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101.
Expression of p53 protein in infiltrating and in-situ breast carcinomas.   总被引:6,自引:0,他引:6  
Five antibodies directed against the whole or part of p53 protein have been used to detect the protein immunohistochemically in 70 infiltrating breast carcinomas and 10 ductal carcinomas in situ. Mutations are known to occur in different conserved domains, and the antibodies employed spanned the expected sites. p53 protein was identified in 53 per cent of infiltrating carcinomas using the antibodies PAb 240, PAb 1801, C19, and JG8. The antibody PAb 421 detected the protein in 31.5 per cent; all positive with the other antibodies. Well-differentiated oestrogen receptor-positive tumours had a low incidence of p53 detection. Variation in the percentage of reactivity was seen between carcinomas and in some cases between different antibodies in the same cancer. Those carcinomas with a high percentage of positive cells with all antibodies were more likely to have metastasized to nodes, be at an advanced stage, and be oestrogen receptor-negative/epidermal growth factor receptor-positive. There was no significant correlation with c-erbB-2 protein expression or retinoblastoma protein loss. p53 protein was detected in a high proportion of cells in three of the six comedo ductal carcinomas in situ studied but either not at all or at a lower level in tumours of the cribriform type. p53 mutations are common in breast carcinomas, but heterogeneity within individual tumours is frequent. Marked expression of p53 appears to relate to tumour progression.  相似文献   
102.
103.
本文应用抗癌基因ras表达产物P21ras蛋白的大鼠单克隆抗体建立的双抗体夹心ELISA法,检测了肝癌及癌病变前病人血清中p21ras蛋白的浓度。所获阳性检出率分别为:慢性乙型肝炎为13.0%(12/92),肝硬化为27.8%(10/36)和肝癌为50.0%(8/16)。另外,对试验方法的敏感性、特异性及稳定性,以及检测P21ras蛋白与AFP的关系进行了评价。结果表明,P21ras蛋白的过高表达发生在肝细胞癌变之前。提示在慢性乙型肝炎及肝硬化病人血清中检出P21ras蛋白,是预测肝细胞癌变的危险信号。  相似文献   
104.
Nonfunctioning islet cell tumors or pancreatic endocrine tumors are the most common type of malignant islet cell tumor. Although previously detected usually at an advanced stage because of mass effect, the early detection rate of small localized disease has been increasing. To date it has been difficult to predict the clinical behavior in localized regional nonfunctioning tumors. To investigate potential markers predicting malignancy and poor prognosis in nonfunctioning pancreatic endocrine tumors, we analyzed the expression of Ki-67, topoisomerase IIα (Topollα), and p27, as well as a variety of clinicopathologic parameters in 76 cases of nonfunctioning islet cell tumors (23 benign cases and 53 malignant cases). Ki-67, Topollα, and p27 labeling indices were significantly different between benign and malignant tumors. Expression of Ki-67, Topollα, and p27 were associated with survival in patients with a malignant tumor in a univariate setting. However, only p27 and Topollα were jointly associated with survival in multivariate analysis. Immunohistochemical staining for p27, Topollα, and Ki-67 can be helpful in the diagnosis of nonfunctioning pancreatic endocrine tumor. Analysis of p27 and Topollα may also have potential utility as prognostic factors for malignant tumors.  相似文献   
105.
目的研究人染色体11p15.5Beckwith-Wiedemann综合征致病位点新基因C11orf21的生物学功能。方法用RT-PCR和Northern印记方法分析C11orf21基因的表达;研究C11orf21蛋白功能用Western印记和细胞培养方法。结果检测到C11orf21基因在成人和胎儿心脏和肝脏等组织转录,在心脏有较强的表达并有0.9和3.1kb两个转录物。C11orf21蛋白在COS-1和Hela细胞细胞质表达,蛋白相对分子质量为14kDa。结论初步分析显示C11orf21是11p15.5Beckwith-Wiedemann综合征致病位点的一个非印记基因,在成人心脏有较强表达的局限细胞质蛋白。  相似文献   
106.
Chang MS  Kim WH  Kim CW  Kim YI 《Histopathology》2000,37(4):309-315
AIMS: To clarify the relationship between the Epstein-Barr virus (EBV) and gastric carcinoma with lymphoid stroma (GCLS) in Koreans, and to characterize the EBV-positive GCLS. METHODS AND RESULTS: EBV infection was examined using EBER in-situ hybridization and polymerase chain reaction in 45 cases of GCLS among Koreans, and in 292 consecutive cases of gastric carcinomas without lymphoid stroma (non-GCLS) as controls. EBV infection was found in 30 tumours (67%) of GCLS and 10 tumours (3.4%) of non-GCLS (P < 0.05). EBV-positive GCLS was more prevalent in males, poorly differentiated histological type and diffuse type in Lauren's classification, and tended to be located more in the middle third of the stomach than EBV-negative GCLS (P < 0.05). p53 overexpression was observed in 22% of GCLS (17% of EBV-positive GCLS and 33% of EBV-negative GCLS), and 34% of non-GCLS (EBV-positive GCLS vs. non-GCLS: P = 0.056). The survival of the patient with GCLS was not correlated with EBV infection or p53 immunoexpression (follow-up period: 11-97 months). CONCLUSIONS: GCLS in Koreans is strongly associated with EBV infection. The prognosis in GCLS is not dependent upon either the status of EBV infection or the status of p53 immunoexpression.  相似文献   
107.
Summary The effects of beta-adrenergic agonists such as isoproterenol, norepinephrine and epinephrine upon the adenylate cyclase activity of human fat cell ghosts were tested, each alone and in combination with the beta-blocking agent propranolol. Saturating concentrations of these agents showed a 2–6.5-fold increase of enzyme activity without addition of any artificial cofactors. Isoproterenol was more potent in stimulating the enzyme system than epinephrine and nor-epinephrine. Propranolol caused a dose-dependent rightward shift of the log-dose response curve of these beta-adrenergic agonists. The assay of human fat cell adenylate cyclase in vitro may provide a simple and convenient assay system for the screening of beta-adrenergic drugs of potential therapeutic importance.Herrn Prof. Dr. Dr. h.c. G. Schettler zum 60. Geburtstag gewidmet  相似文献   
108.
膀胱尿路上皮癌MMP-2表达及其与FAK、p53、bcl-2、Ki-67的关系   总被引:16,自引:1,他引:16  
目的 比较不同分化和浸润程度膀胱尿路上皮癌MMP—2表达及其与FAK、p53、bcl—2和Ki—67的关系。方法 采用免疫组化EnVision法对83例膀胱尿路上皮癌和68例非肿瘤尿路上皮,进行MMP—2、FAK、p53、bcl—2和Ki—67的表达检测。结果 MMP—2在肿瘤组织中的表达显著高于非肿瘤性移行上皮,其表达强度随肿瘤分化程度降低和浸润深度增加而显著增强。分化差和浸润性膀胱癌中FAK和p53表达增强,并与MMP—2表达呈正相关;分化差膀胱癌中Ki—67表达增强而bcl—2表达丢失,Ki—67与MMP—2表达呈正相关。结论 在膀胱尿路上皮癌的进展和分化过程中,肿瘤分化程度越低,肿瘤细胞分泌MMP—2越多,其浸润和转移的能力也越强。FAK、p53、Ki—67和bcl—2不但与肿瘤细胞的生长密切相关,还可能直接或间接地参与了MMP—2的调控。  相似文献   
109.
The progressive reduction in p27(Kip1) (p27) protein immunohistochemical staining with increasing histological grading is a well-established finding occurring in breast cancer, and its role as diagnostic complement and prognostic marker has been thoroughly evaluated. To clarify whether this test may be applied to breast cytopathology, we performed p27 immunostaining on fresh fine-needle cytology (FNC) samples from 10 benign and 40 malignant breast lesions. On average, p27 immunostaining was significantly lower in carcinomas than in benign lesions (P < 0.005). In particular, among carcinomas, p27 immunostaining progressively reduced from well-to poorly differentiated lesions (G1 vs. G2, P < 0.05; G1 vs. G3, P < 0.001; G2 vs. G3; P < 0.001). A similar trend was noted in a subgroup of 20 matched FNCs and histological samples of breast carcinomas, when p27 immunostaining on FNCs was stratified according to the histological grading (G1 vs. G2, P = 0.18; G1 vs. G3, P < 0.05; G2 vs. G3, P < 0.05). In addition, p27 immunostaining on FNCs showed a good positive correlation with that on histology (Spearman R = 0.58; P < 0.01), with a diagnostic concordance between samples of 85%, by using the standard 50% positive cell cutoff. Taken in concert, our data suggest that p27 immunostaining is a reliable marker of tumor cell differentiation in breast cytopathology as well as in histopathology. Accordingly, staining FNCs for p27 may be an useful complement in addition to cytological grading in the preoperative assessment of breast cancer.  相似文献   
110.
To clarify the mechanisms underlying cell cycle promotion in malignant germ cell tumours of the ovary (MGCTOs), beta-catenin and components of the pRB pathway, cyclin D1 and p16, were analysed in relation to cell proliferation. Immunohistochemically, p16 protein was not expressed in a number of MGCTOs (9 of 42 tumours: 21.4%) and was associated with p16 gene (INK4A) promoter 5'-CpG islands methylation. Amplification of the cyclin D1 gene (CCND1) was detected in a small number of MGCTOs (5 of 42 tumours: 13.5%). Reduced expression of p16 due to promoter methylation correlated significantly with increased cell proliferation as evidenced by Ki-67 labelling index (p < 0.001) and mitotic index (p < 0.01). In some tumour types, nuclear localization of beta-catenin has been reported to be associated with beta-catenin gene (CTNNB1) mutation, cyclin D1 overexpression, and increased cell proliferation. Nuclear localization of beta-catenin, which was observed in MGCTOs other than dysgerminoma, was not associated with cyclin D1 expression and increased cell proliferation, but appeared to be related to tumour differentiation. Furthermore, CTNNB1 mutations were not detected in any of the MGCTOs examined. Our results suggest that reduced expression of p16 due to INK4A promoter methylation is one of the principal factors that promote cell proliferation in MGCTOs. Thus, p16 may be a novel target for gene therapies to treat MGCTOs.  相似文献   
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