Screening of pathogenic genes in Chinese patients with arrhythmogenic right ventricular cardiomyopathy / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable cardiac disease predominantly caused by mutations in desmosomal protein genes. Previous genetic analyses of the Chinese ARVC population are limited to small size and restriction to a single gene. This study was aimed to investigate the genotype in a large series of Chinese patients with ARVC through comprehensively screening nine ARVC-causing genes.</p><p><b>METHODS</b>A total of 100 unrelated ARVC patients and 300 age, gender and ethnicity matched healthy controls were genetically tested with multiplexing targeted resequencing for nine previously reported ARVC-causing genes, including plakophilin-2, desmoplakin, desmoglein-2, desmocollin-2, plakoglobin, transforming growth factor beta-3, transmembrane protein 43, desmin and Lamin A/C.</p><p><b>RESULTS</b>Fifty-nine mutations were identified in 64% of the patients, among which, 93% were located in desmosomal protein genes. Plakophilin-2 mutations accounted for 54% of the total and 58% of the desmosomal mutations, with a truncating mutation type making up about 2/3 of the plakophilin-2 mutations. Only four mutations were found in non-desmosomal genes; two in transmembrane protein 43 and two in transforming growth factor beta-3. Two of them (one of each gene) appeared as single missense mutations. No mutation was identified in desmin or Lamin A/C. Multiple mutations were found in 23% of the patients, with plakophilin-2 being found in 57% of the multi-mutation carriers.</p><p><b>CONCLUSIONS</b>Plakophilin-2 was the most common gene mutation that was identified in Chinese ARVC patients. Non-desmosomal genes should be added to desmosomal protein genes when performing molecular genetic screening in patients with suspected ARVC.</p>

Immune expression of E-cadherin and α, β and γ-Catenin adhesion molecules and prognosis for upper urinary tract urothelial carcinomas

INTRODUCTION: Cell adhesion molecules (CAM) are required for maintaining a normal epithelial phenotype, and abnormalities in CAM expression have been related to cancer progression, including bladder urothelial carcinomas. There is only one study that correlates E-cadherin and α-, β- and γ-catenin expression with prognosis of upper tract urothelial carcinomas. Our aim is to study the pattern of immune expression of these CAMs in urothelial carcinomas from the renal pelvis and ureter in patients who have been treated surgically. Our goal is to correlate these expression levels and characteristics with well-known prognostic parameters for disease-free survival. MATERIALS AND METHODS: We evaluated specimens from 20 patients with urothelial carcinomas of the renal pelvis and ureter who were treated with nephroureterectomy or ureterectomy between June 1997 and January 2007. CAM expression was evaluated by immunohistochemistry in a tissue microarray and correlated with histopathological characteristics and patient outcomes after a mean follow-up of 55 months. RESULTS: We observed a relationship between E-cadherin expression and disease recurrence. Disease recurrence occurred in 87.5% of patients with strong E-cadherin expression. Only 50.0% of patients with moderate expression and 0% of patients with weak or no expression of E-cadherin had disease recurrence (p = 0.014). There was also a difference in disease-free survival. Patients with strong E-cadherin expression had a mean disease-free survival rate of 49.1 months, compared to 83.9 months for patients with moderate expression (p = 0.011). Additionally, an absence of α-catenin expression was associated with tumors that were larger than 3 cm (p = 0.003). CONCLUSIONS: We demonstrated for the first time that immune expression of E-cadherin is related to tumor recurrence and disease-free survival rates, and the absence of α-catenin expression is related to tumor size in upper tract urothelial carcinomas.

Expression of N-terminal truncated desmoglein 3 (Delta NDg3) in epidermis and its role in keratinocyte differentiation

During a search for keratinocyte differentiation-related genes, we obtained a cDNA fragment from the 5'-untranslated region of a previously identified splicing variant of desmoglein 3 (Dg3). This transcript encodes a protein of 282 amino acids, which corresponds to the N-terminal truncated intracellular domain of Dg3 (Delta NDg3). Northern blot analysis detected a 4.6-kb transcript matching the predicted size of Delta NDg3 mRNA, and Western blot analysis with an antibody raised against the Dg3 C-terminus (H-145) detected a 31-kDa protein. Increased Delta NDg3 expression was observed in differentiating keratinocytes by RT-PCR and Western blot analysis, suggesting that Delta NDg3 is indeed a differentiation-related gene product. In immunohistochemical studies of normal and pathologic tissues, H-145 antibody detected the protein in the cytoplasm of suprabasal layer cells, whereas an antibody directed against the N-terminal region of Dg3 (AF1720) reacted with a membrane protein in the basal layer. In addition, Delta NDg3 transcript and protein were upregulated in psoriatic epidermis, and protein expression appeared to increase in epidermal tumors including Bowen's disease and squamous cell carcinoma. Moreover, overexpression of Delta NDg3 led to increased migration and weakening of cell adhesion. These results suggest that Delta NDg3 have a role in keratinocyte differentiation, and that may be related with tumorigenesis of epithelial origin.

The effect of ginsenoside Rk1 in junctional protein of severe preeclamptic placenta / 대한산부인과학회지

OBJECTIVE: To investigate the differential expression of junctional proteins in the normal and preeclamptic human placenta and the effect of ginsenoside Rk1 in junctional proteins. METHODS: Placental tissues from 10 women with severe preeclampsia and 5 normal women were collected at the time of their cesarean section. Five of 10 preeclamptic women were complicated with intrauterine growth restriction (IUGR). Immunohistochemistry and Western blotting was employed to localize junctional proteins (zo-1, occludin and plakoglobin) positive cells. The placental explant culture was performed to investigate if Rk1 can attenuate the expression of junctional proteins (zo-1, occluding and plakoglobin) induced by deferoxamine-induced hypoxia. Rk1 was treated at the day 3 and Western blot analysis was performed for protein quantification. RESULTS: There was no different expression of zo-1 and plakoglobin among all the study groups. Occludin showed negative at the endothelial cells of the terminal villi in both normal and preeclampsia groups. At the endothelial cells of the stem villi, occludin was detected in both normal and severe preeclamptic placenta with normal fetal growth. However, severe preeclampsia with IUGR were decreased expression of occludin at the endothelial cells of the stem villi. When we administered Rk1 to the placenta treated with DFO, expression of occludin was not different. CONCLUSION: The placental expression of zo-1 and plakoglobin were not different among the study groups, while that of occludin was significantly decreased at the endothelium of stem villi in severe preeclampsia with IUGR. Rk-1 showed no effect on the placental junctional proteins. These results suggest that occludin may play a role in pathophysiology of fetal growth restriction in utero.

Immunohistochemical Expression of the alpha- and gamma-Catenin in the Fetal Skin Development / 대한피부과학회지

BACKGROUND: Catenins are the associated protein with E-cadherin in the formation of adhesion complexes in normal and tumor cells related with epithelial differentiation and development of organ formation as well as in the tumor spread. The present study was aimed to find the distribution of alpha- and gamma-catenins in fetal skin development. OBJECTIVE: The purpose of this study was to observe the distribution of above two adhesion related proteins in the fetal skin during development, and to find its relationship by expression and their distribution pattern. METHODS: Skin was obtained from the scalp, chest, and sole of 21 human fetuses, ranging from 13 to 37 weeks of gestational age. Immunohistochemical staining was performed by the avidin biotin peroxidase complex method on paraffin embedded tissue using the anti-human monoclonal antibody against the human alpha- and gamma-catenins. RESULTS: alpha- and gamma-catenins were expressed strongly in basal cells of the epidermis and germ cells of skin adnexa, such as hair and eccrine glands at 13th week, followed by decreased basal cell expression. Increase in the suprabasal epithelium and differentiated adnexal epithelium, such as outer root sheath cells and eccrine ducts and glands at 18th week, and adult pattern in 23th week of gestation. Both showed similar distribution pattern in skin though gamma-catenin appeared two or three weeks later. alpha- and gamma-catenins are expressed not only in the epithelium of the skin, but also in the mesenchymal cells such as endothelial cells and fibroblasts. Though both catenins are more strongly expressed in the membrane portion, cytoplasmic expression is also noted. CONCLUSION: Both alpha- and gamma-catenin showed basically the same expression distribution pattern in the fetal skin developmental stage, suggesting that both adhesion molecules are highly related to each other in function and development of epidermis and adnexae of the skin in fetal stage.

The Correlations of E-Cadherin Catenin Complex(alpha, beta, gamma, p120cat) Expressions and Clinicopathological Findings in Tongue Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: E-cadherin and catenins (alpha, beta, gamma, p120cat) are important epithelial adhesion molecules in normal epithelial cells. Loss of E-cadherin-catenin adhesion is an important step in the progression of epithelial cancers such as tongue cancer. E-cadherin and catenins expression in carcinoma of human tongue was evaluated in relation to their clinicopathological features and prognostic values. SUBJECTS AND METHOD: Thirty-nine specimens of tongue squamous cell carcinoma were examined in this study. These patients were all treated by primary surgery without prior radiotherapy or chemotherapy. The specimens of formalin-fixed and paraffin-embedded tumor tissues were investigated by immunohistochemical analysis using E-cadherin and catenin (alpha, beta, gamma, p120cat) monoclonal antibodies. RESULTS: The expressions of E-cadherin, alpha-catenin, beta-catenin, gamma-catenin and p120cat in cell membranes were reduced or absent in 71.8%, 74.4%, 76.9%, 59.0% and 82.1% of the tumors examined, respectively. The reduced expressions of alpha-catenin and gamma-catenin in the cell membranes was cor-related with tumore differentiation (p=0.018, p=0.004, respectively). There were significant correlations between E-cadherin and expressions of the four cantenins in the cell membranes of tongue cancer. There were no correlations between beta-catenin and p120cat expression in the cytoplasm, cell nucleus and clinicopathological features. There was significant correlation between E-cadherin expression and Kaplan-Meier survival curves. CONCLUSION: These results suggest that E-cadherin and catenins (alpha, beta, gamma, p120cat) can be used as prognostic markers of human tongue squamous cell carninoma. The result of beta-catenin and p120cat absence in the nucleus suggests that Wnt/Wingless signaling or Kaiso transcription did not occur in the human tongue squamous cell carcinoma.

RImmunohistochemical Evaluation of E-cadherin/catenin (alpha-, beta-, gamma-catenin and p120CTN) Complex Expression in Early Gastric Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The significance of abnormal E-cadherin/ catenin complex expression and the correlation of each of its components in cancer remain unclear. This study aimed to characterize the clinical significance of the abnormal membrane expression of the E-cadherin/ catenin complex and the localization patterns of the beta- catenin and p120CTN in early gastric cancer. MATERIALS AND METHODS: Immunohistochemical staining for E-cadherin, alpha-, beta- and gamma-catenin and p120CTN were performed on 47 early gastric cancer specimens. The patterns of membrange expression of the E-cadherin/catenin complex, and the localization patterns of the beta-catenin and p120CTN, were semi quantitatively graded as loss, reduced, preserved or negative and positive. RESULTS: An abnormal immunoreactivity of at least one of E-cadherin/catenin complex proteins was noted in 46 (97.8%) of the 47 early gastric cancer cases. There were no significant correlations of the membrane E-cadherin/catenin expression with, either, sex, age, location, size, macroscopic type, depth of invasion or lymphovascular invasion. Abnormal expressions of membrane E-cadherin, beta-catenin and gamma-catenin were more frequent in the diffuse-type than in the intestinal type. No linear correlation was shown for the beta-catenin between the membrane and cytoplasmic expressions. Nuclear staining of the beta-catenin was observed in 5 (10.6%) cases, but nuclear staining of the p120CTN, a promotor of Kaiso transcriptional factor, was not seen. CONCLUSION: These results suggest that alterations of the E-cadherin/catenin complex may be involved in the early stages of gastric cancer. Although beta-catenin functions as a transcriptional factor, the inactivation of membrane E-cadherin does not appear to result in significant increases in the level of cytoplasmic beta-catenin. Kaiso transcriptional factor may not be involved in the early carcinogenesis of gastric cancer.

Expression of E-cadherin and alpha - , beta - , gamma - catenin proteins in endometrial carcinoma / 대한산부인과학회잡지

OBJECTIVES: E-cadherin is a transmembrane protein that is one of the key players involved in cell to cell adhesion. Loss of E-cadherin expression is suggested to promote tumor invasion and distant metastasis in tumor development. Recently, it has been proposed E-cadherin function requires its linkage to the cytoskeleton through catenins. So defects in catenins may cause defective E-cadherin function and promote tumor invasion. We intend to evaluate the expression of E-cadherin and alpha-, beta-, gamma- catenin in tissues of human endometrial carcinoma to analyze the patterns of cell adhesion molecules' expression in endometrial carcinoma and to investigate the relationship between status of cell adhesion molecules and various clinicopathological factors. MATERIALS AND METHODS: The present study investigated the immunohistochemical expression of E-cadherin and alpha-, beta-, gamma- catenin in 33 paraffin embedded formalin fixed tissues of endometrial carcinomas. RESULTS: Aberrant E-cadherin, alpha-, beta-, gamma- catenin expression was observed in 33.3(11 of 33), 27.3(9 of 33), 18.2 (6 of 33), and 51.5(17 of 33) % of the specimens, respectively. Statistically significant correlation was found between aberrant expression of E-cadherin and lymph node metastasis and cell types other than endometrioid adenocarcinoma. Aberrant pattern of gamma- catenin expression also correlated with deep myometrial invasion. But alpha-, beta- catenin expression were not correlated with any clinicopathological parameters. Using Kaplan-Meier curves, abnormal expression of E-cadherin correlated closely with poor survival (p<0.05). CONCLUSION: We revealed aberrant expression of these cell adhesion molecules in part of patients with endometrial carcinoma. Aberrant expression of E-cadherin was correlated with lymph node metastasis and cell types other than endometrioid adenocarcinoma and aberrant expression of gamma-catenin was related with deep myometrial invasion.

Effect of Hepatocyte Growth Factor on the Expression of E-cadherin in Gastric Carcinoma Cell Lines / 대한암학회지

PURPOSE: Previously, we reported that the expression of E-cadherin was significantly decreased according to the increase of the level of hepatocyte growth factor (HGF) in gastric cancer tissue. In this work, the effect of HGF on the cell-cell adhesion and intracellular distribution of E-cadherin in the gastric carcinoma cell lines were studied. MATERIALS AND METHODS: Western blot analysis was performed to confirm the presence or abscence of c-Met and E-cadherin in SNU-1, 5, and 16 cells. Tyrosine phosphorylation of c-Met, E-cadherin, alpha-, beta-, gamma-catenins was checked by immunoprecipitation. The morphologic changes induced by HGF were studied with immunocytochemical staining. Functional proportion of E-cadherin was estimated by cell fractionation. The effect of HGF on cell proliferation and invasion was also assessed. RESULTS: Among SNU-1, 5, and 16 cell lines, only SNU-16 cells expressed both E-cadherin and c-Met. A morphological change from epithelial shape to fibroblastic one was observed in the SNU-16 cells after treatment with HGF. In addition, E-cadherin expression of the SNU-16 cells was shifted from the membrane and to the cytoplasm, and the functional fraction of E-cadherin was decreased in the SNU-16 cells treated with HGF. On the other hand, HGF increased the proliferation and invasion of the SNU-16 cells. CONCLUSION: These results suggest that HGF may regulate cell adhesion in gastric carcinomas via the cellular redistribution and functional change of E-cadherin.

The expression and tyrosine phosphorylation of E-cadherin, beta-, gamma-catenin and EGFR after treatment of EGF and TGF-alpha in Cervical Cancer Cell Lines / 대한부인종양콜포스코피학회잡지

OBJECTIVES: Cadherin/catenin adhesion complex is fundamentally involved in epithelial cancer invasion and metastasis. E-cadherin and EGFR colocalize on the basolateral membrane of epithelial cell and EGF down-regulate E-cadherin expression. In the invasion and metastasis of cancer, E-cadherin expression is decreased and growth factors receptor is overexpressed. The present study was aimed to find the role of E-cadherin, beta-and gamma-catenin, growth factors and its receptors in cervical cancer cell lines. METHODS: The cervical cancer cell cultures were treated with different time duration of EGF 30 ng/ml and TGF-a 10 ng/ml(0, 10 min, 20 min, 30 min, 1 hr, 2 hr, 4 hr, 8 hr, 24 hr). The change in cancer cell morphology and the changes in E-cadherin, beta- and gamma-catenin, EGFR and activated EGFR expression were studied with a western blot analysis and an immunoprecipitation. RESULTS: Through a western blot analysis, E-cadherin 120 kDa band and EGFR 170 kDa band were expressed in CaSki, HT-3 and ME-180 cell line, which showed epithelial contact growth. 1n these 3 cell lines, expression of E-cadherin did not decrease with time dependent manner. after the treatment of EGF and TGF- alpha. The expression of EGFR decreased and activated EGFR expression increased in 30 minutes to 1 hour but decreased subsequently. When the cells treated with EGF, there were no change in beta-and gamma-catenin expression with there dependent manner. The tyrosine phosphorylation of beta-and gamma-catenin increased in 30 minutes to 1 hour but decreased subsequently with activated EGFR. CONCLUSION: This study showed that an activated EGFR which has involved with tyrosine phosphorylation of beta- and gamma-catenin influenced by growth factors rather than expression of E-cadherin, has a role in the invasion and metastasis of the cervical cancer.