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)

An association has been reported between nuclear p53 protein expression in tumour cells and a poor outcome in patients with colorectal cancer (CRC). In this study we investigated the prognostic significance of nuclear p53 protein expression in CRC liver metastases after curative hepatic resection. The study population consisted of 69 consecutive patients who underwent curative hepatic resection for metastases from CRC at our Institution between February 1987 and October 1993. Immunohistochemical expression of p53 protein was evaluated in formalin-fixed paraffin-embedded sections of CRC liver metastases using the monoclonal antibodies (MAbs) D01 and Pab 1801. The Cox proportional hazards model was used in forward stepwise regression to assess the relative influence of different prognostic factors. Forty-four (63.8%) CRC liver metastases were p53-positive. Kaplan-Meier survival curves demonstrated that patients with p53-positive metastases had a median survival of 27 months versus 93 months for patients with p53-negative metastases (P < 0.01). The 3 and 5 years survival rates were 31.5 and 21.0% in patients with p53-positive metastases and 71.8 and 53.1% in patients with p53-negative metastases. At multivariate analysis p53 protein status was the single best predictor of survival (P = 0.0079); the odds ratio of death among patients with p53-positive tumours was 2.53. Nuclear p53 protein expression in hepatic metastases from CRC is an independent prognostic factor of survival following liver resection. These findings may be of clinical importance in the selection of patients more likely to benefit from liver resection and could be used as criteria for stratification in trials on adjuvant therapy.
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PMID:Nuclear p53 protein expression in resected hepatic metastases from colorectal cancer: an independent prognostic factor of survival. 979 97

Paired colorectal liver metastases (CLM) and normal tissue samples from a consecutive series of 36 patients were studied prospectively. MIB-1 expression was studied by immunohistochemistry on paraffin-embedded sections. DNA ploidy and S-phase fraction (SPF) measurements were performed by flow cytometry on frozen tissues. Mutations within the p53 (exons 5-8) and c-Ki-ras (codons 12 and 13) genes were detected by PCR single-strand conformation polymorphism analysis followed by sequencing. A high correlation was observed between the MIB-1 LI and SPF value (rho=0.81; P<0.01). Moreover, p53 gene mutations were associated with either high MIB-1 LI and high SPF. In univariate analysis, SPF and MIB-1 levels were related to risk of death. The association between overall survival and DNA-ploidy or p53 mutations did not reach statistical significance, but a slightly better survival was observed for patients either with DNA-diploid tumours or without mutations (P=0.05 and P=0.06, respectively). SPF was shown by multivariate Cox model analysis to be an independent prognostic variable and thus it might be a useful prognostic factor in patients with CLM.
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PMID:Prognostic significance of proliferative activity, DNA-ploidy, p53 and Ki-ras point mutations in colorectal liver metastases. 985 27

Small cell carcinoma of the stomach has an aggressive feature, and the survival rate of the patients is poor. The purpose of this study was to determine the clinical course, and effects of histopathologic characteristics of specific tumors including DNA contents and immunohistochemical aspects in patients with small cell carcinoma of the stomach. Medical records of 8 patients who presented with small cell carcinoma of the stomach were retrospectively reviewed. Primary tumors were studied by flow cytometric analysis and immunohistochemical staining for the p53 protein, PCNA (proliferating cell nuclear antigen), factor VIII related antigen (specific for endothelial cells), VEGF (vascular endothelial growth factor) and PD-ECGF (platelet-derived endothelial cell growth factor). DNA aneuploid was observed in 4 cases. Staining for the p53 product was positive in 50% of all the cases. The average PCNA labeling rate (LR) was 71.3+/-9.9%. Positive VEGF expression was found in 7 tumors and positive PD-ECGF expression was found in all tumors. The estimated median survival was 252 days for all the patients. Liver metastases were observed in 4 of the 8 patients, however, surgery and chemotherapy have given us one long-term survivor (43 months). Higher PCNA LR of small cell carcinoma may be an unfavorable characteristic of biological behavior. Moreover, both VEGF and PD-ECGF positivity are well-characterized inducers of hepatic metastasis.
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PMID:Highly aggressive behavior and poor prognosis of small cell carcinoma in the stomach: flow cytometric and immunohistochemical analysis. 1037 53

An ultra-high metastatic model of human colon cancer was developed in order to represent highly malignant patient disease for which there is no current model. Surgical orthotopic implantation (SOI) of a histologically intact liver metastasis fragment derived from a surgical specimen of a patient with metastatic colon cancer was initially implanted in the colon, liver and subcutaneously in nude mice. This tumor did not metastasize for the first 10 passages. At the eleventh passage, the tumor exhibited metastasis from the colon to the liver, spleen, and lymph nodes. At this time, two selective passages were carried out by transplanting resulting liver metastases in the nude mice to the colon of additional nude mice. After these two passages, the tumor became stably ultra-metastatic and was termed AC3488UM. One-hundred percent of mice transplanted with AC3488UM with SOI to the colon exhibited local growth, regional invasion, and spontaneous metastasis to the liver, lymph nodes, and spleen. While the maximum size of the primary tumor was 0.9 g, the metastatic liver was over 9 times the weight of the normal liver with the maximum weight of the metastatic liver over 12 g. Liver metastases were detected by the tenth day after transplantation in all animals. Half the animals died of metastatic tumor 25 days after transplantation. Histological characteristics of AC3488UM tumor were poorly differentiated adenocarcinoma of colon. Mutant p53 is expressed heterogeneously in the primary tumor and more homogeneously in the liver metastasis suggesting a possible role of p53 in the liver metastasis. The human origin of AC3488UM was confirmed by positive fluorescence staining for in situ hybridization of human DNA. The AC3488 human colon-tumor model with its ultra-high metastatic capability in each transplanted animal, short latency and a short median survival period is different from any known human colon cancer model and will be an important tool for the study of and development of new therapy for highly metastatic human colon cancer.
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PMID:An ultra-metastatic model of human colon cancer in nude mice. 1039 Jan 46

Seven (3.3%) of 213 patients who underwent surgery for early colorectal cancer (invasion limited to no deeper than the submucosa) at the National Cancer Center Hospital, Tokyo, between 1986 and 1995 had synchronous (2 patients) or metachronous (5 patients) liver metastases. The average period from surgical resection of the primary colorectal cancer to the diagnosis of liver metastases was 25 months (range, 0-52 months). The clinicopathologic and immunohistochemical features of the primary lesions in these patients were compared with these features in the lesions in consecutive patients with early colorectal cancer who had no evidence of liver metastases within at least 5 years after colorectal resection. Venous invasion was more frequent in the primary lesions with liver metastases than in those without liver metastases (57% vs 0%; P = 0.0035). Expression of p53 and CD44v9 was more frequent in the primary lesions with liver metastases (71% and 100%) than in those without metastases (56% and 72%). In contrast, MUC2 expression was more frequent in the primary lesions without liver metastases (72%) than in those with metastases (43%). Venous invasion is considered to be closely related to liver metastasis, and the immunohistochemical expression of p53 and CD44v9 provides useful information for identifying those patients with early colorectal cancer who have a high risk of developing liver metastases.
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PMID:Clinicopathologic and immunohistochemical study of early colorectal cancer with liver metastases. 1043 8

Herpes simplex virus type 1 (HSV 1) vectors are under investigation for use in gene therapy for colorectal cancer liver metastases. Approximately 60% of colorectal cancers possess p53 mutations, and p53 mutations can cause tumor cell resistance to radiation therapy and chemotherapy. p53 is also known to co-localize with at least one HSV 1 protein and influence HSV 1 gene expression. The purpose of this study was to determine if the loss or mutation of p53 in tumor cells alters the cytotoxicity of HSV 1 vectors. HSV 1 vector-mediated in vitro cytotoxicity assays were performed using stable transfectants of SAOS-2-LM2 cells and WiDr cells that express no p53, wild-type p53, mutant p53, or both wild-type p53 mutant p53. All stable transfectants were equally susceptible to HSV 1 vector cytotoxicity, and cell lines with mutant p53 were not resistant to HSV 1 vectors. These results provide additional rationale for the application of HSV 1 vector gene therapy for colorectal cancer.
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PMID:Influence of p53 on herpes simplex virus type 1 vectors for cancer gene therapy. 1045 21

Colorectal cancer (CRC) is the second commonest cause of cancer death in the UK, with greater than 40% of these patients destined to die of the disease despite current medical management. Death is commonly due to liver metastases with sequelae including progressive liver dysfunction. Most patients with liver metastases present with tumours that are unresectable and incurable with existing therapies. The median survival for CRC patients after diagnosis with liver metastases is approximately 6 months or less. The human p53 gene is a tumour suppressor gene involved in the control of cell proliferation. Loss of wild-type p53 function is associated with the uncontrolled growth of many types of human cancers. The reintroduction and expression of wild-type p53 into p53 altered tumour cells has been shown to suppress tumour growth or induce apoptosis in both in vitro and in vivo models. In our experience greater than 50% of CRC tumours have p53 alterations. This study seeks to evaluate the safety, biological efficacy and the effectiveness of wtp53-CMV-Ad treatment which is a recombinant adenoviral vector containing the wild-type human p53 gene. It will be administered by infusion via the hepatic artery, for the regional gene therapy of malignant liver tumours. Study patients will have incurable metastatic (CRC) malignant tumours of the liver with evidence of p53 alteration in their liver tumours. In vitro studies have demonstrated p53-specific antiproliferative effects of wtp53-CMV-Ad on human liver tumour cells and in vivo studies have demonstrated p53-specific antiproliferative effects on human liver tumour cells. The vector Ad-p53 is a recombinant, replication-defective adenovirus based on adenovirus serotype 5. It contains a sequence encoding wild-type p53 whose expression is under the control of the human cytomegalovirus immediate early promoter-enhancer. This construct will be growth in 293 cells which contain the adenoviral E1A and E1B coding sequences which have been removed from the vector to render it replication defective. The study design is an open-label, non-randomised, single-dose, dose escalation Phase I/II clinical trial anticipated to involve a maximum of 19 patients. wtp53-CMV-Ad will be administered by infusion in a reservoir connected to the hepatic artery, for regional gene therapy (surgically implanted pump) in 3 escalating doses to successive cohorts of 3 patients each until the maximum tolerated dose is determined. Subsequently, 10 patients will be treated with this dose. Regional wtp53-CMV-Ad therapy will be administered as a single bolus infusion via hepatic artery catheter. The route of administration of wtp53-CMV-Ad via hepatic artery infusion is designed to maximise gene therapy exposure to the malignant tumours while minimising exposure to normal tissues outside the liver. The clinical protocol is designed to monitor treatment toxicity. Another objective is to evaluate the biological efficacy, including efficiency and stability of gene transfer by analysis of tumour tissues following therapy. As an important part of this objective the pharmacokinetics of wtp53-CMV-Ad will be studied. Clinical evidence of anti-tumour efficacy will also be collected. In addition, the safety and efficacy of different doses levels of wtp53-CMV-Ad will be studied.
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PMID:A phase I/II study of hepatic artery infusion with wtp53-CMV-Ad in metastatic malignant liver tumours. 1046 36

Disseminated disease, especially to the liver, constitutes the major risk of recurrence for colorectal cancer patients. However, successful resection can still be achieved in 25-35% of colorectal cancer patients with isolated metastases. To evaluate the clinical value of occult micrometastatic disease detection in lymph nodes, we tested genetic (K-ras and p53 gene mutations) and epigenetic (p16 promoter hypermethylation) molecular markers in the perihepatic lymph nodes from colorectal cancer patients with isolated liver metastases. DNA was extracted from 21 paraffin-embedded liver metastases and 80 lymph nodes from 21 colorectal cancer patients. K-ras and p53 gene mutations were identified in DNA from liver metastases by PCR amplification followed by cycle sequencing. A sensitive oligonucleotide-mediated mismatch ligation assay was used to search for the presence of K-ras and p53 mutations to detect occult disease in 68 lymph nodes from tumors positive for these gene mutations. Promoter hypermethylation at the p16 tumor suppressor gene was examined in both liver lesions and lymph nodes by methylation-specific PCR. Sixteen of the 21 (76%) liver metastases harbored either gene point mutations or p16 promoter hypermethylation. Twelve of the 68 lymph nodes were positive for tumor cells by molecular evaluation and negative for tumor cells by histopathology and cytokeratin immunohistochemistry, whereas none were positive for tumor cells by histopathology or negative for tumor cells by molecular analysis (P = 0.0005, McNemar's test). Moreover, in three patients with lymph nodes that were histologically negative at all sites, molecular screening detected tumor DNA at one or more lymph nodes. Survival analysis showed a median survival of 1056 days for patients without evidence of lymph node involvement by molecular analysis and 165 days for patients with positive lymph nodes by this approach (P = 0.0005). These results indicate that lymph node metastasis screening in colorectal cancer patients by molecular-based techniques increases the sensitivity of tumor cell detection and can be a good predictor of recurrence in colorectal cancer patients with resectable liver metastases.
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PMID:Molecular detection of neoplastic cells in lymph nodes of metastatic colorectal cancer patients predicts recurrence. 1049 18

A malignant rhabdoid tumor of the colon is very rare and only three cases have been previously described. A 76-year-old man was admitted to the hospital complaining of epigastralgia. An elastic mass was palpable in the right upper abdomen. A barium enema and endoscopic examination showed a giant gyrate tumor arising from the cecum. Abdominal ultrasonography and a computed tomography scan revealed the tumor to be located in the colon associated with multiple liver metastases and gallbladder stones. A right colectomy and cholecystectomy were thus performed. The tumor was histologically composed of sheets of large round and polygonal nuclei with vesicular chromatin, and abundant acidophilic cytoplasm, often containing hyalin-like inclusion. The cytoplasm was positive for vimentin and neuron-specific enolase, and hyaline globules of the rhabdoid tumor cells stained positive for cytokeratin in some cells. Transmission electron microscopy showed characteristic rhabdoid cells with an aggregation of intermediate filaments. A histologic diagnosis of malignant rhabdoid tumor of the colon was made. The tumor demonstrated several unusual findings for malignant rhabdoid tumors including diploidy by a flow cytometric analysis, and positive nuclear immunohistochemical staining for p53 protein and Ki-67 antigen. We report herein the third known case of a pure colonic rhabdoid tumor.
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PMID:Malignant rhabdoid tumor of the colon: report of a case. 1055 35

The presence and type of mutations of the p53 tumor suppressor gene were determined in 40 patients undergoing curative hepatic resection for metastatic colorectal carcinoma. This represents the largest series in the literature on the screening of p53 mutations for liver metastases. The analysis was performed in exons 5-9 by denaturing gradient gel electrophoresis followed by direct sequencing. Forty-five percent of tumors showed mutation in p53, and this was observed only in exons 5-8. Mutations at codon positions 167, 196, 204, 213, 245, 281, 282, 286, and 306; deletion of codon 251 and of the first nucleotide of codon 252; and Leu residue (CTC) insertion downstream codon 252 are reported for the first time in colorectal liver metastasis. Mutations at codon positions 163, 248, and 273 have been reported previously. Correlation of p53 status with clinical parameters showed that patients with mutated p53 had a statistically higher number of lesions when compared with patients with wild-type p53 (P<0.050). In particular, of patients with mutated p53, 41% had three or more metastases compared with 14% of patients with wild-type p53. Synchronous metastases were present in 70% of the patients with p53 mutations and in only 29% of patients with wild-type p53 (P<0.025). In addition, patients with p53 mutations are more likely to develop recurrence (73%) compared with patients with wild-type p53 (33%; P<0.001). Other factors considered, including preoperative carcinoembryonic antigen level, bilobar distribution, and size of the lesion(s), did not show significant correlation with p53 status. These results suggest that p53 status might be an important prognostic indicator to predict the pattern and likelihood of treatment failure after hepatic resection.
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PMID:Characterization of p53 mutations in colorectal liver metastases and correlation with clinical parameters. 1058 41


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