UNIPROT:P04637 - FACTA Search

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Query: UNIPROT:P04637 (p53)
77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies using cervical carcinoma cell lines usually show mutated p53 in cases without detectable HPV, and wild-type p53 in cases with detectable HPV. These findings suggest that loss of p53 function, either by mutation or by binding to HPV E6, is required for cervical carcinogenesis. Because mutated p53 is usually detectable immunohistochemically, one would predict an inverse relationship between the presence of HPV and detectable p53. In this study we examined 88 formalin-fixed paraffin-embedded clinical specimens of cervix for the presence of HPV and p53 expression. All cases were studied for the presence of p53 using immunohistochemical methods. The antibody used was mouse monoclonal PAb1801 (Biogenex). The presence of HPV was detected by PCR. Twenty-six specimens showed foci of p53 expression (0/7 normal, 1/8 (13%) condylomas, 1/6 (17%) CIN I, 3/7 (43%) CIN II, 6/20 (30%) CIN III, 13/22 (59%) SCC, 2/5 (40%) adenosquamous carcinomas, and 0/13 adenocarcinomas). p53 expression was more frequent in SCC than with CIN (P = 0.026). HPV was present in 15 of 24 cases with detectable p53 and 22 of 48 cases without detectable p53. No correlation was seen between HPV status and detection of p53. With the exception of one case, p53 expression was seen in less than 10% of cells. p53 expression was not detected in any of the 13 adenocarcinomas examined (P = 0.0016 vs SCC). Our results show that alterations of p53 may play a role in the pathogenesis of cervical squamous carcinoma. However, p53 expression was neither sufficient nor required for cervical carcinogenesis, irrespective of HPV status.
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PMID:Cervical squamous dysplasias and carcinomas with immunodetectable p53 frequently contain HPV. 767 94

Using formalin-fixed and paraffin-embedded cervical tissues, we examined infection with human papillomavirus (HPV) types 16 and 18 by Southern blot analysis following polymerase chain reaction (PCR), and the accumulation of p53 protein by immunohistochemistry in 30 cases of normal or metaplastic cervix, 17 cases of cervical intraepithelial neoplasia grade I (CIN I), 20 cases of CIN II, 37 cases of CIN III and 23 cases of invasive squamous cell carcinoma (ISCC). In addition, we examined the ratio of HPV-infected cells by in situ hybridization (ISH) and the alteration of p53 gene using PCR followed by single-strand conformation polymorphism (PCR-SSCP) in 2 cases of CIN III and 12 cases of ISCC, in which overexpression of p53 was immunohistochemically detected. HPV DNA was detected in 5 cases (16.7%) of normal or metaplastic cervix, 5 cases (29.4%) of CIN I, 9 cases (45.0%) of CIN II, 26 cases (70.3%) of CIN III and 15 cases (65.2%) of ISCC. Positivity for HPV in the groups of CIN III and ISCC was significantly higher than in the normal or metaplastic cervix (P < 0.05). The accumulation of p53 was not detected in the normal or metaplastic cervix, CIN I and CIN II. High-level p53 accumulation was identified in basal and suprabasal atypical cells in 27.0% (10/37) of CIN III and in carcinoma cells in 43.5% (10/23) of ISCC cases, and low-level accumulation was identified in atypical cells of 35.1% (13/37) of CIN III and in carcinoma cells in 30.4% (7/23) of ISCC cases. The accumulation of p53 was found to coexist with infection by HPV in 17 (46.0%) of 37 CIN III cases and 12 (52.2%) of 23 ISCC cases, and high-level p53 accumulation was more frequently detected in HPV-positive ISCC cases. Either HPV infection or accumulation of p53 was found in 16.7% (5/30) of the cases of normal or metaplastic cervix, 29.4% (5/17) of CIN I, 45.0% (9/20) of CIN II, 86.5% (32/37) of CIN III and 87.0% (20/23) of ISCC cases. These results suggest that the inactivation of p53 function by HPV infection or alteration of p53 protein itself precedes the development of tumours with a fully malignant and invasive phenotype and plays an important role in tumorigenesis in the uterine cervix. ISH study provided no correlation between the degree of immunohistochemical positivity for p53 and the ratio of HPV-positive cells in the same lesions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Immunohistochemical detection of p53 in cervical epithelial lesions with or without infection of human papillomavirus types 16 and 18. 769 16

Recent data suggest an inverse correlation between human papillomavirus (HPV) infection and p53 tumor-suppressor gene mutation. In an attempt to elucidate the role of p53 mutations in cervical neoplasias, 65 cervical lesions, ranging from normal to malignant, were examined for overexpression of p53 protein by immunohistochemistry in paraffin-embedded tissue, and correlated with proliferating cell nuclear antigen (PCNA). An overexpression was seen in 35% of well-differentiated and 32.5% of poorly-differentiated squamous carcinomas, in 43.33% of microinvasive and 21.66% of CIS. More than 50% of neoplastic cells were immunoreactive for p53 protein in 10% of well-differentiated squamous carcinomas. Other positive specimens showed reactivity in < 24% of tumor cells. No staining was found in adenocarcinoma, dysplastic tissue, condylomas and normal tissue (83.07%). In contrast PCNA was detected in all cases of invasive squamous carcinomas, adenocarcinoma, CIS, CIN III, in 32.5% of CIN II, in 29.54% CIN I, and in 53.52% of wart. More than 50% of tumor cells showed nuclear staining for PCNA protein in 61.17% of invasive squamous carcinomas, in 21.66% of CIS, in 39% CIN III, in 32.5% CIN II and in 7.64% of wart. In the remain cases the positivity of nuclear staining was < 24%. No staining was present in 20% of cases including in normal cervix. Our data suggest that the viral-host protein interactions result in loss of the negative growth control normally exerted by p53. The consequence of HPV infection is a loss of functional wild-type p53 protein within the cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunohistochemical analysis of p53 oncoprotein and proliferating cell nuclear antigen (PCNA) in the cervix uteri. 791 Jan 35

High-risk human papillomavirus (HPV) is a known risk factor in the etiology of cervical intraepithelial neoplasia (CIN) I-III and invasive cervical carcinoma (ICC). The most severe preinvasive lesion is CIN III, and it is still not entirely understood why some cases progress to invasion, whereas others do not. Our hypothesis that this could be predicted by intratype variation of the immortalizing and transforming early proteins E6 and E7 was tested. Because HPV16 is frequently detected in cervical neoplastic lesions, 25 CIN III and 17 ICC cases from Swedish women, all positive for this genotype, were selected to investigate the E6 and E7 genes for mutations. PCR-amplified products were sequenced by the fluorescent dideoxy termination method. ICC harbored almost exclusively HPV16 E6 variants (94%) and rarely harbored the prototype (6%), whereas CIN III demonstrated a more uniform distribution of variants (56%) and prototype (44%; P = 0.013). All variants contained variations that were identified in areas likely to be important for protein-protein interaction with p53 or in areas of immunological significance. The most frequent E6 variation was seen at residue 83. This polymorphism was detected alone or in combination with others in 88% of ICC and 44% of CIN III cases. E7 variations were extremely rare and were only detected together with E6 variations in 4% of CIN III and in 6% of ICC cases, suggesting that the HPV16 E7 but not the HPV16 E6 oncoprotein is highly conserved in vivo. This indicates that HPV16 E6 variants, specifically those containing the substitution at residue 83, may be more oncogenic than the prototype and thus carry a higher risk for the development of invasive cervical disease. This may be due to subtle differences in the type of transformation produced or to evasion of host immune defenses. These results might have implications for future in vitro studies, diagnostics, treatment, and vaccine design.
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PMID:Human papillomavirus 16 E6 variants are more prevalent in invasive cervical carcinoma than the prototype. 948 42

Early epidemiological studies of cervical neoplasia suggested a causal relation with sexual activity and human papillomaviruses (HPVs) have emerged as prime suspects as venerally transmitted carcinogens. HPVs fall into two broad camps: low risk types, associated with cervical condylomas and CIN 1; and high risk types (mostly 16 and 18), found in 50-80% of CIN 2 and CIN 3 lesions, and 90% of cancers. This association with cancer is very strong, with odds ratios of > 15 (often much higher) in case-control studies that are methodologically sound. An infrequently detected third group of intermediate risk type HPVs is associated with all grades of CIN and occasionally with cancers. HPVs have also been detected in a wide range of asymptomatic controls, indicating that other events are required for development of neoplasia such as viral persistence and/or altered expression of viral genes, often following integration of the viral genome. This leaves the two major viral oncogenes, E6 and E7, directly coupled to viral enhancers and promoters, allowing their continued expression after integration. High risk HPV E7 proteins bind and inactivate the Rb protein, whereas E6 proteins bind p53 and direct its rapid degradation. A range of putative cofactors has been implicated in progression: HLA type, immunosuppression, sex steroid hormones, and smoking; most of these cofactors appear to influence progression to CIN 3. The natural history includes progression to CIN 3 in 10% of CIN 1 and 20% of CIN 2 cases, whereas at least 12% of CIN 3 cases progress to invasive carcinoma. Cervical glandular intraepithelial neoplasia (CGIN) often coexists with squamous CIN, and the premalignant potential of high grade CGIN is not in doubt, but the natural history of low grade CGIN remains uncertain. A high proportion of CGIN lesions and adenocarcinomas are HPV positive, and HPV18 has been implicated more in glandular than in squamous lesions. A strong clinical case for the application of HPV typing of cells recovered from cervical scrapes can be made; however, a rigorous cost-benefit analysis of introducing HPV typing into the cervical screening programme is required. Prophylactic and therapeutic HPV vaccines are under development. This article reviews the aetiology, pathogenesis, and pathology of cervical neoplasia, emphasising the role of HPVs.
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PMID:Aetiology, pathogenesis, and pathology of cervical neoplasia. 960 80

Human papillomavirus (HPV) 16 has previously been found in 19/41 breast carcinomas (46%) in women with a history of HPV 16 positive CIN III lesions. There was no significant difference in distribution of histological subtypes, mean or median tumour diameter or number of regional lymph node metastases in the HPV positive and HPV negative breast carcinoma groups. P53, p21 and c-erbB-2 proteins were analysed by immunohistochemistry in the HPV 16 positive and HPV negative breast carcinomas. There was a significant difference in p53 and p21 protein immunoreactivity between HPV 16 positive and HPV negative breast carcinomas (p = 0.0091 and p = 0.0040), with a significant less detectable p53 and p21 protein immunoreactivity in the HPV 16 positive cases. There was also a significant difference in the coexpression of p53/p21 between the HPV 16 positive and HPV 16 negative breast carcinomas (p = 0.002). No significant difference in immunostaining for c-erbB-2 protein in the two groups was found (p = 0.15), or for the coexpression of p53/c-erbB-2 (p = 0.19). The significantly lower expression of p53 and p21 proteins in HPV 16 positive than in HPV 16 negative breast carcinomas supports the hypothesis of inactivation and degradation of wild-type p53 proteins by HPV 16 E6 and that p53 mutation is not necessary for transformation in the HPV 16 positive cases.
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PMID:Significant difference in p53 and p21 protein immunoreactivity in HPV 16 positive and HPV negative breast carcinomas. 1060 22

This study aimed to assess the role of specific human papillomavirus type 16 (HPV-16) variants, in combination with p53 codon 72 polymorphism genotypes, in cervical carcinogenesis. An initial sequence analysis of HPV-16 long control, E6 and E7 regions of 53 well-defined cervical samples containing HPV-16 revealed that a T to G transition at nucleotide position 350 within the E6 open reading frame was the most common variation, the frequency of which seemed to decrease with increasing severity of the lesion. Therefore, a total of 246 cervical samples of residents of The Netherlands was specifically analysed for HPV-16 350G/T variants and/or p53 codon 72 genotypes. These comprised HPV-negative normal cervical scrapes (n=40), normal cervical scrapes containing HPV-16 (n=46), scrapes containing HPV-16 from women with abnormal cervical cytology participating in a non-intervention follow-up study without (n=38) and with (n=51) a histologically proven cervical intraepithelial neoplasia (CIN) III lesion at the end of the study, and cervical squamous cell carcinomas (n=71). Neither specific HPV-16 350G/T variants nor specific p53 genotypes were associated with a higher risk of developing CIN III or cervical cancer. However, HPV-16 350T variants were significantly over-represented in p53 Arg homozygous women with cervical cancer. This suggests that, in p53 Arg/Arg women, infection with HPV-16 350T variants confers a higher risk of cervical cancer.
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PMID:Analysis of human papillomavirus type 16 E6 variants in relation to p53 codon 72 polymorphism genotypes in cervical carcinogenesis. 1064 29

The incidence of cervical neoplasia in Israeli Jewish women is persistently lower, while that of vulvar carcinoma is comparable to that in other populations. The aim of the present investigation was to assess the prevalence of HPV and of immunohistochemically detected mutant p53 in Israeli Jewish women with cervical and vulvar neoplasia compared with other populations. Tissue sections from formalin-fixed paraffin-embedded blocks of ten patients with CIN III, 29 with invasive squamous cell carcinoma, three with adenocarcinoma and 14 with invasive vulvar carcinoma, were examined for the presence of HPV 16 and HPV 18 DNA by PCR amplification, and for mutant p53 protein by immunohistochemical staining. HPV negative cases were re-examined with a sensitive primer. HPV DNA was detected in eight patients with CIN III and in 23 patients with invasive squamous carcinoma. In the remaining cervical squamous neoplasia tissue analysis with the sensitive primer could not be done. HPV DNA was also detected in two patients with adenocarcinoma and in nine (64.2%) patients with vulvar carcinoma. Positive p53 immunohistochemical staining was found only in one CIN III patient, in six (20.7%) squamous carcinoma and in 11 (78.6%) vulvar carcinoma patients. Of the p53 immunohistochemical staining positive tissues, two with cervical carcinoma and six with vulvar carcinoma were also HPV-positive. The prevalence of HPV and of positive p53 immunohistochemical staining in our series of Israeli Jewish women with cervical and vulvar neoplasia is similar to that in other populations, suggesting that the etiological factors are probably also alike.
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PMID:The presence of HPV 16, 18 and p53 immunohistochemical staining in tumor tissue of Israeli Jewish women with cervical and vulvar neoplasia. 1072 15

Loss of p53 function has been implicated in a wide variety of human malignacies. Many studies suggest that in cervical carcinoma p53 function is inactivated either by gene mutation or by complex formation with E6 oncoprotein product of high-risk human papillomavirus (HPV). The aim of this study was to determine the status of HPV infection and p53 gene mutation as well as their correlation in cervical carcinomas. Formalin-fixed paraffin-embedded tissues of 12 cervicitis, 21 cervical intraepithelial neoplasia grade 3 (CIN 3) and 17 squamous cell carcinomas were determined for the presence of HPV using polymerase chain reaction (PCR) amplification and dot blot hybridization. The status of p53 mutations in exons 5-8 was evaluated by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) and confirmed by direct nucleotide sequencing. HPV infections were detected in all CIN 3 and squamous cell carcinomas (100%). Mutations of p53 were present in 3 of 38 HPV-positive samples: one with an ATG-->TTG transversion (Met-->Leu) in codon 237 of exon 7; and the others with a TGC-->TGG transversion (Cys-->Trp) in codon 242 of exon 7, and a CGT-->CCT transversion (Arg-->Pro) in codon 273 of exon 8, respectively. Our findings show that the frequency of p53 mutation is low in primary cervical carcinoma and that the p53 gene mutation and HPV infection are not mutually exclusive events in the development of cervical cancer. Thus, other genetic events independent of p53 inactivation may also significantly contribute to the carcinogenesis of the uterine cervix.
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PMID:p53 status and human papillomavirus infection in Thai women with cervical carcinoma. 1102 67

DNA replication and centrosome duplication have to be strictly synchronized to guarantee genomic stability. p53, pRb, cyclin E, and cyclin A are reported to be involved in the synchronizing process. We investigated the relationship between papillomavirus infection, centrosome aberration and aneuploidy during genesis of cervical carcinoma. The number of centrosomes found in cells from normal cervical epithelium (n = 5), condyloma acuminata (n = 5), cervical intraepithelial neoplasia (CIN) I, II, and III (n = 14) and invasive cervical carcinoma (n = 5) was analyzed by gamma tubulin immunofluorescence staining. The nuclear DNA content was investigated by image cytometry and human papillomavirus (HPV) infection was determined by polymerase chain reaction. Normal epithelia and condyloma acuminata showed cells with one or two centrosomes, whereas CIN lesions showed cells with an increasing number of centrosomes. This abnormality was found to be lowest in CIN I lesions, increased with advancing grade of CIN and was highest in lesions of invasive carcinomas. In parallel, an increasing number of cells with aberrant DNA content was seen. All carcinomas and all except one of the CIN III lesions showed aneuploidy. Three CIN II cases were aneuploid and two cases with CIN I were tetraploid. Normal epithelia and condyloma acuminata showed diploidy. All invasive carcinomas and lesions with CIN were positive for high-risk HPV types 16, 18, or 31, except one invasive carcinoma and one CIN II lesion positive for universal primers only. Three condyloma acuminata were HPV 16-positive and one HPV 6-positive. The results suggest that high-risk HPV infection is correlated to a progressive numerical disturbance of centrosome replication followed by progressive chromosomal aberrations in CIN lesions and invasive carcinomas.
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PMID:Human papillomavirus infection, centrosome aberration, and genetic stability in cervical lesions. 1130 43

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