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)

Ki-67 and P53 expression were studied using immunohistochemistry on tissue samples obtained during transurethral electroresection or needle biopsy in 62 patients with prostatic lesions: group 1 (n = 15)--benign prostatic hyperplasia (BPH), group 2 (n = 10)--high-grade prostatic intraepithelial neoplasia (PIN 3), group 3 (n = 10)--low-grade prostatic carcinoma (PC, Gleason score 2-4), group 4 (n = 12) intermediate-grade prostatic carcinoma (PC, Gleason score 5-7) and group 5 (n = 15) high-grade prostatic carcinoma (PC, Gleason score 8-10). Moreover, in the groups examined the associations between expression of Ki-67 and P53 were analysed. Paraffin-embedded tissue samples were immunostained with monoclonal antibody anti-P53 and polyclonal antibody anti-Ki-67 using avidinbiotin-peroxidase method. Our study revealed lack of Ki-67 and P53 immunoreactivity in BPH. Only 3 out of 10 high-grade PIN exhibited Ki-67 positivity, but there was no immunopositivity of P53 protein in this group. Although immunopositivity of Ki-67 increased with the histological grade of prostatic cancer, the differences in Ki-67 expression between intermediate and high-grade cancer did not reach statistical significance. A similar level of Ki-67 reactivity in intermediately-differentiated and poorly-differentiated prostate cancer suggests a similar biology of these cancers. P53 protein positivity was noted in 62.2% cases of prostate cancer. Moreover, the highest level of P53 accumulation in intermediate-grade carcinomas may predict the aggressive progression and risk of metastases in these cases. No significant differences in P53 immunopositivity between low-grade and high-grade PC were noted. Interestingly, only in low-grade PC there was a significant positive correlation between expression of Ki-67 and P53 protein.
Pol J Pathol 2000
PMID:Ki-67 antigen and P53 protein expression in benign and malignant prostatic lesions. Immunohistochemical quantitative study. 1083 1

The p53 protein expression in the invasive squamous cell carcinoma of the cervix was evaluated immunohistochemically. Its predictive role in the correlation with histological grading and staging was analyzed. 13.7% of examined cases (10/73) presented positive protein expression. There was no correlation between the intensified protein p53 expression and particular prognostic histological factors.
Ginekol Pol 1999 Jul
PMID:[Immunohistochemically expression of the protein p53 evaluated in invasive squamous cell carcinoma of the cervix]. 1089 92

The tumor suppressor protein p53 is frequently inactivated in tumors. It functions as a transcriptional activator as well as a repressor for a number of viral and cellular promoters transcribed by RNA polymerase II (Pol II) and by RNA Pol III. Moreover, it appears that p53 also suppresses RNA Pol I transcription. In this study, we examined the molecular mechanism of Pol I transcriptional inhibition by p53. We show that wild-type, but not mutant, p53 can repress Pol I transcription from a human rRNA gene promoter in cotransfection assays. Furthermore, we show that recombinant p53 inhibits rRNA transcription in a cell-free transcription system. In agreement with these results, p53-null epithelial cells display an increased Pol I transcriptional activity compared to that of epithelial cells that express p53. However, both cell lines display comparable Pol I factor protein levels. Our biochemical analysis shows that p53 prevents the interaction between SL1 and UBF. Protein-protein interaction assays indicate that p53 binds to SL1, and this interaction is mostly mediated by direct contacts with TATA-binding protein and TAF(I)110. Moreover, template commitment assays show that while the formation of a UBF-SL1 complex can partially relieve the inhibition of transcription, only the assembly of a UBF-SL1-Pol I initiation complex on the rDNA promoter confers substantial protection against p53 inhibition. In summary, our results suggest that p53 represses RNA Pol I transcription by directly interfering with the assembly of a productive transcriptional machinery on the rRNA promoter.
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PMID:Repression of RNA polymerase I transcription by the tumor suppressor p53. 1091 76

The authors estimated PCNA and P53 in subjects with laryngeal cancer in whom local or nodal recurrences were observed. The study included 54 patients from Upper Silesia in age 37-79 years (mean 57 +/- 8.8). The mean value of the PCNA index in subjects with local recurrence (LR) was 24.2% +/- 12.1 while in subjects without LR 22.1% +/- 9.4 (p > 0.05). Additionally, 21 subjects were separated from the investigated group in whom no lymph node metastases were found during laryngectomy. Among these subjects in 16 LR was observed (PCNA index was 30.9% +/- 12.5) while in remaining 5 subjects, in whom LR did not develop, PCNA index was 21.7% +/- 11.2. Analysis of the P53 index in subjects with LR revealed significantly higher values (19.2% +/- 9.1) in comparison to cases without LR (13.2% +/- 6.3). Our study revealed usefulness of the P53 and PCNA as markers which could support the histological diagnostic process describing biology of the cancer cells. The demonstrated increase of PCNA and P53 index in patients with LR might be useful in prediction of LR.
Otolaryngol Pol 2000
PMID:[Assessment of usefulness of PCNA and protein p53 in subjects with laryngeal cancer with local recurrence]. 1097 77

The aim of the study was analysis of relationship between proliferation index (PCNA) and protein p53 content in dysplastic laryngeal epithelium and the degree of dysplasia, age of patients and smoking. The study population consisted of 45 patients (mean age 57.7 +/- 6.2) with chronic laryngitis. It was revealed epithelial dysplasia varying in intensity in 36 patients and epithelial hyperplasia without dysplasia (acanthosis) in 9 patients--control group. Mean value of p53 protein index was 8.91 +/- 7.43% in dysplastic epithelium and 3.67 +/- 3.4 in hyperplastic epithelium without dysplasia. The difference was statistically significant (p = 0.007). P53 content significantly differed between groups with grade I and grade II dysplasia (p = 0.03) and between groups with grade I and grade III dysplasia (p = 0.03). The difference was found between groups with grade II and III dysplasia and group with hyperplasia without dysplasia. The analysis of the correlation between degree of dysplasia and value of PCNA index showed absence of differences. There was no relationship between smoking, age of patients and Value of p53 and PCNA index.
Otolaryngol Pol 2000
PMID:[Precancerous states of the larynx: analysis of mono- and polyclonality of the cells with high proliferative index (p53, PCNA)]. 1097 78

Cyclin D1, P53 and P21 (WAF1) are cell cycle regulating proteins, playing a crucial role in oncogenesis of a large number of human malignancies, and loss of activity of P53 and P21 (WAF1) proteins seems to be one of the most important regulatory mechanisms of carcinogenesis in colorectal cancer. To find out their mutual relations we investigated the expression of cyclin D1, P53 and P21 (WAF1) in 122 colorectal cancers by immunohistochemistry. Positivity for cyclin D1 was found in all the cases (100%), positivity for P53 in 96 cases (70%) and positivity for P21 in 48 cases (39%). Statistical analysis revealed a statistically significant inverse correlation between P53 and P21 (WAF1)-immunopositivity and also between P21 (WAF1)-immunopositivity and the degree of cyclin D1-immunopositivity. These data suggest that in colorectal cancer induction of P21 (WAF1) may occur mostly in a P53-dependent pathway. Wild-type P53, which is undetectable by immunohistochemistry, induces transcriptionally P21 (WAF1) and in tumours it may cause its accumulation, while mutations of the P53 may result in a sufficient increase of intracellular protein having no ability to transactivate P21 (WAF1). Moreover P21 (WAF1) as the main cyclin-dependent kinases (CDKs) inhibitor may also inhibit the activity of the cyclins, thus overexpression of P21 (WAF1) may result in reduced level of cyclin D1.
Pol J Pathol 2000
PMID:Comparative evaluation of the expression of cell cycle regulating proteins: cyclin D1, P53 and P21 (WAF1) in colorectal cancer. 1097 28

The purpose of the study was to assess the expression of p53 in non-small cell lung cancer (NSCLC) before and after treatment with cisplatin and vepeside (PE) and to define a relationship between p53 expression and responsiveness to chemotherapy prior to surgery. Material for study consisted of specimens obtained from neoplastic infiltrate before chemotherapy (biopsy material) and tumour specimens obtained after chemotherapy (surgical material). The study population was a group of 35 patients with stage IIIA NSCLC. p53 protein accumulation was detected by immunohistochemistry using antibodies against p53: NCL-p53 (clone BP-53-12) (Novocastra) on paraffin embedded specimens. p53 expression was found in 21 patients (60%) before and after chemotherapy. In 14 patients (40%) p53 negativity was seen both in biopsy and surgical material. The level of p53 staining after chemotherapy as compared with that before treatment changed from -53 to +34. There was a mean increase by 1.52, which appeared statistically accidental (p > 0.70). There was no significant relationship between p53 expression and responsiveness to chemotherapy (from p > 0.33 to p > 0.70) and between the magnitude of changes in p53 expression and response to chemotherapy (p > 0.39). There was also a very low correlation (r to 0.10; p > 0.50) between responsiveness to therapy and p53 negativity.
Pol J Pathol 2000
PMID:Immunohistochemical study of p53 in non-small cell lung cancer before and after preoperative chemotherapy. 1097 29

In the study the expression of Ki-67, p53, bcl-2 and apoptotic index in ten cases of lobular capillary hemangioma (LCH), ten of capillary hemangioma (CH), and five of epithelioid hemangioma (EH) was examined. The expression of Ki-67, p53 and bcl-2 did not differ significantly between each group of lesions. Instead, significant differences in apoptotic index between LCH and CH were found. The expression of bcl-2 was positively correlated with that of Ki-67 in LCH and CH group, but negatively correlated in the EH group. Our results confirm that LCH, EH and CH, which are histologically similar, are different in terms of proliferation/apoptosis balance. This reflects their different biology, and presumably pathogenesis.
Pol J Pathol 2000
PMID:Proliferation and apoptosis within the oral mucosa "hemangiomas". 1097 33

The authors estimated PCNA and P53 in subjects with laryngeal cancer with local or nodal recurrences. The study concerned 54 patients from Upper Silesia aged 37-79 (mean 57 +/- 8.8). The mean value of the PCNA index in subjects with local recurrence (LR) was 24.2% +/- 12.1 while in subjects without LR 22.1% +/- 9.4 (p > 0.05). Additionally, 21 subjects in whom no lymph node metastases were found during laryngectomy were separated from the investigated group. In 16 of them local recurrences were observed and the mean value of PCNA index was 30.9% +/- 12.5. In remaining 5 subjects in whom local recurrences were not developed the mean value of PCNA index was 21.7% +/- 11.2. The analysis of the P53 index in subjects with LR revealed significantly higher values (19.2% +/- 9.1) in comparison with cases without LR (13.2% +/- 6.3). The assessment of the mean values of PCNA and P53 index depending on T, N or stage as well as nodal recurrence did not reveal any statistical significance. Our study revealed usefulness of the P53 and PCNA as markers which could support the histological diagnostic process describing biology of the cancer cells. The demonstrated increase of PCNA and P53 index in patients with LR might be useful in prediction of LR.
Otolaryngol Pol 2000
PMID:[Assessment of usefulness of PCNA and oncoprotein p53 staining in prediction of the recurrences in subjects operated on for laryngeal carcinoma]. 1107 Jun 93

The aim of the study was to evaluate the prognostic relevance of p53 protein in non-small cell lung cancer. The 95 surgically treated patients were included (53 patients with squamous cell carcinoma, 29--with adenocarcinoma, 5--with large cell carcinoma, and 8--with mixed type). The protein was assessed immunohistochemically with the use of monoclonal antibodies DO7, DAKO. Positive staining was present in 44 patients. There was no survival difference between groups with and without protein (median survival--36 and 33 months, respectively; p = 0.86). In the multivariate analysis the only characteristics with prognostic impact in the entire group was stage of the disease. There was no correlation between the expression of p53 protein and disease-free survival. These results indicate that there is no prognostic relevance of p53 protein in non-small cell lung cancer.
Pneumonol Alergol Pol 2000
PMID:[Prognostic value of P53 protein in cells of non-small cell lung cancer]. 1120 Jul 47


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