OBJECTIVETo investigate the protein expression, methylation promoter, somatic and germ-line mutations of E-cadherin gene (CDH1) in hereditary gastric cancer in China and to investigate its possible roles.

METHODSEight probands diagnosed with ICG-HGC criterion were enrolled in our database from June 1994 to October 2007. Tumor tissues were detected for CDH1 expression by using immunohistochemistry (IHC) methods. CDH1 DNA sequencing was performed for all its 16 exons both in tumor and normal tissues of the same patients to detect somatic and germ-line mutations. Methylation promoter study was performed by using specific primers and polymerase chain reaction (PCR) methods.

RESULTSIHC analysis confirmed that the CDH1 expression was negative in 7 probands and downregulated in the other on proband. Six mutations in five probands were found with DNA sequencing: two silent mutations and four missense mutations. All six mutations were absent in normal tissues, thereby excluded its presence in germ-line cells. Both DNA missense mutations and gene silencing through promoter methylation was found in 4 probands. Two probands has only promoter methylation and one proband had only silent mutation. No DNA missense mutations or promoter methylation was found in one proband.

CONCLUSIONSCDH1 gene germ-line mutations are relatively rare in hereditary gastric cancer in China, and whereas CDH1 somatic mutations and promoter methylation synergistically induce CDH1 downregulation in these patients.

Cadherins ; genetics ; DNA Methylation ; DNA Mutational Analysis ; Germ-Line Mutation ; Humans ; Promoter Regions, Genetic ; genetics ; Stomach Neoplasms ; genetics

OBJECTIVETo study the mechanism of invasion and metastasis in early nasopharyngeal carcinoma (NPC) in relation to E-cadherin promoter methylation and mutation in exon 3 of beta-catenin.

METHODSMethylation of E-cadherin promoter, mutation in exon 3 of beta-catenin and differential expression of beta-catenin in the primary lesion of 21 NPC and the metastatic lymph node of 21 NPC were investigated by DNA Methylation-Specific PCR, direct sequencing and immunohistochemical method.

RESULTSMethylation on E-cadherin promoter was showed in 23.8% (5/21) primary lesions and 61.9% (13/21) metastatic lymph nodes (P < 0.01). Mutation in exon 3 of beta-catenin was showed in 3 of 42 tissues: codon 37 (TCT-->GCT), codon 41 (ACC-->GCC) and codon 47 (AGT-->ACT). However, there was no relation between these mutations and invasion or metastasis (P > 0.05). High beta-catenin expression on the membrane without nuclear expression was observed in 42 tissues (P > 0.05).

CONCLUSION1. In NPC, methylation of promoter is a major cause of down-regulation of E-cadherin which may finally lead to detachment and metastasis of neoplastic cells, 2. Mutation in exon 3 of beta-catenin is a rare event in NPC. It may be an early event in the carcinogenesis of NPC but have no significant role in invasion and metastasis and 3. High expression of beta-catenin, as one of NPC characteristics, is not a key factor for invasion or metastasis.

Adult ; Aged ; Cadherins ; genetics ; DNA Methylation ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Mutation ; Nasopharyngeal Neoplasms ; genetics ; pathology ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Promoter Regions, Genetic ; beta Catenin ; analysis ; genetics

OBJECTIVETo investigate the protein and mRNA expression of E-cadherin and beta-catenin in nonsmall cell lung carcinoma (NSCLC) and to find their correlation with histological type, differentiation, metastasis and prognosis.

METHODSHigh sensitive S-P immunohistochemical method and in situ hibridization were used to detect the protein and mRNA expression of E-cadherin and beta-catenin.

RESULTSImmunohistochemistry revealed that among the 101 cases, the positive rates of E-cadherin and beta-catenin were 68.3% and 81.2% respectively. The abnormal expression rates of these two proteins were 61.4% and 64.4% respectively. There was no significant relationship between E-cadherin and beta-catenin staining and histological type of the tumor (P > 0.05). However, there was a statistically significant difference between well and moderately differentiated cells and poorly differentiated cells (P < 0.05). In cases with lymphatic metastasis, the abnormal expression rates of E-cadherin and beta-catenin were significantly higher than those in nonmetastatic cases (P < 0.05). The mean survival time in cases with abnormal E-cadherin and beta-catenin expression were significantly shorter than that in cases with the expression grading (+ +) approximately (+ + +). In situ hybridization showed that in NSCLC, the positive rate of E-cadherin and beta-catenin mRNA was 38.9% and 47.2% respectively. Their concordant rates with (+ +) approximately (+ + +) protein expression were 78.6% and 82.4%, respectively.

CONCLUSIONSThe concordant rate of E-cadherin and beta-catenin mRNA and protein expression was relatively high. They can be used as markers of prognosis of NSCLC in clinical practice.

Adult ; Aged ; Cadherins ; analysis ; genetics ; Carcinoma, Non-Small-Cell Lung ; chemistry ; mortality ; Cytoskeletal Proteins ; analysis ; genetics ; Female ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Lung Neoplasms ; chemistry ; mortality ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; analysis ; Survival Rate ; Trans-Activators ; analysis ; genetics ; beta Catenin

BACKGROUNDThis study was designed to detect methylation of E-cadherin gene promoter and gene mutation of beta-catenin in exon 3 and their expression of protein and mRNA in primary tumor and lymph node metastatic tumor of nasopharyngeal carcinoma (NPC), and investigate the mechanism of invasion and metastasis of neoplastic cells in NPC.

METHODSFourty-two fresh biopsy samples were taken from untreated NPC patients at the Affiliated Hospital of Sun Yat-sen Medical College, Sun Yat-sen University, Guangzhou, China during the period of 1999-2002. Among them 21 were taken from primary tumors and the other 21 from lymph node metastatic tumors. The gene promoter methylation of E-cadherin was detected by methylation-specific PCR (MSP). The mutation in exon 3 of beta-catenin was detected by direct sequencing analysis. RT-PCR, Western blot and immunohistochemical staining were used to detect the mRNA and protein expression patterns in both primary and metastatic tumors of NPC.

RESULTSDown-regulated expression of E-cadherin in metastatic tumor was compared with that in primary tumor. Reduced expression of E-cadherin was found to be correlated with lymph node metastatic tumor of NPC (P = 0.004); but there was no obvious correlation between primary and metastatic tumors in the expression of beta-catenin (P = 0.698). The mRNA expression level of E-cadherin in metastatic tumors decreased significantly compared with that in primary tumors. However, little change was observed in the mRNA level of beta-catenin in different tumor tissues. Only 4 samples (19.1%) displayed gene promoter methylation of E-cadherin in primary tumor and 10 samples (47.6%) showed methylated form of E-cadherin. The gene promoter methylation of E-cadherin was more common in metastatic tumor than in primary tumor of NPC (P = 0.024). Only 2 (4.76%) of the 42 samples showed mutations in exon 3 of beta-catenin at 41 (T41A, ACC-->GCC) and codon 47 (S47T, AGT-->ACT). The cytoplasmic and nuclear expression of beta-catenin in tumor was not found in any samples of NPC.

CONCLUSIONSThe results suggest that the downregulation of E-cadherin results from the gene promoter aberrant methylation of E-cadherin and that the methylation of E-cadherin plays an important role in invasion and metastasis of tumor cells in NPC. However, beta-catenin mutation is an infrequent event in NPC, and beta-catenin is not a critical factor influencing the invasion and metastasis of tumor cells in NPC.

Adult ; Aged ; Blotting, Western ; Cadherins ; analysis ; genetics ; Cytoskeletal Proteins ; analysis ; genetics ; DNA Methylation ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Mutation ; Nasopharyngeal Neoplasms ; chemistry ; genetics ; pathology ; Neoplasm Metastasis ; Promoter Regions, Genetic ; Trans-Activators ; analysis ; genetics ; beta Catenin

OBJECTIVETo investigate the molecular mechanism of action of BET bromodomain inhibitor JQ1 in treating airway remodeling in asthmatic mice.

METHODSA total of 24 mice were randomly divided into control group, ovalbumin (OVA)-induced asthma group (OVA group), and JQ1 intervention group (JQ1+OVA group), with 8 mice in each group. OVA sensitization/challenge was performed to establish a mouse model of asthma. At 1 hour before challenge, the mice in the JQ1+OVA group were given intraperitoneal injection of JQ1 solution (50 μg/g). Bronchoalveolar lavage fluid (BALF) and lung tissue samples were collected at 24 hours after the last challenge, and the total number of cells and percentage of eosinophils in BALF were calculated. Pathological staining was performed to observe histopathological changes in lung tissue. RT-PCR and Western blot were used to measure the mRNA and protein expression of E-cadherin and vimentin during epithelial-mesenchymal transition (EMT).

RESULTSCompared with the control group, the OVA group had marked infiltration of inflammatory cells in the airway, thickening of the airway wall, increased secretion of mucus, and increases in the total number of cells and percentage of eosinophils in BALF (P<0.01). Compared with the OVA group, the JQ1+OVA group had significantly alleviated airway inflammatory response and significant reductions in the total number of cells and percentage of eosinophils in BALF (P<0.01). Compared with the control group, the OVA group had significant reductions in the mRNA and protein expression of E-cadherin and significant increases in the mRNA and protein expression of vimentin (P<0.01); compared with the OVA group, the JQ1+OVA group had significant increases in the mRNA and protein expression of E-cadherin and significant reductions in the mRNA and protein expression of vimentin (P<0.01); there were no significant differences in these indices between the JQ1+OVA group and the control group (P>0.05).

CONCLUSIONSMice with OVA-induced asthma have airway remodeling during EMT. BET bromodomain inhibitor JQ1 can reduce airway inflammation, inhibit EMT, and alleviate airway remodeling, which provides a new direction for the treatment of asthma.

Airway Remodeling ; drug effects ; Animals ; Asthma ; drug therapy ; Azepines ; pharmacology ; Cadherins ; analysis ; genetics ; Epithelial-Mesenchymal Transition ; Female ; Mice ; Nuclear Proteins ; antagonists & inhibitors ; Ovalbumin ; immunology ; RNA, Messenger ; analysis ; Transcription Factors ; antagonists & inhibitors ; Triazoles ; pharmacology ; Vimentin ; analysis ; genetics

OBJECTIVETo explore the expression and significance of E-cadherin (E-cad) and beta-catenin (beta-cat) in synovial sarcoma.

METHODSExpression of E-cad and beta-cat in 72 cases of synovial sarcoma were detected by tissue microarray technique and immunohistochemistry. The relationships between E-cad and beta-cat expression and clinicopathological data and survival rate were analyzed.

RESULTS(1) 95.1% of dots on the tissue microarrays were observable morphologically. The background was clear and the contrast was vivid after immunohistochemistry. (2) The expression of E-cad was reduced in 56 patients (77.8%) and that of beta-cat was reduced in 51 patients (70.8%). (3) In patients with synovial sarcoma of monophasic fibrous type, grade III, and in patients with recurrence or metastasis, CK-negative and EMA-negative the rates of reduced expression of E-cad and beta-cat were significantly higher than those with primary sarcoma of biphasic type, grade II, CK-positive and EMA positive (P < 0.05 for all). (4) The survival of synovial sarcoma patients with E-cad and beta-cat expressions preserved was significantly better than those with reduced expressions (P = 0.012, P = 0.047).

CONCLUSIONThe expression of E-cad and beta-cat is correlated with cell differentiation. Reduced expression of E-cad and beta-cat may indicate a high potential of recurrence or metastasis and poor prognosis. Tissue microarray technique is applicable for retrospective studies of large sample size.

Adult ; Cadherins ; biosynthesis ; genetics ; Extremities ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Metastasis ; Prognosis ; Sarcoma, Synovial ; metabolism ; pathology ; Soft Tissue Neoplasms ; metabolism ; pathology ; Tissue Array Analysis ; beta Catenin ; biosynthesis

OBJECTIVETo explore the correlation between the expressions of galectin-3 and E-cadherin and lymph node metastasis of colon cancer.

METHODSImmunohistochemistry was employed to examine the expressions of E-cadherin and galectin-3 in 37 colon cancer samples, among which 21 samples underwent RT-PCR for E-cadherin and galectin-3 mRNA expressions. The correlation of E-cadherin and galectin-3 expressions with lymph node metastasis of the tumor was analyzed.

RESULTSThe positivity rate of galectin-3 expression was 83.8% (31/37) in these samples. Of the tumor cases with lymph node metastasis, 94.7% (18/19) of the tumors were positive for galectin-3 expression, a rate significantly higher than that in non-metastatic cases. The positivity rate of E-cadherin expression was 59.5% (22/37) in the total cases, and 47.4% (9/19) in the metastatic cases, significantly lower than that in the non-metastatic cases.

CONCLUSIONGalectin-3 and E-cadherin expressions are associated with lymph node metastasis of colon cancer and may serve as potential prognostic indicators for colon cancer patients.

Adult ; Aged ; Aged, 80 and over ; Biomarkers, Tumor ; analysis ; genetics ; Cadherins ; genetics ; Colonic Neoplasms ; genetics ; pathology ; Female ; Galectin 3 ; genetics ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Middle Aged ; Prognosis ; Reverse Transcriptase Polymerase Chain Reaction ; Young Adult

OBJECTIVETo quantitatively detect the methylation of E-cadherin gene 5'-CpG islands in acute leukemia by microarray-based DNA analysis and to briefly discuss the role of microarry for detection of methylation in tumors.

METHODSBisulfite-modified DNA was used as a template for PCR amplification, resulting in conversion of unmethylated cytosine, but not methylated cytosine, into thymine within CpG islands of interest. Five sets of oligonucleotide probes were designed to fabricate a DNA microarray to detect the methylation changes of E-cadherin gene CpG islands in acute leukemia. By drawing a standard curve to assess the levels of changes in methylation detected in the examined samples.

RESULTSMicroarray assay was successfully used to quantitatively detect methylation changes of E-cadherin gene in 5 acute leukemia samples. Varying degree of methylation was detected in five regions and the hypermethylation region was the same. The result was validated by gene sequencing.

CONCLUSIONMicroarray assay may be applied as an useful tool for mapping methylation changes in multiple CpG loci and for leukemia research. It is more time-saving and labor-saving than gene sequencing and can be used to quantitatively detect changes in methylation with high throughput.

Base Sequence ; Cadherins ; genetics ; CpG Islands ; genetics ; DNA Methylation ; Humans ; Leukemia, Myeloid, Acute ; genetics ; Molecular Sequence Data ; Oligonucleotide Array Sequence Analysis ; methods ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Promoter Regions, Genetic

PURPOSE: The nasal mucosa is the first site to encounter pathogens, and it forms continuous barriers to various stimuli. This barrier function is very important in the innate defense mechanism. Additionally, inflammation of the nasal sinus is known to be a hypoxic condition. Here, we studied the effect of hypoxia on barrier function in normal human nasal epithelial (NHNE) cells. MATERIALS AND METHODS: The expression levels of various junction complex proteins were assessed in hypoxia-stimulated NHNE cells and human nasal mucosal tissues. We performed real-time polymerase chain reaction analysis, western blotting, and immunofluorescence assays to examine differences in the mRNA and protein expression of ZO-1, a tight junction protein, and E-cadherin in NHNE cells. Moreover, we evaluated the trans-epithelial resistance (TER) of NHNE cells under hypoxic conditions to check for changes in permeability. The expression of ZO-1 and E-cadherin was measured in human nasal mucosa samples by western blotting. RESULTS: Hypoxia time-dependently decreased the expression of ZO-1 and E-cadherin at the gene and protein levels. In addition, hypoxia decreased the TER of NHNE cells, which indicates increased permeability. Human nasal mucosa samples, which are supposed to be hypoxic, showed significantly decreased levels of ZO-1 and E-cadherin expression compared with control. CONCLUSION: Our results demonstrate that hypoxia altered the expression of junction complex molecules and increased epithelial permeability in human nasal epithelia. This suggests that hypoxia causes barrier dysfunction. Furthermore, it may be associated with innate immune dysfunction after encountering pathogens.
Anoxia/etiology/*metabolism ; Blotting, Western ; Cadherins/*analysis/genetics ; Epithelium/chemistry/pathology ; Humans ; Membrane Proteins/*analysis ; Nasal Mucosa/*chemistry/pathology/*secretion ; Permeability/*radiation effects ; RNA, Messenger/genetics/metabolism ; Real-Time Polymerase Chain Reaction ; Tight Junctions/*metabolism ; Zonula Occludens-1 Protein

Gastric cancer (GC) is one of the most common cancers with high morbidity and mortality. Familial GC is seen in 10% of cases, and approximately 3% of familial GC cases arise owing to hereditary diffuse gastric cancer (HDGC). CDH1, which encodes the protein E-cadherin, is the only gene whose mutations are associated with HDGC. Screening for the familial GC-predisposing gene has been neglected in high-risk countries such as Korea, China, and Japan, where all the cases have been attributed to Helicobacter pylori or other carcinogens. Screening for the GC-causing CDH1 mutation may provide valuable information for genetic counseling, testing, and risk-reduction management for the as-yet unaffected family members. An asymptomatic 44-yr-old Korean male visited our genetic clinic for consultation owing to his family history of GC. Eventually, c.1018A>G in CDH1, a known disease-causing mutation, was found. As of the publication time, the individual is alive without the evidence of GC, and is on surveillance. To our knowledge, this is the first Korean case of presymptomatic detection of CDH1 mutation, and it highlights the importance of genetic screening for individuals with a family history of GC, especially in high-risk geographical areas.
Adult ; Asian Continental Ancestry Group/*genetics ; Cadherins/*genetics ; Exons ; Genetic Counseling ; Genetic Predisposition to Disease ; Genetic Testing ; Germ-Line Mutation ; Heterozygote ; Humans ; Male ; Pedigree ; Republic of Korea ; Sequence Analysis, DNA ; Stomach Neoplasms/*genetics/pathology