E-cadherin Gene Promoter Methylation Research Articles

Decreased promoter methylation of E-cadherin gene due to overexpression of TET enzyme by vitamin C in MCF-7 cell line

E-cadherin (CDH1) is a well-known tumor suppressor gene. The loss of CDH1 gene function caused by genetic or epigenetic alterations may consequently result in tumorigenesis. Vitamin C is an essential factor for epigenetic regulation and its great furnished potential in epigenetic therapy in cancer patients. The present study aims to evaluate the effect of vitamin C on promoter methylation of the CDH1 gene and its possible correlation with the expression of CDH1 in the MCF-7 cell line. CDH1 expression was studied by reverse transcription-polymerase chain reaction (RT–PCR) analysis in MCF-7 cell line that was treated with different concentrations of vitamin C. TET enzyme activity was measured by ELISA. Promoter methylation of CDH1 was studied by Methylation-Sensitive High-Resolution Melting (MS-HRM) analysis of bisulfite-modified DNA. Our results showed that vitamin C increase not only TET enzyme activity but also TET gene overexpressed. In the following, cause to CDH1 gene promoter demethylation and upregulation of CDH1 gene in MCF-7 cell line. Cancer cells may respond to vitamin C induces CDH1 expression by promoter demethylation due to TET enzyme overexpression. • Vitamin C can increase E-cadhrerin gene expression by TET enzyme. • Vitamin C not only increases TET activity, but also TET gene expression. • TET enzyme induces E-cadherin and TET gene by demethylation of their genes.

Does hypermethylation of CpG island in the promoter region of the E-cadherin gene increase the risk of lung cancer? A meta-analysis.

BackgroundHypermethylation of the CpG island in the promoter regions of tumor suppressor genes is common in the cancer tissue of non‐small cell lung cancer (NSCLC) patients. Epithelial cadherin (E‐cadherin) is a classic tumor suppressor gene of the cadherin superfamily and its promoter region is usually hypermethylated in malignant carcinomas. However, whether hypermethylation of the CpG island in the promoter region of E‐cadherin increases the risk of lung cancer is unknown. We conducted a meta‐analysis of E‐cadherin gene promoter methylation status in cancer tissue (CT) and autologous controls (AC).MethodsElectronic databases were searched for E‐cadherin gene promoter methylation and NSCLC. The hypermethylation status between CT and AC of NSCLC patients were compared and pooled by random or fixed effect models according to statistical heterogeneity across the included studies.ResultsEleven publications relevant to E‐cadherin gene promoter hypermethylation and lung cancer risk were identified and included. E‐cadherin gene promoter hypermethylation frequency in CT and AC was 0.32 (95% confidence interval [CI] 0.22–0.41) and 0.12 (95% CI 0.04–0.20), respectively, with statistical difference (P < 0.05). Significant statistical heterogeneity was found across the 11 studies (I2 = 54.5, P < 0.05). The data was pooled through a random effect model with an odds ratio of 4.21 (95% CI 2.33–7.58) in CT compared to AC.ConclusionThe frequency of E‐cadherin promoter hypermethylation in CT is significantly higher than in AC, indicating that promoter hypermethylation of E‐cadherin plays an important role in NSCLC carcinogenesis.

Downregulation of E-cadherin expression in breast cancer by promoter hypermethylation and its relation with progression and prognosis of tumor.

Breast cancer is the most common cancer in women around the world, and novel prognosis strategies is needed to control more accurate and effective of this malignant disease. Among the latest prognostic markers is E-cadherin, which mediates cell-cell adhesion by associating with catenins. Loss of E-cadherin gene (CDH1) function by genetic or epigenetic alteration leads to tumorigenesis. The aim of our study was to investigate E-cadherin gene promoter methylation in breast cancer, and its correlation with E-cadherin protein expression. Fifty primary breast cancers tissue with ductal type and 50 normal breast sample from the same patients that was located adjacent to tumor region as controls were provided by Imam Reza-based referral and teaching hospital affiliated to Tabriz University of Medical Sciences, Tabriz, Iran. CDH1 promoter region CpG sites methylation and E-cadherin protein expression were determined by bisulfite-specific polymerase chain reaction and Western blot analysis, and the resulting products were sequenced on an ABI automated sequencer for firm conclusion. CDH1 hypermethylation in breast tumor specimen (ductal type) was observed in 94 % (47 of 50) comparing with normal samples methylation, and the significant difference was (p = 0.000). Protein expression in tumor samples tends to diminish with the CDH1 promoter region methylation. In the group of 50 ductal carcinomas cases, most of the cases showing CDH1 hypermethylation correlated inversely with the reduced levels of expression of E-cadherin proteins (95 % of full-methylated tumor samples had no protein expression, and 4.5 % of them had weak expression levels). Possible association was observed between CDH1 methylation and its protein expression (p = 0.000). The results of methylation analysis in promoter region in ten CpG sites (863, 865, 873, 879, 887, 892, 901, 918, 920, and 940) suggested that abnormal CDH1 methylation occurs in high frequencies in ductal breast tumors probably sounds the process of carcinogenesis progression.

Promoter methylation and polymorphism of E-cadherin gene may confer a risk to prostate cancer: a meta-analysis based on 22 studies.

Emerging evidence has suggested that -160C/A polymorphism and promoter methylation of E-cadherin gene may contribute to the risk of prostate cancer. However, the results are still conflicting. We aim to systematically evaluate the potential of promoter methylation and polymorphism in E-cadherin gene to confer a risk to prostate cancer through meta-analysis. PubMed, Embase, Web of Science, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI) databases were searched to identify eligible studies published before April 1, 2014. Pooled odds ratios (ORs) with their 95 % confidence intervals (95 % CIs) were calculated by using the random-effect model or the fixed-effect model, according to heterogeneity test. Subgroup analyses were also performed to explore the potential sources of heterogeneity. Sensitivity and publication bias analyses were used to test the robustness of our results. We performed a meta-analysis of 22 included studies, with 11 on -160C/A polymorphism and another 11 on promoter methylation of E-cadherin gene. Our meta-analysis results suggested that E-cadherin -160C/A polymorphism may be a potential risk factor for prostate cancer. Furthermore, we observed that the frequencies of promoter methylation of E-cadherin gene in the prostate cancer tissues were significantly higher than those of normal tissues, indicating that promoter methylation of E-cadherin gene may play an important role in prostate carcinogenesis. In conclusion, the present meta-analysis provides further evidence that promoter methylation and -160C/A polymorphism of E-cadherin gene may confer a risk to prostate cancer. Identifying these risk factors for prostate cancer will improve early detection, allow for selective chemoprevention, and provide further insights into its disease mechanisms.

E-cadherin gene methylation in lung cancer.

E-cadherin, a tumor repressor gene, has been shown to play an important role in maintaining the polarity and structural integrity of epithelial and is closely associated with tumorigenesis, invasion, and metastasis. The current study aimed to investigate the effects of E-cadherin methylation on lung cancer (LC) quantitatively through a meta-analysis. We searched electronic databases to identify eligible studies from their inception through September 30, 2013. Pooled odds ratio (OR) with 95 % confidence interval (CI) was used to assess the relationship between E-cadherin gene methylation and LC risk. A hazard ratio (HR) with 95 % CI was used to assess the impact of E-cadherin gene methylation on overall survival (OS) of LC patients. Seventeen studies comprising 983 LC cases and 669 controls met the inclusion criteria. Summary results revealed that hypermethylation frequencies in LC tissues were significantly higher than those in normal control tissues (OR = 4.11, 95 % CI 2.78-6.07, P < 0.001). Subgroup analysis indicated that higher methylation frequencies were observed in Asian population. Interestingly, we found that hypermethylation of E-cadherin was associated with significantly better survival with HR of 0.47 (95 % CI 0.31-0.71). This meta-analysis revealed that E-cadherin gene promoter methylation was associated with an increased risk of LC, especially in Asian population, and methylated E-cadherin predicted long survival in patients with LC. However, further studies with large numbers of patients will be needed to confirm the findings.

Altered expression of β-catenin, E-cadherin, and E-cadherin promoter methylation in epithelial ovarian carcinoma

The aim of the study was to evaluate the immunoexpression of E-cadherin, β-catenin, and Ki-67, as well as the promoter methylation of E-cadherin gene in epithelial ovarian cancer (EOC), as well as to find a possible relationship between the immunoexpression and hypermethylation. Promoter methylation was studied using methylation-specific PCR in 86 malignant cases, 14 low malignant potential (LMP) tumors and 19 benign cystadenomas. Immunohistochemical expression was carried out in 64 malignant cases, 8 LMP tumors, and 11 benign cystadenomas. Immunoexpression of E-cadherin was reduced in EOC, while 100 % expression was seen in LMP tumors and benign cystadenomas. An interesting observation was the nuclear expression of E-cadherin in a high percentage of cancers, which showed a positive correlation with Ki-67. Β-Catenin expression showed heterogeneous localization with increased nuclear localization, which was significantly higher in cases that did not express E-cadherin. Promoter methylation of E-cadherin was 36, 14, and 11 % in EOC, LMP tumors, and benign cystadenomas, respectively. Our results suggest that reduced expression of E-cadherin is associated with promoter methylation of E-cadherin gene, in addition to providing evidence for the aberrant nuclear localization of E-cadherin in EOC.

Dynamic changes in E-cadherin gene promoter methylation during metastatic progression in papillary thyroid cancer

Thyroid cancer cells undergo epithelial to mesenchymal transition (EMT) in the invasive front of tumor. To determine whether the mesenchymal feature of invasive cancer cells is maintained in metastatic sites, we examined E-cadherin methylation and E-cadherin expression in 66 papillary thyroid cancer (PTC) samples and in 34 corresponding lymph node metastases (LNM). Relationships between E-cadherin and cell motility were evaluated using thyroid cancer cell lines. Hypermethylation of the E-cadherin gene promoter was detected in 39.3% of the PTCs, and loss of E-cadherin expression correlated with lymphocytic infiltration, extrathyroidal invasion and the presence of metastases. Comparing primary PTCs to the corresponding LNM, E-cadherin methylation status was identical in 60% of the cases. The switch in E-cadherin promoter status from unmethylated in PTCs to hypermethylated in LNM was detected in 5%; and from hypermethylatated in PTCs to unmethylated in LNM in 35%. Loss of epigenetic silencing in LNM was associated with a gain of E-cadherin expression. Hypermethylation of the E-cadherin gene promoter was detected in thyroid cancer cell lines with mesenchymal-like morphology. Loss of E-cadherin expression in these cells correlated with high migratory ability. Inhibition of RAS/ERK or PI3K/AKT signaling decreased the migratory ability of these cells but did not induce E-cadherin expression. In the cells with epithelial-like morphology, treatments with phorbol-ester or tumor necrosis factor (TNF)-α resulted in translocation of membranous E-cadherin to the cytoplasm and induction of migration. E-cadherin promoter methylation status and E-cadherin expression were not affected by TNF. Demethylating agents induced apoptosis in the mesenchymal-like cells but had no effect on E-cadherin expression or on migratory ability. Together, dynamic changes in E-cadherin methylation occur during metastatic progression in thyroid cancer. Epigenetic mechanisms and TNF-inducible signaling independently contribute to the regulation of E-cadherin expression and localization. These mechanisms may play a role in the induction of EMT in primary tumors and in the conversion from the mesenchymal to the epithelial phenotype in metastases.

Status of p16&lt;SUP&gt;INK4a&lt;/SUP&gt; and E-Cadherin Gene Promoter Methylation in Moroccan Patients With Cervical Carcinoma

Aberrant methylation of tumor suppressor gene promoters has been extensively investigated in cervical cancer. Transcriptional silencing, as a main consequence of hypermethylation of CpG islands, is the predominant mechanism of p16(INK4a) and E-cadherin gene inactivation in malignant epithelial tumors. This study was conducted to evaluate the promoter methylation status of p16(INK4a) and E-cadherin genes in 22 specimens of cervical carcinomas, four cervical cancer cell lines (HeLa, SiHa, Caski, C33A), and 20 human papillomavirus negative specimens, obtained from normal cervical swabs, using the methylation-specific PCR approach. Hypermethylation of the 5' CpG island of the p16(INK4a) and E-cadherin genes were found in 13 (59.1%) and 10 (45.5%) of 22 cervical cancer samples, respectively. Furthermore, our findings did not show any correlation between promoter methylation of p16(INK4a) and E-cadherin genes and clinicopathological parameters, including HPV infection, phenotypic distribution, and stage of the disease. However, hypermethylation of E-cadherin gene promoter appears to be age related in cervical cancer, whereas the frequency of aberrant methylation of p16(INK4a) gene promoter is unchanged according to the age of patients. Thus, caution must be made to use these markers in the diagnosis of cervical cancer. However, dietary or pharmaceutical agents that can inhibit these epigenetic events may prevent or delay the development of cervical cancer.

Modest promoter methylation of E-cadherin gene in sporadic colorectal cancers: A quantitative analysis

Although E-cadherin expression is frequently reduced in colorectal cancers (CRCs), this does not appear to be due to gene mutation or allele loss. We investigated the hypothesis that promoter methylation could be responsible for suppression of E-cadherin expression in 142 pairs of sporadic CRCs and respective normal mucosae. E-cadherin expression was examined by Western blot. E-cadherin methylation at two promoter regions was quantitatively measured by methylation specific real time PCR (MethyLight). We found that E-cadherin protein levels were significantly lower in CRCs, even in Dukes' A tumors, compared to normal mucosae. Decreased E-cadherin protein expression in CRCs was an independent poor prognostic factor in multivariate disease-free survival analysis. However, the extent of DNA methylation was extremely modest at both regions of the E-cadherin promoter. There was no correlation between DNA methylation and E-cadherin protein levels in either tumors or matched normal tissues. These findings suggested that suppression of E-cadherin expression in CRCs is a significant event and is possibly involved in both carcinoma development and progression. However, our data did not support a crucial role of promoter methylation of the E-cadherin gene in the remarkable downregulation of E-cadherin expression in CRCs. Methylated E-cadherin gene as a CRC biomarker therefore needs further validation.

APC, beta-catenin, and E-cadherin and the development of recurrent endometrial carcinoma.

Endometrial carcinoma, generally, has a good prognosis. However, in some patients, the tumor appears to behave very aggressively, a course that cannot be explained with histopathological characteristics. More insight into the molecular background can be valuable to clarify these differences in tumor behavior. The three components associated with the Wnt pathway--i.e., adenomatous polyposis coli (APC), beta-catenin, and E-cadherin--were evaluated in a case-control study of 28 patients with stage-I endometrial carcinomas to determine their involvement in the development of recurrent disease. Mutation analysis of the mutation cluster region of the APC gene, determination of gene promoter methylation status of the APC-1A and E-cadherin genes, and immunohistochemical analysis of APC, E-cadherin, and beta-catenin were performed using paraffin-embedded tumor tissue. Twenty-one APC gene mutations were detected in 12 of 28 (43%) patients. Only three mutations would result in a stopcodon in the APC gene. APC gene promoter methylation was assessed in 12 of 28 (43%) patients. APC immunostaining was absent in two of 24 (8.3%) patients. The occurrence of APC mutations, APC gene promoter methylation, and APC immunostaining were not predictive for recurrence. No E-cadherin expression was observed in four of 24 patients (17%). E-cadherin gene promoter methylation could not be detected in any of the patients. The absence of E-cadherin expression was predictive for distant metastases, but not for local recurrence. Nuclear localization of beta-catenin was present in nine of 24 (38%) patients and was not predictive for recurrent disease. Involvement of epigenetic and genetic aberrations in APC and beta-catenin genes seems to be of minor importance for the development of local recurrences and distant metastases. Although the number of patients is limited, E-cadherin expression appears to be predictive for the development of distant metastases in endometrial carcinoma.

APC, β-catenin, and E-cadherin and the development of recurrent endometrial carcinoma

Endometrial carcinoma, generally, has a good prognosis. However, in some patients, the tumor appears to behave very aggressively, a course that cannot be explained with histopathological characteristics. More insight into the molecular background can be valuable to clarify these differences in tumor behavior. The three components associated with the Wnt pathway – i.e., adenomatous polyposis coli (APC), β-catenin, and E-cadherin – were evaluated in a case-control study of 28 patients with stage-I endometrial carcinomas to determine their involvement in the development of recurrent disease. Mutation analysis of the mutation cluster region of theAPCgene, determination of gene promoter methylation status of theAPC-1AandE-cadheringenes, and immunohistochemical analysis of APC, E-cadherin, and β-catenin were performed using paraffin-embedded tumor tissue. Twenty-oneAPCgene mutations were detected in 12 of 28 (43%) patients. Only three mutations would result in a stopcodon in theAPCgene.APCgene promoter methylation was assessed in 12 of 28 (43%) patients. APC immunostaining was absent in two of 24 (8.3%) patients. The occurrence ofAPCmutations,APCgene promoter methylation, and APC immunostaining were not predictive for recurrence. No E-cadherin expression was observed in four of 24 patients (17%).E-cadheringene promoter methylation could not be detected in any of the patients. The absence of E-cadherin expression was predictive for distant metastases, but not for local recurrence. Nuclear localization of β-catenin was present in nine of 24 (38%) patients and was not predictive for recurrent disease. Involvement of epigenetic and genetic aberrations inAPCand β-cateningenes seems to be of minor importance for the development of local recurrences and distant metastases. Although the number of patients is limited, E-cadherin expression appears to be predictive for the development of distant metastases in endometrial carcinoma.

Decreased expression of catenins (alpha and beta), p120 CTN, and E-cadherin cell adhesion proteins and E-cadherin gene promoter methylation in prostatic adenocarcinomas.

Catenin/E-cadherin complex proteins play an important role in cell-cell adhesion with decreased expression correlating with adverse prognostic variables in several human malignancies. Archival formalin fixed, paraffin embedded (FFPE) sections from 118 prostatic adenocarcinomas (PACs) were immunostained by an automated method (Ventana Medical Systems, Tuscon, AZ) using monoclonal antibodies to catenins alpha and beta, p120 CTN, and E-cadherin proteins. Immunoreactivity was semiquantitatively graded, and results correlated with traditional prognostic parameters. In a subset of 10 randomly selected cases, E-cadherin gene promoter methylation status was determined on FFPE tissues using sodium bisulfite/hydroquinone DNA modification and polymerase chain reaction (PCR) with methylation specific primers (CpG wiz E-cadherin methylation assay; Intergen Co., Purchase, NY). Decreased expression of alpha-catenin (17%), beta catenin (4%), p120 CTN (45%), and E-cadherin (25%) proteins was noted in PACs with downregulation of each protein correlating with high tumor grade (P = 0.01-0.0001). In addition, p120 CTN and E-cadherin expression levels correlated with pathologic stage (P = 0.05; P = 0.02), aneuploidy (P = 0.001; P = 0.0001), and alpha-catenin with aneuploidy (P = 0.0001). p120 CTN loss also correlated with preoperative serum prostate specific antigen (P = 0.05). Two of 10 cases featured no evidence of E-cadherin gene promoter methylation by PCR and both cases retained expression of E-cadherin protein on immunohistochemistry. Of the 8 cases that showed E-cadherin methylation, 5 (68%) featured loss of expression of the protein on immunohistochemistry (P = 0.11). There was no correlation between E-cadherin methylation and adverse prognostic variables. Decreased expression of catenin/E-cadherin complex cell adhesion proteins is associated with aggressive phenotype in prostatic adenocarcinoma. E-cadherin gene promote methylation is a common event in prostate carcinoma but does not appear to bear prognostic significance in the subset of cases analyzed.