PAK5通过上皮-间质转化促进人乳腺癌细胞侵袭

目的:探讨p21活化激酶-5（p21-activated kinase 5,PAK5）蛋白对乳腺肿瘤细胞侵袭转移的作用机制。方法:观察PAK5过表达对乳腺癌细胞形态的影响,人乳腺肿瘤细胞MCF-7通过慢病毒感染稳定表达Flag-PAK5。然后提取感染细胞的总蛋白进行蛋白免疫印迹检测上皮-间质转化（EMT）标志物上皮-钙黏蛋白（E-cadherin）,纤维连接蛋白（Fibronectin）和波形蛋白（vimentin）的表达。最后通过Transwell实验检测过表达PAK5对乳腺癌细胞迁移和侵袭的影响。结果:过表达PAK5蛋白能够使细胞形态由鹅卵石样像梭形变化,下调E-cadherin蛋白,促进乳腺癌细胞迁移和侵袭。结论:PAK5可能参与调节乳腺肿瘤细胞发生上皮－间质转化,促进乳腺肿瘤侵袭转移的发生。     

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。     

转录因子Snail调控上皮-间质转型及对肿瘤转移的逆转作用

背景与目的:研究表明转录因子Snail调控上皮-间质转型(epithelialtomesenchymaltransition,EMT)与肿瘤转移有一定的相关性。本研究通过观察Snail促进EMT以及反义Snail对肿瘤细胞EMT的逆转,明确Snail在肿瘤转移中的作用。方法:分别以SnailcDNA转染MDCK细胞,反义Snail转染MDA-MB231细胞。Westernblot法检测上皮性标记基因上皮钙粘附素(E-cadherin)、β-连环素(β-catenin)、角蛋白18(Cytokeratin18)与间质性标记基因纤粘蛋白(Fibronectin)及转移相关基因基质金属蛋白酶-2(MMP-2)、RhoA蛋白的改变;细胞划痕实验、Boyden小室体外侵袭实验反映细胞转移潜能的变化。结果:转染SnailcDNA的MDCK细胞,上皮标记基因E-cadherin、β-catenin、Cytokeratin18蛋白表达下调,而间质及转移相关基因Fibronectin、MMP-2、RhoA蛋白表达增强(P<0.05);细胞体外运动力与侵袭力增加(P<0.05);反义Snail转染MDA-MB231细胞后,其实验结果与经SnailcDNA处理后的MDCK细胞相反。结论:Snail能促进正常上皮细胞发生EMT,拮抗肿瘤细胞Snail的表达可逆转EMT表型、降低肿瘤转移潜能。     

Gli-1信号通路对TGF-β1诱导的人胃癌细胞上皮间质转化和侵袭的影响

目的:探讨核转录因子神经胶质瘤关联癌基因同源物1（glioma associated oncogene homolog 1,Gli-1）对转化生长因子-β1(transforming growth factor-β1,TGF-β1)诱导的人胃癌SGC-7901细胞发生上皮间质转化（epithelial-mesenchymal transition,EMT）的作用机制。方法:体外采用10 ng/ml TGF-β1对胃癌SGC-7901细胞进行处理,使用倒置显微镜观察细胞形态变化,RT-PCR和Western blot检测EMT上皮表型蛋白E-cadherin和间质表型蛋白Vimentin的表达水平;Transwell细胞侵袭实验检测细胞侵袭能力变化,检测TGF-β1 对SGC-7901细胞发生EMT 的影响;同时采用RT-PCR和Western blot检测Gli-1的mRNA和蛋白表达水平。随后进一步采用Gli-1基因特异性阻断剂GANT 61阻断Gli-1表达,并使用TGF-β1（10 ng/ml）对SGC-7901细胞进行处理,RT-PCR 和Western blot检测Gli-1、E-cadherin和Vimentin mRNA 及其蛋白表达水平的改变,并使用Transwell细胞侵袭实验检测阻断Gli-1对SGC-7901细胞侵袭能力的影响。结果:TGF-β1可以诱导人胃癌SGC-7901细胞发生上皮间质转化并促进细胞侵袭。TGF-β1可以在mRNA和蛋白水平下调上皮表型蛋白E-cadherin的表达、提高Gli-1和间质表型蛋白Vimentin的表达。TGF-β1可以明显提高SGC-7901细胞侵袭,而阻断Gli-1后可以抑制TGF-β1诱导的人胃癌SGC-7901细胞上皮间质转化和细胞侵袭。结论:胃癌SGC-7901细胞中Gli-1 可能参与TGF-β1 介导的EMT 的发生,Gli-1 可能作为胃癌基因治疗中的有效靶点发挥作用。     

Snail调控肿瘤细胞上皮间质转化的相关信号通路

肿瘤的转移和侵袭是肿瘤患者死亡的主要原因,肿瘤转移和侵袭的过程中涉及多种因素,上皮间质转化（EMT）是促进其中某一环节的关键因素。转录因子Snail作为肿瘤细胞EMT的关键调控因子,起到了重要的作用。通过对Snail调控肿瘤细胞EMT的相关信号通路的研究,有助于我们更好的理解肿瘤的转移及侵袭机制,为寻找有效的靶点提供理论依据。     

miR-200家族在上皮-间质转化中的研究进展北大核心CSCD

0引言 microRNAs（简称miRNAs）是一类进化上高度保守的小分子非编码RNA,长度为21～23nt左右,具有转录后调控基因表达的功能。在癌组织中,它们的调节功能普遍异常,因此被认为是癌基因或是肿瘤抑制因子。miR．200家族成员通过结合并抑制靶基因mRNA的表达,抑制上皮间质转化、肿瘤细胞迁移、侵袭转移,这些靶基因包括参与上皮-间质转化的ZEBl基因和ZEB2基因,snail2,VEGFR-1,D．cateni/Wnt通路中β-catenin基因,EGFR抑制子抗性基因ERRFI-1和化疗药物抗性基因TUBB3,然而在胃癌细胞或胃癌组织中,由于上皮基因的沉默缺失,miR-200家族成员的表达普遍下降。     

柠檬酸合成酶对卵巢癌SKOV3细胞上皮间质转化的影响

目的:探讨柠檬酸合成酶（citrate synthase,CS）对上皮性卵巢癌（epithelial ovarian cancer,EOC）细胞SKOV3上皮间质转化（epithelial-mesenchymal transformation,EMT）及生物学行为的影响。方法:利用Lipofectamine 2000体外瞬时转染化学法合成的CS siRNA,通过实时荧光定量PCR（quantitative real-time PCR,qRT-PCR)和Western blot检测转染效率;Transwell实验检测转染前后SKOV3细胞侵袭和迁移能力的变化;Western blot检测转染前后上皮标记分子E-cadherin、间质标记分子Vimentin蛋白水平和Wnt通路关键分子β-catenin蛋白水平,实时荧光定量PCR检测转染前后EMT相关转录因子Slug、Snail和Twist的mRNA水平。结果:siRNA干扰序列显著降低SKOV3细胞中CS表达;CS低表达显著抑制SKOV3细胞的侵袭和迁移能力,促进上皮标记分子E-cadherin表达,抑制间质标记分子Vimentin表达,降低Wnt通路关键分子β-catenin表达;EMT相关转录因子Snail和Twist表达显著降低(P＜0.001,P＜0.01),Slug表达下降不显著(P＞0.05)。结论:CS低表达显著抑制卵巢癌SKOV3细胞EMT,其机制可能是通过降低Snail和Twist转录因子实现的,为卵巢癌的转移治疗提供初步的实验及理论基础。     

TWIST表达与恶性肿瘤转移关系的研究进展

Twist是高度保守的碱性螺旋-环-螺旋转录因子,为新近发现的癌基因.Twist能够编码凋亡抑制蛋白,参与多种上皮来源肿瘤细胞的上皮间充质转化(EMT)过程,调控肿瘤血管、淋巴管的生成等过程,与肿瘤的侵袭、转移关系密切.目前已在多种肿瘤中发现Twist表达增高,开展Twist表达与肿瘤的侵袭转移关联性的研究对临床预防、治疗癌症转移意义重大.     

上皮间质转化与肿瘤转移的研究进展

目的:总结上皮间质转化(EMT)的调节机制并揭示其与肿瘤转移的关系。方法:应用PubMed检索及CNKI中国期刊全文数据库检索系统,以上皮间质转化和肿瘤转移为关键词检索2004-2008年的相关文献。纳入标准:1)上皮间质转化调节机制的研究;2)上皮间质转化与肿瘤转移的关系。根据纳入标准,精选60篇文献,最后纳入分析33篇文献。结果:EMT存在于人体多个生理和病理过程中。EMT的发生涉及E-钙连蛋白、TGFβ、wnt信号通路、转录因子以及microRNA等机制的调节,转化为EMT的细胞具有干细胞样属性。结论:EMT与肿瘤细胞的转移关系密切,肿瘤细胞通过EMT获得侵袭能力转移至远端组织,随后MET使间质细胞恢复成上皮细胞,使肿瘤细胞重新获得增殖能力为其转移提供保证。     

上皮间质转化的表观遗传调控

E-钙黏蛋白（E-cadherin）表达丧失是上皮间质转化（EMT）的重要标志,许多EMT转录因子结合到E-cadherin启动子区下调其表达,从而调节EMT。表观遗传调控包括DNA甲基化、组蛋白修饰、微小RNA,均参与EMT相关基因表达调控。研究表明,EMT转录因子协同表观遗传调控因子参与E-cadherin表达。靶向EMT表观调控代表着肿瘤新的治疗方向。     

乳腺癌组织中褪黑素受体MT1和CUEDC2的表达及临床意义

目的 检测乳腺癌组织中褪黑素受体（MT1）与CUE结构域蛋白2（CUEDC2）的表达,探讨二者表达的相关性及临床意义。方法 采用Western blotting和免疫组化SP法检测80例乳腺浸润性导管癌、30例乳腺导管内癌和30例正常乳腺组织中MT1和CUEDC2的表达情况。结果MT1在乳腺浸润性导管癌、乳腺导管内癌、正常乳腺组织中的阳性表达率分别为788％、60.0％和16.7％,三者差异有统计学意义（P＜0.05）;CUEDC2在乳腺浸润性导管癌、乳腺导管内癌的阳性表达率分别为68.8％、53.3％,明显高于正常乳腺组织的13.3％,差异有统计学意义（P＜0.05）。Western bloting半定量检测显示,乳腺浸润性导管癌MT1和CUEDC2表达分别为0.542±0.078和0.461±0.057,均高于正常乳腺组织（P＜0.05）。MT1和CUEDC2表达与乳腺浸润性导管癌患者有无淋巴结转移（P=0.034,P=0.027）和组织学分级（P=0.018,P=0.022）均有关, 但与年龄和肿瘤大小无关（P＞0.05）。乳腺浸润性导管癌中MT1表达与CUEDC2表达呈正相关（r=0.441,P＜0.05）。结论 MT1和CUEDC2高表达与乳腺癌的发生、发展及转移有关,联合检测二者表达可为乳腺癌基因治疗寻找新的干预靶点提供实验依据。     

乳腺癌组织中上皮钙黏蛋白和B细胞淋巴瘤基因2的表达及其临床意义的研究

目的:探讨乳腺癌中上皮钙黏蛋白（E-cadherin）和B细胞淋巴瘤基因2（Bcl-2）的表达及其临床意义。方法:使用免疫组织化学方法检测68例乳腺癌旁正常组织、41例纤维腺瘤组织和74例乳腺癌组织的E-cadherin和Bcl-2的表达水平,并分析乳腺癌患者各病理特征与E-cadherin和Bcl-2表达的相关性。结果:乳腺癌旁正常组织和纤维腺瘤组织中E-cadherin阳性率高于乳腺癌组织,Bcl-2阳性率低于乳腺癌组织,差异具有统计学意义（P均＜0.05）。乳腺癌组织病理分级越高、TNM分期越严重、有淋巴结转移和复发的患者 E-cadherin阳性率低,Bcl-2阳性率高;ER阳性患者E-cadherin阳性率高,Bcl-2阳性率高。组织病理分级低-中分化患者E-cadherin阳性率高于高分化患者,Bcl-2阳性率低于高分化患者,差异具有统计学意义（P均＜0.05）;TNM分期Ⅰ+Ⅱ期患者E-cadherin阳性率高于Ⅲ期,Bcl-2阳性率低于Ⅲ期,差异具有统计学意义（P均＜0.05）;有淋巴结转移患者E-cadherin阳性率低于无转移者,Bcl-2阳性率高于无转移者,差异具有统计学意义（P均＜0.05）;雌激素受体（ER）阴性患者E-cadherin、Bcl-2阳性率低于ER阳性者,差异具有统计学意义（P均＜0.05）;复发患者E-cadherin阳性率低于无复发者,Bcl-2阳性率高于无复发者,差异具有统计学意义（P均＜0.05）;Bcl-2的表达与E-cadherin的表达存在负相关性（r=-0.638,P＜0.05）。结论:乳腺癌组织中E-cadherin表达降低,Bcl-2表达升高,二者与乳腺癌组织病理分级、TNM分期、淋巴结转移、ER和复发有关,E-cadherin和Bcl-2的表达存在相关性。     

Detection of Epithelial-Mesenchymal Transition Markers in High Grade Bladder Cancer and Special Variants of Urothelial Carcinoma

Transitional cell carcinoma is considered the most predominant type of bladder cancer. Bladder can cer can also be found as squamous cell carcinoma that accounts for 5% of the total bladder cancer due to its etiology. The biomarkers associated with grade, prognosis, and stage of the disease are not well proved and known however, many studies have pointed to the association between SNAL/SLUG and Twist2 to the overall survival in patients with bladder cancer. These biomarkers were found to have a crucial role in inhibiting cadherin mediators specifically E-cadherin which are found normally in high level to integrate cell adhesion and normal function of the bladder. This research aims to detect SNAL/SLUG and Twist2 biomarkers in specimens of patients with bladder cancer and to detect their impact on E-cadherin, a tumor suppressor mediator responsible for improving survival and prevent metastasis. Materials and Methods: Using 150 archival tissue blocks from human bladder cancer cases to detect expression of SNAIL/SLUG and Twist2 in relation to loss of E-cadherin by immunohistochemical method. Results: Our results have revealed that in squamous cell carcinoma 40 specimens showed marked Twist 2 expression, and 30 specimens showed marked snail/slug biomarkers expression while poorly differentiated cancer cases showed marked expression of Twist 2 in 60 specimens and marked expression of Snail/slug marked expression in 50 specimens. Both were associated with E-cadherin loss. Among the 100 specimens with transitional cell carcinoma, 70 specimens showed divergent differentiation with 7 subtypes each showed different medium to high expression of Snail/Slug and Twist 2 biomarkers with the loss of E-cadherin. E-cadherin was strongly associated with the inverse increase in SNAL/SLUG and Twist2 biomarkers in urothelial carcinoma. Conclusion: Detection of SNAIL/SLUG and Twist 2 biomarkers in urothelial cancer is an important predictor for the loss of E-cadherin, a cornerstone in urinary bladder cell adhesion and its loss in urothelial carcinoma may contribute to cancer invasion and poor prognosis.     

雄激素受体对乳腺癌细胞增殖及相关分子表达作用的研究进展

乳腺癌是激素依赖性肿瘤。除雌激素外,雄激素在乳腺癌的发生发展中也发挥重要作用。雄激素受体（AR）经雄激素作用激活,通过不同方式调控雌激素受体（ER）及芳香化酶的表达,影响人表皮生长因子受体-2（HER-2）、孕激素受体（PR）、E-钙黏蛋白的转录,对乳腺癌细胞的增殖既有抑制也有促进作用。AR还与雌激素受体调节剂（SERMs）他莫昔芬及芳香化酶抑制剂（AIs）的耐药机制有关。深入研究AR调控乳腺癌分子表达的机制有助于将AR作为治疗靶点,提高乳腺癌内分泌治疗的疗效。     

Lentivirus-mediated shRNA Interference Targeting SLUG Inhibits Lung Cancer Growth and Metastasis

Objective: Lung cancer is a deadly cancer, whose kills more people worldwide than any other malignancy.SLUG (SNAI2, Snail2) is involved in the epithelial mesenchymal transition in physiological and in pathologicalcontexts and is implicated in the development and progression of lung cancer. Methods: We constructed a lentivirusvector with SLUG shRNA (LV-shSLUG). LV-shSLUG and a control lentivirus were infected into the non-smallcell lung cancer cell A549 and real-time PCR, Western blot and IHC were applied to assess expression of theSLUG gene. Cell proliferation and migration were detected using MTT and clony formation methods. Results:Real-time PCR, Western Blot and IHC results confirmed down-regulation of SLUG expression by its shRNAby about 80%~90% at both the mRNA and protein levels. Knockdown of SLUG significantly suppressed lungcancer cell proliferation. Furthermore, knockdown of SLUG significantly inhibited lung cancer cell invasion andmetastasis. Finally, knockdown of SLUG induced the down-regulation of Bcl-2 and up-regulation of E-cadherin.Conclusion: These results indicate that SLUG is a newly identified gene associated with lung cancer growth andmetastasis. SLUG may serve as a new therapeutic target for the treatment of lung cancer in the future.     

FOXC2和E-cad在结肠癌组织中的表达及临床意义

目的 探讨结肠癌组织中叉头框蛋白C2（FOXC2）、E-钙粘附蛋白（E-cad）的表达及临床意义。方法 收集2014年1月至2016年3月70例结肠癌组织和30例癌旁组织,采用免疫组织化学SP法检测上述组织中FOXC2、E-cad的表达情况,分析两者的相关性及与临床病理特征的关系。结果 FOXC2在结肠癌组织中的阳性表达率为74.3％（52／70）,高于癌旁组织的20.0％（6／30）,差异有统计学意义（P＜0.001）;E-cad在结肠癌组织中的阳性表达率为21.4％（15／70）,低于癌旁组织的80.0％（24／30）,差异有统计学意义（P＜0.001）。FOXC2和E-cad在结肠癌组织中的表达与TNM分期、浸润深度、淋巴结转移有关（P＜0.05）,与年龄、性别、肿瘤大小、分化程度无关（P＞0.05）。在结肠癌组织中两者表达呈负相关（r=-0.728,P＜0.05）。结论 FOXC2在结肠癌组织中高表达,而E-cad呈低表达,且两者表达呈负相关,提示FOXC2、E-cad可能共同参与了结肠癌的发生、发展过程。     

Fibrillin-1, induced by Aurora-A but inhibited by BRCA2, promotes ovarian cancer metastasis

While Aurora-A (Aur A) provokes, BRCA2 restrains primary tumorigenesis, the roles of Aur A and BRCA2 in cancer metastasis remains unclear. Here, we show that the metastatic promoting markers SLUG, FBN1, and MMP2, 9, 13 are either stimulated or suppressed by Aur A or BRCA2, but the metastatic suppressors E-cadherin, β-catenin, and p53 are either inhibited or promoted by Aur A or BRCA2, leading to enhanced or reduced cell migration and invasion. Further study suggests that FBN1 inhibits E-cadherin and β-catenin, but stimulates MMP2, 9, 13. Depletion of SLUG abrogates FBN1 and MMP9, but increases E-cadherin, while p53 decreases both SLUG and FBN1. Animal assays demonstrate that FBN1 promotes both ovarian tumorigenesis and metastasis. Clinically, overexpression of BRCA2 or Aur A in ovarian cancer tissues predicts good or poor overall and disease free survivals. High expression of SLUG or FBN1 indicates poor overall survivals, whereas high expression of FBN1 but not of SLUG predicts poor disease free survival. No significant associations between p53 expression and patient survivals were found. Overall, FBN1, acts at the downstream of Aur A and BRCA2, promotes ovarian cancer metastasis through the p53 and SLUG-associated signaling, which may be useful for ovarian cancer diagnosis and treatment.     

喉鳞状细胞癌中COX-2和E-钙黏附素的表达及其意义

目的探讨环氧化酶-2（cyclooxygenase-2,COX-2）和E-钙黏附素（E-cadherin,E-cad）表达与喉鳞状细胞癌（LSCC）发生、发展的关系及其生物学意义。方法应用免疫组织化学方法,检测45例LSCC组织、12例喉不典型增生（AH）和10例正常喉黏膜（NLM）组织中COX-2和E-cad蛋白表达水平。结果 LSCC中COX-2表达阳性率高于喉不典型增生和正常喉黏膜组织（P〈0.05）,而E-cad表达阳性率低于喉不典型增生和正常喉黏膜组织（P〈0.05）。在LSCC组织中COX-2和E-cad表达阳性率分别为77.8%（35/45）和62.2%（28/45）。COX-2高表达和E-cad低表达与LSCC分级和淋巴结转移相关（P〈0.05）。LSCC中COX-2表达与E-cad表达呈负相关（P〈0.05）。结论 COX-2和E-cad表达水平可作为判断LSCC分级、淋巴结转移和预后的重要参考指标。