粘附分子E-钙粘素/β-连环素在LNCaP和ARCaP亚细胞系中的差异性表达及意义

目的:检测粘附分子E-钙粘素/β-连环素(E-cadherin/β-catenin)复合体在LNCaP和ARCaP亚细胞系IF11、IA8中的差异性表达,以探讨E-cadherin/β-catenin复合体与前列腺癌转移侵袭的关系。方法:用Western印迹及免疫荧光鉴定LNCaP和ARCaP亚细胞系IF11、IA8中E-cadherin、β-catenin的表达以及分布情况。结果:Western印迹显示E-cadherin在LNCaP细胞系中表达较高,在IF11、IA8中表达缺失,β-catenin在IF11、IA8中表达显著高于LNCaP(P<0.01)。免疫荧光显示β-catenin在LNCaP细胞系中主要分布在细胞膜上,而在ARCaP亚细胞系IF11、IA8中,主要分布于细胞核中;E-cadherin在LNCaP细胞中主要分布在细胞膜上。结论:不同上皮细胞间质转化态(EMT)特性的前列腺癌细胞系中E-cadherin/β-catenin表达以及分布存在差异,β-catenin的核转位可能是诱发前列腺癌细胞系发生EMT改变的机制之一。

Relationship between the Expression of E-cadherin and Microvessel Density in Lung Cancer and Its Significance

To study the relationship between the expression of E-cadherin andmicrovessel density (MVD) in lung cancer. Methods: The expression of E-cadherin and factor VIII wasdetected in 104 lung cancer tissues by an immunohistochemical method, and MVD was calculated by animage-analysis system. Results: The expression of E-cadherin was significantly related to thedifferentiation of lung cancers (P 【 0.05). A negative correlation was found between E-cadherinexpression and MVD in lung cancer tissues (P=0.047). Conclusion: Down-expression of E-cadherin andan increase of MVD may play an important role in the invasion and metastasis of lung cancer, and mayalso be used as a useful marker for tumor prognosis.

Expression of E-cadherin in gastric carcinoma and its correlation with lymph node micrometastasis

AIM: To examine the expression of E-cadherin in the primary tumor and to evaluate its relationship with lymph node micrometastasis (LNM).METHODS: The authors studied 850 lymph nodes resected from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenectomy using reverse transcription polymerase chain reaction (RT-PCR) assay in addition to H&E staining. Cytokeratin-20 (CK-20)gene marker was used in this assay. The level of E-cadherin expression in the primary tumor was examined by immunochemical technique (EliVisionTM plus).RESULTS: LNM was detected in 77 (12.5%) lymph nodes of 14 patients (46.7%) with gastric carcinoma. The incidence of LNM was significantly higher in the diffuse type (12 of 19 cases, 63.2%) than in the intestinal type of gastric carcinoma (2 of 11 cases, 18.2%, P = 0.026). The incidence of LNM also increased in accordance with the depth of tumor invasion. The loss of expression of E cadherin in primary tumors was found in 14 (46.7) of 30 tumors. The absence of E-cadherin expression was significantly associated with the Lauren classification (P = 0.026), lymph node metastasis (P = 0.011), the grade of differentiation (P = 0.004) and the lymphatic invasion (P = 0.001). Expression of E-cadherin was negative in 10 (71.4%) of the 14 patients with LNM, and in 4 (25%) of the 16 patients without LNM (P = 0.026). CONCLUSION: The current results indicate that the RT PCR assay is useful for the detection of LNM and can significantly increase the detection rate of lymph node metastasis in patients with gastric carcinoma. The Laurenclassification and depth of tumor invasion are significantlyassociated with lymph node micrometastases. Our findings also indicate that E-cadherin may play an important role in determining the growth type and differentiation of gastric carcinoma. The loss of E-cadherin expression may contribute to LNM.

DNA ploidy analysis and expression of MMP-9, TIMP-2, and E-cadherin in gastric carcinoma

AIM： To investigate DNA ploidy and expression of MMP-9, TIMP-2, and E-cadherin in gastric carcinoma and to explore the mechanism of invasion and metastasis of gastric carcinoma. METHODS： Immunohistochemical methods were used to detect the expressions of MMP-9, TIMP-2, and E-cadherin in 156 cases, including 99 cases of gastric carcinoma, 16 cases of adjacent noncancerous mucosa, 16 cases of distant metastases and 25 cases of metastatic lymph node （LN） from gastric carcinoma. Flow cytometry DNA ploidy and S-phase fraction （SPF） analysis were performed on 57 cases, including 47 cases of gastric cancer, 6 cases of adjacent noncancerous mucosa, and 4 cases of distant metastatic cancer. RESULTS： The expression of MMP-9 was significantly correlated with Lauren＇s classification, Borrmann＇s classification, LN metastasis, tumor metastasis, and TNM stage, as well as depth of invasion （all P〈0.05）. The positive rate was lower in noncarcinoma than in carcinoma （31.3% vs 66.7%, P〈0.01）. The expression of TIMP-2 was significantly correlated with Borrmann＇s classification, LN metastasis, and the depth of invasion （all P〈0.05）. The expression of E-cadherin was significantly correlated with differentiation, Lauren＇s classification, Borrmann＇s classification, and LN metastasis, as well as the depth of invasion （P〈0.01 or P〈0.05）. E-cadherin was less expressed in carcinoma than in noncarcinoma （42.4% vs 87.5%, P〈0.01）. There was a positive correlation between MMP-9and TIMP-2 and a negative correlation between MMP-9 and E-cadherin, but no correlation between TIMP-2 and E-cadherin. Also there was a positive correlation between DNA aneuploid rate and differentiation and LN metastasis. SPF that was higher than 15% was positively correlated with tumor size, differentiation and LN metastasis. And there was a significant difference between carcinoma and noncarcinoma in DNA aneuploid rate and SPF. CONCLUSION： With tumor progression and development of heterogeneity, the abnormal expressions of MMP-9, TIMP-2, and E-cadherin or DNA aneuploid rate or high SPF gradually increases, suggesting that they play a crucial role in gastric carcinoma progression. 2005 The WJG Press and Elsevier Inc. All rights reserved

Analysis of metastasis suppressing function of E-cadherin in gastric cancer cells by RNAi

AIM: To study the effect of inhibited E-cadherin expression on invasion of cancer cells.METHODS: We designed the nucleotide sequence of siRNA corresponding to 5' non-coding and coding sequence of E-cadherin. 21-nucleotide dssiRNA was synthesized by in vitro transcription with Ambion Silencer TM siRNA Construction Kit. siRNA was transfected into gastric cancer MKN45 using TransMessenger transfection Kit. RT-PCR and immunofluorescent assay were used to investigate the inhibition of the expression of mutated Ecadherin. Invasive ability of cancer cells was determined by Transwell assay.RESULTS: The synthesis of E-cadherin mRNA rather than protein expression was suppressed dramatically 7 d after interference. Decreased protein expression was observed on d 10 after interference. On d 11, invasion ability was enhanced significantly.CONCLUSION: siRNA targeted at non-coding and coding sequence of E-cadherin showed significant inhibition on mRNA and protein expression. Inhibited E-cadherin expression results in increased invasion ability of cancer cells.

E-cadherin in gastric cancer

Cadherin is an adhesion molecule and a superfamily of calcium-mediated membrane glycoproteins. E-cadherin is the prototype of the class E-cadherin that links to catenins to form the cytoskeleton. Recent evidence has shown that E-cadherin not only acts as an adhesive, but also plays important roles in growth development and carcinogenesis. It has been recently viewed as an invasion as well as a growth suppressor gene. This review summarizes the recent discoveries on E-cadherin and its role in gastric cancer. In particular, our work on E-cadherin in gastric cancer, including its relation with Helicobacter pylori and clinical applications, are described in detail.

Syndrome differentiation in traditional Chinese medicine and E-cadherin/ICAM-1 gene protein expression in gastric carcinoma

AIM： To explore the syndrome differentiation in traditional Chinese medicine （TCM） and gene protein expression in gastric carcinoma METHODS： Preoperative data of gastric cancer cases were collected from the General Surgery Department and classified according to the criteria for syndrome differentiation in TCM. E-cadherin （E-cad） and ICAM-1 gene protein expressions were detected in postoperative specimens from these cases by the immunohistochemical EnVision two-step method. RESULTS： The E-cad positive expression rate was 90% in 100 cases of gastric carcinoma. The difference in E-cad expression was significant between the different syndrome differentiation types in TCM （P 〈 0.01）. Further group-group comparison showed that there was a significant difference in E-cad expression between the stagnation of phlegm-damp type and the deficiency in both qi and blood and the deficiency-cold of stomach and spleen types, where E-cad expression was high. There was no significant difference between the internal obstruction of stagnant toxin type and the in-coordination between liver and stomach type, where E-cad expression was relatively low. The ICAM-1 positive expression rate was 58%, and there was no statistically significant difference between the two groups （x^2= 8.999, P 〉 0.05）. CONCLUSION： E-cad expression is relatively low in the internal obstruction of stagnant toxin type and the incoordination between liver and stomach type, where tumor development and metastasis may be associated with low E-cad expression, or with low homogeneous adhesiveness between tumor cells.

E-cadherin gene C-160A promoter polymorphism and risk of non-cardia gastric cancer in a Chinese population

AIM: To test the hypothesis that E-cadherin gene (CDH1)C-160A promoter variant genotype is associated with an increased risk for developing gastric cancer.METHODS: In this population-based case-control study of gastric cancer in Jiangsu Province, China, we performed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to genotype the C-160A polymorphism of CDH1 promoter in 206 non-cardia gastriccancer patients and 261 age- and sex-matched but unrelated cancer-free controls.RESULTS: The frequencies of genotypes CC, CA and AA were 57.8%, 36.4% and 5.8% in gasfric cancer cases,respectively, and 58.2%, 34.9% and 6.9% in controls respectively. The distributions of CDH1 genotypes were not significantly different between gastric cancer cases and controls (P = 0.87 for genotype frequency and P = 0.92for allele frequency). Compared with the CC genotype, the CA and AA genotypes were not associated with an increased risk for non-cardia gastric cancer (adjusted odds ratios (OR)= 1.15, and 95% confidence interval (95% CI) = 0.78-1.72for CA genotype, and OR = 0.90 and 95% CI = 0.42-2.01for AA genotype).CONCLUSION: E-cadherin gene C-160A promoter polymorphism may not play a major role in the etiology of non-cardia gastric cancer in Chinese population.

Helicobacter pylori infection in relation to E-cadherin gene promoter polymorphism and hypermethylation in sporadic gastric carcinomas

AIM: To study Helicobacter pylori (H pylori) infection in relation to E-cadherin (E-cad) promoter polymorphism and hypermethylation in GCs.METHODS: Specimens were taken from representative cancerous lesions and adjacent non-cancerous epithelia of 67 resected GCs. Hpyloriwas detected by real-time PCR of the cagA gene from non-neoplastic epithelium.E-cad promoter polymorphism and hypermethylation were determined by restriction fragment length polymorphism analysis and methylation-specific PCR, respectively. Expression of E-cad protein was determined by immunohistochemistry.RESULTS: Hpyloriwas found in 57% of patients with GC.H pylori infection was more frequently found in tumors with the -160C/C genotype than those with the -160C/A and -160A/A genotypes (74% vs47%, P = 0.02). Hpylori infection was associated with E-cad methylation in nonneoplastic epithelium; however, no significant difference in H pylori was observed between methylated and unmethylated cancerous lesions.CONCLUSION: Patients with the -160C/C genotype might require Hpyloriinfection to promote the inactivation of CDH1, suggesting that Hpylori infection might affect GC in an initial stage because polymorphism is germ line.Mechanism of hypermethylation of CDH1 promoter in GC is complex, and Hpyloriinfection might affect it in an initial stage.

Syndecan-1 and E-cadherin expression in differentiated type of early gastric cancer

AIM: To elucidate the role and alterations of syndecan-1 and E-cadherin expression in different cellular phenotypes of differentiated-type gastric cancers (DGCs), METHODS: A total of 120 DGCs at an early stage, andtheir adjacent mucosa, were studied both by immunohistochemistry. Syndecan-1 and E-cadherin were assessed by immunohistochemical staining with anti-syndecan-1 and anti-E-cadherin antibodies, respectively. Based on immunohistochemistry, DGCs and their surrounding mucosa were divided into four types: gastric type (G-type),ordinary type (O-type), complete-intestinal type (CI-type),and null type (N-type).RESULTS: Syndecan-1 expression was significantly lower in G-type cancers (29.4%) than in O-type (79.6%) and CI-type cancers (90%) (P＜0.05, respectively), but E-cadherin did not show this result. In addition, syndecan-1 expression was significantly reduced in DGCs comprised partly of poorly differentiated adenocarcinoma or signet-ring cell carcinoma, compared to DGCs demonstrating papillary and/or tubular adenocarcinoma (P＜0.05). G-type intestinal metaplasia (IM) surrounding the tumors was observed in 23.8% of G-type, 4.9% of O-type, and 6.7% of CI-type cancers (P＜0.05; G-type vs O-type). Reduction of syndecan-1 expression was significant in G-type IM (25%) compared to non-G-type IM (75%; P＜0.05).CONCLUSION: Loss of syndecan-1 plays a role in the growth of G-type cancers of DGCs at an early stage, and the reduction of syndecan-1 expression in IM surrounding the tumors may influence the growth of G-type cancer.

E-cadherin and β-catenin expression in pancreatic intraepithelial neoplasia and pancreatic adenocarcinoma

Objective: To investigate the significance of abnormal E-cadherin and β-catenin expression in pancreatic intraepithelial neoplasia (PanIN) and pancreatic adenocarcinoma. Methods:Pancreatic samples of 156 cases were retrospectively studied from surgery and autopsy in Changhai hospital from January 2001 to December 2003, from which tissue microarray blocks containing 129 PanIN-1A lesions, 104 PanIN-1B lesions, 22 PanIN-2 lesions, 11 PanIN-3 lesions, and 121 pancreatic ductal adenocarcinomas and corresponding paracancerous tissues were constructed. EnVision method of immunohistochemistry was used to detect the E-cadherin and β-catenin expression. The correlation between the abnormal E-cadherin and β-catenin expression and clinicopathological parameters was analysed. Results: The rate of E-cadherin abnormal expression was significant in ductal adenocarcinomas compared with the PanIN lesions and normal ducts(64.5%,32.3%,0%), moreover, the rate of E-cadherin abnormal expression was in relation to differentiation, lymph node metastasis and perineural invasion of pancreatic adenocarcinoma(P<0.05). There was remarkable increase in the E-cadherin cytoplasmic expression in PanIN lesions and ductal adenocarcinomas compared with normal ducts. The rate of β-catenin abnormal expression was found to be related with lymph node metastasis and perineural invasion of pancreatic adenocarcinoma(P<0.05). The expression of β-catenin cytoplasm and/or nucleus was significant in high-grade PanIN lesions and ductal adenocarcinomas compared with low grade PanIN lesions or normal ducts(P<0.05). There was a positive relationship between the E-cadherin and β-catenin expression in PanIN lesions and ductal adenocarcinomas (P<0.01, P<0.05). Conclusion: There is aberration in the expression of the E-cadherin and β-catenin in PanIN lesions and ductal adenocarcinomas, suggesting the E-cadherin and β-catenin changes is not only related with the biological action and prognosis, but also involved in pancreatic carcinogenesis.

SERUM SOLUBLE E—CADHERIN LEVEL IN PATIENTS WITH ENDOMETRIOSIS

Objective.To investigate the serum sE cadherin level in patients with endometriosis and the alterations of that level in healthy control during the menstrual cycle.Methods.Thirty two patients with endometriosis and 30 healthy women were tested for serum sE cadherin levels by enzyme linked immunosorbent assay.Results.The serum sE cadherin levels in healthy control did not vary throughout the menstrual cycle,which were lower than those in patients with endometriosis.Conclusions.E cadherin might be involved in endometrial shedding during menstruation in endometriosis patients.The serum sE cadherin assay might be helpful as a serum marker for the diagnosis and management of endometriosis.