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)

We examined 59 breast cancers for p53 and bcl-2 protein expression by immunohistochemistry. The results were correlated with Ki-67 immunostaining. p53-negativity was noted in 40 cases and the remaining 19 tumours were p53-positive. Thirty-six tumours showed strong expression of bcl-2 and in 23 no staining for this protein was observed. We found statistically significant reverse correlation between expression of p53 and bcl-2 in majority of carcinomas: 31 cases were bcl-2 positive and p53-negative, and 14 tumours were bcl-2-negative and p53-positive. Six carcinomas showed no nuclear staining for Ki-67 and in the remaining 53 the percent of cancer cells positive for Ki-67 ranged from 1 to 60 (mean: 14.6). In these 53 cases we found that bcl-2-positive tumours were characterized by lower proliferation than bcl-2-negative tumours, the mean value of Ki-67 immunostaining being 10.7% and 23.0%, respectively. p53-negative tumours showed lower proliferation than p53-positive tumours: mean Ki-67 index was 10.2% and 23.9%, respectively. We conclude that immunohistochemically detected p53 and bcl-2 proteins show a significant inverse relationship in majority of breast carcinomas and their expression correlates with tumour proliferation (Ki-67 immunostaining).
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PMID:Immunohistochemical analysis of bcl-2 and p53 expression in breast carcinomas: their correlation with Ki-67 growth fraction. 777 1

The biologic behavior of invasive pituitary adenomas is poorly understood and appears to be intermediate between intrasellar adenomas and pituitary carcinoma. Utilizing immunohistochemistry on tissue sections, we examined 10 invasive pituitary adenomas involving the sphenoid sinus with a panel of cellular and molecular markers and compared the results with 10 noninvasive pituitary adenomas and five normal pituitary glands. The panel included Ki-67 and PCNA (proliferation cell nuclear antigen), cell proliferation indicators; interleukin 6 (IL-6), a multifunctional cytokine; heat shock protein 27 (HSP 27), a stress response protein; and p53, a tumor suppressor gene product. We found strong expression of IL-6 in normal pituitary glands, 20% of noninvasive and 50% of invasive adenomas. HSP 27 was absent in normal glands and present in 10% of noninvasive and 50% of invasive adenomas. The Ki-67 and PCNA proliferation index was above normal but was essentially the same in the two groups. p53 was not detected in any specimens. We propose that both IL-6 and HSP 27 may be markers of biologic aggression in pituitary adenomas.
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PMID:Biologic markers of invasive pituitary adenomas involving the sphenoid sinus. 777 77

Major differences in the long-term clinical response to castration therapy of prostatic carcinoma suggests intertumoral differences in cellular response and defines a need for identification of patients with an eventually positive outcome as well as those in need of additional treatment. Using morphometry, monoclonal antibodies against Bcl-2, c-myc, Ki-67, and p53 proteins, and an in situ method to visualize apoptotic cells, we examined the short-term response of prostatic tumors to castration in core biopsies from 18 prostatic cancer patients taken the day before and 7 days after castration. At the histological level, 3 tumors seemed practically unaffected by castration. In 15 tumors, castration induced vacuolization of tumor cell cytoplasm and decreases in nuclear area and Ki-67 index. In these 15 tumors, apoptotic index was significantly increased in 6, principally unaffected in 6, and decreased in 3. The 6 tumors responding with an increase in apoptotic index were WHO grade 1 or 2 and negative for p53, c-myc, and Bcl-2 or contained only few Bcl-2- or c-myc-positive tumor cells before therapy. The 12 tumors in which apoptotic index was unaffected or decreased were WHO grade 2 or 3 and immunopositive for one or more of p53, Bcl-2, and c-myc proteins before therapy. The Bcl-2 index was significantly increased in 10 patients. Prostatic tumors may respond in a variety of possibly predictable ways to castration therapy including a decrease in apoptotic index. The magnitude of these responses are not correlated in individual tumors, suggesting that the common classification of prostatic tumors as either androgen dependent (dying after castration) or independent (not responding at all to castration) may be an oversimplification.
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PMID:Castration therapy rapidly induces apoptosis in a minority and decreases cell proliferation in a majority of human prostatic tumors. 777 76

Immunocytochemical methods were examined for their sensitivity in the detection of nuclear antigens (proliferating cell nuclear antigen, Ki-67 associated proliferative antigen and p53 protein) in the leukemic cells. A comparative study of the biotin streptavidin enhanced peroxidase technique, the biotin streptavidin enhanced alkaline phosphatase technique and the indirect immunoperoxidase technique showed that the indirect immunoperoxidase technique was more sensitive than the other techniques for detecting p53 protein. The results of several fixation methods demonstrated that formalin and methanol, formalin and ethanol (1:9) and buffered formalin acetone gave good results for detecting p53 protein. In the eosinophils and neutrophils the endogenous peroxidase reaction disappeared after microwave heating for over three minutes. Thus enzyme pre-blocking of blood smears could be omitted. Four solutions for microwave treatment were tested. Excellent antigen retrieval was obtained with pH6.4, pH7.4 phosphate buffer saline and pH6.0 citric acid. However, the nuclear antigens could not be retrieved and the positive reaction could not be obtained after the treatment with distilled water. The optimal microwave heating time was five to ten minutes. The indirect immunoperoxidase technique performed using microwave treatment under these optimal conditions may be potentially applicable for detecting low levels of nuclear antigens in the leukemic cells within conventional blood smears.
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PMID:[Detection of nuclear antigen within the leukemic cells using immunocytochemical technique]. 778 70

An immunohistochemical analysis with monoclonal antibodies against Ki-67 (MIB 1), PCNA (PC10), p53 and Lewis X antigen was performed on 47 squamous carcinomas of the larynx after partial laser resection. Ki-67 index and expression of Lewis X antigen correlated significantly with both tumor recurrence rate and tumor-free interval. A much weaker relationship was found for the expression of proliferating cell nuclear antigen (PCNA), and no correlation existed with p53 expression. In conclusion, examination of Ki-67 and Lewis X antigen is thought to provide useful prognostic information concerning laser-resectable squamous carcinomas of the larynx.
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PMID:[Value of monoclonal antibodies (PC 10, MIB1, p53 and LeuM 1) for assessing the prognosis of patients with squamous epithelial carcinoma of the larynx after partial laser resection]. 779 71

The bcl-2 protooncogene was initially discovered at the t(14;18) chromosomal breakpoint in follicular lymphomas. It has been demonstrated that bcl-2 protein (Bcl-2) expression blocks apoptosis and plays an important role in cell development and maturation. In the present study, Bcl-2 expression was immunohistochemically examined in 103 cases of gastric carcinoma, as well as 64 cases of non-carcinous gastric mucosa, and its correlation with apoptosis, cell proliferation and p53 immunoreactivity was investigated. Bcl-2 was detected in 18.0% of differentiated-type gastric carcinomas (9 of 50) and 7.5% of the undifferentiated type (4 of 53). In adjacent intestinal metaplastic gastric epithelium, the incidence of Bcl-2 positivity in the incomplete type (21/23, 91.3%) was significantly higher than in the complete type (23/41, 56.1%) (P < 0.04). Double immunostaining for Bcl-2 and Ki-67 clearly revealed the majority of Bcl-2-positive cancer cells to be in a nonproliferating state, although some cancer cells expressed both proteins together. Statistical assessment demonstrated that the average Ki-67 labeling index and apoptotic labeling index in Bcl-2-positive foci were significantly lower than in Bcl-2-negative foci (P < 0.0001, P < 0.0003). In addition, a significant dissociation between Bcl-2 and p53 immunoreactivity was found in cancer tissues. These results indicate that aberrant Bcl-2 expression in gastric carcinomas possibly originates from intestinal metaplastic epithelium, and suggest a possible role in tumor development and growth.
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PMID:Bcl-2 expression and its association with cell kinetics in human gastric carcinomas and intestinal metaplasia. 779 1

Aberrant p53 immunoreactivity has been found in skin pre-malignancies and dysplasias such as Bowen's disease and actinic keratoses. Vulval lichen sclerosus (LS) has been reported to be pre-malignant, with an association of vulval carcinoma in 3% to 6% of patients. In contrast, non-genital LS appears to have no malignant potential. In this immunocytochemical study, we investigated p53 expression in 10 cases of histologically proven vulval LS and 9 cases of non-genital LS using the murine monoclonal antibody Do-1 raised against recombinant human p53 which reacts with both wild-type and mutant p53. None of the vulval specimens had epithelial dysplasia or malignancy. Normal vulval (7 cases) and non-genital skin (5 cases) were used as tissue controls, respectively. The cell proliferation index was also studied using the MIB 1 monoclonal antibody which detects the cell-cycle associated Ki-67 antigen. The technique of microwave irradiation for antigen unmasking was employed on formalin-fixed and paraffin-embedded tissues. There was a significant increase in p53 immunoreactivity in vulval LS (32.13 +/- 15.11 epidermal cells per 100 basal cells) compared to normal vulval skin (7.52 +/- 5.04 epidermal cells per 100 basal cells) (p < 0.001), whereas the MIB 1 labelling index was lower in vulval LS (39.45 +/- 15.88 epidermal cells per 100 basal cells) than in normal controls (86.26 +/- 32.31 epidermal cells per 100 basal cells) (0.001 < p < 0.01). In contrast, there was no significant difference in p53 immunoreactivity or MIB 1 labelling index between non-genital LS and normal controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Altered p53 expression and epidermal cell proliferation is seen in vulval lichen sclerosus. 779 88

Sixty-six unselected breast cancers were analyzed in cytologic smears and histologic sections for the expression of Ki-67, proliferating cell nuclear antigen (PCNA), estrogen receptor protein (ERP), and p53 protein using a standard immunochemical method. The results, expressed as both positive cases and labelling index (LI), were compared with clinical and pathobiological variables. Ki-67 and PCNA immunostaining was seen in all cases, whereas ERP was detectable in 46/63 cases and p53 protein in 20/66 cases. The expression of these markers was generally lower in cytology than in histology, though the differences were not statistically significant. PCNA-LI and Ki-67-LI were closely correlated (P < 0.001), the mean PCNA:Ki-67 ratio being 0.92 +/- 0.57. Occasional discrepancies, however, were found. PCNA and Ki-67 expression was associated with an increase in histologic grade and a decrease in ERP content of tumors, whereas p53 was statistically associated with no clinical or pathobiological variables. The data suggest that proliferative activity and oncogene overexpression may be reliably evaluated in breast cancer by FNA cytology, though PCNA is not a suitable indicator for cell proliferation. The results do not resolve the issue as to whether immunostaining for p53 protein constitutes a dedifferentiation product of the tumor, or is a fundamental aspect of the malignant progression. Survival studies in a larger series of tumors are thus needed to elucidate this point.
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PMID:Expression of proliferating cell nuclear antigen, Ki-67 antigen, estrogen receptor protein, and tumor suppressor p53 gene in cytologic samples of breast cancer: an immunochemical study with clinical, pathobiological, and histologic correlations. 781 60

Fifty cancers, seven borderline tumors, and two adenomas of the ovary were immunohistochemically examined for alteration of p53 to clarify its clinical significance. Nuclear accumulation of p53 protein was detected in 60% of the cancers, but in none of the borderline tumors or adenomas. No significant correlation was found between aberrant expression of p53 and clinical stage or histological type. DNA aneuploidy was significantly more common and the Ki-67 index was significantly higher in the cancers with altered p53 protein than in those without it. There was a concordant expression level of p53 in primary and matched metastatic lesions in all twelve pairs of cancers examined. These findings suggest that alteration of p53 protein is an event that occurs in the development of cancer, but not of borderline tumors of the ovary, and that it occurs before metastasis and remains unchanged thereafter.
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PMID:Alteration of p53 in ovarian cancer: its occurrence and maintenance in tumor progression. 781 92

The pathological and biological features of a consecutive series of impalpable invasive breast carcinoma, detected by mammography in the prevalent round of the breast screening programme, have been compared with a clinically presenting group of carcinomas in age-matched patients. There was a significantly higher prevalence of tubular carcinomas as well-differentiated infiltrating ductal carcinomas in the mammographically detected group, and a lower prevalence of poorly differentiated infiltrating ductal carcinomas. Lymph node metastasis was found in 6.5% of the impalpable group compared with 53% of the clinical group. The prevalence of oestrogen receptor was much higher in the impalpable group (96%) than in the control group (67%), although there were no significant differences for progesterone receptor. The prevalence of pS2 was also much higher in the impalpable group, as was cathepsin D. This finding is surprising in view of the reported relationship between cathepsin D and poorer survival. p53 and c-erb-2 proteins were detectable in fewer impalpable carcinomas. The mean MIBI (Ki-67) index was lower in the impalpable group (11.6) than in the clinical group (15.25). Within the mammographically detected group there was a significant difference in the MIBI index between tubular carcinomas and the different grades of infiltrating ductal carcinomas, with a wide range in each category but no association with size. The impalpable carcinomas detected by mammography differ from clinically presenting carcinomas in many ways, raising the question of whether a proportion or all would progress (dedifferentiate) with time.
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PMID:Pathological and biological features of mammographically detected invasive breast carcinomas. 759 62


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