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)

Altered angiogenic response is associated with high-grade cervical dysplasia and with invasive squamous carcinoma of the cervix. Vascular Endothelial Growth Factor (VEGF) is one of the most potent inducers of angiogenesis and is up-regulated in carcinoma of the cervix. Infection by high-risk human papillomavirus and persistent expression of viral oncogene E6 are etiologically linked to the development of cervical cancer. E6 is able to immortalize cells and induce malignant transformation by inactivating p53. In cervical cancer, regulation of VEGF expression is poorly described. Thus, we investigated whether E6 oncoprotein could regulate VEGF expression in HPV18-positive cervical cancer-derived HeLa cells harboring a wild-type p53. The alternative splicing of vegf mRNA renders three major isoforms of 121, 165 and 189 amino-acids in humans. We have designed isoform specific real time QRT-PCR assays to quantitate vegf transcripts and VEGF121 was the predominant isoform. Silencing HPV18 E6 mRNA with specific siRNA reduced VEGF121 expression by at least 50% whereas silencing of p53 did not alter its expression. Treatment with cycloheximide did not inhibit E6-induced VEGF121 expression. Collectively, these results suggest that HPV18 E6 oncoprotein contributes to tumor angiogenesis by inducing VEGF transcription from the promoter in a p53-independent manner.
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PMID:The human papillomavirus type 18 E6 oncoprotein induces Vascular Endothelial Growth Factor 121 (VEGF121) transcription from the promoter through a p53-independent mechanism. 1767 92

Studies in cervical dysplasia have reported overexpression of the tumour suppressors p14 and p16 - and absence of p53 - in high-risk human papilloma virus (HPV)- associated lesions. In skin carcinogenesis, the relation between these tumour suppressors and HPV remain unclear. We evaluated the expression of the tumour suppressors p14, p16 and p53 in pre-malignant and malignant squamous skin tumours, and its relation with risk factors for skin carcinogenesis (HPV, immune status and sun exposure). We performed immunohistochemical stainings for p14, p16 and p53 on paraffin embedded material of 71 pre-malignant squamous skin lesions and 34 squamous cell carcinomas, from 52 renal transplant recipients (RTRs) and 53 immunocompetent individuals. PCR-based assays were used for detection and genotyping of beta-papilloma virus (beta-PV) types and mucosal HPV types. P14 expression was independent of the expression of p16 and p53, irrespective of immune status and skin site. In 49 of 105 specimens (46.6%), one or more beta-PV types were detected. We found no significant association between p14, p16 or p53 protein expression and overall presence of beta-PV, irrespective of immune status. There was a significant association between presence of beta-PV and lesions from sun-exposed skin sites in the RTRs (P = 0.002). We conclude that in skin carcinogenesis, relations between the herein studied tumour suppressors and HPV are different from what one would expect based on findings in cervical neoplasia. P14, p16 and p53 expressions are independent of immune status. Our data indicate that in immunosuppressed patients, beta-PV together with ultraviolet radiation act synergetic in promoting carcinogenesis.
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PMID:Expression of p14ARF, p16INK4a and p53 in relation to HPV in (pre-)malignant squamous skin tumours. 1868 9

This study was conducted to assess the predictive value of p-glycoprotein (p-gp) and p53 immunoexpression in human papillomavirus (HPV) infected cases of cervical dysplasia. Expression of both p-gp and p53 proteins was detected in cervical smears from 177 squamous intraepithelial lesions (SIL) cases along with 183 "atypical squamous cells of unknown significance" (ASCUS) and 150 normal cases. HPV 16 and 18 infection was detected by polymerase chain reaction using type-specific primers for HPV sub-types. There were no significant detectable p53 and p-gp expression in the normal cervix smears (p>0.05). In the ASCUS group 10 cases were positive for both p53 and p-gp immunoreactivity. In cervical dysplasia cases, p53 was positive in 86 (48.58%) while p-gp was positive in 93 (52.54%) and the two markers showed a highly significant correlation (r=0.92, p<0.001). Expression of p53 and p-gp was associated with grade of SIL (p<0.001). A positive correlation between the presence of HPV and expression of proteins p53 and p-gp in smears of patients with cervical lesions was also noted (p<0.001). Thus, p53 and p-gp immunostaining in cervical smears may act as an auxiliary biomarker for detection of HPV-associated cervical lesions. Additionally, a significant positive correlation between ascending grades of SIL and labeling indices of markers suggests that p53 and p-gp can be used as an adjunct to cytomorphological interpretation of conventional cervical Pap smears.
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PMID:Expression of P-glycoprotein is positively correlated with p53 in human papilloma virus induced squamous intraepithelial lesions of uterine cervix: poor prognosis association. 2346


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