation,migration, and invasion of lung cancer cells by regulating Calmodulin 2 expression

Objective

Lung cancer is prevalent worldwide and a leading contributor to tumor death. This research intends to explore the molecular mechanism of the microRNA-651-5p (miR-651-5p)/Calmodulin 2 (CALM2) axis in the proliferation, migration, and invasion of lung cancer cells.

Methods

Lung cancer tissues and para-cancerous tissues were collected. The expression levels of miR-651-5p and CALM2 in lung cancer tissues and cells were tested, and the connection between miR-651-5p expression and clinicopathological characteristics of lung cancer patients was further analyzed. The binding sites between miR-651-5p and CALM2 were analyzed and validated. Lung cancer cell proliferation, migration, invasion, and apoptosis were examined.

Results

miR-651-5p was lowly expressed in lung cancer tissues and cells. miR-651-5p expression had no correlation with patients' age and gender but had a correlation with patients' tumor size, TNM stage, and lymph node metastasis. Overexpression of miR-651-5p repressed proliferative, migratory, and invasive behaviors of lung cancer cells. miR-651-5p targeted and negatively regulated CALM2 expression, and CALM2 reversed the inhibiting effects of miR-651-5p on lung cancer cell malignant behaviors, including proliferation, migration, and invasion.

Conclusion

This study expounds that miR-651-5p affects the proliferation, migration, and invasion of lung cancer cells by regulating CALM2 expression.     

肿瘤蛋白 53靶基因 1靶向微小 RNA-33a对胶质瘤细胞增殖、凋亡、迁移、侵袭的影响

目的 探讨肿瘤蛋白53靶基因1(TP53TG1)对胶质瘤细胞增殖、凋亡及迁移侵袭的影响和机制.方法 本研究起止时间为2019年1—6月,人正常神经胶质细胞(HA)和神经胶质瘤细胞U251购于上海斯信生物科技有限公司.实时定量PCR(qRT-PCR)检测HA和U251细胞中TP53TG1的表达水平.构建过表达TP53TG1的U251细胞株,噻唑蓝(MTT)法用于评估细胞增殖能力,流式细胞术分析细胞凋亡,Transwell法测定迁移和侵袭数,Western blotting检测细胞周期蛋白D1(Cyclin D1)、细胞周期蛋白激酶抑制剂(P21)、B细胞淋巴瘤-2(Bcl-2)、Bcl相关x蛋白(Bax)、基质金属蛋白酶2(MMP-2)、E钙黏蛋白(E-cad?herin)表达水平.双荧光素酶报告基因实验和Western blotting验证TP53TG1和微小RNA-33a(miR-33a)的靶向关系.结果 与人正常神经胶质细胞HA比较,神经胶质瘤细胞U251中TP53TG1的表达水平[(1.03±0.10)比(0.28±0.03)]显著降低.过表达TP53TG1能够显著抑制U251细胞活力,下调Cyclin D1、Bcl-2和MMP-2蛋白水平,减少细胞迁移数[(138±14.01)个比(72±7.26)个]和侵袭数[(126±12.54)个比(65±6.63)个],上调P21、Bax和E-cadherin蛋白表达,促进细胞凋亡[(8.16±0.86)％比(22.57±2.65)％].TP53TG1能够靶向负性调控miR-33a的表达.过表达miR-33a能够逆转miR-33a对U251细胞增殖、凋亡[(22.68±2.69)％比(11.36±1.20)％]、迁移[(70±7.05)个比(108±11.37)个]和侵袭[(70±7.05)个比(108±11.37)个]的影响.结论 TP53TG1通过靶向miR-33a抑制胶质瘤细胞增殖、迁移和侵袭,促进细胞凋亡.     

LncRNA ZFAS1靶向miR-373导致肝癌细胞顺铂耐药的机制研究#br#

目的　探究长链非编码RNA（LncRNA）锌指结构反义转录本1（ZFAS1）靶向微小RNA（miR）-373导致肝癌细胞顺铂（DDP）耐药的机制。方法　HepG2细胞设正常培养组、si-NC组、si-ZFAS1组,实时荧光定量PCR（qPCR）检测细胞中ZFAS1、miR-373表达水平。在si-NC组、si-ZFAS1组基础上分别添加0、50、100、200、300 μmol/L DDP处理细胞12 h,CCK-8检测细胞增殖情况,Transwell检测细胞侵袭情况,蛋白免疫印迹检测细胞中基质金属蛋白酶（MMP）2、MMP9蛋白表达水平。双荧光素酶验证ZFAS1与miR-373的靶向关系。在si-ZFAS1组基础上添加inhibitor miR-373,检测细胞中MMP2、MMP9蛋白表达水平。结果　si-ZFAS1组细胞中ZFAS1表达水平均低于正常培养组和si-NC组,miR-373表达水平均高于正常培养组和si-NC组（P＜0.05）。si-NC组和si-ZFAS1组经不同浓度顺铂处理后细胞增殖率、侵袭数量、侵袭蛋白MMP2、MMP9表达水平基本呈降低趋势;si-ZFAS1组上述指标分别低于其对应浓度的si-NC组（P＜0.05）。Starbase分析发现,miR-373与ZFAS1存在互补的结合位点并经双荧光素酶验证。si-ZFAS1+inhibitor miR-373组细胞MMP2、MMP9蛋白表达水平高于si-ZFAS1组和si-ZFAS1+inhibitor NC组（P＜0.05）。结论　ZFAS1可能降低肝癌细胞DDP耐药,其机制可能与调控miR-373有关。     

Association between microRNA-527 and glypican-3 in hepatocellular carcinoma

The present study aimed to identify the specific microRNAs (miRNAs/miRs) and their corresponding target genes involved in hepatocellular carcinomas (HCCs). Microarray analysis was performed to examine the miRNA expression profiles of four paired HCC and corresponding non-cancerous (N) liver tissues using 985 miRNA probes. The Human miRNA Target database was used to identify the target genes of differentially expressed miRNAs between the HCC and N tissues. The protein expression levels of target genes in the HCC tissues and cell lines were evaluated using western blotting. miRNA-mediated suppression of target gene expression was evaluated by transiently transfecting the miRNA into the HCC cell lines. Of the 985 miRNAs evaluated, four miRNAs were differentially expressed (three upregulated and one downregulated miRNAs). Of these four miRNAs, miRNA-527 was highly downregulated in the HCC tissues. Glypican-3 (GPC-3) was predicted as a target gene of miRNA-527. Western blotting revealed that GPC-3 protein is highly expressed in the HCC tissues and HCC cell lines compared with N and normal cell lines. Transfection with miR-527 resulted in suppression of GPC-3 protein expression in the Cos7 cells. Furthermore, transfection with miR-527 also inhibited the intrinsic expression of GPC-3 in the Huh-7 cell line. This indicated that miR-527 in the HCC tissues may be an important novel miRNA that targets the GPC-3 gene expression. GPC-3, whose expression is regulated by miR-527, may be involved in the development and progression of HCC.