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11.
目的探讨上皮间叶转化(EMT)相关蛋白E-、N-cadherin和β-catenin在滑膜肉瘤中的表达及意义。方法收集滑膜肉瘤34例,包括双相型24例和单相纤维型10例,应用免疫组化EnVision两步法检测E-、N-cadherin和β-catenin的蛋白表达水平。结果 (1)E-、N-cadherin和β-catenin在34例滑膜肉瘤中的阳性率分别为52.9%、76.5%、97.1%。E-cadherin在双相型滑膜肉瘤中的阳性率(70.8%)高于单相纤维型(10%)(P<0.05);N-cadherin、β-catenin在双相型和单相纤维型滑膜肉瘤中的阳性率分别为70.8%(17/24)和90%(9/10)、95.8%(23/24)和100%(24/24),差异均无显著性(P>0.05)。(2)在24例双相型梭形细胞成分中E-、N-cadherin和β-catenin的阳性率分别为12.5%(3/24)、50%(12/24)和62.5%(15/24);在10例单相纤维型滑膜肉瘤梭形细胞成分中的阳性率分别为10%(1/10)、80%(8/10)和100%(10/10)。β-catenin在单相纤维型滑膜肉瘤的梭形细胞的表达率高于双相型中的梭形细胞(P<0.05)。(3)在24例双相型滑膜肉瘤中,E-、N-cadherin和β-catenin在上皮样细胞中的阳性率分别为70.8%(17/24)、83.3%(20/24)和95.8%(23/24);在梭形细胞成分中的阳性率分别为12.5%(3/24)、50%(12/24)和62.5%(15/24)。E-、N-cadherin和β-catenin在上皮样细胞中的表达均高于梭形细胞(P<0.05)。(4)在双相型滑膜肉瘤中E-cadherin和N-cadherin、E-cadherin和β-catenin均同时表达的比例较高,在单相纤维型中E-cadherin不表达而N-cadherin、β-catenin表达的比例较高。(5)滑膜肉瘤中E-、N-cadherin和β-catenin的表达与患者年龄、肿瘤大小、组织学分级和临床TNM分期之间差异均无显著性(P>0.05)。结论 EMT相关蛋白E-、N-cadherin和β-catenin均可能参与滑膜肉瘤的组织形态分化,N-cadherin和β-catenin影响双相型和单相纤维型滑膜肉瘤中E-cadherin的表达途径不同,滑膜肉瘤组织中可能存在间叶上皮转化(MET)现象。对其深入研究将有助于阐明滑膜肉瘤浸润和转移的分子机制。  相似文献   
12.
Metastatic pancreatic ductal adenocarcinoma and primary cholangiocarcinoma are morphologically very similar and, therefore, challenging to distinguish in liver biopsies. The distinction is important because surgical management and prognosis differ significantly. Several immunohistochemical markers have been evaluated to aid this diagnosis, but aside from N-cadherin, which labels cholangiocarcinoma, few provide the combination of good sensitivity and specificity. Our laboratory recently developed the novel monoclonal antibody human pancreatic cancer fusion #2 (HPC2) that recognizes pancreatic cancer. We hypothesized that the combination of our new marker and N-cadherin can assist in distinguishing metastatic pancreatic cancer from cholangiocarcinoma. We immunostained resections of 60 pancreatic ductal adenocarcinomas and 31 cholangiocarcinomas for the HPC2 and N-cadherin antigens. We also stained 24 gallbladder adenocarcinomas, 11 ampullary adenocarcinomas, and 10 metastatic colonic adenocarcinomas to the liver. Sections were independently scored by 2 pathologists with good agreement using both markers (κ statistics, 0.62-0.64; P < .0001). HPC2 was observed in 80% of pancreatic cancers (48/60), 82% of ampullary (9/11), and 32% (10/31) of cholangiocarcinomas. N-cadherin stained 27% (16/60) of the pancreas cases and 58% (18/31) of the cholangiocarcinomas. Gallbladder and colon cancers were usually double negative (18/24 and 8/10, respectively). Each marker provided significant likelihood ratios to separate pancreatic cancer (HPC2, 2.48 [1.46-4.19]; P < .0001) from cholangiocarcinoma (N-cadherin, 2.17 [1.3-3.64]; P < .01). The combination of both markers provided even better specificity and positive likelihood ratios. We conclude that HPC2 and N-cadherin significantly improve accurate classification of pancreatic cancer and cholangiocarcinoma.  相似文献   
13.

Introduction

Preeclampsia is a pregnancy-specific disorder and placental factor(s) contribute to the pathogenesis of preeclampsia. Turnover of villous trophoblast is affected by impaired placental perfusion in preeclampsia. Expression and localisation of cadherins and cytokeratins are involved in the pathogenesis of preeclampsia. However, studies describing the associations between cadherins and cytokeratins in preeclampsia are limited. The aim of this study was to investigate the expression of E-cadherin, N-cadherin, cytokeratin 18 and cytokeratin 19 in placentae from women with preeclampsia in order to determine whether their expression differs with disease severity.

Methods

29 preeclamptic placentae and 25 normotensive placentae were included in this study. The expression of E-cadherin, cytokeratin 18, cytokeratin 19 andN-cadherin was quantified by immunohistochemistry and western blotting.

Results

E-cadherin, cytokeratin 18 and cytokeratin 19 were expressed predominantly in the syncytiotrophoblast of the placenta and the expression of E-cadherin, cytokeratin 18 and cytokeratin 19 was significantly increased in preeclampsia compared to normotensive pregnancies. However, there was no significant difference in expression between severe preeclampsia and mild preeclampsia. In addition, there was no difference in the expression of N-cadherin between preeclampsic and normotensive pregnancies.

Discussion

Our data demonstrated increased expression of E-cadherin, cytokeratin 18 and cytokeratin 19 in the syncytiotrophoblast of preeclamptic placentae, but this increase was not correlated with disease severity.

Conclusion

Our data suggests that E-cadherin and cytokeratins are involved in the pathogenesis of preeclampsia.  相似文献   
14.
Glial cell line-derived neurotrophic factor (GDNF) has an essential role in the survival and maturation of the dopaminergic (DA) neurons in the substantia nigra (SN) of mammalian embryonic brain. In addition to Ret, cell adhesion molecules (CAMs) were also proposed to function as transmembrane signaling receptors of GDNF. The present study was to investigate whether these transmembrane receptors of GDNF were correlated with the tyrosine hydroxylase (TH) expression of SN DA neurons during early developmental stage. RT-PCR and Western blot were performed to detect TH expression in SN of perinatal rats at mRNA and protein level respectively; meanwhile, Western blot was performed to detect the expressions of the transmembrane proteins including Ret, neural cell adhesion molecule-140 (NCAM-140), integrin β1 and N-cadherin. The results showed that TH mRNA expression was positively correlated with both Ret and N-cadherin protein, while there was no correlation with NCAM-140 and integrin β1; TH protein expression was correlated with all of these transmembrane molecules. These data suggested that the expression of either TH mRNA or TH protein was subject to the mediation of different transmembrane receptor combinations of GDNF.  相似文献   
15.
目的:对多种转移潜能不同的人前列腺癌细胞“上皮细胞间质转化态”(EMT)特性进行鉴定,并从粘附因素和细胞骨架蛋白角度分析其骨转移潜能获得的分子机制。方法:用W estern印迹法鉴定LNCaP及其亚细胞系C4、C4-2和ArCaP亚细胞系IF11、IA8,以及PC-3、Du145等细胞中上皮型钙粘素(E-cadherin)、神经型钙粘素(N-cadherin)和波形纤维蛋白(V im entin)的表达差异情况,并分析其在前列腺癌转移过程中的作用。结果:E-cad-herin在PC-3、LNCaP、C4、C4-2中表达较高,但在Du145、IF11、IA8中表达极低;而V im entin的表达情况恰恰与E-cadherin相反;N-cadherin在IF11、IA8细胞中呈现显著的高表达状态。结论:转移潜能不同的人前列腺癌细胞株之间存在EMT表型的表达差异,其中PC-3、LNCaP、C4、C4-2是未发生EMT改变的细胞,Du145、IF11、IA8却是EMT化的细胞。EMT表型差异蛋白在解释前列腺癌转移机制方面占据着重要地位。  相似文献   
16.
Protocadherin (Pcad) is a group of molecules obtained by polymerase chain reaction (PCR) utilizing the sequence that is well preserved in the extracellular domain of cadherin. Sano et al. analyzed Pcad (PC42,43) that had been cloned from rats, and found that it basically had homology to cadherin, but contained more than six cadherin repeats with a completely different intracellular domains (Sano et al. 1993). In the present study, of the Pcad (Pcad-1,2) cloned from a human cDNA library, as-yet-unspecified Pcad-2 was analyzed for expression in the human fetal central nervous system (CNS). Northern blot analysis of adult human tissue showed that Pcad-2 was expressed in the brain and the placenta, and that Pcad-2 mRNA was expressed in actively dividing neural tumor cell lines. Monoclonal antibodies against Pcad-2 were then made, and the CNS of fetuses were immunohistochemically stained. The expression was hardly visible at the 6th week of pregnancy, and began to become visible along the nerve fiber in the brain stem at the 8th week, and spread over the entire brain at the 11th week. At the 18th week, however, expression in the nerve fascicles, which had been visible by that time, was no longer visible or had decreased. These results suggest that Pcad-2 appears relatively early in the critical stage of development of the fetal CNS, and is involved in the induction, fasciculation, and extension of axons.  相似文献   
17.
目的:探讨上皮型钙黏附素(E-cadherin)、神经型钙黏附素(N-cadherin)及Snail在非小细胞肺癌(NSCLC)中的表达及其临床意义。方法采用实时荧光定量PCR测定Snail、E-cadherin和N-cadherin基因在10对非小细胞肺癌及其癌旁正常肺组织中的表达情况,同时采用免疫组化法检测105例NSCLC以及41例癌旁组织中Snail、E-cadherin和N-cadherin蛋白的表达。结果与癌旁正常肺组织相比较,非小细胞肺癌组织中E-cadherin的表达显著减少,N-cadherin和Snail表达明显增加(P〈0.05)。NSCLC组织中,Snail的表达与N-cadherin的表达呈明显的正相关(P〈0.05,r=0.21),与E-cadherin的表达呈显著负相关(P〈0.05,r=-0.39),而N-cadherinl的表达与E-cadherin的表达也呈明显负相关(P〈0.05,r=-0.53)。结论非小细胞肺癌组织中, Snail、N-cadherin呈显著高表达,而E-cadherin呈显著低表达,三者可能通过相互作用共同参与NSCLC的发生和发展。  相似文献   
18.
目的 探讨N-cadherin表达在颞叶癫痫发生中的作用.方法 制作慢性颞叶癫痫动物模型并观察其致痫后海马及齿状回组织中细胞损伤和苔藓纤维出芽等可塑性改变,采用免疫组织化学技术检测N-cadherin在大鼠海马及齿状回中的表达,采用t检验、Bivariate相关分析来探讨其与可塑性改变的关系.结果 致痫SD大鼠可以观察到海马神经元损伤、苔藓纤维出芽等可塑性改变,且随时间的延长进行性增加;N-cadherin的表达明显增加,表达的时间和位置均与海马可塑性改变相一致.结论 N-cadherin的表达与神经元损伤呈负相关,可能参与海马可塑性改变的过程,进而影响颞叶癫痫发生.  相似文献   
19.
N-cadherin and beta-catenin are involved in cell adhesion and cell cycle in tumor cells and neural crest. Both are expressed at key stages of Schwann cell (SC) development, but little is known about their function in the SC lineage. We studied the role of these molecules in adult rat derived SC-embryonic dorsal root ganglion cocultures by using low-Ca(2+) conditions and specific blocking antibodies to interfere with N-cadherin function and by using small interfering RNA (siRNA) to decrease beta-catenin expression in both SC-neuron cocultures and adult rat-derived SC monocultures. N-cadherin blocking conditions decreased SC-axon association and reduced axon-induced SC proliferation. In SC monocultures, beta-catenin reduction diminished the proliferative response of SCs to the mitogen beta1-heregulin, and, in SC-DRG cocultures, beta-catenin reduction inhibited axon-contact-dependent SC proliferation. Stimulation of SC cultures with beta1-heregulin increased total beta-catenin protein amount, phosphorylation of GSK-3beta and beta-catenin presence in nuclear extracts. In conclusion, our findings suggest a previously unrecognized contribution of beta-catenin and N-cadherin to axon-induced SC proliferation.  相似文献   
20.
神经型钙黏附蛋白(N-cadherin)在上皮恶性肿瘤中表达上调,且与上皮-间质转换关系密切,N-cadherin高表达提示肿瘤的能动性和转移能力增强,在肿瘤的发生、浸润、转移、血管生成中起了重要作用。ADH-1作为N-cadherin抗体的一个全身性抗癌药,诱导靶细胞的凋亡,破坏肿瘤组织中的血管,通过破坏胞外N-cadherin间的黏附,改变N-cadherin和成纤维细胞生长因子受体(FGFR-1)间的关系,破坏FGFR-1,导致FGFR-1表达缺失,从而破坏肿瘤血管,抑制肿瘤的生长,为临床肿瘤的治疗提供了理论基础。  相似文献   
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