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)

Human malignant gliomas (glioblastomas and anaplastic astrocytomas) are the most frequent brain tumors and are associated with a variety of genetic alterations including retinoblastoma (RB) and p53 gene mutations, loss of interferon alpha and beta (IFNA, IFNB) genes and lack of O6-methylguanine-DNA methyltransferase (MGMT) expression. Yet, in the studies performed to date, the relationship between these alterations has not been addressed. In this report, we have studied gene expression in 29 malignant glioma cell lines and have determined that, although loss of the interferon genes and loss of RB, p53 and MGMT mRNAs are frequent events, combinations of genetic alterations involving these four proven or putative tumor-suppressor genes are relatively infrequent. The exception was loss of RB mRNA, which may be associated with lack of MGMT mRNA.
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PMID:Lack of expression of tumor-suppressor genes in human malignant glioma cell lines. 150 94

In order to elucidate the significance of the adenoma-carcinoma sequence in gastric carcinogenesis from a genetic point of view, we examined microsatellite alterations (replication error and loss of heterozygosity) on chromosomes 2p (D2S123), 3p (D3S1317), 5q (D5S409), 9p (IFNA), and 13q (D13S153) as well as p53 gene mutations in 13 adenomas and 23 differentiated adenocarcinomas including 8 early carcinomas of the stomach. Replication error was detected in only one of the adenomas (8%, 1/13) at the D5S409 locus and in none at the other loci, and loss of heterozygosity was also an infrequent event found in one adenoma (14%, 1/7 informative cases) at D5S409 and in none at the other loci. A p53 gene mutation was detected in one (8%, 1/13) of the adenomas. Thus, microsatellite alterations and p53 gene mutations are rare events in adenomas. In differentiated adenocarcinomas, replication error was detected in 4 (17%, 4/23) at single or multiple loci, and loss of heterozygosity was observed frequently at D3S1317 (25%, 3/12), D5S409 (67%, 6/9), and IFNA (26%, 5/19). Mutations in the p53 gene were detected in 9 (39%, 9/23) of the differentiated adenocarcinomas. Microsatellite alterations on several chromosomes and mutations in the p53 gene were frequent in differentiated adenocarcinomas, even those at an early stage. These results suggest that the adenoma-carcinoma sequence is relatively rare in gastric carcinogenesis, and that the majority of differentiated adenocarcinomas of the stomach may develop through a de novo pathway.
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PMID:Microsatellite alterations in adenoma and differentiated adenocarcinoma of the stomach. 772 62

Nasopharyngeal carcinoma, which is very frequent in southern China, has in previous investigations been found to be associated with a number of risk factors, including a disease susceptibility gene linked to the HLA-region, p53 alleles and deletions of the chromosome 9p21-22 region, which includes the IFNA and p16 loci. We have therefore studied 64 patients (54 males and 10 females) with nasopharyngeal carcinoma and 99 healthy controls from the Guizhou province in southern China with respect to association with the SspI polymorphism at the IFNA17 locus, and the possible interaction between IFNA17 and p53 alleles in the etiology of nasopharyngeal carcinoma. The frequency of the SspI A1 allele was much higher (P < 10(-10)) in Chinese patients and controls than in a previously reported study of Swedes. Among the patients there was a significant increase in the frequencies of the SspI A2 allele (P = 0.011) and SspI 2-2 genotype with an OR (odds ratio) of 2.76, 95% CI = 1.13-6.73 in relation to the SspI 1-1 type. When combinations of SspI and the p53 codon 72 (BstUI) genotypes were studied a highly significant risk figure was found for the SspI 2-2/BstUI 1-1 (pro/pro) combination (OR = 8.2, 95% CI = 2.2-30.0). No other combinations showed significant risk figures. There was no significant interaction between the SspI 2-2 and BstUI 1-1 types indicating that IFN-alpha and p53 genotypes behave as independent risk factors. Since IFN-alpha is located close to the tumor suppressor gene p16, and intronic p53-haplotypes show stronger association with nasopharynx cancer than the codon 72-polymorphism, both associations may be due to linkage disequilibrium with adjacent genes influencing cell-cycle control.
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PMID:Interferon-alpha and p53 alleles involved in nasopharyngeal carcinoma. 911 Nov 94

Defective mismatch repair has been detected in human colorectal and endometrial carcinomas which exhibit microsatellite instability (MIN). The purpose of this study was to search for MIN in melanoma. Paraffin-embedded neoplastic and non-neoplastic control cells were obtained from 20 untreated individuals with cutaneous malignant melanoma. Breslow thickness ranged from 0.2-7.4 mm (mean 1.4). Cells were carefully scraped from glass slides so that tumor and control DNA could be isolated and then amplified by polymerase chain reaction (PCR) at seven separate microsatellites localized to specific chromosome regions: 1p22 (D1S187), 5q11.2-13.3 (D5S107), 6q21-23.3 (D6S357), 9p21 (IFNA), 11p15.2 (D11S861), 17p13.1 (D17S786), and 18q11 (D18S34). Heterozygosity indices were > or = 0.70. Loci from these chromosome regions were chosen because of cytogenetic abnormalities reported in melanoma (1p, 6q, 9p), location of common oncogenes (11p-HRAS, 17p-TP53), or use in other MIN studies (5q, 18q). Five individuals (25%) demonstrated MIN. There was no correlation with tissue thickness. One individual demonstrated MIN at two loci and one individual demonstrated loss of heterozygosity. The results indicate that MIN occurs in melanoma, albeit less frequently than reported in carcinomas.
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PMID:Microsatellite instability in malignant melanoma. 966 3

Bronchiolo-alveolar carcinoma (BAC) is a type of lung adenocarcinoma characterized by growth along the alveolar wall. It is divided into two subtypes: sclerosing BAC (SBAC), which has central fibrosis, and non-sclerosing BAC (NSBAC), which lacks central fibrosis. We compared the genetic alterations in these two types of BAC with those in atypical adenomatous hyperplasia (AAH). There were 39 cases of SBAC, 19 of NSBAC and 20 of AAH. To detect the loss of heterozygosity (LOH) we used the microsatellite markers D3S1234 and D3S1300 on chromosome 3p, IFNA and D9S144 on 9p, and TP53 on 17p. We also used polymerase chain reaction-SSCP analysis and direct sequencing to examine a point mutation of the p53 gene at exons 5-8. At the TP53 locus, the frequencies of LOH showed a statistical rank-difference correlation among AAH, NSBAC and SBAC. On chromosomes 3p and 9p there were no statistical differences of LOH among AAH, NSBAC and SBAC. We detected a significant statistical rank-difference correlation in the p53 mutation among AAH, NSBAC and SBAC. These findings suggest that a process of multistep carcinogenesis from AAH through NSBAC to SBAC might occur in some cases of adenocarcinoma, and LOH of 3p and 9p might be an early event of carcinogenesis, while the p53 mutation might be a later event.
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PMID:Correlation between genetic alterations and histopathological subtypes in bronchiolo-alveolar carcinoma and atypical adenomatous hyperplasia of the lung. 1110 49

The genetic alterations responsible for the development of cutaneous lymphoma are largely unknown. Chromosome region 9p21 contains a gene locus encoding an inhibitor of cyclin-dependent kinase 4, and heterozygous deletions of this tumor suppressor gene (p16) have been shown in a variety of malignant tumors. We studied 11 randomly selected cutaneous CD30-positive large cell lymphomas. Several areas containing 20-50 CD30-positive lymphocytes were microdissected in each case and subjected to single-step DNA extraction. Loss of heterozygosity analysis was performed using polymorphic markers at 9p21 (IFNA, D9S171, D9S169) and 17p13 (TP53). Samples from normal cells apart from CD30-positive lymphocytes, e.g., CD30-negative lymphohistiocytic infiltrates and normal epidermal layer, were also obtained in all cases from the same slide for comparison with the tumor samples. Expression of CD30 and T-lineage antigens (CD3, CD45Ro) was confirmed in all cases. Immunohistochemical staining for p16 and p53 was performed using the monoclonal antibodies sc-1661 and DO-7, respectively. Of the 11 informative cases, seven (64%) exhibited loss of heterozygosity at least for one marker at 9p21 (p16), whereas no allelic deletions were found for the polymorphic marker at 17p13 (p53). On immunohistochemistry loss of the p16 protein was detected in two of 11 cases. Nuclear staining for p53 protein was found in four of 11 cases. Here, we provide the first evidence of the involvement of the tumor suppressor gene p16 in primary cutaneous large cell lymphoma. Whether p16 deletion in these lymphomas is associated with disease progression and whether this method could serve as an early marker to detect lymphomas at an early stage needs to be addressed in future studies. J Invest Dermatol 115:1104-1107 2000
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PMID:Allelic deletion at 9p21-22 in primary cutaneous CD30(+) large cell lymphoma. 1112 Nov 48

This study investigated gene abnormalities in bladder cancer patients and the relationship between chromosomal alteration and the clinical outcome using microsatellite analysis. A total of 45 human bladder tumor patients were analyzed. The microsatellite markers for 18q21.1 (D18S46, D18S363, and D18S474), 9p21-22 (D9S171, D9S747, D9S1747, and IFNA), and 17p13.1 (TP53) were used for the loss of heterozygosity (LOH) detection. The clinical outcomes were estimated with univariate and multivariate analyses. The results show that patients with LOHs in 18q21.1 and 9p21-22 exhibited a significantly poor prognosis. LOHs of these chromosomal regions had the most predictable potential compared with the other known prognostic factors, such as tumor grade, TNM stage, and age. It is concluded that microsatellite analysis for 18q21.1 and 9p21-22 is capable of predicting the clinical outcome of bladder cancer patients.
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PMID:Microsatellite analysis in multiple chromosomal regions as a prognostic indicator of primary bladder cancer. 1112 6

During the initiation and progression of malignant melanoma, a series of different genetic events accumulate on several different chromosomes. The biological heterogeneity of tumour cells presents a major problem, preventing effective treatment of melanoma. To examine the degree of genetic heterogeneity, we searched for allelic losses (loss of heterozygosity; LOH) on chromosomes 9p, 9q, 1p and 17p, examining different areas within human melanoma metastases. All of the examined metastases were informative within at least one dissected area for at least one marker. Out of 29 areas in 11 melanoma metastases, 58% showed LOH with at least one marker. On chromosome 9p21-22, eight out of 26 informative loci (31%) showed LOH at D9S171 (three not informative), two out of 18 (11%) at IFNA (11 not informative) and seven out of 24 (29%) at D9S169 (five not informative). LOH on chromosome 9q22.3 was examined by the microsatellite marker D9S12; three out of 24 areas (12.5%) showed LOH, and five were not informative. Deletions on chromosome 1p were assessed using D1S450. Four out of 25 (16%) showed LOH; four were not informative. Deletions on chromosome 17p13 were examined with TP53; two out of 21 cases (9%) showed LOH, and eight were not informative. Our data demonstrate an impressive heterogeneity of allelic losses in the investigated chromosomal areas within the same metastatic lesion. This suggests that there is not one specific genetic alteration that accounts for melanoma progression to metastases. Rather there seem to be multiple genetic alterations accumulating even on the same chromosome, and progression from melanoma to metastases is paralleled by the accumulation of clones harbouring multiple genetic abnormalities.
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PMID:Heterogeneity of allelic deletions within melanoma metastases. 1147 23

In the present study, we used 22 microsatellite markers flanking to or within 13 known or candidate tumor suppressor genes (TSGs) to detect loss of heterozygosity (LOH) in these chromosomal regions among 41 cases of non-small cell lung cancer, including 28 squamous cell carcinoma (SCC) and 13 adenocarcinoma (ADC). The studied TSGs comprised FHIT, VHL, APC, PRLTS, p16, IFNA, PTEN, p57, ATM, p53, BRCA1, DPC4 and DCC. Our data demonstrated frequent allelic losses of FHIT, p53, IFNA, VHL and p16 in both SCC and ADC. PTEN and ATM showed the least frequency of LOH, while no deletion of BRCA1 was detected in all tumor samples. LOH analysis of PRLTS was extended to 26 cases of ADC, which demonstrated significantly higher frequency of LOH than SCC. Our data indicated a possible correlation between specific TSG(s) and either histological type of lung cancer, and more attention should be paid to the PRLTS gene, which might play an important role in the development of ADC.
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PMID:Deletion of tumor suppressor genes in Chinese non-small cell lung cancer. 1212 91

In most cases, small-cell carcinoma of the urinary bladder is admixed with other histological types of bladder carcinoma. To understand the pathogenetic relationship between the two tumor types, we analyzed histologically distinct tumor cell populations from the same patient for loss of heterozygosity (LOH) and X chromosome inactivation (in female patients). We examined five polymorphic microsatellite markers located on chromosome 3p25-26 (D3S3050), chromosome 9p21 (IFNA and D9S171), chromosome 9q32-33 (D9S177), and chromosome 17p13 (TP53) in 20 patients with small-cell carcinoma of the urinary bladder and concurrent urothelial carcinoma. DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser-assisted microdissection. A nearly identical pattern of allelic loss was observed in the two tumor types in all cases, with an overall frequency of allelic loss of 90% (18 of 20 cases). Three patients showed different allelic loss patterns in the two tumor types at a single locus; however, the LOH patterns at the remaining loci were identical. Similarly, the same pattern of nonrandom X chromosome inactivation was present in both carcinoma components in the four cases analyzed. Concordant genetic alterations and X chromosome inactivation between small-cell carcinoma and coexisting urothelial carcinoma suggest that both tumor components originate from the same cells in the urothelium.
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PMID:Molecular genetic evidence for a common clonal origin of urinary bladder small cell carcinoma and coexisting urothelial carcinoma. 1585 52


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