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91.
Yoshiki Asayama Ken‐ichi Taguchi Shin‐ichi Aishima Hidehiro Nishi Kouji Masuda Masazumi Tsuneyoshi 《Liver international》2002,22(1):43-50
Abstract: Background/Aim: To investigate the mode of progression of combined hepatocellular carcinoma and cholangiocarcinoma (cHCC‐CC). Methods: An immunohistochemical study for E‐cadherin (ECD) and alpha‐ and beta‐catenins was performed on 29 cases of cHCC‐CC. Results: Reduced expression of ECD was significantly correlated with the tumour grade of the hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) components, intrahepatic metastasis (IM) of HCC, IM of CC, and vascular invasion of CC (p < 0.05, respectively). There was a significant relationship between the reduced expression of beta‐catenin and the tumour grade of HCC components (p < 0.05). Cases showing concurrent intrahepatic metastasis composed of HCC, CC, or both, numbered 6, 5, and 2, respectively. The expression patterns of ECD and beta‐catenin of IM were similar to those of primary lesion in most cases. On the other hand, expression of ECD and beta‐catenin of IM of HCC component were preserved, even though those of the primary sites were reduced in two cases and one case, respectively. ECD and beta‐catenin were significantly correlated with tumour differentiation and tumour progression. Conclusions: Preserved or recovered ECD and beta‐catenin expression may be of beneficial effect for re‐establishing the tissue architecture at the metastatic site. 相似文献
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《Hemoglobin》2013,37(3):197-204
Hb E [β26(B8)Glu→Lys], is the most common abnormal hemoglobin (Hb) in Southeast Asian populations. The hitherto highest frequencies of the Hb E gene (HBB*E) in large population samples, ~?0.3, were observed in the southern part of northeastern Thailand. The finding of even higher frequencies in a small, isolated Austroasiatic group in Northeast Thailand prompted us to examine samples of three Austroasiatic populations in southern Laos (official designation: Lao Theung), an area inhabited by numerous ethnic groups belonging to the Mon–Khmer branch. Blood samples were collected from a total of 603 adult subjects. The HBB*E frequencies were 0.426 in the So of Khammuan Province, 0.433 in the Alak/Ngeh of Sekong Province and 0.253 in the Oy of Attapeu Province. The HBB*E frequencies in the So and Alak/Ngeh are the highest observed in Southeast Asia in representative population samples. None of the common Southeast Asian β‐thalassemia (thal) mutations were found. The results are discussed with respect to natural selection by malaria, selection time, effects of β‐thal and the ethnic history of the population of Southeast Asia. 相似文献
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Martina Galatola Erasmo Miele Caterina Strisciuglio Lorella Paparo Daniela Rega Paolo Delrio Francesca Duraturo Massimo Martinelli Giovanni Battista Rossi Annamaria Staiano Paola Izzo Marina De Rosa 《World journal of gastroenterology : WJG》2013,19(46):8659-8670
AIM:To investigated the molecular cause of very early-onset ulcerative colitis(UC)in an 18-mo-old affected child.METHODS:We analysed the interleukin-10(IL10)receptor genes at the DNA and RNA level in the proband and his relatives.Beta catenin and tumor necrosis factor-α(TNFα)receptors were analysed in the proteins extracted from peripheral blood cells of the proband,his relatives and familial adenomatous polyposis(FAP)and PTEN hamartoma tumor syndrome(PHTS)patients.Samples were also collected from the proband’s inflamed colorectal mucosa and compared to healthy and tumour mucosa collected from a FAP patient and patients affected by sporadic colorectal cancer(CRC).Finally,we examined mesalazine and azathioprine effects on primary fibroblasts stabilised from UC and FAP patients.RESULTS:Our patient was a compound heterozygote for the IL10RB E47K polymorphism,inherited from his father,and for a novel point mutation within the IL10RA promoter(the-413G->T),inherited from his mother.Beta catenin and tumour necrosis factorαreceptors-Ⅰ(TNFRI)protein were both over-expressed in peripheral blood cells of the proband’s relatives more than the proband.However,TNFRII was over-expressed only in the proband.Finally,both TNFα-receptors were shown to be under-expressed in the inflamed colon mucosa and colorectal cancer tissue compared to healthy colon mucosa.Consistent with this observation,mesalazine and azathioprine induced,in primary fibroblasts,IL10RB and TNFRII over-expression and TNFRI and TNFαunder-expression.We suggest thatβ-catenin and TNFRI protein expression in peripheral blood cells could represent molecular markers of sub-clinical disease in apparently healthy relatives of patients with early-onset UC.CONCLUSION:A synergistic effect of several variant alleles of the IL10 receptor genes,inherited in a Mende-lian manner,is involved in UC onset in this young child. 相似文献
96.
目的探讨链蛋白P120(P120ctn)、血管内皮生长因子-C(VEGF-C)在鼻咽癌组织中的表达及意义。方法采用免疫组化二步法检测56份鼻咽癌(鼻咽癌组)和15份正常鼻咽黏膜(正常组)组织中P120ctn和VEGF-C的表达情况,并分析两者间及与鼻咽癌临床病理特征的关系。结果鼻咽癌组和正常组P120ctn异常表达率分别为67.86%6、.67%,VEGF-C阳性表达率分别为83.92%、26.6%,两两比较P均〈0.05;P120ctn异常表达与鼻咽癌病理分型、TNM分期、颈部淋巴结转移相关,VEGF-C阳性表达与鼻咽癌TNM分期、颈部淋巴结转移相关;鼻咽癌组织中P120ctn与VEGF-C表达呈正相关。结论鼻咽癌的发生发展过程中常发生P120ctn和VEGF-C的表达异常,与肿瘤的浸润、转移有关,可作为判断鼻咽癌生物学特征和预后的重要指标。 相似文献
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98.
Expression of klotho and β‐catenin in esophageal squamous cell carcinoma,and their clinicopathological and prognostic significance 下载免费PDF全文
Esophageal carcinoma is one of the most common types of cancers in the world; the molecular mechanism underlying its tumorigenesis is still not well understood. This study was aimed at investigating the expression of klotho and β‐catenin in patients with esophageal squamous cell carcinoma (ESCC) and analyzing their association with clinicopathological variables and their effects on prognosis. The expression patterns of klotho and β‐catenin were determined by tissue microarray and immunohistochemical technique in ESCC and normal tissues, and their correlations with clinicopathological characteristics were investigated using univariate and multivariate analysis. The serum klotho levels in 40 ESCC patients and controls were measured by sandwich enzyme‐linked immunosorbent assay system (ELISA). The expression level of klotho was significantly lower in ESCC than in the adjacent noncancerous tissues (30 vs. 50%, P < 0.000), and the protein level was negative correlated with clinical staging, histological grade, lymph node metastasis, and invasion depth (P < 0.05). Whereas, the expression of β‐catenin was much higher in ESCC than their corresponding normal mucosa tissues (78.3 vs. 11.5%, P < 0.000), and the level of protein correlated only with histological grade and invasion depth (P < 0.05). Correlation analysis showed the expression level of klotho inversely correlated with that of β‐catenin (r = ?0.214, P < 0.01). Patients with klotho‐positive tumors had longer survival than those with klotho‐negative tumors (P < 0.01). Cox proportional hazards model analysis demonstrated that positive expression of klotho was an important factor indicating good prognosis (hazard ratio, 0.371; 95% confidence interval, 0.201–0.685; P < 0.01). ELISA showed that the level of serum klotho was markedly higher (461.50 ± 43.30 pg/mL) than control group (239.37 ± 20.65 pg/mL) (P < 0.001). Receiver operating characteristic analysis gave a cut‐off value of 327.031 of serum klotho with a sensitivity of 81.3% and specificity of 81.2% (P < 0.000). Our present study demonstrated for the first time that klotho might be a novel biomarker candidate for predicting progression and prognosis in patients with ESCC. 相似文献
99.
Regulation of cellular invasion and matrix metalloproteinase activity in HepG2 cell by connexin 26 transfection. 总被引:9,自引:0,他引:9
We previously reported that connexin (Cx) 26 expression is involved in negative growth control of HepG2 cells established from a human hepatoma. We also found that induction of E-cadherin and subsequent formation of a cell adhesion complex were induced in HepG2 cells by Cx 26 expression. To examine the exact role of Cx 26-induced E-cadherin junctions in regulating appearance of malignant phenotypes of HepG2 cells, we expressed a Cx 26 antisense oligodeoxynucleotide (AS-ODN) in an established HepG2 cell clone that has stable expression of Cx 26 genes. We investigated changes in the expression of E-cadherin, the localization of beta-catenin, and some malignant phenotypes of HepG2 clone after the suppression of Cx 26 expression by AS-ODN treatment. The AS-ODN treatment prevented the expression of Cx 26 and E-cadherin, and the localization of beta-catenin was changed from cytoplasmic membrane to the cytoplasm. In parallel, a morphological change from a monolayer of polygonal cells to multilayered colonies was induced by the treatment, indicating a change of a malignant phenotype of HepG2 cells. The activity of matrix metalloproteinase 9 (MMP-9) was elevated by the AS-ODN treatment. A concomitant increase in invasiveness of the Cx 26-expressing cells by the treatment was also observed in an in vitro assay with Matrigel matrix. These results suggest that the induction of E-cadherin and formation of the cell adhesion complex by Cx 26 expression contribute to the reversal of some malignant phenotypes of HepG2 cells. Furthermore, the Cx 26-dependent expression of E-cadherin leads to reduction of the invasiveness of the cells through suppression of MMP-9 activity. 相似文献
100.
Chong Wang Lina Qin Zhiqun Min Yiwei Zhao Lin Zhu Jing Zhu Shaojun Yu 《The European journal of neuroscience》2015,41(11):1430-1437
SOX7 mediates various developmental processes. However, its role in neuronal apoptosis remains unclear. In the present study, we investigated the expression pattern and role of SOX7 in potassium deprivation‐induced rat cerebellar granule neuron apoptosis. Our results showed that both mRNA and protein levels of SOX7 were upregulated when potassium was deprived. SOX7 overexpression promoted neuronal apoptosis, whereas knockdown of SOX7 protected neurons against apoptosis. Moreover, we found that β‐catenin activity was suppressed during apoptosis and that β‐catenin inhibition was crucial for potassium deprivation‐induced neuronal apoptosis. This suppression was mediated by an interaction between SOX7 and β‐catenin but not by protein degradation. Lastly, we showed that β‐catenin inhibition mediated the pro‐apoptotic effect of SOX7. Together, our findings demonstrated that SOX7 interfered with β‐catenin activity to promote neuronal apoptosis, which acted as a novel signaling mechanism in neuronal cell death. 相似文献