RNAi干扰AP-2α对人乳腺癌细胞HER2表达及细胞增殖的影响

目的探讨RNAi干扰转录因子AP-2α对乳腺癌细胞MDA-MB-453中HER2表达及细胞增殖的影响。方法通过siRNA抑制MDA-MB-453细胞中AP-2α的表达,采用半定量RT-PCR和Western blot法,检测其对HER2表达的影响,采用MTT法测定细胞增殖情况。结果siRNA抑制AP-2α表达后,HER2 mRNA及其蛋白水平显著下降,RNAi干扰组与对照组比较MDA-MB-453细胞生长明显受抑制（P〈0.01）。结论AP-2αsiRNA可以下调乳腺癌细胞MDA-MB-453中HER2 mRNA及其蛋白的表达水平,抑制MDA-MB-453细胞的生长,提示AP-2α基因在乳腺癌细胞的发生、发展中具有重要作用,AP-2α可能是HER2过量表达乳腺癌的治疗靶点。     

AGR2 在乳腺癌中的表达及其功能的生物信息学初步分析

目的：利用生物信息学方法分析前梯度蛋白2（anterior gradient protein-2,AGR2）在乳腺癌中的表达情况,并分析预测其所涉及的生物学功能及分子信号通路。方法：挖掘Oncomine 和GEPIA数据库中AGR2 在乳腺癌和正常乳腺组织中的表达情况,分析CCLE数据库中AGR2 在乳腺癌细胞系中的表达水平,同时利用HPA数据库分析AGR2 蛋白在正常和乳腺癌组织中的表达水平,并分析其表达与预后关系。Progno Scan 分析AGR2 表达与预后的关系从CCLE下载乳腺癌相关基因芯片并用R语言筛选AGR2 共表达基因,利用GO功能富集分析和KEGG信号通路分析对AGR2 相关共表达基因进行功能注释。结果：Oncomine和GEPIA数据分析显示AGR2 基因在乳腺癌组织中高表达,CCLE数据分析表明AGR2 在乳腺癌细胞系中显著高表达,HPA数据库免疫组化结果显示乳腺癌组织AGR2 蛋白相对于正常乳腺组织高表达;Progno Scan 分析显示AGR2 高表达提示乳腺癌预后不良。利用R软件共筛选出946 个在乳腺癌中同AGR2 共表达的基因,GO功能富集分析显示,共表达基因主要涉及蛋白定位到细胞周围、蛋白定位到细胞膜、细胞连接组装、细胞基质黏附、细胞连接组成等生物学功能;KEGG分析显示共表达基因主要参与乳腺癌和胃癌进程,并和蛋白聚糖在癌症中的作用及缬氨酸、亮氨酸、异亮氨酸降解通路相关。结论：AGR2 在乳腺癌组织和细胞中均高表达,其可能是乳腺癌中潜在的促癌基因,有望成为乳腺癌治疗的新靶标。     

维生素E琥珀酸酯诱导HER-2过表达乳腺癌细胞凋亡机制的研究

目的:探讨维生素E琥珀酸酯(vitamin E succinate,VES)对HER-2过表达乳腺癌细胞的生长抑制和诱导凋亡作用。方法:MTT法测定VES对乳腺癌MDA-MB-231和MDA-MB-453细胞增殖的抑制作用，应用Western blot法筛选HER-2过表达乳腺癌细胞系，同时检测VES处理后GSK-3、NF-κBp65、caspase 9蛋白在乳腺癌MDA-MB-231和MDA-MB-453细胞中的表达水平，划痕实验与侵袭实验观察VES对乳腺癌细胞体外迁移能力的影响，流式细胞术检测VES对乳腺癌细胞凋亡的作用。结果:VES处理后GSK-3、NF-κBp65、caspase 9蛋白在乳腺癌MDA-MB-453细胞中的表达明显高于在乳腺癌MDA-MB-231细胞中的表达，VES作用于HER-2低表达乳腺癌细胞使其迁移及侵袭能力明显增强，却能够抑制HER-2高表达乳腺癌细胞的迁移及侵袭。VES以直接杀伤方式作用MDA-MB-231细胞，而对MDA-MB-453则以诱导细胞凋亡方式杀伤，VES使HER-2高表达乳腺癌MDA-MB-453细胞发生G1/G0期阻滞。结论:VES促进乳腺癌细胞凋亡是通过影响多条信号传导途径完成的，VES作用于不同HER-2表达乳腺癌细胞其迁移及侵袭能力明显不同，其机制与细胞表面蛋白表达有关。     

bcl-2基因的反义寡核苷酸与三氧化二砷联合对恶性淋巴瘤细胞系凋亡的影响

目的：研究bcl-2基因的反义寡核苷酸与三氧化二砷（As2O3）联合对恶性淋巴瘤细胞系凋亡的影响。方法：采用细胞染色方法观察细胞凋亡的形态，原位末端标记法（TUNEL）检测凋亡细胞，流式细胞仪检测细胞的DNA含量和bcl-2蛋白的表达。结果：10－40μmol/l bcl-2基因的反义寡核苷酸和0．5－2．0μmol/L三氧化二砷均能抑制恶性B淋巴瘤细胞系Raji细胞生长，诱导细胞凋亡，流式细胞仪检测Raji细胞，发现亚G1期细胞明显增多，bcl-2蛋白的表达明显降低，呈现时间剂量依赖效应，两者联合应用比单独应用抑制作用显著。结论：bcl-2基因的反义寡核苷酸与三氧化二砷联合应用，明显抑制恶性B淋巴瘤细胞系生长，促进细胞凋亡。     

BMP-2对人卵巢浆液性囊腺癌HO8910细胞凋亡的影响及机制研究

目的:研究BMP-2对人卵巢浆液性囊腺癌HO8910细胞的影响及其机制.方法:MTT、流式细胞仪技术、Annexin V/PI双染、Hoechst33258染色观察BMP-2对HO8910细胞凋亡的影响,并检测BMP-2作用后HO8910细胞中p21、caspase-3的变化.结果:BMP-2作用后HO8910细胞生长被抑制,凋亡增加,且p21、caspase3的表达较前增强.结论:BMP-2促进HO8910卵巢癌细胞凋亡,抑制其生长.     

5,4'-二-正辛烷氧基-7-二氟亚甲基异黄酮体外抗人类乳腺癌细胞作用

目的 探讨金雀异黄素(Gen)衍生物5,4'-二-正辛烷氧基-7-二氟亚甲基异黄酮(DOdFMG)体外抗人类乳腺癌细胞的作用.方法 平皿克隆形成法检测DOdFMG对人类乳腺癌MCF-7细胞抑制生长和增生作用,琼脂糖凝胶电泳法观测DOdFMG诱导MCF-7细胞凋亡作用,Western blotting 法测定DOdFMG对MCF-7细胞PTEN、pAkt、caspase-3蛋白的表达及活性.结果 DOdFMG抑制MCF-7细胞生长,呈剂量依赖性,比Gen具有更强的抗肿瘤活性,DOdFMG能诱导MCF-7细胞凋亡,DOdFMG处理的MCF-7细胞PTEN蛋白及caspase-3蛋白表达上调,pAkt蛋白表达下调,呈时间剂量依赖性.结论 DOdFMG具有抗人类乳腺癌MCF-7细胞的作用,其机制可能与抑制PKB/Akt通路的信号传导、激活PTEN及caspase-3有关,是一种新型治疗乳腺癌的候选药物.     

SKOV3卵巢癌细胞中雌激素对LRP16的调控作用及其影响

目的：研究雌激素受体ER阳性的卵巢癌细胞系中,E2对LRP16的调控作用以及LRP16对细胞增殖的影响。方法：Northern Blot、Western Blot方法分别检测RNA、蛋白表达水平;生长曲线测定过表达或抑表达LRP16对SKOV3细胞生长特性的影响。结果：雌激素敏感的BG-1细胞系中,E2正调控LRP16的表达;而不同浓度雌激素处理雌激素不敏感SKOV3细胞,LRP16蛋白的表达下降,而ICI182 780对其作用相反;LRP16对SKOV3细胞的生长、增殖有微弱的调节作用。结论：在雌激素不敏感的SKOV3细胞系中,E2对LRP16的调节作用及LRP16发挥的生长调节作用与雌激素敏感的BG-1卵巢癌细胞系及乳腺癌体外研究结果不同。提示雌激素不敏感浆液性卵巢癌中E2对LRP16的调控可能存在新的机制,可能用来解释部分卵巢癌对内分泌治疗敏感性不同的原因。     

RNA干扰抑制BMP-2基因表达对人肝癌SMMC7721细胞增殖和凋亡的影响

目的：设计并化学合成针对骨形态发生蛋白2（BMP-2）的siRNA分子片段,转染人肝癌SMMC7721细胞,观察其对SMMC7721细胞增殖和凋亡的影响。方法：阳离子脂质体法瞬间转染SMMC7721细胞,半定量逆转录聚合酶链反应(RT-PCR)法和Western印迹法检测转染BMP-2-siRNA后细胞BMP-2 mRNA水平和蛋白水平的变化,MTT法和流式细胞术检测转染BMP-2-siRNA后SMMC7721细胞增殖、细胞周期和凋亡的变化。结果：3对特异性BMP-2-siRNA均有效地抑制了BMP-2基因的表达,以siRNA-B抑制效果最好。转染BMP-2-siRNA后SMMC7721细胞的增殖能力明显受到抑制( P <0.05)且明显促进了SMMC7721细胞的凋亡。结论：靶向BMP-2基因的siRNA分子片段可以有效地抑制人肝癌SMMC7721细胞的增殖并促进其凋亡     

CUEDC2通过活化 PI3K／Akt 信号通路促进乳腺癌细胞的生长

目的：探讨 CUE 结构域2（CUE domain －containing 2，CUEDC2）蛋白在人乳腺癌细胞中的生物学作用。方法：人乳腺肿瘤细胞 MCF －7转染的 Myc －CUEDC2真核表达载体，提取转染细胞的总蛋白检测磷酸化 Akt 和总 Akt 的表达变化。利用 CCK －8检测过表达 CUEDC2后 MCF －7细胞的生长。结果：CUEDC2能够活化 Akt，使磷酸化 Akt 表达增加，能够促进人乳腺癌细胞生长。结论：当乳腺癌中 CUEDC2表达增高时，能够引起 PI3K／Akt 信号通路活化，促进肿瘤细胞生长。     

赖氨匹林对乳腺癌ERK信号通路活性及Bcl-2、Bax表达的影响

目的：探讨非选择性环氧合酶一2抑制剂赖氨匹林对体外培养的MDA—MB-231人乳腺癌细胞ERK信号转导通路活性以及Bcl-2、Bax家族蛋白表达的影响。方法：应用MTT比色法分析细胞生长抑制作用，流式细胞技术测定细胞凋亡率，免疫印迹技术检测赖氨匹林对乳腺癌细胞外信号调节蛋白激酶（ERK）／磷酸化（p—ERK）、Bcl-2、Bax表达的影响。结果：与对照组相比，（1-10）mmol／L赖氨匹林作用24h、48h、72h明显抑制MDA—MB-231细胞生长，具有剂量、时间依赖性。（1、5和10）mmol／L赖氨匹林作用24h，细胞早期凋亡率分别为5．81％、10．52％、15．63％，对照组为0．27％。赖氨匹林可下调MDA—MB-231细胞P—ERK的表达水平，但不影响总ERK表达，同时上调Bcl-2的表达，下调Bax的表达。结论：赖氨匹林对MDA—MB-231细胞有抑制增殖、诱导凋亡的作用，其作用机制与抑制乳腺癌ERK信号通路、影响Bcl-2、Bax蛋白表达有关。     

The expression and functional characterization of sigma (sigma) 1 receptors in breast cancer cell lines

Sigma (sigma) receptors have been implicated in cancer. However, to date there is little molecular data demonstrating the role of sigma1 receptors in cancer. Expression of sigma1 receptors in various human cancer cell lines in comparison to non-cancerous cell lines was investigated, using real time RT-PCR and by western blotting with a sigma1 receptor specific antibody. Our results indicate that cancer cells express higher levels of sigma1 receptors than corresponding non-cancerous cells. Localization of the sigma1 receptor was investigated in MDA-MB-231 cells by immunocytochemistry and confocal microscopy, expression was visualized predominantly at the cell periphery. We have tested the effect of sigma1 and sigma2 drugs and a sigma1 receptor silencing construct on various aspects of the metastatic process on two breast cell lines of different metastatic potential and a normal breast cell line. Both sigma1 and sigma2 drugs and the sigma1 receptor silencing construct had effects on proliferation and adhesion for breast cancer cell lines, compared to a non-cancerous breast cell line. This data suggests sigma1 receptor plays a role in proliferation and adhesion of breast cancer cells. Therefore, it is likely to be a potential target for the diagnosis and therapy of breast cancer.     

Constitutive activation of nuclear factor-κB is preferentially involved in the proliferation of basal-like subtype breast cancer cell lines

Constitutive nuclear factor (NF)-κB activation is thought to be involved in survival, invasion, and metastasis in various types of cancers. However, neither the subtypes of breast cancer cells with constitutive NF-κB activation nor the molecular mechanisms leading to its constitutive activation have been clearly defined. Here, we quantitatively analyzed basal NF-κB activity in 35 human breast cancer cell lines and found that most of the cell lines with high constitutive NF-κB activation were categorized in the estrogen receptor negative, progesterone receptor negative, ERBB2 negative basal-like subtype, which is the most malignant form of breast cancer. Inhibition of constitutive NF-κB activation by expression of IκBα super-repressor reduced proliferation of the basal-like subtype cell lines. Expression levels of mRNA encoding NF-κB-inducing kinase (NIK) were elevated in several breast cancer cell lines, and RNA interference-mediated knockdown of NIK reduced NF-κB activation in a subset of the basal-like subtype cell lines with upregulated NIK expression. Taken together, these results suggest that constitutive NF-κB activation, partially dependent on NIK, is preferentially involved in proliferation of basal-like subtype breast cancer cells and may be a useful therapeutic target for this subtype of cancer. ( Cancer Sci 2009; 100: 1668–1674)     

环加氧酶-2 通过调控EMT促进乳腺癌MDA-MB-231 细胞的迁移和侵袭

[摘要] 目的：探讨环加氧酶-2（COX-2）在乳腺癌转移中的作用及其可能的机制。方法：收集从2015 年10 月至2018 年4 月在云南省肿瘤医院接受乳腺切除术的患者中获得的原发乳腺癌组织和脑转移乳腺癌组织临床病理样本共45 例,其中原发30 例、脑转移15 例。采用qPCR检测COX-2 在原位乳腺癌和脑转移乳腺癌组织中的表达。将COX-2 过表达重组病毒（LV6-COX2）或敲减COX-2 重组病毒（LV3-COX2 shRNA1、LV3-COX2 shRNA2）感染人乳腺癌MDA-MB-231 细胞并获得稳转细胞株后,CCK-8法检测COX-2 表达对MDA-MB-231 细胞增殖的影响,划痕实验和Transwell 法检测对MDA-MB-231 细胞迁移和侵袭的影响。qPCR和WB实验分析各组细胞中COX-2 mRNA和蛋白的表达水平,qPCR检测COX-2 表达对MDA-MB-231 细胞内EMT相关基因表达的影响。结果：COX-2 表达水平在脑转移乳腺癌患者组织中显著高于原位乳腺癌组织（P<0.01）;并且与乳腺癌患者肿瘤TMN分期有关。成功构建稳定过表达/敲减COX-2 的MDA-MB-231 细胞株。过表达COX-2 促进MDA-MB-231 细胞的迁移和侵袭（均P<0.01）,同时显著提高MMP2、MMP1、N-cadherin 和vimentin 的表达（均P<0.01）,但对细胞增殖无明显影响;而沉默COX-2 则有相反的作用,且可促进细胞增殖（P<0.05）。结论：COX-2 在脑转移乳腺癌组织中高表达,其可能通过调控EMT过程促进乳腺癌MDA-MB-231 细胞的迁移和侵袭。     

Cyclooxygenase-2 expression during immortalization and breast cancer progression

Identification of molecular aberrations in premalignant human mammary epithelial cells (hMEC), the precursors for breast cancers, is a central goal in breast cancer biology. Recent studies implicated expression of cyclooxygenase 2 (COX-2) as a marker to identify precursor cells for breast cancer. In this study, we analyzed COX-2 expression in preselection and postselection hMEC cells and observed similar COX-2 levels in both cells. Interestingly, immortalization of postselection cells using various methods leads to a dramatic decrease in COX-2 expression. Similar to immortal cells, the majority of breast cancer cell lines expressed low levels of COX-2 protein. Finally, analyses of COX-2 expression in a series of specimens from reduction mammoplasty, adenosis, ductal carcinoma in situ, and infiltrating ductal carcinoma showed down-regulation of COX-2 expression during tumor progression. Importantly, down-regulation of COX-2 using small interfering RNA in cells showed no effect on cell proliferation, anchorage-independent growth, migration, or invasion. These results show that (a) COX-2 overexpression does not seem to predict a breast cancer precursor cell and does not provide advantage for the cell to be transformed; (b) inhibition of COX-2 does not affect hMEC growth and oncogenic behavior in the conditions analyzed; and (c) COX-2 expression is decreased in breast cancer cell lines and cancer specimens as compared with normal mammary epithelial cells.     

The mature bone morphogenetic protein-2 is aberrantly expressed in non-small cell lung carcinomas and stimulates tumor growth of A549 cells

To help identify genes, which may regulate metastasis in lung cancer, we performed representational difference analysis between a patient-derived non-small cell lung carcinoma (NSCLC) and immortalized normal human bronchial epithelial cells. This analysis revealed that bone morphogenetic proteins-2/4 (BMP) mRNA was expressed in the lung carcinoma. BMP-2/4 are known to induce pluripotent cell differentiation, enhance cell migration and stimulate proliferation during embryonic development. Despite being powerful morphogens it is not known whether BMP-2/4 have significant biological activity in human carcinomas. Furthermore, it has not been established whether the mature active BMP-2/4 protein is aberrantly expressed in patient-derived tumors. The purpose of this study was to determine whether the expression of the mature BMP-2/4 protein is disregulated in human lung carcinomas and to establish whether it has adverse biological activity. This study reveals that the mature BMP-2 protein, but not BMP-4, is highly over-expressed in human NCSLC with little to no expression in normal lung tissue or benign lung tumors. The expression of BMP-2 localized specifically to the cancer cells. Recombinant BMP-2 stimulated in vitro, the migration and invasiveness of the A549 and H7249 human lung cancer cell lines. In vivo, recombinant BMP-2 enhanced the growth of tumors formed from A549 cells injected subcutaneously into nude mice. Furthermore, inhibition of BMP-2 activity with either recombinant noggin or anti-BMP-2 antibody resulted in a significant reduction in tumor growth. This study shows that expression of the mature BMP-2 protein is disregulated in the majority of NSCLC. BMP-2 enhancement of tumor cell migration and invasion, as well as stimulating tumor growth in vivo, suggests it has important biological activity in lung carcinomas.