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 single, exophytic, cutaneous tumor on the thigh of a 52-year-old man was examined by light microscopy, in situ hybridization and immunohistochemistry. It demonstrated distinct areas of verruca and of seborrheic keratosis-like morphology simultaneously. Focally, architectural abnormalities were noted in some deeper parts of the tumor, but there was no morphological evidence of malignancy. The patient has remained disease-free for two and a half years after surgery. Biotinylated full genomicDNA probes of HPV confirmed the presence of types 6/11 exclusively in the verrucous portion of the neoplasm. In the verrucous component p53 protein was overexpressed and, additionally, increased Ki-67 immunopositive signals were detected, being localized below the HPV-DNA-expressing spinous cells.
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PMID:A solitary cutaneous tumor with distinct areas of verruca and seborrheic keratosis-like lesion. 1060 30

Renal transplant recipients are prone to numerous benign and malignant skin lesions. Previous work in the authors' laboratory has determined that the human papillomavirus may be the viral aetiology of these skin lesions. The p53 tumor-suppressor gene is the most frequently mutated gene in a wide range of human cancers. Here the authors describe an immunohistochemical study to evaluate the expression of p53 in benign and malignant skin lesions from renal transplant recipients and immunocompetent patients with skin cancer. The effect of p53 mutations on the expression patterns observed were examined by polymerase chain reaction-single strand conformation polymorphism analysis and direct cycle sequencing. The expression of the p53-regulated cyclin-dependant kinase inhibitor p21Waf1/Cip1 and Mdm2 was also examined in p53-positive cells. The expression of p53 in benign and malignant lesions was found to be markedly different. p53 was expressed in only 40% (6/15) of viral warts analyzed. The expression was confined to the basal layer both in the lesion and in adjacent normal skin, and the level of expression was low and only in a small number of cells (<10%). Of the cutaneous squamous cell carcinomas analyzed, 60% (9/15) showed p53 expression. Two different patterns of expression were observed. Basal layer expression in both the invasive tumor and adjacent normal skin was observed in 50% of the p53-positive squamous cell carcinomas; in the remaining 50%, p53 was expressed diffusely throughout the invasive tumor and in the basal layer of adjacent normal skin. The level of expression was high and in a large number of cells. Polymerase chain reaction-single strand conformation polymorphism analysis revealed that only one of the squamous cell carcinomas expressing p53 harbored a p53 mutation and that the accumulated p53 in the remaining tumors was wild type. No Mdm2 or p21Waf1/Cip1 expression was detected in the p53-positive squamous cell carcinomas, indicating that although the accumulated p53 is stable, it does not function effectively as a transcriptional activator. This represents a novel p53 phenotype in cutaneous squamous cell carcinoma. In addition, no correlation was seen between the presence and absence of human papillomavirus and p53 expression.
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PMID:Altered p53 expression in benign and malignant skin lesions from renal transplant recipients and immunocompetent patients with skin cancer: correlation with human papillomaviruses? 1155 22

Human papillomavirus (HPV) infects the squamous epithelial cells of oral cavity and cervix leading to formation of warts that develops into the cancer. Human papillomavirus (HPV)-16 and 18 encode E6 oncoprotein, which binds to and induces degradation of the tumour suppressor protein p53. A common polymorphism of p53, encoding either proline (Pro) or arginine (Arg) at position 72, affects the susceptibility of p53 to E6 mediated degradation in vivo. Oral cancer is a pressing problem in India due to the widespread habit of chewing betel quid, which plays an important role in etiology of this disease. In the present study an attempt has been made to analyze the genetic predisposition of the Indian population to HPV infection and oral carcinogenesis. In our study a total of 110 cases of Oral Cancer highly addicted to betel quid and tobacco chewing are analyzed for HPV 16/18 infection and its association with polymorphism at p53 codon 72. Of these a total number of 37 patients (33.6%) have shown the presence of HPV, among which the presence of HPV-16, 18 and 16/18 coinfection is 22.7%, 14.5% and 10%, respectively. Our results also indicate that the p53 codon 72 genotype frequencies in Indian Oral Cancer patients are 0.55 (Arg) and 0.45 (Pro) as per Hardy-Weinberg equilibrium. In our study, striking reduction in Pro/Pro allele frequency has been found in HPV positive cases, indicating Arg/Arg genotype to be more susceptible to HPV infection and oral carcinogenesis.
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PMID:Prevalence of high-risk human papilloma virus types and its association with P53 codon 72 polymorphism in tobacco addicted oral squamous cell carcinoma (OSCC) patients of Eastern India. 1180 92

Chronic ulcerative stomatitis protein (CUSP), the most abundant cutaneous isoform of p63, is a p53-related gene essential for epithelial development. CUSP lacks the N-terminal transactivation domain found on other p53 family members and has been shown to inhibit p53 function in vitro. In this study, biopsies of normal skin (21 of 21), benign neoplasms [seborrheic keratosis (3 of 3), acrochordon (2 of 3), and verruca plana (3 of 3)], and squamous cell carcinomas (SCC) (4 of 4) displayed strong nuclear CUSP immuno-reactivity in epidermal cells. In contrast few basal cell carcinomas (BCC) (7 of 27) and sebaceous nevi (1 of 2) displayed this pattern of CUSP immunoreactivity. Thus, biopsies of cutaneous conditions characterized by sonic hedgehog (SHH) pathway dysregulation were more than 86 times as likely to lack CUSP/p63 immunofluorescence as were other cutaneous samples. Adjacent normal-appearing skin from patients with basal cell nevus syndrome (BCNS) (2 of 3) also lacked CUSP immuno-staining. Lastly, a BCC arising in a patched heterozygous mouse also lacked CUSP immuno-staining. Because CUSP mRNA and protein were detected via Northern and Western analysis in BCC samples lacking CUSP immuno-staining, we sequenced the coding region of CUSP from two non-staining BCCs but found no mutations. Therefore, CUSP appears to be present, unmutated, and yet frequently undetectable by immunofluorescence in cutaneous lesions in both humans and mice that are associated with SHH pathway dysregulation (BCCs, BCNS, and nevus sebaceous).
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PMID:CUSP/p63 expression in basal cell carcinoma. 1210 58

We showed that transposon P(GUS.p53.259H), mapped to chromosome 3 and carrying a dominant mutation p53(259)H.GUS, has a positive effect on the frequency of spontaneous and carcinogen-induced tumor mosaic clones warts- in Drosopila melanogaster heterozygotes for the tumor suppressor gene warts located in the same chromosome. The transposon effect could be explained either by the arrest of apoptosis in the cells expressing mutant p53(259)H.GUS gene and containing carcinogen-induced pre-mutations, and/or by genetic instability introduced into chromosome 3 by the P(GUS.p53.259H) transposon itself. The effect of the P(GUS.p53.259H) appeared to be carcinogen-specific. It substantially increased the frequency of tumors induced by supermutagenic platinum complex, oxoplatin, and did not increase the frequencies of tumors induced by polycyclic aromatic hydrocarbons, benzo(alpha)pyrene and pyrene. In the spectrum of mutations induced by all carcinogens tested, somatic recombination events prevailed over somatic mutations. Hence, carcinogen-specificity of the P(GUS.p53.259H) effect cannot be explained by preferential induction of somatic mutations or somatic recombination by one of the carcinogens. Organ-specificity of the increased frequency of mosaic warts- clones induced by P(GUS.p53.259H) was established.
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PMID:[The effect of transposon P(GUS . p53.259H)on the frequency of tumor clones in Drosophila melanogaster wtsp2/+ heterozygotes]. 1217 85

Human papillomaviruses (HPVs) are small DNA tumor viruses that are the causative agent of warts and are associated with many anogenital cancers. The viral gene encoding the E6 protein has been found to be involved in HPV oncogenesis. E6 is known to inactivate the cellular tumor suppressor, p53. In addition, E6 has been shown to bind to a variety of other cellular proteins. The focus of this study was to determine what role the interactions of E6 with a subset of cellular proteins which contain a common alpha-helical domain in their E6 binding region (alpha-helix partners) play in E6-mediated phenotypes. We generated transgenic mice expressing a mutant of E6, E6(I128T), which is defective for binding at least a subset of the alpha-helix partners, including E6AP, the ubiquitin ligase that mediates E6-dependent degradation of the p53 protein, to determine whether binding of alpha-helix partners plays a role in E6-mediated activities in vivo. Unlike mice expressing the wild-type E6 (strain K14E6(WT)), the mice expressing E6(I128T) lacked the ability to alter the radiation-induced block to DNA synthesis and promote the formation of benign skin tumors in conjunction with chemical carcinogens. Additionally, they displayed reduced levels of skin hyperplasia, spontaneous skin tumors, and tumor progression activity compared to those of the K14E6(WT) mice. From these results, we conclude that a domain in E6 that mediates alpha-helix partner binding is critical for E6-induced phenotypes in transgenic mice.
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PMID:A mutant of human papillomavirus type 16 E6 deficient in binding alpha-helix partners displays reduced oncogenic potential in vivo. 1243 30

The most frequent form of neoplasia in the oral cavity is the squamous cell carcinoma (about 90% of cases) representing the 3-5% of all malignant tumors with about 56% of mortality rate, at 5 years from the diagnosis. In general, the neoplastic disease is now unanimly considered as a multifactorial and multiphasic pathology. Multiphasic since the carcinogenic process consists in the cellular capacity to acquire oncological potentialities through several stages such as: moltiplication (a), transmission (b) of malignity caracteristics to progenic cells, invasivity (c), capacity to give metastasis (d) and also resistance to chemiotherapy. Multifactorial since in the onset of the disease intrinsic and extrinsic factors are certainly involved. In the carcinogenic process of CCS a high percentage has been noticed of loss of heterozygosity (LOH) in the short arm (P) of cromosoms 3 and 9, which contains the tumor-suppressor genes p53 and DDC (Deleted in colon rectal cancer). In the onset of VADS carcinoma and in particular of oral CCS, it has also been formulated the hypothesis of an intrinsic genetic factor (Llewellyn et al., 2001) between patients, also young, who present the neoplasia even trough they have never been exposed to extrinsic risk factors such as smoke and alcohol. Since part of patients with oral CCS do not always refer a common risk factors history as possible extrinsic neoplasia causes, it has been formulated the hypothesis that some viral infections, for their oncogenic capacity, could be the main ethiological factors predisposing to this neoplasia. The HPV are responsible, either in the oral cavity or on the epidermis, for benign proliferations such as: Verruca Vulgaris, Condyloma Acuminatum, Focal Epithelial Hyperplasia, Squamous Cell Papillomas, but also lesions that are potentially or certainly malignant such as CCS and Verrucous Carcinoma. The molecular analysis performed show that proteins produced from E6 and E7 portions of viral genoma (HPV 16-18) interfer and degrade proteins p53 and pRb produced by tumor suppressor genes (TSg). Recently, thanks to new molecular biology techniques, several authors are studying potentially neoplastic lesions, in order to better understand the association with HPV.
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PMID:[Soft tissue pathologies of the oral cavity]. 1268 15

Human papillomaviruses (HPVs) are the causative agent of warts. Infections with high-risk HPVs are associated with anogenital and head and neck cancers. One of the viral genes responsible for HPV's oncogenic activity is E6. Mice expressing the HPV-16 E6 protein in their epidermis (K14E6(WT)) develop epithelial hyperplasia and squamous carcinomas. Numerous cellular proteins interact with E6, some of which can be grouped based on common amino acid motifs in their E6-binding domains. One such group, the PDZ partners, including hDLG, hSCRIBBLE, MUPP1, and MAGI, bind to the carboxy-terminal four amino acids of E6 through their PDZ domains. E6's interaction with the PDZ partners leads to their degradation. Additionally, E6's binding to PDZ proteins has been correlated with its ability to transform baby rat kidney cells in tissue culture and to confer tumorigenicity onto cells in xenograft experiments. To address whether the ability of E6 to bind PDZ domain partners is necessary for E6 to confer epithelial hyperproliferation in vivo, we generated transgenic mice that express in stratified squamous epithelia a mutant of E6 lacking the last six amino acids at its carboxyl terminus, E6(Delta 146-151), from the human keratin 14 (K14) promoter. The K14E6(Delta 146-151) mice exhibit a radiation response similar to that of the K14E6(WT) mice, demonstrating that this protein, as predicted, retains an ability to inactivate p53. However, the K14E6(Delta 146-151) mice fail to display epithelial hyperplasia. These results indicate that an interaction of E6 with PDZ partners is necessary for its induction of epithelial hyperplasia.
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PMID:The PDZ ligand domain of the human papillomavirus type 16 E6 protein is required for E6's induction of epithelial hyperplasia in vivo. 1276 14

Defects in chromosomes or mitotic spindles activate the spindle checkpoint, resulting in cell cycle arrest at prometaphase. The prolonged activation of spindle checkpoint generally leads to mitotic exit without segregation after a transient mitotic arrest and the consequent formation of tetraploid G(1) cells. These tetraploid cells are usually blocked to enter the subsequent S phase by the activation of p53/pRb pathway, which is referred to as the G(1) tetraploidy checkpoint. A human homologue of the Drosophila warts tumor suppressor, WARTS, is an evolutionarily conserved serine-threonine kinase and implicated in development of human tumors. We previously showed that WARTS plays a crucial role in controlling mitotic progression by forming a regulatory complex with zyxin, a regulator of actin filament assembly, on mitotic apparatus. However, when WARTS is activated during cell cycle and how the loss of WARTS function leads to tumorigenesis have not been elucidated. Here we show that WARTS is activated during mitosis in mammalian cells, and that overexpression of a kinase-inactive WARTS in Rat1 fibroblasts significantly induced mitotic delay. This delay resulted from prolonged activation of the spindle assembly checkpoint and was frequently followed by mitotic slippage and the development of tetraploidy. The resulting tetraploid cells then abrogated the G(1) tetraploidy checkpoint and entered S phase to achieve a DNA content of 8N. This impairment of G(1) tetraploidy checkpoint was caused as a consequence of failure to induce p53 expression by expressing a kinase-inactive WARTS. WARTS thus plays a critical role in maintenance of ploidy through its actions in both mitotic progression and the G(1) tetraploidy checkpoint.
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PMID:Tumor suppressor WARTS ensures genomic integrity by regulating both mitotic progression and G1 tetraploidy checkpoint function. 1512 20

HPV belongs to a family of tumorigenic viruses and induces cutaneous and mucosal proliferation of epithelial cells (papillomas, condylomas, warts). The abnormality accumulation of p53 protein appears to be a common step in the development of many human cancers and has been frequently reports in human cancers including head and neck. The aim of this study was to examine HPV infection incidents and p53 alteration in oral papillomas. HPV was detected by PCR, p53 accumulation by immunohistochemical detection. The overexpression of p53 was revealed in 20 cases (55%) out of 36 papillomas. We found p53 overexpression in 8 out of 13 HPV positive papillomas (61.5%) and in 12 out of 23 HPV negative papillomas (52%). Our findings indicate that HPV infection and/or changes in p53 protein coexist in oral cavity papillomas.
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PMID:Presences of human papillomavirus DNA (HPV) and immunohistochemical p53 overexpression in papillomas of oral cavity. 1563 89


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