Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.11.1.7 (peroxidase)
65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The expression of oncogene products related to cell growth (c-erbB-2, c-myc, ras p21, EGFR) was investigated in benign (15 cases) and malignant breast lesions (20 cases) by means of immunohistochemistry using the avidin-biotin-peroxidase technique with polyclonal and monoclonal antibodies. The aim of this study was to evaluate the relationship between the staining positivity and various morphological and biological features, such as tumour type, grading, hormone receptor status and cell kinetic parameters. In benign breast lesions, as expected, the kinetic parameters were low, both for Ki-67 and LI. All the specimens showed a diploid condition (the DI being equal to 1) and we found a limited degree of immunoreactivity for all the growth factors and oncogene products. In breast cancer we studied the distribution of immunohistochemical positivity for EGFR, c-erbB-2, c-myc, ras p21 and Ki-67, which was related to age, nodal status, ER and PgR receptor status, LI, DI and histopathological grading. A significant positive correlation was found both between ras p21 expression and nodal status and ER-ICA positivity. We observed a strong correlation between LI and Ki-67 and an inverse relation between Ki-67 and ER expression. These findings suggest the importance of studying the relationship between prognostic factors which may provide preoperative prediction in the biological behaviour of breast cancer, not only on biopsy specimens, but also on fine needle aspirates.
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PMID:Preliminary study on oncogene product immunohistochemistry (c-erbB-2, c-myc, ras p21, EGFR) in breast pathology. 134 7

A monoclonal antibody to proliferating cell nuclear antigen (PCNA/cyclin) has recently become available. This antibody, as opposed to Ki-67, can be used on formalin-fixed, paraffin embedded tissue sections and allows retrospective comparison of PCNA positivity to percent S + G2 + M of the cell cycle. To compare fresh lymphoma deoxyribonucleic acid (DNA) analysis with PCNA activity on fixed, paraffin-embedded sections, prospective flow cytometric studies of cell cycle analysis were performed on lymph nodes removed from 10 patients for diagnosis. Six patients had T-cell lymphoma, two had B-cell lymphoma, and two were benign. Using the peroxidase-antiperoxidase method, the nuclear positivity of archival lymphoma cases was also examined. To quantify PCNA positivity, a unique morphometric method was employed that utilized digital imaging by high definition television and ELAS (Earth Land Application Software), a geoscience software used extensively for color quantitation of remote sensed data. The immunologic percent PCNA positivity was 26.1 +/- 20 vs. percent S + G2 + M by flow cytometry of 22.4 +/- 10 with a correlation coefficient (r) of 0.55. This r-value compared favorably to data generated for Ki-67 in solid malignant neoplasms. The six more concordant cases had a percent PCNA positivity of 26.5 +/- 10.0 and a percent S + G2 + M of 27.3 +/- 8.6, r = 0.96. Our study is unique in that it compared fresh lymphoma DNA analysis data with paraffin PCNA data. It is our conclusion that immunologic PCNA positivity in paraffin sections correlates with fresh flow cytometric S + G2 + M in lymph nodes, although careful attention must be paid to the area of the node quantified for PCNA.
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PMID:The proliferative fraction in lymph nodes: a comparison of proliferating cell nuclear antigen morphometry to flow cytometry. 135 28

Total Ki-67 stained area percentage was studied in 32 B and 46 T malignant lymphomas (ML) using two different image analyser systems (TAS, Leitz; SAMBA TM 2005, TITN) respectively. The total Ki-67 area percentage was highly correlated to the number of Ki-67 positive cellular profiles (B-ML, r = 0.93; T-ML, r = 0.88), indicating that area percentage is a reliable alternative method to the manual cell counting. Image analysis allows quicker measurements, appropriate to large and strictly lymphomatous regions. The cell image processor (SAMBA TM 2005, TITN) linked to a color video camera was more suitable for immunohistochemical sections and allowed more automated and faster measurements than the texture analyser (TAS, Leitz) linked with a black and white camera. Alkaline phosphatase technique with fast red as chromogen was more suitable for the detection of Ki-67 stained area by thresholding than peroxidase technique with aminoethylcarbazol or with diaminobenzidine as chromogens. Significant differences were found between low and high grade in B and T ML according to the Kiel classification (mean values +/- SD of 7.7 +/- 3.8% and 16.6 +/- 6.2% in B-ML and of 10.2 +/- 7.9% and 25.6 +/- 16.3% in T-ML respectively). In follicular B-ML, considering follicular areas only, values were comparable to high grade ML; angioimmunoblastic-lymphadenopathy-like (AILD-type) T-ML belonging to low grade ML showed similar values to pleomorphic T-ML with medium and/or large cells belonging to high grade ML.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparative quantitative study of Ki-67 antibody staining in 78 B and T cell malignant lymphoma (ML) using two image analyser systems. 140 77

We examined the influence of different staining techniques [(three-step immunoperoxidase technique (IP); alkaline phosphatase-anti-alkaline phosphatase technique (APAAP)] on the quantitative evaluation of Ki-67-labeled nuclei. We studied five melanocytic skin tumors. From each case, five parallel sections were prepared and stained using the peroxidase-antiperoxidase (PAP) technique (slide 1) and the APAAP technique once (slide 2). Slide 3 consisted of a single repetition of the APAAP technique, slide 4 was a double repetition, and slide 5 was a third repetition. We assessed the volume fraction (VV) of Ki-67-positive nuclei using computer-assisted image analysis. For each staining group, the mean value and standard deviation of VV were calculated. Comparing VV values obtained from the different staining groups we did not find a statistically significant difference between the IP and the various APAAP steps (Wilcoxon test, p = less than 0.05). However, the staining procedure influenced the quantitative results to some extent. The mean VV of the five staining groups ranged in our study from 0.10 to 0.17%, which is narrow compared with the overall variability among different cases (dermal melanocytic nevus, 0.01%; metastatic malignant melanoma, 0.43%). Therefore, we can state that for a rough evaluation of Ki-67-positive nuclei, the influence of different staining methods is negligible; for a subtle quantitative analysis, however, it would nevertheless be preferable to always apply the same staining technique.
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PMID:The influence of staining procedures on the assessment of cell proliferation as defined by the monoclonal antibody Ki-67. 170 Aug 83

To compare the time course of in vitro expression of various proliferation-associated markers including Ki-67 antigen, transferrin receptors (TfR), and DNA polymerase alpha, six human tumour cell lines of different histological origin were studied under defined conditions. Proliferation markers were demonstrated by peroxidase/anti-peroxidase staining using specific monoclonal antibodies, and their expression was compared to results obtained from [3H]-thymidine incorporation assays and cell counting. Expression of all proliferation markers began to increase during the lag phase, and occurred earlier than elevations of [3H]dT incorporation and cell numbers were recorded. Maximum expression was observed before cell growth reached plateau phase. The time courses of expression of DNA polymerase and Ki-67 were almost identical. The closest correlation of [3H]dT incorporation with time course of expression of proliferation-associated markers was observed, when intranuclear staining of DNA polymerase was analysed. TfR were expressed earlier than the polymerase and Ki-67. Since TfR were also found at remarkable levels in resting cells, they seem less proliferation-specific than Ki-67 and DNA polymerase. While in rapidly growing cell lines more than 95% of the cells expressed Ki-67, TfR, and more than 75% DNA polymerase in cell nuclei, a malignant melanoma and a pleural mesothelioma line displayed fewer than 35% of cells stained for DNA polymerase in cell nuclei during log phase. Determination of growth fractions by monoclonal antibodies may thus contribute to the prediction of chemoresistance by identifying quiescent cells that are not sensitive to S-phase-specific drugs.
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PMID:Expression of the proliferation-associated Ki-67 antigen of transferrin receptors and of DNA polymerase alpha in human tumour lines: implications for in vitro chemoresistance. 173 31

The p53 gene is a tumor suppressor gene located on chromosome 17p. Deletions of this chromosome and point mutations of p53 have been implicated in the development of colonic neoplasms. We have analyzed the loss of heterozygosity of the human p53 tumor suppressor gene in 40 cases of colorectal carcinoma using two restriction fragment length polymorphisms detected by BglII and AccII restriction enzymes. p53 gene product expression was studied immunohistochemically in 64 colorectal carcinomas, 18 adenomas, and 40 normal colonic mucosae using an anti-human p53 monoclonal antibody (Pab 1801) and the avidin-biotin-peroxidase complex technique. Twelve of the 40 patients (30%) were polymorphic for the p53 gene. In ten of these informative patients (83%), the tumor samples showed the loss of one allele when compared with normal colorectal samples of the same patient. One of the homozygous patients showed a loss of both p53 alleles. p53 immunostaining was observed in 43 of 64 carcinomas (67%) but only in two adenomas (11%). These two positive adenomas showed areas of carcinoma in situ. The normal mucosa was always negative. No relation could be found between p53 immunostaining and the degree of differentiation, the extension of the tumor, or the Ki-67 proliferative index. Mucinous carcinomas and right-side carcinomas were less p53 immunoreactive (25% and 52%, respectively) than the usual adenocarcinomas (73%) and distal tumors (72%). These findings suggest that p53 may be a target of chromosome 17 deletions and that this gene may play a role in the malignant transformation of adenomas. BglII and AccII restriction fragment length polymorphism analysis of the p53 gene may be a useful and direct technique to detect allelic loss of this gene in tumors.
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PMID:Loss of heterozygosity of p53 gene and p53 protein expression in human colorectal carcinomas. 186 64

The proliferation of alveolar macrophages in 47 patients with pulmonary sarcoidosis was investigated using immune peroxidase stains with the monoclonal antibody Ki-67. In patients suffering from sarcoidosis, a significantly elevated number of Ki-67-positive alveolar macrophages was observed. The number of proliferating alveolar macrophages showed a significant positive correlation both with the number of lymphocytes in the BAL fluid and with the T4/T8 quotient in the BAL fluid of sarcoidosis patients.
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PMID:[Proliferation of alveolar macrophages in pulmonary sarcoidosis correlates with markers of lymphocyte activity in bronchoalveolar lavage fluid]. 197 97

A permanent malignant meningioma (MM) cell line of the human brain designated "IOMM-Lee" is reported. This cell line was successfully established from the tumor of a 61-year-old Chinese man with repeated recurrent primary intraosseous malignant meningioma of the skull. It has been subcultured for more than 60 passages during the past 30 months. The doubling time of cultured cells is approximately 62 hours. Tumorigenicity in athymic nude mice (Balb/c-nu/nu) who develop multiple pulmonary metastases was observed; the doubling time of tumor volume in vivo is approximately 5 days. Karyotypic analysis revealed this cell line to be of human origin and near-diploid, with a modal chromosome number of 49. The mesenchymal tumor marker vimentin and intracytoplasmic microfilaments were identified in the cytoplasm of tumor cells by indirect immunohistochemical peroxidase-anti-peroxidase assays and immunogold ultrastructural localization by transmission electron microscopy, respectively. Scanning electron microscopy of cultured cells and xenografted tumors revealed ellipsoidal or carrot-shaped tumor cells presenting a wrinkled surface with short sparse microvilli. Potential proliferating activity was determined by Ki-67 monoclonal antibody; the Ki-67 labeling index of cultured cells and xenografted tumors was approximately 36% and 30%, respectively. This newly established malignant meningioma cell line of the human brain may prove useful as a research model.
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PMID:Characterization of a newly established malignant meningioma cell line of the human brain: IOMM-Lee. 223 31

Using the monoclonal antibody Ki-67, proliferating cells were demonstrated immunohistochemically in 16 tumors of the nervous system in children, and these findings compared with those in 44 adult tumors. The antibody, which reacts with a nuclear protein expressed during the G1, S, G2, and M phases of the cell cycle, was demonstrated in frozen (13 cases) or smear (3 cases) sections using the peroxidase-antiperoxidase method. The percentage of stained tumor cells in children was in general agreement with the histological grade, ranging from 0.2% in a schwannoma to 12.4% in a juvenile type of glioblastoma. In a medulloblastoma, the fraction of labeled nuclei was 10.2%. In malignant gliomas of children, the percentage of stained cells did not differ from that in adult tumors. However, some cases demonstrated an unusually higher number of positive cells associated with higher cellularity than did adult tumors; this is in agreement with the content of small immature tumor cells in many pediatric tumors. The use of Ki-67 staining could become an important additional criterion for predicting the biologic behavior of nervous system neoplasms in children.
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PMID:The use of the monoclonal antibody Ki-67 in determination of the growth fraction in pediatric brain tumors. 245 70

Using Ki-67 monoclonal antibody to the nuclear antigen of proliferating cells, the squash preparations of 141 brain tumors and the 36 frozen sections from corresponding tumor tissues were stained with peroxidase-antiperoxidase method. The staining indices in squash preparations correlated well to those in the corresponding frozen sections. There were good correlations between the percentage of stained cells and the histologic grade in agreement with known biologic behavior. In order of decreasing malignancy, the averages of Ki-67 staining indices were 26.7% for metastatic carcinomas, 12.6% for glioblastomas, and less than 2.8% for benign mesodermal tumor groups. Ki-67 staining with squash preparations could be applied to small tissues obtained by transsphenoidal surgery and stereotactic surgery as valuable adjuncts to intraoperative histologic diagnosis and the estimation of histologic malignancy.
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PMID:[KI-67 PAP stain for histologic grading of brain tumors by squash preparations]. 247 Apr 1


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