人DNA MTase反义基因转染诱导E-Cadherin基因启动子区域去甲基化

目的：观察人DNA MTase反义基因转染对肝癌细胞系SMMC－7721E－Cadherin基因启动子区域甲基化状态的影响。方法：采用脂质体法将已构建的包含正，反义DNA MTase基因片段的真核表达载体转染入肝癌细胞系SMMC－7721；用甲基化特异的PCR法检测E－Cadherin基因启动子区域甲基化状态的改变，结果：PCR法扩增外源性NeoR基因证实用脂体法成功将重组载体转染入细胞，甲基化特异的PCR法检测显示转染反义DNA MTase基因片段的SMMC－7721细胞中的E－Cadherin基因启动子区域呈现去甲基化状态。结论：人DNA MTase反义基因片段可诱导E－Cadherin基因启动子区域去甲基化，实验结果有助于进一步了解DNA MTase在肝癌发展中的作用。     

An Ileal Endometrioma: Of Carcinoids and Cadherin

A 38-year-old woman with history of prior adrenalectomy for Cushing’s syndrome presented with intermittent right lower quadrant (RLQ) abdominal pain, nausea, bloating, and non-bloody diarrhea for 2 months. Symptoms were not related to her menstrual periods. Examination revealed only an ill-defined mass in the RLQ. Investigations for infectious causes, inflammatory bowel disease, and carcinoid tumor were negative. Computed tomography (CT) demonstrated a terminal ileal mass with mesenteric stranding and dilatation of the proximal bowel. At laparotomy, a fibrotic, terminal ileal mass with matted adhesions involving the mesentery and retroperitoneum was resected. Histopathological examination identified multiple foci of endometriosis extending from the serosal surface into the mucosa of the terminal ileum. Immunostaining revealed E- and P-cadherin, but not N-cadherin immunopositivity. Mucosal involvement without cyclical menstrual symptoms and intestinal obstruction is an unusual presentation of intestinal endometriosis. Although the mechanism of endometriosis is not clear, the role of cell adhesion molecules such as cadherins has received attention. Increased expression of E- and P-cadherin and decreased N-cadherin expression in our patient demonstrates differential expression of these cadherins in endometriotic tissue. Future studies may investigate patterns of differential expression of these cadherins in a series of cases to elucidate the mechanisms of migration of endometriotic tissue.     

Association between cadherin-17 expression and pathological characteristics of gastric cancer:A meta-analysis

AIM: To construct a meta-analysis in order to examine the relationship between cadherin-17(CDH17) andgastric cancer(GC). METHODS: Related articles were selected by searching the following English or Chinese electronic databases: CINAHL, MEDLINE, Science Citation Index, the Chinese Journal Full-Text, and the Weipu Journal. NewcastleOttawa Scale(NOS) criteria were used to ensure consistency in reviewing and reporting results. Statistical analyses were conducted with Version 12.0 STATA statistical software.RESULTS: Ultimately, 11 articles, with a total of 2,120 GC patients, were found to be eligible for study inclusion. In comparisons of GC patients by TNM stage(Ⅲ-Ⅳ vs ?Ⅰ-Ⅱ: OR = 2.35, 95%CI: 1.15-4.825, P = 0.019), histologic grade(3-4 vs 1-2: OR = 3.48, 95%CI: 1.36-8.92, P = 0.009), invasion grade(T3-4 vs T1-2: OR = 2.86; 95%CI: 1.69-4.83; P = 0.000), and lymph node metastasis(positive vs negative: OR = 2.64; 95%CI: 1.33-5.27; P = 0.006), it was found that CDH17 showed more positive expressions in each of the more severe cases. Country-stratified analyses from all four experimental subgroups showed that high CDH17 expression levels may be related to GC among Chinese and Korean populations(all P < 0.05), with the exception of the invasion grade T3-4 vs T1-2 comparison, where the relation only held among the Chinese population(OR = 2.86, 95%CI: 1.69-4.83, P = 0.000). CONCLUSION: Collectively, the data reflects the capacity of CDH17 in tumor proliferation and metastasis among GC patients.     

β-tubulin-Ⅲ、E-cadherin和α-catenin在乳腺癌及癌前病变中的表达及诊断意义

目的探讨乳腺癌前病变及浸润性癌中β-tubulin-Ⅲ、E-cadherin和α-catenin的表达及诊断意义。 方法采用免疫组织化学UltraSensitiveTM S-P法检测20例乳腺非典型导管上皮增生(ADH)、60例乳腺导管原位癌(DCIS)和90例浸润性乳腺癌(IDC)中的β-tubulin-Ⅲ、E-cadherin和α-catenin的表达,以30例正常乳腺组织作对照。 结果β-tubulin-Ⅲ微管蛋白的表达：(1)β-tubulin-Ⅲ微管蛋白在正常对照组、ADH、DCIS和IDC组中表达率为22.0%,55.0%,71.7%,84.4%,4组间差异有统计学意义(χ²＝22.298,P<0.05),两两组间比较,导管原位癌组、浸润性导管癌组与非典型导管增生组、正常对照组比较均差异有统计学意义(χ²＝39.525,22.474,6.551,P<0.05)。2. E-cadherin和α-catenin的表达：在正常对照组、ADH、DCIS和IDC组中,E-cadherin的表达率分别为100%、75.0%、68.3%和41.1%,α-catenin的表达率为100.0%、80.0%、73.3%和56.7%,在四组中E-cadherin和α-catenin的表达差异有统计学意义(χ²＝18.65,10.97,P<0.05)。 结论乳腺癌前病变中β-tubulin-Ⅲ过表达,可能是乳腺癌形成的早期事件;E-cadherin和α-catenin在乳腺细胞过度增殖、恶性转化的过程中起重要作用,可作为判断组织病变程度及侵袭能力强弱的因素,β-tubulin-Ⅲ微管蛋白及E-cadherin、α-catenin有可能成为诊断和评估乳腺癌变和治疗的指标。     

Role of androgens and glucocorticoids in the regulation of diazepam-binding inhibitor mRNA levels in male mouse hypothalamus

Receptor protein tyrosine phosphatase rho (RPTPrho/PTPRT) is a transmembrane protein that is highly expressed in the developing and adult central nervous system. It is a member of the RPTP R2B subfamily, which includes PTPkappa, PTPmu and PCP-2. Glutathione-S-transferase (GST) pulldown assays were used to show that RPTPrho interacts with several adherens junctional proteins in brain, including E-cadherin, N-cadherin, VE-cadherin (cadherin-5), desmoglein, alpha, beta and gamma catenin, p120(ctn) and alpha-actinin. With the exception of E-cadherin and alpha-actinin, binding was considerably reduced at high sodium concentrations. Furthermore, immunoprecipitation phosphatase assays indicated that E-cadherin, and to a far lesser extent p120(ctn), were tyrosine dephosphorylated by a recombinant RPTPrho intracellular fragment, and thus, were likely to be primary substrates for RPTPrho. The interaction of RPTPrho with adherens junctional components suggests that this phosphatase may transduce extracellular signals to the actin cytoskeleton and thereby play a role in regulating cadherin-mediated cell adhesion in the central nervous system.     

Microarray comparative genomic hybridization analysis of tubular breast carcinoma shows recurrent loss of the CDH13 locus on 16q

Tubular breast carcinoma is a highly differentiated carcinoma with an excellent prognosis. Distinct genetic alterations in tubular breast carcinoma cells have been described, especially broad genetic losses on the q-arm of chromosome 16. These are more common in lobular breast carcinoma and low-grade ductal carcinoma in situ than in ductal breast carcinoma and high-grade ductal carcinoma in situ. To further delineate the molecular changes involved in tubular breast carcinoma more precisely, we examined 23 formalin-fixed and paraffin wax-embedded tissue samples (21 of tubular breast carcinoma and 2 of nonneoplastic breast epithelium) by microarray-based comparative genomic hybridization focusing on 287 genomic target clones of oncogenes and tumor suppressor genes. The results obtained from all nonneoplastic tissue samples of breast epithelium indicate no DNA copy number changes. In the tubular breast carcinoma samples, the highest frequencies for DNA sequence copy number losses were detected for CDH13 (in 86% of the samples) and MSH2, KCNK12 (in 52% of the samples). The highest frequencies of DNA sequence copy number gains were detected for HRAS and D13S319XYZ (each in 62% of the samples). Using principal component analysis, 3 subgroups of tubular breast carcinomas showing relative genetic changes were identified. For validation, the most frequent DNA copy number loss for CDH13 (18/21) was confirmed using fluorescence in situ hybridization in 4 of 5 tubular breast carcinomas analyzed. The newly identified genes with considerable copy number changes may include so far unknown candidate genes for the development and progression of tubular breast carcinoma, such as CDH13. The study provides the starting point for further delineating their detailed influence on the pathogenesis of tubular breast carcinoma.     

钙黏素23基因多态性与噪声性听力损失易感性关系研究

目的探讨钙黏素23(CDH23)基因多态性与噪声性听力损失易感性关系。方法采用病例对照研究方法对254名接触噪声工人进行研究,聚合酶链反应-限制性片断长度多态性方法检测CDH23基因单核苷酸多态性位点rs1227049和rs1227051的多态性。结果rs1227049位点在听损组CC、CG和GG基因型频率分别为39.4%、15.0%和45.6%,等位基因C和G的频率分别为46.9%和53.1%;对照组3种基因型的频率分别为51.2%、19.7%和29.1%,等位基因C和G的频率分别为60.9%和39.1%。rs1227051位点在听损组TT、CT和CC基因型频率分别为82.7%、17.3%和0,等位基因T和C的频率分别为91.3%和8.7%。对照组3种基因型的频率分别为89.0%、11.0%和0,等位基因T和C的频率分别为87.0%和13.0%。两位点的基因型分布及其等位基因频率在听损组和对照组之间差异均无统计学意义(P>0.05)。采用多因素Logistic回归分析对个体间年龄、工龄和累积噪声暴露量等因素进行校正后,也未发现两个单核苷酸位点任一基因型的改变会引起噪声性听力损失的危险度有显著性提高(P>0.05)。结论本研究还不能认为CDH23基因rs1227049和rs1227051两个单核苷酸多态性位点是噪声性听力损失易感性的危险因素。     

An in vitro embryotoxicity assay based on the disturbance of the differentiation of murine embryonic stem cells into endothelial cells. II. Testing of compounds

The embryonic stem cell test (EST) developed by Spielmann et al. [Spielmann, H., Pohl, I., Doering, B., Liebsch, M., Moldenhauer, F., 1997. The embryonic stem cell test, an in vitro embryotoxicity test using two permanent mouse cell lines: 3T3 fibroblasts and embryonic stem cells. In Vitro. Toxicol. 10, 119–127] is currently the most promising in vitro assay to predict the embryotoxic potential of compounds. In this assay the disturbance of the differentiation of embryonic stem (ES) cells into contracting cardiomyocytes by test compounds as well as the direct cytotoxicity of the test compounds on ES cells and 3T3 fibroblasts is analyzed. On the basis of these results and by applying a biostatistical prediction model (PM) [Genschow, E., Scholz, G., Brown, N., Piersma, A., Brady, M., Clemann, N., Huuskonen, H., Paillard, F., Bremer, S., Becker, K., Spielmann, H., 2000. Development of prediction models for three in vitro embryotoxicity tests in an ECVAM validation study. In Vitr. Mol. Toxicol. 13, 51–66; Genschow, E., Spielmann, H., Scholz, G., Pohl, I., Seiler, A., Clemann, N., Bremer, S., Becker, K., 2004. Validation of the embryonic stem cell test in the international ECVAM validation study on three in vitro embryotoxicity tests. Altern. Lab. Anim. 32, 209–244; Genschow, E., Spielmann, H., Scholz, G., Seiler, A., Brown, N., Piersma, A., Brady, M., Clemann, N., Huuskonen, H., Paillard, F., Bremer, S., Becker, K., 2002. The ECVAM international validation study on in vitro embryotoxicity tests: results of the definitive phase and evaluation of prediction models. European Centre for the Validation of Alternative Methods. Altern. Lab. Anim. 30, 151–176] test compounds can be classified as non-embryotoxic, weakly or strongly embryotoxic. In order to introduce a further endpoint into the EST, the disturbance of vasculogenesis and/or angiogenesis, a protocol to differentiate ES cells into endothelial cells, was established in the accompanying paper. PECAM-1 and VE-Cadherin gene expressions, quantified by real-time TaqMan^® PCR, were shown to be appropriate molecular markers for the differentiation of ES cells into endothelial cells. In the present study, the disturbance of the differentiation of ES cells into endothelial cells (i.e. the reduction in the expression of PECAM-1 and VE-Cadherin) by six test compounds with known embryotoxic potential was investigated: all-trans-retinoic acid (RA) and 5-fluorouracil (5-FU) are strongly embryotoxic, diphenylhydantoin (DPH) and valproic acid (Val) are weakly embryotoxic and saccharin (Sacch) and penicillin G (Pen G) are non-embryotoxic. In a first step the concentration of the test compound resulting in a 50% inhibition of PECAM-1 and VE-Cadherin gene expression and the concentration leading to a 50% decrease in the viability of ES cells and 3T3 fibroblasts were determined. In a second step and in a first attempt to assess the predictive potential of the newly developed test system the concentration values obtained were applied in the PM of the established EST to classify the selected test compounds. All six test compounds were correctly classified (i.e. the data obtained in vitro correlated with their known embryotoxic potential in vivo). Taken together it can be concluded that the disturbance of the differentiation of murine ES cells into endothelial cells represents a very promising new endpoint in a broadened EST with PECAM-1 and VE-Cadherin as specific differentiation marker genes.