Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A novel human endothelial cell line, AS-M, has been established from a cutaneous angiosarcoma on the scalp. The cells expressing platelet endothelial cell adhesion molecule-1 (CD31) were isolated using magnetic beads and subsequently cultured for a year. To date, the cells have undergone more than 100 population doublings (PDs). The AS-M cells manifested endothelial characteristics, such as active uptake of acetylated low-density lipoprotein labeled with 1,1'-dioctadecyl 3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil-Ac-LDL), capacity to bind the Ulex europeaus agglutin-I (UEA-I), and expression of von Willebrand factor (vWF) and CD31. The single cell-derived clone, AS-M.5, showed a constitutive expression of CD31, vWF, angiotensin-converting enzyme (ACE), endoglin (CD105), and the endothelial cell receptor tyrosine kinases KDR and Tie-1. Similarly to freshly isolated endothelial cells, the AS-M.5 responded to induction by bacterial lipopolysaccharide (LPS) by increased transcription of cell adhesion molecules and cytokines. The AS-M.5 cultures required endothelial growth supplements for optimal growth and long-term propagation in vitro. However, in contrast to normal endothelial cells, p53 gene products were detected in nuclei of AS-M.5 cells. Cytogenetic analyses consistently revealed a hypodiploid karyotype with complete loss of one homologue of several chromosomes and a homogeneous pattern of distinct karyotypic changes. Although the AS-M.5 presented characteristics suggestive of tumor cells, they did not develop into tumors when inoculated subcutaneously into nude mice. The cell line AS-M.5 could be a useful model system to study endothelial pathobiology in vitro.
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PMID:Establishment and characterization of an angiosarcoma-derived cell line, AS-M. 1474 47

We have previously reported that p53 mutations, loss of bax expression or decreased spontaneous tumor apoptosis were associated with poorer prognoses in maxillary sinus squamous cell carcinoma (SCC)(Cancer 94: 1968-1980, 2002). In the present study, we analyzed tumor angiogenesis monitored by expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and tumor microvessel density, in correlation with p53 status, spontaneous apoptosis or disease prognosis in the same group of 70 maxillary sinus SCC patients. Tumor biopsy specimens obtained prior to initiation of treatment were examined for expression of VEGF and bFGF and tumor microvessel density using immunohistological methods. Average vessel density (AVD) (range: 3-75; median: 25) and maximum vessel density (MVD) (range: 4-125; median: 53) were assessed by the number of microvessels stained with anti-CD31 mAb in tumor lesions. VEGF was expressed in 35 (50%) of 70 patients and bFGF was in 43 (61%). Patients with VEGF expression showed significantly higher levels of MVD than those without VEGF expression (57 vs. 38; P=0.019). The VEGF expression was observed more frequently in patients with p53 overexpression and/or mutation than in those with normal p53 status (P=0.048). The MVD inversely correlated with the apoptotic index (AI) defined as the number of single stranded (ss)-DNA-positive cells per 1000 tumor cells (r= -0.23; P=0.022). Patients with neck lymph node and/or distant metastases after surgery showed significantly higher levels of MVD than patients without any metastasis (64 vs. 42; P=0.048). Low histological effectiveness of radiochemotherapy correlated with bFGF expression (P=0.0059). To clarify actual prognostic factors for maxillary sinus SCC, we selected 57 patients treated uniformly with preoperative radiochemotherapy followed by maxillectomy. Kaplan-Meier analysis showed that survival was significantly worse in patients with high MVD (> or =80) than in those with low MVD (<80) (P=0.042). These data suggest that the VEGF expression in association with the p53 overexpression and/or mutations may cause increased microvascularity, decreased spontaneous apoptosis or metastases, while the bFGF expression may be associated with resistance to radiochemotherapy, thereby resulting in poorer prognoses in maxillary sinus SCC. VEGF and bFGF expression and tumor microvessel density in tumor lesions were analyzed in 70 patients with maxillary sinus squamous cell carcinoma. The VEGF expression dependent of p53 overexpression and/or mutations was associated with angiogenesis, decreased spontaneous tumor apoptosis and metastases, while the bFGF expression was associated with resistance to radiochemotherapy, resulting in poor prognosis.
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PMID:VEGF and bFGF expression and microvessel density of maxillary sinus squamous cell carcinoma in relation to p53 status, spontaneous apoptosis and prognosis. 1514 81

Previous studies from our group have demonstrated in vitro that UCN-01 (7-hydroxystaurosporine) and inhibitors of MEK1/2 interact to cause tumor cell death in a wide variety of malignant, but not in nontransformed, cell types. The present studies determined whether UCN-01 and MEK1/2 inhibitors interacted to cause tumor cell death in vivo. In vitro colony formation studies demonstrated that UCN-01 and the MEK1/2 inhibitor PD184352 interacted to synergistically kill human mammary carcinoma cells (MDA-MB-231, MCF7) with similar combination index values. Athymic mice were implanted in the rear flank with either MDA-MB-231 or MCF7 cells and tumors permitted to form to a volume of approximately 100 mm3 prior to a two day exposure of either Vehicle, PD184352 (25 mg/kg), UCN-01 (0.1-0.2 mg/kg) or the drug combination. Tumor volume was measured every other day and tumor growth determined over the following approximately 30 days. Transient exposure of MDA-MB-231 tumors or MCF7 tumors to either PD184352 or UCN-01 did not significantly alter tumor growth rate or the mean tumor volume in vivo approximately 15-30 days after drug administration. In contrast, combined treatment with PD184352 and UCN-01 significantly reduced MDA-MB-231, and largely abolished MCF7 tumor growth. Tumor control values for both cell lines were 0.36. Tumor cells isolated approximately 30 days after combined drug exposure exhibited a significantly greater reduction in plating efficiency using ex vivo colony formation assays than tumor cells that were exposed to either drug individually. Reduced tumor growth correlated with profound tumor cell death within five days of combined drug exposure, which was also evident approximately 30 days after exposure. In addition, tumor cell death correlated with a reduction in the phosphorylation of ERK1/2 and the immuno-reactivity of Ki67 and of CD31. Collectively, these findings argue that UCN-01 and MEK1/2 inhibitors have the potential to suppress mammary tumor growth in vivo which is independent of p53 status, estrogen dependency, caspase 3 levels or oncogenic K-RAS expression.
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PMID:Transient exposure of mammary tumors to PD184352 and UCN-01 causes tumor cell death in vivo and prolonged suppression of tumor regrowth. 1632 81

Ultimately aiming at a more individualized therapeutic approach in epidermoid anal cancer, this study explored the prognostic and predictive impact of a set of tumour markers. From a population-based cohort of 276 patients with epidermoid anal cancer, treated according to prospective protocols, 215 pre-treatment biopsies were investigated using immunohistochemistry. The expression of p53, p21, Cyclin A and CD31 was measured semi-quantitatively. The expression rate was classified as high when immunostaining was seen in > 5% of the tumour cells for p53 and p21, > 20% in Cyclin A and, above median vessel count for CD31. Marker expression was correlated to survival and treatment response. A high Cyclin A expression correlated significantly with improved overall (77% vs 59%, p = 0.005) and tumour-specific (81% vs 64%, p = 0.009) survival at 5 years. Also, the locoregional failure rate was significantly lower in patients with a high Cyclin A expression (12% vs 24%, p < 0.05). In a multivariate Cox analysis Cyclin A was an independent prognostic factor. A low p21 expression correlated with a reduced rate of locoregional failure (14% vs 27%, p < 0.05) but no impact on survival was found. For p53 and CD31 no significant correlations were obtained. Cyclin A may be an indicator of radiosensitivity and a valuable prognostic marker in epidermoid anal cancer.
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PMID:Prognostic significance of Cyclin A in epidermoid anal cancer. 1686 41

Due to the development of the imaging techniques and liver surgery, pathologists are encountered more frequently with preneoplastic liver lesions. Well-defined stages of human hepatocarcinogenesis have been distinguished recently. Dysplastic foci represent the earliest stage of this process. Small-cell dysplastic foci are tumor precursors, but the large-cell form of this lesion does not progress further. The next stage is the dysplastic nodule, this larger lesion can be recognized by imaging techniques and gross examination of the specimen. Low- and high-risk forms are distinguished based on the level of cytological and structural atypia. The small hepatocellular carcinomas have a diameter of less than 2 cm by definition. The small HCC of indistinctly nodular type is equivalent of in situ carcinomas in other organs and designated sometimes as early HCC. The small HCC of the distinctly nodular type can be interpreted as advanced cancer despite its small size. The distinction between these lesions can be facilitated by ancillary techniques. The so-called capillarization of the liver sinusoids during the progression is characterized by the increased expression of endothelial markers as CD31 and CD34. Immunostaining for CD44, beta-catenin and p53 has prognostic value. Molecular biological techniques reveal gradual epigenetic and DNA changes during the process of hepatocarcinogenesis. Global gene expression profiling of hepatocellular carcinomas may result in a new classification of this tumor and can reveal new potential therapeutic targets.
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PMID:[Hepatocarcinogenesis in human liver]. 1688 73

Tumor hypoxia can trigger the induction of angiogenesis. High microvessel density (MVD) as well as hypoxia-inducible factor-1alpha (HIF-1alpha) have been related to recurrent disease and tumor aggressiveness, respectively. In this study, MVD and hypoxic status were investigated in primary and recurrent endometrial carcinomas. A total of 65 primary tumors of patients with recurrent endometrial carcinoma (n = 40), and without recurrent endometrial carcinoma (n = 25) were studied. Immunohistochemical analysis was performed on paraffin-embedded tumor tissue. MVD was determined by quantitative analysis of CD31/FVIII positive vessels. Tumor hypoxia was estimated by evaluating the expression of the hypoxia-regulated gene HIF-1alphaand its target gene carbonic anhydrase IX (CA-IX). An additional 23 recurrent tumors were available for determination of MVD and HIF-1alpha expression. Effects of hypoxia on tumor protein p53 (TP53) expression were evaluated in the endometrial cancer cell lines (ECC-1), Ishikawa (derived from adenocarcinomas), and AN3CA (derived from a lymph node metastasis). MVD, CA-IX, and HIF-1alpha expression were not significantly different in primary tumors of patients with recurrence compared to the control tumors. The MVD was significantly lower, and HIF-1alpha expression was significantly higher in recurrent tumors when compared with their primary tumors (paired t test, P < 0.05). HIF-1alpha expression correlated well with TP53 expression levels in primary tumors, but not in recurrences. TP53 protein levels were highest in AN3CA cells. Hypoxic conditions induced TP53 protein in ECC-1 and Ishikawa, but not AN3CA cells. We conclude that MVD, CA-IX, and HIF-1alpha expression are not independent prognostic markers for recurrent endometrial carcinoma. The low MVD, increased HIF-1alpha protein levels, dissociation of hypoxia, and TP53 protein induction in the metastatic tumor cells (AN3CA) support a role for hypoxia in the development of recurrent endometrial carcinoma.
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PMID:Hypoxia contributes to development of recurrent endometrial carcinoma. 1735 91

The objective of this study was to explore whether a specific inhibitor of PI3K, wortmannin, could potentiate the antitumor effect of radiation in vivo, particularly on radioresistant murine tumors. C3H/HeJ mice bearing syngeneic hepatocarcinoma (HCa-I) were treated with 25 Gy radiation, wortmannin, or both. Wortmannin was administered intraperitoneally (1 mg/kg) once daily for 14 days. Tumor response to treatment was determined by a tumor growth delay assay. Possible mechanisms of action were explored by examining the level of apoptosis and regulating molecules. The expression of regulating molecules was analyzed by Western blot for p53 and p21(WAF1/CIP1), and immunohistochemical staining for p21(WAF1/CIP1), CD31 and VEGF. In the tumor growth delay assay, wortmannin increased the effect of tumor radioresponse with an enhancement factor (EF) of 2.00. The level of apoptosis achieved by the combined treatments was shown to be no more than an additive effect; peak apoptotic index was 11% in radiation alone, 13% in wortmannin alone, and 19% in the combination group. Markedly increased areas of necrosis at 24 h in the combination group were noted. Western blotting showed upregulation of p21(WAF1/CIP1) in the combination treatment group, which correlated with low levels of VEGF. Microvascular density was evidently also reduced, based on low expression of CD31. In murine hepatocarcinoma, the antitumor effect of radiation was potentiated by wortmannin. The mechanism seems to involve not only the increase of induced apoptosis but also enhanced vascular injury. Wortmannin, in combination with radiation therapy, may have potential benefits in cancer treatment.
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PMID:Enhancement of tumor radioresponse by wortmannin in C3H/HeJ hepatocarcinoma. 1743 77

The aim of this study is to analyse whether immunohistochemistry (IHC) applying a broad set of markers could be used to categorise ductal carcinoma in situ (DCIS) of the breast in distinct subgroups corresponding to the recently defined molecular categories of invasive carcinoma. Immunohistochemistry of pure DCIS cases constructed in tissue arrays was performed with 16 markers (oestrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), Bcl-2, p53, Her2, insulin-like growth factor receptor, E-cadherin, epithelial membrane antigen (EMA), CA125, keratins 5/6, 14, 19, epidermal growth factor receptor, S100, and CD31). Results in 163 cases were analysed by unsupervised hierarchical clustering. Histological classification was performed by review of whole tissue sections and identified 36 well-, 55 intermediately, and 72 poorly differentiated DCISs. Unsupervised hierarchical cluster analysis categorised DCIS into two major groups that could be further subdivided into subgroups based on the expression of six markers (ER, PR, AR, Bcl-2, p53, and Her2). In the major predominantly ER/Bcl-2-positive (luminal) group, three subgroups (AR-positive (n=33), AR-negative (n=40), and mixed (n=34)) could be identified and included 34 well-differentiated DCISs. Within the major predominantly ER/Bcl-2-negative (nonluminal) group, a Her2-positive subgroup (n=34) was characterised by 31 poorly differentiated lesions. Eight triple-negative lesions, including one positive for keratin 5/6 and two positive for p53, were encountered. Intermediately differentiated DCIS shared a comparable IHC staining pattern with well-differentiated DCIS that was distinct from poorly differentiated DCIS (P<0.001). Ductal carcinoma in situ could be categorised by IHC into two major groups and five subgroups using six markers. Morphologically, intermediately differentiated DCIS seems to have more biological similarities with well-differentiated lesions as compared to poorly differentiated lesions.
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PMID:Immunohistochemical categorisation of ductal carcinoma in situ of the breast. 1804 78

In order to illustrate the clinical and histological presentations of laryngeal atypical carcinoids and their potential course, we report six cases. We evaluated the factors predictive of local recurrence and metastatic diffusion. For each case, we noted the mitotic index, the quality of the resection, the limits of the tumor and the presence of necrosis. An immunohistochemical study was carried out with a series of antibodies (cytokeratins; D(2)40; CD31; MIB1; P53; P16; TTF1...). The clinical presentation we observed was quite similar to that reported in the literature. These tumors are CK7+, CK8+, CK19+, CK5-6-, CK14- and CK20-. P16 is constantly positive. Only the mitotic index and the lymphatic presence of embolus were correlated with the time course. The tumor is more aggressive when the mitotic index is high and an unfavorable course is observed when there are lymphatic emboli or when the Ki67 index is higher than 5%.
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PMID:[Atypical carcinoid of the arytenoid: report of six cases]. 1853 8

Chordoid gliomas are rare, slow-growing neoplasms of the anterior third ventricle. We reported a case of chordoid glioma in a 41-year-old man with obstructive hydrocephalus. Histologically, the tumor consisted of polygonal epithelioid cells admixed with elongated cells in a myxoid stroma. A prominent lymphoplasmacytic infiltrate was present. The tumor cells expressed glial fibrillary acidic protein (GFAP), epithelial membrane antigen (EMA), vimentin, CD31, CD34, epidermal growth factor receptor (EGFR) and S100 but were negative for pankeratin and E-cadherin. The percentage of Ki67 positive cells was approximately 3%. Weak p53 immunoreactivity was seen in less than 10% of the cells. Array comparative genomic hybridization performed on this case, as well as on four other archived cases, showed losses at several loci. Fluorescence in situ hybridization (FISH) confirmed consistent genetic alterations at 9p21 and 11q13. These are the fifth through ninth reported cases of chordoid gliomas with molecular characterization suggesting a distinct genetic origin from other gliomas.
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PMID:Chordoid glioma: a case report and molecular characterization of five cases. 1865 91


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