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排序方式: 共有1847条查询结果,搜索用时 15 毫秒
1.
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。 相似文献
2.
Jin Wu Hao Wang Qing Li Qian-Ying Guo Si-Qi Tao Yu-Xian Shen Zheng-Sheng Wu 《Pathology, research and practice》2019,215(9):152523
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. 相似文献
3.
Keishi Kashibuchi Kyoichi Tomita Jack A Schalken Haruki Kume Takumi Takeuchi Tadaichi Kitamura 《International journal of urology》2007,14(9):789-794
OBJECTIVES: To determine the value of the loss of expression of E-cadherin and cadherin associated molecules as useful markers for both prognosis and chemosensitivity in bladder cancer patients who have undergone radical cystectomy. PATIENTS AND METHODS: In 55 paraffin embedded specimens of radical cystectomy at our hospital from 1982 to 2000, the expression of E-cadherin, alpha-, beta- and gamma-catenin was examined by immunohistochemical staining. To evaluate the prognostic significance of these molecules, Kaplan-Meier survival curves were constructed and a statistical analysis was calculated by a log-rank test. A multivariate test (tumor stage, tumor grade, lymph node metastasis, configuration, the expression of E-cadherin, alpha-, beta- and gamma-catenin) was performed to detect prognostic markers. RESULTS: Normal expression was found in 33 cases (60.0%) for E-cadherin, 29 (52.7%) for alpha-catenin, 31 cases (56.4%) for beta-catenin, and 31 cases (56.4%) for gamma-catenin. The expression patterns for E-cadherin, alpha-, beta- and gamma-catenin were significantly correlated with each other (P < 0.01). Survival analysis showed a significant difference between normal and aberrant expression in each staining. A multivariate analysis revealed that the expression of alpha- catenin was an independent prognostic factor (P = 0.0191). In 23 patients that received adjuvant chemotherapy, there was a significant difference in survival between the normal and aberrant expression of alpha-catenin, but not other molecules. CONCLUSION: Alpha-catenin may not only be a good prognostic marker, but also one of key molecules that determine the chemosensitivities in patients with invasive bladder cancer. 相似文献
4.
5.
E-钙黏附蛋白、CD44v6在卵巢上皮性肿瘤及卵巢癌转移灶中的表达 总被引:2,自引:2,他引:0
目的:在基因表达水平上研究黏附分子(E-cadherin,CD44v6)与卵巢癌转移的关系。方法:用免疫组化S-P法,选取1997~2002年间石蜡包埋的卵巢上皮性肿瘤组织块107块,其中良性上皮性肿瘤30例,交界瘤13例,恶性34例(Ⅰ、Ⅱ期4例,Ⅲ、Ⅳ期30例),对30例恶性晚期(Ⅲ、Ⅳ期)病例选取对应的大网膜转移组织。结果:30例良性上皮性肿瘤组织中,E-钙黏附蛋白100%强阳性表达,CD44v6100%阴性。13例交界瘤中,E-钙黏附蛋白有11例(84.6%)强阳性,CD44v6有1例弱阳性表达。34例恶性上皮性肿瘤中,E-钙黏附素有24例(70.6%)阳性表达,CD44v6有11例(32.4%)阳性表达。二指标在良性上皮性肿瘤与卵巢癌之间的阳性表达有显著性差异(P=0.001,P=0.000)。二指标在原发灶和大网膜转移灶之间表达无显著差别(P=1.000,P=1.000)。结论:E-cadherin及CD44v6在上皮性卵巢肿瘤中的表达呈相反趋势,E-cadherin及CD44v6与卵巢癌组织学分级及预后无明显相关性。 相似文献
6.
目的 探讨上皮型钙粘蛋白 (E cadherin ,E cad)在子宫内膜癌中的表达意义。方法 采用免疫组织化学方法检测 16例子宫内膜癌及 10例子宫肌瘤、卵巢囊肿患者 (对照组 )的E cad表达。结果 子宫内膜癌患者的E cad表达阳性率较对照组显著增高 (P <0 .0 5 )。子宫内膜癌E cad表达水平 :①与临床分期相关 ,临床早期表达显著高于晚期 (P <0 .0 5 ) ;②与肿瘤细胞分化程度相关 ,分化越差 ,表达越低 (P <0 .0 5 ) ;③与子宫肌层浸润深度成反比 ,浸润肌层越深表达越低 (P <0 .0 5 )。结论 E cad在子宫内膜癌的侵袭转移中发挥重要的作用 ,它的丢失是癌细胞发生侵袭性生长过程中的关键环节 相似文献
7.
N-cadherin expression in adrenal tumors: upregulation in malignant pheochromocytoma and downregulation in adrenocortical carcinoma 总被引:2,自引:0,他引:2
Cell adhesion molecules (CAMs) are important regulators of tumor growth. The aim of the present study was to evaluate the
expression pattern of CAMs in adrenal tumors regarding origin (cortex vs medulla) and biologic behavior (benign vs malignant).
Eighty-seven adrenal tumors were investigated by immunocytochemistry (ICC) using monoclonal antibodies against N-cadherin
(NCAD), E-cadherin (ECAD), neural cell adhesion molecule (NCAM), and CD44. Western blotting was performed on 30 tumors using
the same antibodies. Markers for proliferation (Ki-67) and catecholamine synthesis (tyrosine hydroxylase) were also analyzed
in tumors by ICC. NCAD was expressed in 12/27 benign pheochromocytomas (BPCs) (12 familial cases), 8/8 malignant pheochromocytomas
(MPCs), 28/30 adrenocortical adenomas, and 9/22 adrenocortical carcinomas. ECAD was expressed in 0/27 BPCs, 0/8 MPCs, 0/30
adrenocortical adenomas, and 2/22 adrenocortical carcinomas. NCAM was expressed in 26/27 BPCs, 7/8 MPCs, 21/30 adrenocrotical
adenomas, and 17/22 adrenocortical carcinomas. CD44 was expressed in 23/27 BPCs, 6/8 MPCs, 7/30 adrenocortical adenomas, and
4/22 adrenocortical carcinomas. Both cortical and medullary adrenal tumors expressed NCAD, NCAM, and CD44 but were devoid
of ECAD. The expression of CD44 and NCAM did not correlate with the malignant potential of tumors. NCAD was upregulated in
MPCs, but downregulated in adrenocortical carcinoma. Thus, NCAD appears to be involved in the development of both cortical
and medullary adrenal tumors. 相似文献
8.
Massimo Pignatelli Tareq W. Ansari Pat Gunter Dan Liu Shinji Hirano Masatoshi Takeichi Günter Klppel Nicholas R. Lemoine 《The Journal of pathology》1994,174(4):243-248
Epithelial cadherin (E-cadherin) is a Ca2+-dependent cell-cell adhesion molecule that connects cells via homotypic interactions. Its function is critical in the induction and maintenance of cell polarity and differentiation, and its loss of downregulation is associated with an invasive and poorly differentiated phenotype in colon and other tumours. We have used an avidin-biotin immunoperoxidase technique to localize E-cadherin in microwave-treated, paraffin-embedded sections from 36 patients with pancreatic adenocarcinomas. E-cadherin was expressed by normal ductal and acinar cells with typical membranous staining at the intercellular junctions. Loss of normal surface E-cadherin expression was found in 19/36 (53 per cent) tumours compared to the adjacent normal ductal cells. Abnormal E-cadherin expression was found more frequently in poorly differentiated (grade III) (6/7, 86 per cent) than in well-differentiated tumours (grade I) (4/14, 28 per cent) (P=0·012). Membranous E-cadherin expression was also lost more frequently in primary tumours with lymph node (stage III) (14/23, 61 per cent) and distant metastasis (stage IV) (2/2, 100 per cent) compared with 3/11 (27 per cent) lymph node-negative tumours (stage I) (P=0·043). In conclusions, our data indicate that loss of membranous E-cadherin expression is associated with high grade and advanced stage in pancreatic cancer. 相似文献
9.
Changes in E-cadherin immunoreactivity in the adenoma-carcinoma sequence of the large bowel 总被引:7,自引:0,他引:7
Giuseppe Gagliardi Olcay Kandemir Michelle Guida Serena Benvestito Gordon W. H. Stamp Massimo Pignatelli Theo G. M. Ruers Irving S. Benjamin John M. A Northover Ian C. Talbot 《Virchows Archiv : an international journal of pathology》1995,426(2):149-154
We have used an avidin-biotin immunoperoxidase technique to localise epithelial cadherin (E-cadherin), a calcium-dependent cell-cell adhesion molecule, in 107 paraffin-embedded sections from 93 patients consisting of 24 with colorectal adenoma, 55 with rectal carcinoma and 14 with liver metastases. The corresponding primary colorectal tumours were also studied in these cases. E-cadherin was expressed by normal colorectal epithelial cells with typical membranous staining at the intercellular junctions. Loss of normal membranous E-cadherin expression and presence of cytoplasmic staining were found frequently in adenomas larger than 1 cm (P<0.01), with high grade dysplasia and villous histology (P<0.01). In primary rectal cancers, loss of membranous expression correlated with high tumour grade. No correlation was seen with Dukes and Jass stage, local extramural spread and 5-year recurrence rate. Complete loss of membranous E-cadherin immunoreactivity was seen in 7/14 (50%) liver metastases in which 6/7 (86%) showed intense membranous E-cadherin immunoreactivity in the corresponding primary tumour. Our data indicate that changes in E-cadherin immunoreactivity and cellular localisation correlate with size, severe dysplasia in adenomas and tumour grade in carcinomas. However, there seems to be no correlation between loss of membranous E-cadherin immunoreactivity and the invasive and metastatic potential of the carcinomas. 相似文献
10.
Differences of E-cadherin expression levels and patterns in primary and metastatic human lung cancer 总被引:6,自引:0,他引:6
Malte Böhm Baldur Totzeck Walter Birchmeier Ilse Wieland 《Clinical & experimental metastasis》1994,12(1):55-62
Normal lung epithelium and 52 lung carcinomas obtained at surgical resection were examined by immunofluorescence for their expression levels and patterns of the calcium-dependent intercellular adhesion molecule E-cadherin. In dysplastic lung tissue and in well-differentiated squamous cell and adenocarcinomas, expression of E-cadherin was confined to the lateral cell border, similar to the expression level and pattern of normal lung tissue. The E-cadherin level was reduced and expression pattern was spotty or diffuse in moderately and poorly differentiated squamous cell and in small cell carcinomas of the lung. Most metastases resected also had a reduced level and an altered pattern of E-cadherin expression. In contrast, no such correlation was found in adenocarcinomas of the lung. This indicates that different cellular mechanisms are responsible in the progression of squamous cell carcinomas and adenocarcinomas of the lung. 相似文献