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991.
目的:探讨Wnt-1、β-catenin蛋白在子宫颈鳞状细胞癌( cervical squamous cell carcinoma, CSCC)中的表达及其与侵袭转移的关系。方法采用免疫组化EliVision法检测78例CSCC组织和30例正常子宫颈组织中Wnt-1、β-catenin蛋白表达。结果在正常子宫颈组织中,Wnt-1、β-catenin蛋白的阳性率分别为20.0%和10.0%;CSCC组织中,Wnt-1、β-catenin蛋白的阳性率分别为56.4%和74.4%,二组差异有统计学意义(P<0.001)。33例CSCC淋巴结转移中Wnt-1、β-catenin蛋白的阳性率分别为72.7%和90.9%;45例CSCC无淋巴结转移中Wnt-1、β-catenin蛋白的阳性率分别为44.4%和62.2%。 Wnt-1、β-catenin蛋白表达与CSCC的分化程度( P <0.05)、浸润深度及 FIGO 分期均有关( P <0.05),与患者年龄、肿瘤大小等均无关。Spearman相关性分析显示:Wnt-1与β-catenin蛋白表达呈正相关关系(rs =0.490,P<0.001)。结论 Wnt-1、β-catenin蛋白的表达异常可能参与CSCC的发生、发展及转移,Wnt-1、β-catenin蛋白均可作为预测CSCC侵袭、转移的潜能及临床预后的指标。  相似文献   
992.
The predictive value of the Ki-67 labelling index and its relationship with radiosensitivity in oral squamous cell carcinoma (SCC) remains controversial. We sought to evaluate whether the expression of Ki-67 antigen found in SCC of the tongue and the floor of the mouth is an indication for postoperative radiotherapy (PORT). The first study group included 34 patients who were treated only with primary surgery, while the second group included 26 patients who underwent primary surgery combined with PORT. The correlation between Ki-67 expression and loco-regional recurrence, as well as the 5-year disease-specific survival, was assessed in the two groups. Cases of high-proliferative tumours showed a significantly higher risk of loco-regional recurrence (P = 0.018) and a poorer prognosis (P = 0.001) only in the 34 patients treated with surgery alone. In multivariate Cox regression analysis, high Ki-67 expression was an independent predictor of loco-regional recurrence (HR 5.42, P = 0.029) and disease-specific survival (HR 9.02, P = 0.004). The correlation between Ki-67 expression and the risk of loco-regional recurrence in SCC of the tongue and the floor of the mouth may be useful in the selection of patients at a higher risk of recurrence who would benefit from PORT, despite adequate margins of resection and early stage of the disease.  相似文献   
993.
目的:探讨p19在血管瘤发生、发展及退化过程中的表达状况及其意义.方法:采用免疫组织化学方法(SABC法)检测人皮肤血管瘤增生期、退化期及正常皮肤组织中p19的表达水平.利用计算机图像分析技术测量不同时期血管瘤组织和正常皮肤组织p19表达的积分光密度和面积.结果:增生期血管瘤内皮细胞p19表达水平低于退化期,差异有统计学意义(P<0.05).结论:p19的表达水平与血管瘤的发生、发展与消退有关.  相似文献   
994.
The biology and pathomechanism of bilateral breast cancers is not fully understood. We compared the morphological and immunohistochemical characteristics of primary tumors in patients with synchronous bilateral breast cancers and metachronous bilateral breast cancers, with special focus on intrinsic tumor phenotype. Methods: Tumor morphology and expression of 8 immunohistochemical markers were assessed in tissue microarrays containing primary breast tumor cores from 113 metachronous bilateral breast cancers and 61 synchronous bilateral breast cancers. Analyzed markers included hormone receptors (estrogen receptor, progesterone receptor), HER2, Ki67, cytokeratin 5/6, E-cadherin, vimentin and epidermal growth factor receptor. Cutoff levels are provided in the table. Results: Metachronous bilateral breast cancers tumors had lower estrogen receptor expression (p=0.047) and higher expression of cytokeratin 5/6 (p=0.017) and of vimentin (p=0.008); in multivariate analysis only vimentin retained the significance (p=0.01). Ten (13%) and 11 (26%) of metachronous bilateral breast cancers and synchronous bilateral breast cancers had luminal A phenotype, 39 (50%) and 15 (36%) were luminal B HER2-negative, 13 (17%) and 12 (28%) - luminal B HER2-positive, 3 (4%) and 2 (5%) - HER2-positive (not luminal), and 12 (16%) and 2 (5%) had triple negative phenotype (p=0.07). Conclusion: Metachronous bilateral breast cancers, compared to synchronous bilateral breast cancers, are characterized by more aggressive phenotype, expressed by lower expression of estrogen receptor and stronger expression of cytokeratin 5/6 and vimentin; this does not, however, translate into differences in the distribution of intrinsic tumor phenotypes.  相似文献   
995.
An accurate distinction between deep muscularis propria invasion versus subserosal invasion by colonic adenocarcinoma is essential for the accurate staging of cancer and subsequent optimal patient management. However, problems may arise in pathologic staging when extensive desmoplasia blurs the junction between deep muscularis propria and subserosal fibroadipose tissue. To address this issue, forty-three (43) cases of colonic adenocarcinoma resections from 2007-2009 at The Methodist Hospital in Houston, TX were reviewed. These cases were selected to address possible challenges in differentiating deep muscularis propria invasion from superficial subserosal invasion based on H&E staining alone. Immunohistochemical staining using smooth muscle actin (SMA), smoothelin, and caldesmon were performed on 51 cases: 8 cases of pT1 tumors (used mainly as control); 12 pT2 tumors; and 31 pT3 tumors. All 51 (100%) had diffuse, strong (3+) immunoreactivity for caldesmon and smoothelin in the muscularis propria with a granular cytoplasmic staining pattern. However, the desmoplastic areas of these tumors, composed of spindled fibroblasts and myofibroblasts, showed negative immunostaining for caldesmon and smoothelin (0/35). SMA strongly stained the muscularis propria and weakly (1+) or moderately (2+) stained the spindled fibroblasts in the desmoplastic areas (the latter presumably because of myofibroblastic differentiation). Compared to SMA, caldesmon and smoothelin are more specific stains that allow better delineation of the muscularis propria from the desmoplastic stromal reaction which provides a critical aide for proper staging of colonic adenocarcinoma and subsequent patient care.  相似文献   
996.
In this article, we described a malignant myoepithelioma of the breast (MMB) in a 69-year-old woman. Breast cancer derived from myoepithelial cells is very rare, usually benign. The diagnosis of MMB based on histological and immunohistochemical finding. In this case, the author diagnosed the tumor as MMB, because tumor tissues were immunopositive for 34βE12, P63, SMA, S-100, CD10, E-Cad and Ki-67, and immunnegative for CK5/6, desmin, ER, PR and C-erbB-2, because tumor tissue showed invasive growth and local hemorrhage or necrosis, suggesting malignant, and also because there was a transition between the tumor cells and hyperplastic myoepithelium of non-tumorous ducts. The patient’s postoperative recovery is smooth and regular following of patient is essential.  相似文献   
997.
998.
We have compared mutation analysis by Amplification Refractory Mutation System (ARMS) and epidermal growth factor receptor (EGFR) mutant-specific antibodies for their ability to detect two common activating EGFR mutations in a cohort of 115 advanced non-small cell lung cancer (NSCLC), including cytology material, core biopsy, and bronchoscopic biopsies. Assessment of EGFR mutation status was performed by using antibodies and ARMS assay specific to the two major forms of mutant EGFR, exon 19 deletion E746-A750 (c.2235_2249del15 or c.2236_2250del15, p. Glu746_Ala750 del) and exon 21 L858R point mutation (c.2573T>G, p.Leu858Arg). In this study the optimal buffer for antigen retrieval was sodium citrate (pH 6.0). Q score was used to evaluate the specific mutant EGFR proteins expression. Validation using clinical material showed deletions in exon 19 were detected in 19.1% and L858R mutation in 20% of all cases by ARMS assay. A cutoff value of score 1 was used as positive by IHC. No wild type cases were immuno-reactive. The antibodies performed well in cytology, core biopsies and bronchoscopic biopsies. There were only one false positive case using L858R IHC (sensitivity 100%, specificity 98.5%, positive predictive value 96%, negative predictive value 100%). All 23 E746-A750 exon 19 deletions identified by mutation analysis were positive by IHC. The sensitivity of exon 19 IHC for E746-A750 was 100%, specificity 100%, positive predictive value 100% and negative predictive value 100%. The result of the IHC stains was finely correlated with mutations status determined by ARMS assay. Although inferior to molecular genetic analysis of the EGFR gene, IHC is highly specific and sensitive for the targeted EGFR mutations. The antibodies are likely to be of clinical value in cases especially where limited tumor material is available, or in situations where molecular genetic analysis is not readily available.  相似文献   
999.
The appearance of proliferating bile ductular structures, which is called the “atypical ductular reaction” is frequently observed in various chronic liver diseases associated. However, the origin of these increased bile ductules has been a matter of controversy. In this study, we investigated the origin of ductular cells as an aspect of relation between epithelial to mesenchymal transition (EMT) and epithelial members of liver parenchyme, such as hepatocyte and cholangiocyte by immunohistochemical staining of human liver. Thirteen specimens of surgically resected liver with biliary cirrhosis were selected. Three sets of double immunohistochemical stains were done; Hep-Par 1 - cytokeratin 19 (CK19), Hep-Par 1 - α-sm ooth mus cle actin (α-SMA) and CK19 - α-SMA. As a result, we investigated the dual expression of the markers of hepatocyte and cholangiocyte in the same cell; in ductular cell and surrounding hepatocyte. However, there seems to be no dual expression of markers for EMT with epithelial markers. This study suggests a possibility of phenotypic change of mature hepatocyte into cholangiocyte. Future studies will be necessary to determine the role that proliferating cholangiocytes play in the pathogenesis of biliary fibrosis and how cholangiocytes interact with other cell types of the liver such as hepatic stellate cells or Kupffer cells.  相似文献   
1000.
Aim: Expression of the oncofetal protein insulin like growth factor II messenger ribonucleic acid binding protein 3 (IMP3) has been shown to differentiate between benign and malignant lesions in several tissues. Our aim was to assess the immunohistochemical expression of IMP3 in inflammatory and neoplastic lesions of the gastric mucosa and to determine whether IMP3, alone or in combination with p53, could be used for identifying neoplasia of the gastric mucosa. Methods: IMP3 and p53 immunohistochemistry was performed on 57 cases of gastritis, 28 cases of dysplasia of the gastric mucosa and 63 cases of gastric carcinomas. Focal IMP3 positivity was detected in 86% of non-neoplastic lesions of the gastric mucosa. Using a simple product score (PS), 96% of non-neoplastic lesions of the gastric mucosa were assessed as IMP3(PS) negative. None of the low-grade dysplasia but 83% of high-grade dysplasia were IMP3(PS) positive. Gastric carcinomas showed IMP3(PS) positivity in 65%. Adding p53 to the diagnostic panel increased sensitivity significantly. Conclusion: High-grade dysplasia and gastric carcinomas can be distinguished from low-grade dysplasia and inflammatory lesions of the gastric mucosa with a high specificity and good sensitivity using a combination of the immunohistochemical markers IMP3 and p53.  相似文献   
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