E-cadherin在妇科三大恶性肿瘤中表达的意义及研究进展

E-钙黏蛋白（E-cadherin）是一种主要存在于人和动物上皮的黏附分子，主要功能是维持正常上皮细胞形态和结构完整性。现已在多种肿瘤研究中发现，E-cadherin表达的下调，极易造成肿瘤细胞向外周组织发生浸润和远端转移，但与E-cadherin相关研究在妇科恶性肿瘤中进展缓慢，E-cadherin在子宫内膜癌、卵巢癌和宫颈癌病变过程的调控机制尚不完全清楚，而且肿瘤的发生和发展是多因素作用的过程，需要进一步加强研究，该文章就 E-cadherin在妇科三大妇科恶性肿瘤中表达的意义及研究进展进行综述。     

E-钙黏蛋白在人非小细胞肺癌细胞多西他赛耐药中的作用

目的:探讨非小细胞肺癌(non-small cell lung cancer,NSCLC)A549、H1299、H358、H441多西他赛（docetaxel，DTX）耐药细胞株与上皮间质转化（epithelial-mesenchymal transition,EMT）的关系，并初步研究逆转E-cadherin的表达对NSCLC细胞多西他赛耐药性的影响。方法:应用Real-time PCR 和Western blot 方法检测上皮间质转化相关标志物E-cadherin、Vimentin、N-cadherin、Snail在亲本细胞和多西他赛耐药细胞之间的表达差异；应用慢病毒载体介导构建稳定表达E-cadherin的NSCLC多西他赛耐药细胞；MTS法检测NSCLC细胞多西他赛耐药特性。结果:与A549、H1299、H358、H441四株亲本细胞相比，多西他赛耐药细胞（A549DTX，H1299DTX，H358DTX，H441DTX）形态呈长梭形，呈上皮间质转化（EMT）样改变。多西他赛耐药细胞中E-cadherin表达下调，Vimentin、N-cadherin、Snail表达上调。成功构建了过表达E-cadherin的NSCLC多西他赛耐药细胞。过表达E-cadherin细胞株细胞形态与空载对照细胞株以及亲本耐药细胞株相比呈间质上皮转化(MET)样改变。MTS结果显示四种不同E-cadherin过表达的NSCLC多西他赛耐药细胞对多西他赛的敏感性均强于其亲本耐药细胞和空载对照细胞。结论:NSCLC多西他赛耐药细胞发生EMT样改变，上调E-cadherin能增加NSCLC多西他赛耐药细胞对多西他赛的敏感性。     

Elevated Src family kinase activity stabilizes E-cadherin-based junctions and collective movement of head and neck squamous cell carcinomas

EGF receptor (EGFR) overexpression is thought to drive head and neck carcinogenesis however clinical responses to EGFR-targeting agents have been modest and alternate targets are actively sought to improve results. Src family kinases (SFKs), reported to act downstream of EGFR are among the alternative targets for which increased expression or activity in epithelial tumors is commonly associated to the dissolution of E-cadherin-based junctions and acquisition of a mesenchymal-like phenotype. Robust expression of total and activated Src was observed in advanced stage head and neck tumors (N=60) and in head and neck squamous cell carcinoma lines. In cultured cancer cells Src co-localized with E-cadherin in cell-cell junctions and its phosphorylation on Y419 was both constitutive and independent of EGFR activation. Selective inhibition of SFKs with SU6656 delocalized E-cadherin and disrupted cellular junctions without affecting E-cadherin expression and this effect was phenocopied by knockdown of Src or Yes. These findings reveal an EGFR-independent role for SFKs in the maintenance of intercellular junctions, which likely contributes to the cohesive invasion E-cadherin-positive cells in advanced tumors. Further, they highlight the need for a deeper comprehension of molecular pathways that drive collective cell invasion, in absence of mesenchymal transition, in order to combat tumor spread.     

The oncogenic impact of RNF2 on cell proliferation,invasion and migration through EMT on mammary carcinoma

Mammary carcinoma (MC) is one of most common malignancy in women, and ring finger protein 2 (RNF2) possesses various roles in vast human tumors. In MC tissues as well as in cell lines RNF2 exhibited high expression, had significant association with tumor size, lymph node status, TNM stage, patients’ poor survival, and promoted cell proliferation, colony formation, cell migration and invasion of MC cell lines which was mediated by downregulation of E-cadherin protein. These data reveal that RNF2 protein plays a vital role in the development of MC and may be a potential therapy target of MC.     

沉默LIMK1抑制人结肠癌SW480细胞上皮-间质转化

目的:研究沉默LIMK1对人结肠癌SW480细胞上皮-间质转化（epithelial-mesenchymal transformation，EMT）的影响。方法:RT-PCR、Western blot、免疫荧光与免疫组化检测沉默LIMK1对EMT相关分子表达的影响。裸鼠实验检测沉默LIMK1对移植瘤生长的影响。结果:RT-PCR检测显示，沉默LIMK1可下调Vimentin和上调E-cadherin mRNA表达(P<0.05)。Western blot显示，沉默LIMK1可明显下调SW480细胞Snail及Vimentin蛋白表达和上调E-cadherin表达(P<0.05)。免疫荧光显示，LIMK1沉默细胞Snail与Vimentin阳性信号较对照组明显减弱，而E-cadherin阳性信号显著增强。裸鼠实验结果显示，沉默组肿瘤生长速度较SW480组明显减慢(P<0.05)。沉默组移植瘤瘤重（0.16±0.079）g较SW480组（0.86±0.165）g明显减少，瘤重抑制率为97.7%(P<0.05)。LIMK1沉默组移植瘤较对照组的Ki-67、Vimentin、Snail与CD34阳性表达明显减弱，而E-cadherin表达明显增加。结论:沉默LIMK1可体外抑制人结肠癌SW480细胞EMT。     

实时荧光定量RT-PCR检测舌癌E-cadherin mRNA的表达

目的:了解E-cadherin在舌癌中的表达及其临床意义.方法:采用实时定量PCR检测29例舌鳞癌患者的癌组织和正常组织中E-cadherin mRNA,分析E-cadherin基因表达与临床病理参数的相关性.结果:舌癌组织中E-cadherin mRNA表达水平2.23±1.16(E-cadherin/β-actin),低于正常组织组8.59±2.71,两组间差异有统计学意义(P＜0.01),E-cadherin mRNA水平与临床病理参数之间无相关性(P＞0.05).结论:E-cadherin的表达下降是舌癌发生过程中的重要事件,实时定量PCR检测E-cadherinmRNA的表达对舌癌早期诊断有重要参考价值.     

缝隙连接蛋白43和E-钙黏素在口腔颌面部鳞癌组织中的表达及意义

目的 :探讨缝隙连接蛋白 43 (Cx43 )和E 钙黏素 (E cad)在口腔鳞癌组织中的表达及其生物学行为的关系。方法 :SABC法对 8例正常口腔鳞状上皮 ,2 9例不同分化程度的口腔鳞癌 (包括舌癌 )石蜡切片进行Cx43和E cad表达的半定量检测 ;同时应用免疫细胞化学对舌癌细胞株 (Tca8113 )Cx43和E Cad的表达进行检测。结果 :Cx43和E cad在正常口腔鳞状上皮主要表达于细胞膜上 ,Cx43和E Cad表达的阳性面积和灰度值在正常口腔鳞状上皮与高分化鳞癌之间无明显差异 (P >0 .0 5 )。但随着病理分级的升高 ,两指标的下降具有统计学意义 (P <0 .0 5 )。在口腔鳞癌组织中 ,Cx43和E cad的表达与组织的分化程度、转移之间有显著性差异 (Cx43 :χ2 =7.42、12 .43 ,P <0 .0 5、P <0 .0 1;E cad :χ2 =7.79、9.688,P <0 .0 5、P <0 .0 1)。同一标本中Cx43和E cad表达具有正相关性和一致性 (r =0 .5 77,P <0 .0 0 0 5 )。结论 :Cx43和E Cad的表达水平可作为口腔鳞癌分化和转移的生物学标志。     

E—cadherin在口腔鳞状细胞癌中的表达及其临床意义

应用E—cadherin（E—CD）单克隆抗体通过免疫组织化学ABC方法，对石蜡包埋的40例口腔鳞状细胞癌标本进行分析，探讨E—CD基因的表达与口腔鳞状细胞癌临床病理的关系。结果表明：E—CD阴性表达和弱阳性表达共16例，占40％，细胞膜和细胞浆均见表达。E—CD基因表达与口腔鳞状细胞癌患者性别、年龄、肿瘤临床分期均无明显关系。而E—CD基因表达减弱或阴性口腔鳞状细胞癌患者比阳性者分化低，浸润深．易见淋巴结转移。提示E—CD表达对判断口腔鳞状细胞癌生物学行为有重要作用，是临床判断其恶性程度和制定治疗方案有价值的参考指标。