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.     

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。     

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。     

酪氨酸激酶受体RON与E-cadherin在子宫内膜异位症上的表达及意义

目的探讨酪氨酸激酶受体RON及上皮型钙粘蛋白(E-cadherin)在子宫内膜异位症(endometriosis,EMs)上的表达及意义。方法选择2017年7~12月深圳市龙岗区人民医院收治的42例EMs患者,术中分别留取新鲜异位内膜组织和在位内膜组织,随机选取子宫切除或诊断性刮宫治疗的非EMs患者42例,术中留取其正常子宫内膜组织。采用逆转录聚合酶链反应(RT-PCR)检测子宫内膜组织中RON mRNA的表达,采用免疫组织化学方法检测对应42例石蜡组织中RON蛋白和E-cadherin的表达,并分析RON蛋白和E-cadherin的相关性。结果EMs异位内膜组织RON mRNA及RON蛋白阳性表达率显著高于在位内膜组织及正常子宫内膜组织(P<0.001),在位内膜组织及正常内膜组织中E-cadherin阳性表达率显著高于异位内膜组织(P<0.001),且异位内膜组织中RON mRNA及RON蛋白的表达与临床分期有关(P<0.001)。在同一标本中RON蛋白和E-cadherin表达呈负相关关系(r=-0.497,P<0.05)。结论RON的过度表达与EMs的发生发展密切相关,联合检测RON和E-cadherin的异常对判断EMs的发生发展有一定的参考价值,RON可能成为诊断治疗EMs的新靶点。     

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。     

Drosophila E-cadherin is required for the maintenance of ring canals anchoring to mechanically withstand tissue growth

Intercellular bridges called “ring canals” (RCs) resulting from incomplete cytokinesis play an essential role in intercellular communication in somatic and germinal tissues. During Drosophila oogenesis, RCs connect the maturing oocyte to nurse cells supporting its growth. Despite numerous genetic screens aimed at identifying genes involved in RC biogenesis and maturation, how RCs anchor to the plasma membrane (PM) throughout development remains unexplained. In this study, we report that the clathrin adaptor protein 1 (AP-1) complex, although dispensable for the biogenesis of RCs, is required for the maintenance of the anchorage of RCs to the PM to withstand the increased membrane tension associated with the exponential tissue growth at the onset of vitellogenesis. Here we unravel the mechanisms by which AP-1 enables the maintenance of RCs’ anchoring to the PM during size expansion. We show that AP-1 regulates the localization of the intercellular adhesion molecule E-cadherin and that loss of AP-1 causes the disappearance of the E-cadherin–containing adhesive clusters surrounding the RCs. E-cadherin itself is shown to be required for the maintenance of the RCs’ anchorage, a function previously unrecognized because of functional compensation by N-cadherin. Scanning block-face EM combined with transmission EM analyses reveals the presence of interdigitated, actin- and Moesin-positive, microvilli-like structures wrapping the RCs. Thus, by modulating E-cadherin trafficking, we show that the sustained E-cadherin–dependent adhesion organizes the microvilli meshwork and ensures the proper attachment of RCs to the PM, thereby counteracting the increasing membrane tension induced by exponential tissue growth.E-cadherin (E-Cad) is a core component of intercellular adhesion complexes in cohesive metazoan tissues. E-Cad assembles into clusters that are stabilized by actin filaments via β- and α-catenin at the level of adherens junctions and form an adhesive belt mechanically linking cells together. A key feature of adherens junctions is their plasticity, which enables tissue remodeling, sustained by a constant endocytosis- and exocytosis-regulated E-Cad turnover (1) that is critical for various morphogenetic processes in epithelia (2–5).Drosophila oogenesis is a rich, multifaceted developmental process during which E-Cad function is not limited to epithelia, because it also regulates intercellular collective migration (6, 7) and the adhesion of stem cells to their niche (8). Cells derived from two different stem cell populations initially assemble into egg chambers composed of a follicular epithelium surrounding a 16-cell germline cyst (GC), itself composed of one oocyte and 15 nurse cells. During the next 64 h, GC cells grow to hundreds of times their initial volume. Oocyte growth is supported by cytoplasmic connections with nurse cells through ring canals (RCs) (Fig. 1 A and B), intercellular bridges that, instead of undergoing abscission, are stabilized on arrested cleavage furrows (9, 10). Recent findings revealed that RCs play a vital role in germline as well as in somatic tissues (10). RCs are composed of a noncontracting subcortical actin ring (11), the inner rim, attached to an electron-dense plasma membrane (PM) (12), the outer rim (Fig. 1A). RCs have been studied mainly in Drosophila female GCs (9) where genetic screens uncovered a variety of actin regulators controlling their establishment at the onset of oogenesis and their growth throughout the entire process (13–17). However, the molecular machinery involved in anchoring the PM to the RC remains unknown. Mutations in several membrane-traffic regulators affect the integrity of nurse cells’ PM, causing multinucleation and giving rise to remnants of detached RCs (18–24); these observations suggest that an unidentified membrane cargo is required for anchoring RCs to the PM.Open in a separate windowFig. 1.Nurse cells’ multinucleation in AP-1 mutant female GCs. (A) Schematic representation of the GC consisting of a single oocyte (Oo, nucleus) connected to 15 nurse cells (blue) via RCs (red) and a surrounding monolayer of about 650 somatic follicle cells (green). (Inset) Schematic representation of a transverse section through the RCs composed of an inner rim [red, containing the Adducin-like Hu-li tai shao (Hts) (13, 15) and the filamin Cheerio (16)] contacting an electron-dense PM (outer rim, black) that itself is connected to the rest of the nurse cell PM (gray). (B) Stereotyped organization of the female GC before and after detachment of nurse cells’ RCs. The oocyte has a gray nucleus; nurse cells have colored nuclei. (C) Stage 8 wild-type and AP-1 mutant [identified by the loss of nuclear localization signal (NLS)::GFP, blue] GCs stained for actin (green) and DAPI (red). Arrows indicate RCs connecting nurse cells in control GCs. Arrowheads indicate RCs floating in the cytoplasm of multinucleated nurse cells in AP-1 mutant GCs (at least one floating ring was observed in 29 of 34 mutant stage 8 or older GCs). (C′) Quantitation of multinucleated AP-1 mutant GCs at stage 7 to stage 9 or older. (D) Maximal projections of 5 µm of anchored and clustered floating RCs in control and AP-1 mutant GCs.Here we describe an RC detachment phenotype in mutants of the clathrin adaptor protein 1 (AP-1), a protein complex regulating polarized membrane protein sorting from the trans-Golgi network and endosomal compartments (25), and provide direct evidence that polarized membrane trafficking to RCs allows an E-Cad–mediated mechanical strengthening of RC anchoring necessary to resist the membrane tension generated by cellular growth.     

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。