乳腺癌相关长链非编码RNA的研究进展

乳腺癌在女性恶性肿瘤的发病率中高居第一,长链非编码RNA(long non-coding RNA,lncRNA)和乳腺癌的发生发展、转移和预后相关。lncRNAs可与miRNA、mRNA或蛋白相互作用来调节相关基因的表达能力,从而影响乳腺癌的治疗效果及预后情况。     

肝细胞癌相关长链非编码RNA差异表达的研究

目的分析肝细胞癌与正常肝组织中差异表达的长链非编码RNA(lncRNA),发现可能与肝细胞癌发生发展相关的特异lncRNA。方法采用lncRNA表达谱芯片技术检测5例肝细胞癌和其配对癌旁正常组织中的lncRNA,筛选出差异表达的lncRNA。运用分层聚类分析,对所有的lncRNA进行分类。最后从中选择10个lncRNA用RT-PCR进行定量验证。结果有1359个lncRNA表达水平出现显著性差异,差异倍数〉2倍。其中629个显著上调,占46.2%,其中125个表达5倍以上;730个显著下调,占53.7%,其中110个表达5倍以上。聚类分析(1)基因间lncRNA有11706条,其中与已知编码基因相距300 kb的lncRNA共有352条。(2)增强子型lncRNA共有1802条,其中与已知编码基因相距300 kb的lncRNA共有42条。(3)HOX基因簇共有101条。RT-PCR结果有8条lncRNA表达趋势与基因芯片结果一致。对癌组和癌旁组进行检验,有6条差异有统计学意义(P0.05)。结论与癌旁组织比较,lncRNA肝细胞癌组织中的表达水平明显改变,可能与肝细胞癌的发生发展有关。     

长链非编码RNA与病毒和微小非编码RNA关系的研究进展

非编码RNA,包括以miRNA、siRNA和piRNA等为代表的短小RNA和长链非编码RNA.长链非编码RNA,有别于其他小分子非编码RNA,是目前非编码RNA研究的热点.随着研究的不断推进,人们发现lncRNA与物种进化、胚胎发育、物质代谢以及肿瘤发生等都有着密切的联系.microRNA是一类长度为19～ 23个核苷酸的内源性非编码RNA,可以在转录水平或转录后水平调节基因的表达.     

乳腺癌组织中长链非编码RNA-00707的表达及与分子病理分型的相关性

目的 探讨长链非编码RNA-00707(long-chain non-coding RNA-00707,Linc00707)在乳腺癌组织中定性与定量表达,及其与乳腺癌分子病理分型的相关性.方法 建立人源脂肪间充质干细胞与人乳腺癌MCF7细胞间接共培养体系,采用LncR-NAs芯片技术获得Linc00707,应用RNAs...     

长链非编码RNA在卵巢癌中的研究进展

长链非编码RNA (lncRNA)是指长度超过200个核苷酸、具有调控基因表达作用的非编码RNA,近年来,因其具有复杂的生物学功能而引起了研究者的广泛关注.目前研究证实,lncRNA与多种肿瘤的发生发展有着密切的关系,可能参与促进或抑制肿瘤的生长和与肿瘤的转移有关.在卵巢癌中,某些lncRNA也被证实可能参与其致病过程.     

长链非编码RNA与结直肠癌

长链非编码RNA(lncRNA)是一类长度大于200 nt的非蛋白编码RNA分子,能同时与DNA、RNA和蛋白质分子相互作用,通过转录和转录后调控等多种作用机制在结直肠癌中发挥促癌或抑癌的双重作用。lncRNA表达异常或突变在结直肠癌的发生、发展、侵袭和转移过程中扮演着重要角色,且与患者预后密切相关。lncRNA有望为成为结直肠癌新的诊断和治疗靶点。     

长链非编码RNA亚细胞定位和功能的研究进展

长链非编码RNA(lncRNA)的亚细胞定位和其功能息息相关,定位于细胞核时,lncRNA可以维持染色质结构,调控基因转录,参与mRNA的可变剪接;定位于细胞质时参与信号传导、转录后调控、翻译和翻译后修饰;定位于细胞器时协助完成细胞器的功能。lncRNA的亚细胞定位机制与其自身序列、结合蛋白等密切相关。此外通过构建核滞溜载体Snovector、添加胞质定位元件等强制改变lncRNA的亚细胞定位,以及利用APEX2等技术研究lncRNA亚细胞定位和其功能之间的关系,有利于lncRNA疗法的开发。     

长链非编码RNA及其在免疫系统中的研究

长链非编码RNA(lncRNA)一直被认为是“暗物质”而未受到人们的重视,直至2007年,斯坦福大学的研究者报道了同源异型基因转录反义RNA (HOTAIR)作为一种lncRNA可与蛋白复合体polycomb相互作用,并抑制同源异型基因(HOX)的转录,参与生物体生长发育的调节过程.自此之后,lncRNA受到了广泛的关注.lncRNA可以在表观遗传学水平、转录水平、转录后水平调节包括基因印迹、细胞定向分化、细胞增殖、细胞周期、肿瘤、神经退行性疾病、免疫细胞的发育与分化以及机体免疫反应的调节等多种病理生理过程.因而研究lncRNA的定义、分类及其发挥功能的机制具有重要意义.     

长链非编码RNA在结肠癌组织与癌旁组织中的表达研究

目的:筛选出结肠癌差异表达的长链非编码RNA(lncRNA),并分析其在结肠癌组织和相应癌旁组织中的差异表达情况。方法:从lncRNAtor数据库下载结肠癌组织中差异表达的lncRNA数据(Colon adenocarcinoma:Person neoplasm cancer status),包含36例结肠癌组织及29例正常结肠组织,以P0.01且差异表达倍数大于2或小于0.5的条件筛选出lncRNA,并用real-time PCR进一步验证其在60对结肠癌组织及癌旁组织中的表达情况。结果:分析结肠癌lncRNA数据发现,与正常组织相比,结肠癌组织共有50个lncRNA差异表达,其中28个高表达,22个低表达(P0.01)。筛选的4个lncRNA在60对结肠癌及癌旁组织标本中的验证结果为:HNF1AAS1和ZDHHC8P1的表达均上调(P0.01),SUZ12P表达下调(P0.05)。临床Ⅰ-Ⅱ期结肠癌组织中HNF1AAS1的表达水平明显低于Ⅲ-Ⅳ期(P0.05),ROC曲线分析显示,HNF1A-AS1、ZDHHC8P1和SUZ12P诊断结肠癌的ROC曲线下面积(AUC)分别为0.729(敏感性为78%,特异性为67%)、0.617(敏感性为68%,特异性为55%)和0.689(敏感性为65%,特异性为55%)。结论:长链非编码HNF1A-AS1和ZDHHC8P1在结直肠癌组织中表达上调,SUZ12P在结直肠癌组织中表达下调,其表达水平可能与结肠癌的发生存在关联。     

赫赛汀诱导乳腺癌细胞凋亡及对其细胞周期的影响

目的研究免疫靶向治疗药物赫赛汀(Herceptin)对HER-2过表达的乳腺癌细胞凋亡及细胞周期的影响。方法Herceptin处理体外培养的乳腺癌SKBR3细胞系,经MTT试验筛选最佳药物处理浓度和时间的组合,应用荧光显微镜、激光共聚焦显微镜、扫描电镜、透射电镜及流式细胞仪检测乳腺癌细胞凋亡的特征、凋亡细胞百分率及细胞周期的变化。结果在Herceptin作用下,荧光显微镜、激光共聚焦显微镜、扫描电镜、透射电镜观察SKBR3细胞均出现凋亡特征。Annexin/PI染色流式仪测定,药物处理组早期凋亡百分率较对照组显著增加(P<0.01)。流式仪细胞周期分析显示,S期细胞含量下降,而G2期细胞含量上升。结论免疫靶向治疗药物Herceptin可特异性地诱导HER-2过表达的乳腺癌细胞发生凋亡,并可使其生长受阻于G2期。诱导凋亡可能是Herceptin抗肿瘤作用的重要机制之一。     

MCPIP1诱导乳腺癌细胞系MDA-MB-231细胞周期停滞

目的研究单核细胞趋化蛋白诱导蛋白1(MCPIP1)在乳腺癌细胞MDA-MB-231中的作用及机制。方法用脂质体转染法转染细胞,在MDA-MB-231中分别过表达,或敲低MCPIP1并筛选稳定表达shRNA的单克隆;MTT法检测细胞增殖;流式细胞计量技术检测细胞周期;实时荧光定量PCR(q-PCR)检测靶基因半衰期;RNA免疫沉淀法(RNA-IP)检测MCPIP1结合的靶基因;荧光素酶报告基因实验检测调节基因3'非编码区(3'UTR)的能力。结果过表达MCPIP1可显著抑制MDA-MB-231细胞增殖(P0.05),敲低MCPIP1显著促进细胞增殖(P0.05);并分别显著增加或降低G1期细胞百分比(P0.01);MCPIP1显著降低细胞周期素依赖性激酶2(CDK2)、细胞周期素依赖性激酶6(CDK6)、cyclin D1和cyclin E1 mRNAs的半衰期(P0.01);MCPIP1结合细胞周期相关基因(P0.05);MCPIP1显著降低含不同3'UTR的报告基因荧光素酶活性(P0.05)。结论MCPIP1在乳腺癌细胞MDA-MB-231中发挥抑癌作用,诱导细胞周期G_1期停滞可能是其发挥抑癌功能的机制之一。     

Expression of luminal and basal cytokeratins in human breast carcinoma

We have examined basal and luminal cell cytokeratin expression in 1944 cases of invasive breast carcinoma, using tissue microarray (TMA) technology, to determine the frequency of expression of each cytokeratin subtype, their relationships and prognostic relevance, if any. Expression was determined by immunocytochemistry staining using antibodies to the luminal cytokeratins (CKs) 7/8, 18 and 19 and the basal markers CK 5/6 and CK 14. Additionally, assessment of alpha-smooth muscle actin (SMA) and oestrogen receptor status (ER) was performed. The vast majority of the cases showed positivity for CK 7/8, 18 and 19 indicating a differentiated glandular phenotype, a finding associated with good prognosis, ER positivity and older patient age. In contrast, basal marker expression was significantly related to poor prognosis, ER negativity and younger patient age. Multivariate analysis showed that CK 5/6 was an independent indicator for relapse free interval. We were able to subgroup the cases into four distinct phenotype categories (pure luminal, mixed luminal/basal, pure basal and null), which had significant differences in relation to the biological features and the clinical course of the disease. Tumours classified as expressing a basal phenotype (the combined luminal plus basal and the pure basal) were in a poor prognostic subgroup, typically ER negative in most cases. These findings provide further evidence that breast cancer has distinct differentiation subclasses that have both biological and clinical relevance.     

细胞分裂周期相关蛋白7通过增强细胞增殖和干性促进人乳腺癌进程

目的 探讨细胞分裂周期相关蛋白7（CDCA7）在人类乳腺癌中的相关功能及潜在的作用机制。方法 通过癌症和肿瘤基因图谱（TCGA）数据库分析检索出不同乳腺癌亚型差异表达基因,找到在基底型乳腺癌中高表达基因,在这些基因中找到CDCA7,通过临床患者的相关标本做免疫组织化学分析,确定其研究意义,进而建立CDCA7稳转细胞系,通过集落形成实验、成球实验及流式细胞术分析研究其在乳腺癌中的功能,最后通过Real-time PCR及Western blotting实验分析其在乳腺癌中的分子机制。 结果 数据库和免疫组织化学结果均显示,CDCA7在基底型乳腺癌细胞中表达高于其他亚型,高表达的CDCA7预示乳腺癌患者不良预后。在luminal细胞系中稳定地过表达CDCA7后,细胞表现出更强的增殖能力,进入分裂期的细胞明显增多,而凋亡细胞显著减少。同时流式细胞术分析表明,过表达CDCA7的细胞表现出了干细胞标记(CD133, 乙醛脱氢酶)上调。Real-time PCR 和Western blotting结果提示,CDCA7能够上调β-连环蛋白（β-catenin）表达,以此影响Wnt信号通路,并影响细胞增殖和干性。结论 CDCA7作为一个促瘤基因,能够通过依赖β-catenin以及Wnt信号通路的方式来诱导luminal乳腺癌细胞向basal-like亚型转化的能力。     

Establishment and characterization of highly osteolytic luminal breast cancer cell lines by intracaudal arterial injection

Bone is one of the most common metastatic sites of breast cancer, and bone metastasis profoundly affects the quality of life of breast cancer patients. Bone metastasis is commonly observed among all the subtypes of breast cancer; however, its molecular mechanism has been analyzed only in triple‐negative subtype of breast cancer (TNBC). To characterize the molecular mechanisms of bone metastasis of luminal breast cancer, we established a bone‐metastatic model of the MCF7, luminal breast cancer cell line, with enhanced osteolytic activity by intracaudal arterial injection (CAI). Pathological analysis of the established cell lines revealed that they exhibited fierce osteolytic ability by promoting osteoclast differentiation and activity. The signature genes extracted from highly osteolytic MCF7 cell lines were differed from those of bone‐metastatic TNBC cell lines. Our results suggest that unique mechanisms of osteolysis in bone‐metastatic lesions of luminal breast cancer. In addition, several up‐regulated genes in MCF7‐BM (Bone Metastasis) 02 cell lines correlated with poor prognosis with luminal breast cancer patients. Our findings support further study on the bone‐metastatic mechanisms of luminal breast cancer.     

Osthole inhibits proliferation of human breast cancer cells by inducing cell cycle arrest and apoptosis

Recent studies have revealed that osthole,an active constituent isolated from the fruit of Cnidium monnieri(L.) Cusson,a traditional Chinese medicine,possesses anticancer activity.However,its effect on breast cancer cells so far has not been elucidated clearly.In the present study,we evaluated the effects of osthole on the proliferation,cell cycle and apoptosis of human breast cancer cells MDA-MB 435.We demonstrated that osthole is effective in inhibiting the proliferation of MDA-MB 435 cells,The mitochondrion-mediated apoptotic pathway was involved in apoptosis induced by osthole,as indicated by activation of caspase-9 and caspase-3 followed by PARP degradation.The mechanism underlying its effect on the induction of G1 phase arrest was due to the up-regulation of p53 and p21 and down-regulation of Cdk2 and cyclin D1 expression.Were observed taken together,these findings suggest that the anticancer efficacy of osthole is mediated via induction of cell cycle arrest and apoptosis in human breast cancer cells and osthole may be a potential chemotherapeutic agent against human breast cancer.     

Matrix metalloproteinase expression patterns in luminal A type breast carcinomas

Objective: Aberrant expression of individual matrix metalloproteinases has been associated with poor prognosis in various human carcinomas. The current study aimed at defining an RNA expression profile of various MMPs in breast cancer and correlating their expression with clinicopathological parameters. Methods: The RNA expression patterns of 6 MMPs (MMP2, MMP8, MMP9, MMP10, MMP11, MMP13) were determined in 25 breast carcinomas using quantitative RT-PCR and correlated with clinicopathological parameters, including menopausal status, tumor size and grade, and lymph node involvement. Results: We observed high MMP2 levels more frequently in premenopausal than in postmenopausal women (p = 0.02). Analysis of luminal A type invasive ductal carcinomas (19/25), revealed an even stronger association of MMP2 with menopausal status (p = 0.005). Within this subgroup, we also found a correlation between MMP11 and menopausal status (p = 0.02). No correlation was found between MMP expressions and other clinicopathological parameters. In co-expression analyses MMP2-MMP10 and MMP8-MMP9 showed a weak correlation of their expression. Conclusions: Although this is a pilot study, our findings indicate that luminal A invasive ductal carcinomas commonly express high MMP2 and MMP11 levels in premenopausal breast cancer patients and suggest a co-regulation of MMP2-MMP10 and MMP8-MMP9.     

Effects of endogenous insulin-like growth factor binding protein-3 on cell cycle regulation in breast cancer cells

High tissue insulin-like growth factor binding protein-3 (IGFBP-3) expression in breast cancers is associated in some studies with rapid growth and poor outcome. This study examined the effects of endogenous IGFBP-3 in Hs578T breast cancer cells, which are IGF-unresponsive and grow aggressively despite relatively high IGFBP-3 expression. IGFBP-3 downregulation using siRNA was associated with increases in DNA synthesis, the percentage of cells in S phase and viable cell numbers, accompanied by increases in cyclins A and D1, a decrease in p27 expression, and increased phosphorylation of retinoblastoma (Rb) on Ser795. Downregulation of IGFBP-3 inhibited extracellular signal-regulated kinase (ERK) activation and cell migration in a monolayer wound healing assay. These results indicate that endogenous IGFBP-3 is anti-proliferative and pro-migratory in Hs578T cells and that these effects are IGF-independent. Poor outcome in breast tumours expressing high levels of IGFBP-3 may be due to the effects of IGFBP-3 on cell migration rather than cell growth.     

siRNA抑制ErbB2基因的表达及对乳腺癌细胞生长的影响

目的:设计并构建ErbB2的小干扰RNA,检测其对ErbB2蛋白表达的干扰效果,并检测其对乳腺癌细胞ZR75-1生长的影响。方法:设计2条针对ErbB2的siRNA,并克隆到siRNA表达载体pSliencer 2.1-U6 neo上。经酶切和测序证明构建成功后,将其与pcDNA3-FLAG-ErbB2共转染于293T细胞,以及单转siRNA于乳腺癌SKBR3和ZR75-1细胞,通过Western blot分别检测siRNA对外源和内源ErbB2的干扰效果。通过结晶紫实验研究siRNA对ZR75-1生长的影响。结果:Western blot证明构建的两条ErbB2 siRNA均能有效抑制外源和内源ErbB2蛋白的表达,并抑制乳腺癌ZR75-1细胞的生长。结论:构建的siRNA能有效地抑制ErbB2蛋白的表达并抑制ZR75-1细胞的生长。