miR-182在前列腺癌组织中的表达及其对前列腺癌细胞增殖和凋亡的影响

目的:观察前列腺癌组织及不同前列腺癌细胞系中miR-182的表达,并探讨下调其表达对前列腺癌细胞增殖和凋亡的影响及机制。方法:采用实时荧光定量PCR(q RT-PCR)检测30例前列腺癌组织和30例相应的癌旁组织以及前列腺正常上皮RWPE-1细胞、前列腺癌PC-3、LNCa P和DU145细胞中miR-182的表达,进一步采用Lipfectamine 2000脂质体转染miRNA-182 inhibitor和阴性对照miRNA于PC-3细胞后,通过噻唑蓝(MTT)比色法检测细胞增殖情况,流式细胞术检测细胞凋亡率,免疫印迹(Western blot)法检测转录因子FOXO1、血管内皮生长因子(VEGF)和抑癌基因p53蛋白的表达。结果:miR-182在前列腺癌组织中的表达明显高于癌旁组织(P0.05);miR-182在前列腺癌细胞系PC-3、LNCa P和DU145中的表达均高于前列腺正常上皮细胞RWPE-1(P0.05),其中PC-3细胞中miR-182表达水平最高。转染miRNA-182 inhibitor至PC-3细胞成功下调miR-182表达后,细胞的增殖能力明显受到抑制,细胞凋亡能力明显增强,FOXO1表达水平显著升高,VEGF和p53的表达明显降低,差异均具有统计学意义(P0.05)。结论:miR-182在前列腺癌组织及细胞中呈高表达,下调miR-182的表达可能通过增加FOXO1的表达并减少VEGF和p53的表达,抑制前列腺癌细胞增殖并诱导细胞凋亡。     

miRNA-191对前列腺癌的增殖、迁移侵袭能力的影响及其机制*

目的:观察miRNA-191对前列腺癌的增殖、迁移和侵袭能力的影响,并探讨其机制。方法:分别检测4种人前列癌细胞系(PC-3、DU-145、LNCa P、22RU1)及人正常前列腺细胞RWPE-2中miRNA-191的表达水平,并选择前列腺癌细胞系PC-3作为实验对象。将PC-3细胞分为3组:空白对照组(不转染)、miRNA-191 NC组(Inhibitor NC转染PC-3细胞)、miRNA-191 Inhibitor组(miRNA-191 Inhibitor转染PC-3细胞),每组设置3个复孔。采用RT-qPCR法检测PC-3细胞miRNA-191和PLCD1的mRNA表达水平;采用CCK8法检测PC-3细胞增殖水平;采用划痕实验和侵袭实验分别检测PC-3细胞迁移能力和侵袭能力;通过Targetscan靶基因预测网站,筛选PLCD1作为miRNA-191的靶向蛋白,并用双荧光素酶靶标实验验证;采用Western blot法检测PC-3细胞PLCD1的蛋白表达。结果:与RWPE-2细胞相比,人前列癌细胞中miNRA-191的表达水平显著升高(P＜0.05),且miRNA-191的表达水平在PC-3中较其他3种细胞系显著上调(P＜0.05)。抑制miRNA-191的表达水平后,PLCD1表达水平显著升高,PC-3细胞增殖能力受到抑制,迁移和侵袭能力较空白对照组和miRNA-191 NC组显著降低(P＜0.05)。双荧光素酶报告基因实验结果显示,PLCD1基因是miRNA-191的靶基因。结论:miRNA-191通过靶向PLCD1促进前列腺癌PC-3细胞的增殖、迁移和侵袭能力。     

Plexin-B1 is a target of miR-214 in cervical cancer and promotes the growth and invasion of HeLa cells

Plexin-B1, the receptor for Sema4D, has been reported to trigger multiple and sometimes opposing cellular responses in various types of tumor cells. It has been implicated in the regulation of tumor-cell survival, proliferation, angiogenesis, invasion and metastasis. However, the plexin-B1 gene expression and its regulatory mechanism in cervical cancer remain unclear. The present study shows that plexin-B1 is over-expressed in cervical tumor tissues compared to normal cervical tissues by immunohistochemistry, Western blotting and quantitative RT-PCR. The expression of plexin-B1 is significantly associated with cervical tumor metastasis and invasion according to the analysis of the clinicopathologic data. Plexin-B1 also promotes proliferation, migration and invasion in human cervical cancer HeLa cells. We also found that the plexin-B1 levels are inversely correlated with miR-214 amounts in both cervical cancer tissues and HeLa cells. And miR-214 expression level is also associated with metastasis and invasion of cervical tumor. Furthermore, we demonstrate that plexin-B1 is inhibited by miR-214 through a miR-214 binding site within the 3'UTR of plexin-B1 in HeLa cells. Ectopic expression of miR-214 could inhibit the proliferation capacity, migration and invasion ability of HeLa cells. Our findings suggest that plexin-B1, a target of miR-214, may function as an oncogene in human cervical cancer HeLa cells.     

The Downregulation of MiR-182 Is Associated with the Growth and Invasion of Osteosarcoma Cells through the Regulation of TIAM1 Expression

BackgroundOsteosarcoma is the most common primary bone malignancy in children and young adults. Increasing results suggest that discovery of microRNAs (miRNAs) might provide a novel therapeutical target for osteosarcoma.MethodsMiR-182 expression level in osteosarcoma cell lines and tissues were assayed by qRT-PCR. MiRNA mimics or inhibitor were transfected for up-regulation or down-regulation of miR-182 expression. Cell function was assayed by CCK8, migration assay and invasion assay. The target genes of miR-182 were predicated by bioinformatics algorithm (TargetScan Human).ResultsMiR-182 was down-regulated in osteosarcoma tissues and cell lines. Overexpression of miR-182 inhibited tumor growth, migration and invasion. Subsequent investigation revealed that TIAM1 was a direct and functional target of miR-182 in osteosarcoma cells. Overexpression of miR-182 impaired TIAM1-induced inhibition of proliferation and invasion in osteosarcoma cells.ConclusionsDown-expression of miR-182 in osteosarcoma promoted tumor growth, migration and invasion by targeting TIAM1. MiR-182 might act as a tumor suppressor gene whose down-regulation contributes to the progression and metastasis of osteosarcoma, providing a potential therapy target for osteosarcoma patients.     

SIK1作为miR-93新的靶基因抑制前列腺癌细胞增殖、侵袭和迁移

该文探讨了SIK1作为miR-93新的靶基因对前列腺癌细胞增殖、侵袭和迁移的抑制作用。采用重组质粒pcDNA3.1-SIK1上调前列腺癌细胞中SIK1的表达后,利用CCK8和克隆形成实验检测细胞增殖;利用细胞划痕和Transwell实验检测细胞侵袭和迁移;利用Western blot检测E-cadherin和Vimentin的蛋白表达。采用生物信息学方法预测靶向SIK1 mRNA的3’UTR的miRNAs并进行筛选;双荧光素酶报告实验和Western blot验证miR-93靶向调控SIK1。结果显示,上调SIK1的表达能抑制前列腺癌细胞的增殖、侵袭和迁移,并增加E-cadherin和减少Vimentin蛋白表达;miR-93能够靶向负调控SIK1。总之,SIK1可作为miR-93一个新的靶基因抑制前列腺癌细胞增殖、侵袭和迁移。     

The miR-15a-miR-16-1 cluster controls prostate cancer by targeting multiple oncogenic activities

MicroRNAs (miRNAs) are noncoding small RNAs that repress protein translation by targeting specific messenger RNAs. miR-15a and miR-16-1 act as putative tumor suppressors by targeting the oncogene BCL2. These miRNAs form a cluster at the chromosomal region 13q14, which is frequently deleted in cancer. Here, we report that the miR-15a and miR-16-1 cluster targets CCND1 (encoding cyclin D1) and WNT3A, which promotes several tumorigenic features such as survival, proliferation and invasion. In cancer cells of advanced prostate tumors, the miR-15a and miR-16 level is significantly decreased, whereas the expression of BCL2, CCND1 and WNT3A is inversely upregulated. Delivery of antagomirs specific for miR-15a and miR-16 to normal mouse prostate results in marked hyperplasia, and knockdown of miR-15a and miR-16 promotes survival, proliferation and invasiveness of untransformed prostate cells, which become tumorigenic in immunodeficient NOD-SCID mice. Conversely, reconstitution of miR-15a and miR-16-1 expression results in growth arrest, apoptosis and marked regression of prostate tumor xenografts. Altogether, we propose that miR-15a and miR-16 act as tumor suppressor genes in prostate cancer through the control of cell survival, proliferation and invasion. These findings have therapeutic implications and may be exploited for future treatment of prostate cancer.     

miR-377-5p inhibits lung cancer cell proliferation,invasion, and cell cycle progression by targeting AKT1 signaling

Lung carcinoma is the most common type of malignant tumors globally, and its molecular mechanisms remained unclear. With the aim to investigate the effects of microRNA (miR)-377-5p on the cell development, invasion, metastasis, and cycle of lung carcinoma, this study was performed. We evaluated miR-377-5p expression levels in lung cancer tissues and cell models. Cell viability, proliferation, migration, invasion abilities, and cell cycle distribution were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, crystal violet, transwell, and flow cytometry assay. Furthermore, expression levels of protein kinase B α subunit (AKT1) and proteins related to cell cycle and epithelial-mesenchymal transition (EMT) were assessed using Western blot analysis and quantitative real-time polymerase chain reaction. These results suggested that miR-377-5p was downregulated in vivo and in cell models, and miR-377-5p overexpression inhibited cell viability, proliferation, migration, invasion, and induced cell-cycle arrest. In addition, as a target of miR-377-5p, AKT1 alleviated the decreases of cell viability, proliferation, migration, invasion, the S-phase cells, the expression of cyclin D1, fibronectin, and vimentin, as well as the increases of the G0/G1-phase cells, the expression of Foxo1, p27 ^kip1, p21 ^Cip1 and E-cadherin when miR-377-5p overexpressed. In conclusion, miR-377-5p inhibited cell development and regulated cell cycle distribution and EMT by targeting AKT1, which provided a theoretical basis for further study of lung carcinoma therapeutics.     

MicroRNA-30a functions as tumor suppressor and inhibits the proliferation and invasion of prostate cancer cells by down-regulation of SIX1

Increasing reports have demonstrated that aberrant expression of microRNAs (miRNAs) is found in multiple human cancers. Many studies have shown that down-regulated level of miR-30a is in a variety of cancers including prostate cancer (PCa). However, the precise mechanisms of miR-30a in PCa have not been well explored. In this study, we investigated the biological functions and molecular mechanism of miR-30a in PCa cell lines, discussing whether it could be a therapeutic biomarker of PCa in the future. We found that miR-30a is down-regulated in PCa tissues and cell lines. Moreover, the low level of miR-30a was associated with increased expression of SIX1 in PCa tissues and cell lines. Up-regulation of miR-30a significantly inhibited proliferation of PCa cells. In addition, invasion of PCa cells was suppressed by overexpression of miR-30a. However, down-regulation of miR-30a promoted cell growth and invasion of PCa cells. Bioinformatics analysis predicted that the SIX1 was a potential target gene of miR-30a. Next, luciferase reporter assay confirmed that miR-30a could directly target SIX1. Consistent with the effect of miR-30a, down-regulation of SIX1 by siRNA inhibited proliferation and invasion of PCa cells. Overexpression of SIX1 in PCa cells partially reversed the effect of miR-30a mimic. In conclusion, introduction of miR-30a dramatically inhibited proliferation and invasion of PCa cells by down-regulating SIX1 expression, and that down-regulation of SIX1 was essential for inhibition of cell growth and invasion of PCa cells by overexpression of miR-30a.     

紫杉醇对人肝癌SMMC7721细胞NDRG1表达及增值的影响

旨在探索紫杉醇对人肝癌SMMC7721细胞NDRG1表达的影响,及紫杉醇对肝癌SMMC7721细胞系增殖的抑制作用。分别提取紫杉醇处理前后SMMC7721细胞的RNA,进行逆转录-聚合酶链反应(RT-PCR),判断紫杉醇处理前后肝癌细胞中NDRG1表达的情况;采用蛋白印迹技术(Western blotting)分析紫杉醇处理前后肝癌细胞中NDRG1蛋白表达的情况;应用不同浓度紫杉醇处理肝癌细胞,以MTT法检测处理前后肝癌细胞的抑制率,流式细胞术(FCM)观察细胞周期变化的况。结果表明紫杉醇处理后的肝癌SMMC7721细胞中NDRG1表达下降,紫杉醇浓度越高,NDRG1表达水平越低,具有浓度依赖性。以MTT法观察紫杉醇对肝癌细胞的抑制作用,试验结果表明不同浓度的紫杉醇处理肝癌SMMC7721细胞后,癌细胞被明显抑制;以流式细胞术观察紫杉醇作用后肝癌SMMC7721细胞周期的变化,结果显示G2-M期细胞比例升高的程度随浓度增高而升高,细胞越来越多地被阻滞在G2-M期,不能继续分裂增殖。分化相关基因NDRG1的表达可能是肝癌的发病机制之一,紫杉醇可抑制肝癌SMMC 7721细胞中NDRG1的表达;同时紫杉醇能使肝癌SMMC7721细胞的生长阻滞在G2-M期,从而显著抑制SMMC7721细胞的增殖,并且具有剂量、时间依赖效应。     

Autocrine/Paracrine Human Growth Hormone-stimulated MicroRNA 96-182-183 Cluster Promotes Epithelial-Mesenchymal Transition and Invasion in Breast Cancer

Human growth hormone (hGH) plays critical roles in pubertal mammary gland growth, development, and sexual maturation. Accumulated studies have reported that autocrine/paracrine hGH is an orthotopically expressed oncoprotein that promotes normal mammary epithelial cell oncogenic transformation. Autocrine/paracrine hGH has also been reported to promote mammary epithelial cell epithelial-mesenchymal transition (EMT) and invasion. However, the underlying mechanism remains largely obscure. MicroRNAs (miRNAs) are reported to be involved in regulation of multiple cellular functions of cancer. To determine whether autocrine/paracrine hGH promotes EMT and invasion through modulation of miRNA expression, we performed microarray profiling using MCF-7 cells stably expressing wild type or a translation-deficient hGH gene and identified miR-96-182-183 as an autocrine/paracrine hGH-regulated miRNA cluster. Forced expression of miR-96-182-183 conferred on epithelioid MCF-7 cells a mesenchymal phenotype and promoted invasive behavior in vitro and dissemination in vivo. Moreover, we observed that miR-96-182-183 promoted EMT and invasion by directly and simultaneously suppressing BRMS1L (breast cancer metastasis suppressor 1-like) gene expression. miR-96 and miR-182 also targeted GHR, providing a potential negative feedback loop in the hGH-GHR signaling pathway. We further demonstrated that autocrine/paracrine hGH stimulated miR-96-182-183 expression and facilitated EMT and invasion via STAT3 and STAT5 signaling. Consistent with elevated expression of autocrine/paracrine hGH in metastatic breast cancer tissue, miR-96-182-183 expression was also remarkably enhanced. Hence, we delineate the roles of the miRNA-96-182-183 cluster and elucidate a novel hGH-GHR-STAT3/STAT5-miR-96-182-183-BRMS1L-ZEB1/E47-EMT/invasion axis, which provides further understanding of the mechanism of autocrine/paracrine hGH-stimulated EMT and invasion in breast cancer.     

MicroRNA-21 directly targets MARCKS and promotes apoptosis resistance and invasion in prostate cancer cells

Prostate cancer is one of the most common malignant cancers in men. Recent studies have shown that microRNA-21 (miR-21) is overexpressed in various types of cancers including prostate cancer. Studies on glioma, colon cancer cells, hepatocellular cancer cells and breast cancer cells have indicated that miR-21 is involved in tumor growth, invasion and metastasis. However, the roles of miR-21 in prostate cancer are poorly understood. In this study, the effects of miR-21 on prostate cancer cell proliferation, apoptosis, and invasion were examined. In addition, the targets of miR-21 were identified by a reported RISC-coimmunoprecipitation-based biochemical method. Inactivation of miR-21 by antisense oligonucleotides in androgen-independent prostate cancer cell lines DU145 and PC-3 resulted in sensitivity to apoptosis and inhibition of cell motility and invasion, whereas cell proliferation were not affected. We identified myristoylated alanine-rich protein kinase c substrate (MARCKS), which plays key roles in cell motility, as a new target in prostate cancer cells. Our data suggested that miR-21 could promote apoptosis resistance, motility, and invasion in prostate cancer cells and these effects of miR-21 may be partly due to its regulation of PDCD4, TPM1, and MARCKS. Gene therapy using miR-21 inhibition strategy may therefore be useful as a prostate cancer therapy.