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)

Wet autoclaving is a simple, reliable and time-effective method for antigen retrieval in routinely processed archival material. Both routine diagnostic (e.g., oestrogen and progesterone receptors, cytoskeletal proteins) and research antibodies (e.g. various p53 antibodies, mdm-2, bcl-2, MIB-1) are reported to demonstrate its application. We autoclaving may allow successful application of antibodies in paraffin-embedded tissues designed for use on frozen sections. The technique has the potential to reliably handle up to 200 sections at a time, without evidence of any significant damage to the sections or nuclear morphology.
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PMID:[Moist autoclaving. A simplified method for antigen unmasking]. 785 3

We analyzed the p53 expression immunohistochemically in 50 specimens of hepatocellular carcinoma (HCC) using two monoclonal antibodies (DO7 and PAb1801) and one polyclonal antibody (CM1), which recognize both wild and mutant type p53 proteins and can be used for paraffin-embedded sections. Fifteen of the 50 HCC specimens (30%) showed p53 expression localized at tumor nuclei, and this expression was significantly more frequent in HCCs with histologically lower differentiation. Except for serum titers of alpha-fetoprotein, the p53 expression had no statistically significant correlation with clinicopathological parameters, including hepatitis virus infection, tumor size, and background liver diseases. Conversely, the cell proliferative activities of tumor cells as assessed by mitotic index and immunostaining for MIB-1 were well correlated with the grade of histological differentiation. Moreover, MIB-1 immunostaining was shown to be useful in distinguishing well differentiated HCC from hepatocytes in chronic liver diseases. It also was shown that p53 expression was strongly associated with cell proliferative activity. Our results indicate that p53 expression takes place in the late stage of tumor progression and is related to the high malignant potential of HCCs.
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PMID:Immunohistochemical detection of aberrant p53 expression in hepatocellular carcinoma: correlation with cell proliferative activity indices, including mitotic index and MIB-1 immunostaining. 789 Feb 86

The monoclonal Ki-67-specific MIB-1 and p53 protein-specific DO-1 antibodies were used to identify proliferating cell fractions on microwave-pretreated paraffin sections of 7 cutaneous Bowen's disease specimens. A high Ki-67 score was characteristic of all cases examined, and significant p53-positivity was seen in 4 cases. In the peritumoral, histologically normal epidermis, Ki-67- and p53-positive cells were frequently present, in one case with very high scores (89% as well as 82%, respectively). These findings indicate an increase in the proliferative activity of the Bowen cells (high Ki-67 score) and that p53 mutations are frequently found in this disease. The p53 expression was not related to the Ki-67 score. The expression of Ki-67 and p53 in morphologically normal epidermal cells is also discussed. The histologically normal epidermal cells expressing p53 and Ki-67 antigens may correspond to pre-malignant clones.
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PMID:Ki-67 and p53 expression in cutaneous Bowen's disease: an immunohistochemical study of fixed-embedded tissue sections. 791 36

The clinicopathological and immunocytochemical features of nine cases of salivary duct carcinoma are described. This relatively rare tumour, which only recently has been widely recognized as a separate entity, is highly malignant and caused the death in eight of the patients. The tumour cells are arranged in cribriform and solid growth patterns, where the solid tumour nests frequently have comedo necrosis, and a fibrous, often sclerotic, stroma is present. The infiltrating desmoplasmic component and the diffuse invasive growth into adjacent adipose parotid tissue have similarities to ductal breast carcinoma. Immunocytochemical investigation of salivary duct carcinoma showed constant overexpression of c-erbB-2 as detected by membrane accentuation, and high proliferative activity as detected by nuclear positivity for MIB 1 (Ki-67). Changes in the expression of p53 and retinoblastoma gene product do not constitute a constant event in salivary duct carcinoma. A few of the tumours showed scattered cells with distinct nuclear positivity for both progesterone and oestrogen receptors. We emphasize that this highly malignant salivary gland tumour has a characteristic morphology, may not be as rare as previously considered, and that prompt and aggressive therapy is needed.
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PMID:Salivary duct carcinoma--a highly aggressive salivary gland tumour with overexpression of c-erbB-2. 793 25

Microwave oven (mwo) is used to stimulate tissue fixation and to retrieve antigens damaged by fixation. Heavy metal salt solutions, water, and citric acid buffer (cab) have been suggested for this purpose. A serie of tumors treated with cab and phosphate-buffered saline (pbs) with mwo were studied immunohistochemically with 24 antibodies. Controls were treated in the same way, except for microwaving. The antibodies were directed against antigens of the following tumors: breast and prostate carcinoma, carcinoid, lymphoma and melanoma. The results showed that cab enhanced the immunoreactivity of the following antigens: estrogen receptors (AMAC), progesterone receptors (Novocastra), HMB45, vimentin, leukocyte common antigen, PCNA, p53, MIB-1 (Ki-67) and prostatic specific antigen. The antigens that did not improve their immunoreactivity, when compared with the control series were: factor VIII, keratin, Leu 22, L26, neuron-specific enolase, CEA, chromogranin, HBME-1, smooth muscle actin and EMA. Microwaving equally improved protein S100 and desmin either with cab or pbs. The only antigen that improved with pbs was actin. The results with B72.3 and NKI/C3 were poor and not reliable. In conclusion microwaving with cab enhances the immunoreactivity of the antibodies mentioned above leading to an increase in sensibility without loosing specificity.
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PMID:[Antigen retrieval by microwave oven with buffer of citric acid]. 799 28

Thirty cases of hemispheric astrocytic tumors of childhood, consisting of 11 pilocytic astrocytomas, 2 fibrillary astrocytomas, 9 anaplastic astrocytomas, and 8 glioblastomas, were studied for the presence of p53 mutations and for immunohistochemical demonstrations of p53 and proliferation markers PCNA and Ki-67 MIB-1. The study was performed using polymerase chain reaction (PCR)-assisted single-strand conformation polymorphism analysis of exons 5-8 and direct sequence analysis of PCR products. For immunohistochemistry, DO1 and PAb 1801 were used. No mutation and no positivity for p53 protein were found in pilocytic astrocytomas. Mutations (at codons 144, 202, and 245) were found in 2 out of 8 glioblastomas and in 1 out of 9 anaplastic astrocytomas, whereas positive staining was found in 11 out of 17 malignant gliomas. Cases with mutations showed the highest p53 labeling index and also PCNA and MIB-1 labeling indices. The negative results in pilocytic astrocytomas are in line with the benign course of these tumors, whereas for malignant gliomas no difference seems to exist in comparison with adult cases.
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PMID:Mutations and immunohistochemistry of p53 and proliferation markers in astrocytic tumors of childhood. 852 18

Dysplasia in squamous metaplasia of the respiratory tract was believed to be a reversible premalignant lesion. Recently, presumably irreversible genetic alterations have been demonstrated in squamous metaplasia with dysplasia in lung-resection specimens. The genetic alterations were closely similar to those in adjacent bronchial carcinoma. There remains the question of which changes in squamous metaplastic lesions are premalignant, and which of these changes predict the occurrence of carcinoma of the respiratory tract. The purpose of this study was to determine the positive predictive value for respiratory-tract malignancy of the grade of dysplasia, p53 immunoreactivity, proliferative activity, and Bcl-2 in bronchial biopsy specimens exhibiting squamous metaplasia. Bronchial biopsies of 51 patients with squamous metaplasia diagnosed between 1982 and 1993 were used. Immunohistochemistry was done after microwave pretreatment of the biopsy specimens. Only unequivocally stained nuclei were counted. Normal bronchial epithelium obtained from autopsies was used as a control. In 31 patients, a synchronous or metachronous carcinoma was present (61%). Positive p53 immunoreactivity was found in 22 of the 51 patients (43%). The positive predictive values of p53 and of a high grade of dysplasia for carcinoma of the respiratory tract were 91% and 80%, respectively. Although the hyperproliferative state of squamous metaplastic lesions was clearly established, neither the percentage of MIB-1 labelling nor the mitotic index distinguished patient groups with and without carcinoma. No increased Bcl-2 immunostaining was found in squamous metaplasia. In conclusion, p53 immunoreactivity in squamous metaplastic lesions in bronchial biopsies is a marker of carcinoma of the respiratory tract.
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PMID:P53 in squamous metaplasia: a marker for risk of respiratory tract carcinoma. 854 51

The expression of both epidermal growth factor (EGF) and platelet-derived growth factor (PDGF), and of their receptors (EGFR and PDGFR) was immunohistochemically examined in 37 cases of osteosarcoma. Furthermore, immunostaining for p53 protein and Ki-67 antigen by MIB-1 was carried out and compared with the above results. EGFR (81%) expressed more often than EGF (51%) and the expression of EGF and EGFR, and PDGF and PDGFR were recognized in 49% and 38%, respectively. In eleven cases (30%), the expression of both growth factors and their receptors was combined. Anaplastic osteosarcoma showed higher MIB-1 index than osteoblastic and fibroblastic subtypes (P < 0.05). High grade osteosarcomas (G3 and G4) revealed higher MIB-1 index compared with low grade tumors (G1 and G2). PDGF positive tumors (MIB-1 index: 20.0) showed significantly higher proliferation compared with PDGF negative tumors (MIB-1 index: 6.5) (P < 0.01). Five out of 37 cases (13.5%) showed positive immunoreaction for p53. There was no correlation of p53 status with MIB-1 index and the expression of growth factors or their receptors. Our results suggest that PDGF expression may be an important mediator of cell proliferation control, via an autocrine mechanism, in human osteosarcoma.
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PMID:Expression of growth factors and their receptors in human osteosarcomas. Immunohistochemical detection of epidermal growth factor, platelet-derived growth factor and their receptors: its correlation with proliferating activities and p53 expression. 854

Direct evidence of tumour seeding in distant organs at the time of surgery for gastric cancer is not available. An immunocytochemical assay for epithelial cytokeratin protein may fill this gap since it is a feature of epithelial cells that would not normally be present in bone marrow. The bone marrow of 46 patients with primary gastric cancer was examined for tumour cells, using immunocytochemical techniques and antibody reacting with cytokeratin, a component of the intracytoplasmic network of intermediate filaments. The monoclonal antibody CK2 recognises a single cytokeratin polypeptide (human cytokeratin no. 18) commonly present in epithelial cells. The expression of tumour-suppressor genes p53 and RB for the primary lesion was also determined using the monoclonal antibodies PAb 1801 and 3H9 respectively, and the proliferating activity was determined by the Ki-67 antigen labelling index for MIB-1 antibody staining. Of these 46 patients, 15 (32.6%) presented with cytokeratin-positive cells at the time of primary surgery. The positive findings were related to the undifferentiated tissue type and to the prominent depth of invasion, but not to other clinicopathological factors. In 2 of 15 (13.3%) patients, the depth of invasion was limited to the mucosa. The metastatic potential to bone marrow did not relate to expressions of p53 and RB genes, or to the proliferating activity of MIB-1 staining for the primary lesion of gastric cancer. As tumour cells in bone marrow are indicative of the general disseminative capability of an individual tumour, this technique may be useful for identifying patients at high risk of metastasis from a gastric tumour.
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PMID:Cytokeratin-positive cells in bone marrow for identifying distant micrometastasis of gastric cancer. 855 89

A case is presented of pulmonary blastoma occurring in the right upper lobe of a 25-year-old man without distinct clinical features and laboratory abnormality. Light microscopic analysis revealed that the tumor was composed of branching glands and morulae embedded in a primitive but bland mesenchyme. Immunohistochemically the epithelial cells were immunoreactive for cytokeratins, S-100 protein, protein gene product 9.5, chromogranin A, calcitonin, and Ki-67 (MIB-1); the mesenchymal cells were immunoreactive for vimentin, actin, cytokeratins, and Ki-67; and all the tumor cells were negative for p53, estrogen receptor protein, and human chorionic gonadotropin beta. Characteristically, many epithelial cells contained optically clear nuclei which were immunoreactive for biotin (M743). Electron microscopic analysis revealed that the optically clearing change was due to replacement of the central area of the nuclei by a mass of parallel-arranged 7- to 10-nm filaments, and biotin-immunoreactive products were mainly localized in the nuclear matrix. Additionally, spherical bodies were identified in the cytoplasm of the nuclear filament-aggregated cells, suggestive of an intimate pathogenetic association of the two morphological abnormalities. The similarity of the aggregated nuclear filaments to those observed in gestational endometrium and ovarian endometrioid carcinoma implies that a similar mechanism plays a role in the pathogenesis of these abnormalities.
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PMID:Pulmonary blastoma: an ultrastructural and immunohistochemical study with special reference to nuclear filament aggregation. 859 6


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