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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

In this study we investigated the number of blood vessels and vascular proliferation in subepithelial areas of 80 cervical condylomas and cervical intraepithelial neoplasias (CIN). The number of blood vessels was determined by counting factor VIIIRAg-positive vascular channels in areas beneath the epithelial lesions. Vascular proliferation was evaluated by determining the number of proliferating cell nuclear antigen (PCNA)-positive endothelial cells in the subepithelial connective tissues. The results were compared with the expression of human papillomavirus (HPV) DNA subgroups (6/11 (low-risk) and 16/18/31/33/35 (high-risk) of the lesions, as determined by dot-blot and in situ hybridization, and with epithelial cell proliferation as determined by immunohistochemistry for PCNA. Also p53 immunohistochemistry of the lesions was performed. Even though CIN II-III lesions on average contained more factor VIIIRAg-positive blood vessels compared to condylomas and CIN I lesions, no significant association was found between their number and the degree of dysplasia. However, moderate or strong PCNA staining in vascular endothelial cells was seen significantly more often in CIN II-III lesions than in condylomas and CIN I lesions (p = 0.008): 34/80 (45%) cases contained detectable HPV DNA as determined by dot-blot or in situ hybridization. There was no correlation between the presence or absence of HPV DNA and the number of PCNA-positive endothelial cells. Nine cases showed p53-positive cell nuclei and in three cases there was more than 1% positive nuclei in the lesion. No association was found between the vascularity or the number of PCNA-positive endothelial cells and the p53 immunoreactivity. The increased proliferative activity of endothelial cells in CIN II-III lesions suggests that they are angiogenically more active than condylomas and CIN I lesions. This activity does not, however, depend on the HPV or p53 status. This is the first report in which endothelial cell PCNA positivity was used as a marker for vascular proliferation.
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PMID:The association of vascular proliferation with HPV status and epithelial PCNA positivity in cervical intraepithelial lesions. 861 Nov 92

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

The relationship between human papillomavirus (HPV) infection and cell cycle regulators p53, MDM2, and p21 in cervical intraepithelial neoplasia (CIN) has not been investigated. p53, MDM2, and p21 immunoreactivity were analyzed with respect to HPV DNA status in high-grade CIN (CIN II-III). Formalin-fixed, paraffin-embedded tissue sections from 169 biopsy specimens with high-grade CIN were examined for HPV DNA by polymerase chain reaction with the L1 and E1 consensus primers Gp5+/6+ and CpI/CpIIG. HPV-positive specimens were typed with the E6 type-specific primers for HPV 16 and 18. The biopsy specimens were stained with the monoclonal antibodies p53, MDM2, and p21. The interpretation of nuclear staining was regarded as focal (< 5%), regional (5% to 50%), or diffuse (> 50%). HPV DNA was found in 156 cases (92%); 122 (78%) were positive for HPV 16, 18, or both. Immunohistochemically, p53 was detected in 50 specimens (30%); nuclear staining was mainly focal. Focal nuclear staining for MDM2 was found in 6 specimens (4%), and regional and diffuse nuclear staining for p21 was present in 137 (81%). Significant correlation was found only between p53 and MDM2 immunoreactivity. These results indicate that there is no correlation between HPV status and expression of the cell cycle regulators p53, MDM2, and p21. Inactivation of p21 and p53 protein may be important, and MDM2 abnormalities seem to play a minor role in the development of high-grade CIN.
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PMID:Expression of p53, MDM2, and p21 proteins in high-grade cervical intraepithelial neoplasia and relationship to human papillomavirus infection. 989 Dec 36

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

In order to assess further biological evidence for similarities among the "diagnostic classes" of cervical lesions, which are now a matter of international discussion in the search for a uniform classification, the purpose of this study was to characterize the immunoexpression of cell proliferation markers (proliferating cell nuclear antigen, PCNA and Ki-67) and protein p53. Each marker was individually quantified in basal, intermediate, and superficial epithelial compartments presenting chronic cervicitis (CC) accompanied by the cytopathic effects of infection by human papillomavirus (CCHPV) or not (CC), as well as in cervical intraepithelial neoplasia (CIN) grades I, II, and III. A total of 100 patients were evaluated and the positive nuclei were counted separately, including all extensions of the available epithelium. The percentage of PCNA- and Ki-67-positive cells increased with increasing grade of the cervical lesions, although PCNA immunoreactivity was always greater than the immunoreactivity observed with Ki-67 antigen. The immunoexpression of p53 protein was found to be weak, with no remarkable behavior in any specific "diagnostic class". The differences in cell proliferation markers found herein further emphasize the progressive loss of epithelial layer organization in the course of the development of preneoplastic changes in cervical squamous epithelium. Furthermore, difficulties in morphologically distinguishing "borderline lesions" persist when cell cycle markers are studied, further supporting the suggestion to consider the lesions of CCHPV and CIN I together as only one diagnostic class. Conversely, the different immune profile found between CIN II and III further supports the validity of the subdivision of CIN into three groups.
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PMID:Relevance of the rates of PCNA, Ki-67 and p53 expression according to the epithelial compartment in cervical lesions. 1143 11

The present investigation evaluated the relationship between dysplasia of the uterine cervix and telomerase activity, expression of p53, MIB-1 and PCNA. Telomerase activity was measured on cervical cytobrush material from 126 women suspected of having dysplasia and 61 controls using the telomeric repeat amplification protocol. Immunohistochemistry was used to detect the tumor suppressor protein p53 and cell proliferation, the latter by MIB-1 and PCNA expression. Infection with human papillomavirus 16 was detected by PCR amplification and Southern blot hybridization of DNA extracted from the same brush material. Positive telomerase activity was found in 5 of 43 (11.6%) normal samples, 12 of 57 (21.1%) samples with inflammation or koilocytosis, 7 of 17 (41.2%) CIN 1 (cervical intraepithelial neoplasia, grade 1), 8 of 20 (40.0%) CIN 2, and 25 of 42 (59.5%) CIN 3/ CIS. Telomerase activity was significantly related to the level of dysplasia (p<0.001) and proliferation measured by MIB-1 (p=0.019), but not to the level of PCNA (p=0.445), HPV 16 status (p=0.098) or staining for p53 (p=0.271). Dysplasia was also related to PCNA, MIB1, p53, and presence of HPV 16. A sequential increase in the examined parameters, paralleling the progression of abnormality, was observed. PCNA and telomerase showed an increase in CIN 1, MIB-1 and HPV16 in CIN 2, and finally p53 in CIN 3/CIS.
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PMID:Telomerase activity, MIB-1, PCNA, HPV 16 and p53 as diagnostic markers for cervical intraepithelial neoplasia. 1187 14

An immunohistochemical study was carried out with monoclonal antibodies to estrogen receptors (Ers), Ki-67, BCL-2, P53 and human papillomaviruses (HPV) of normal cervix (7 cases), cervical leukoplakia (5 cases), CIN I (7 cases) and CIN II-III (6 cases). Correlations were also investigated between hyperestrogenemia and molecular changes in the exocervix. About two thirds of patients with leukoplakia and precancerous changes had clinical signs of hyperestrogenemia which led to proliferation of estrogen-sensitive parabasal cells. Due to neoplastic epithelial transformation the number of cells with Ki-67, P53 and HPV positive reactions in the nuclei increased, while Ers and BCL-2 expression decreased. Because active proliferative parabasal cells are needed for HPV replication we consider hyperestrogenemia as a factor stimulating development of neoplastic changes in the uterine cervix.
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PMID:[Immunohistochemical examinations of dyskeratosis and exocervical neoplasia in gynecological pathology]. 1253 23


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