Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.23.5 (cathepsin D)
 4,130 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We conducted a trial in 42 benign and malignant meningiomas to assess a possible influence of preoperative dexamethasone therapy on mitotic index, labelling indices of proliferating cell nuclear antigen (PCNA), progesterone receptor, epidermal growth factor receptor (EGF-R), c-erbB-2 oncoprotein, cathepsin D, gamma-gamma enolase as well as the mean number of silver-stained nucleolar organizer region-associated proteins (AgNORs). Tumors with preceding dexamethasone therapy for more than 1 day display significantly less immunohistochemical staining for PCNA. A correlation between the labelling index of PCNA and the degree of malignancy could not be identified. There was no significant effect of preoperative dexamethasone therapy on the other parameters. Our data suggest that dexamethasone may selectively inhibit the expression of PCNA in the G1/S-phase of the cell cycle. Thus, we emphasize the necessity to heed factors, e.g. dexamethasone, which may affect the expression of proliferating markers.
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PMID:Influence of preoperative dexamethasone therapy on proliferating cell nuclear antigen (PCNA) expression in comparison to other parameters in meningiomas. 136 Aug 48

17 beta-Estradiol stimulates the secretion of the 34- and 52-kDa protein (i.e., cathepsin D and procathepsin D, respectively) from MCF-7 human breast cancer cells and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibits this estrogen-stimulated response. A comparison of the effects of 17 beta-estradiol, TCDD, and their combinations on the secretion of these two proteins was determined using four different assay procedures, namely autoradiographic analysis of the 35S-labeled proteins (from [35S]methionine) separated by polyacrylamide gel electrophoresis (PAGE), densitometric analysis of the silver- and double-stained proteins separated by PAGE, and radioimmunoassay of the proteins using commercially available antibodies to the 52-kDa protein. The results showed that the autoradiographic, staining, and radioimmunoassay procedures gave comparable results with only a few minor differences in the relative amounts of the 52-kDa detected in the various treatment groups. In the medium obtained from 17 beta-estradiol-treated cells that was serially diluted, there was an excellent linear correlation for the relative concentrations of the 52-kDa protein using the double-staining/densitometric procedure and the radioimmunoassay. These results indicate that the double- or silver-staining method may be a useful and rapid method for screening new compounds as antiestrogens in MCF-7 cells.
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PMID:Development of gel staining techniques for detecting the secretion of procathepsin D (52-kDa protein) in MCF-7 human breast cancer cells. 138 Nov 55

Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease.
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PMID:Abnormal distribution of cathepsins in the brain of patients with Alzheimer's disease. 179 81

The ultrastructural cytochemical reactivity, renin activity, and cathepsin D activity of atria and ventricle of the bullfrog have been assessed. The specific granules (A, B, and D) were found to be argentaphobic when ultrathin sections of Araldite-embedded atria and ventricle were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. The entire core of the specific granules was moderated positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate embedded atria and ventricle were stained by phosphotungstic acid at a low pH. A similar reaction was shown by the cell coat, intercalated discs, residual bodies (C granules), and Z discs as well as by a very small portion of the Golgi complex. Incubation of ultrathin sections of atria and ventricule fixed only in glutaraldehyde and embedded in glycol methacrylate with either pronase or trypsin resulted in selective digestion of specific granules and Z discs and, to a much lesser degree, of the cell coat. As cathepsin D activity and renin activity were present in both atria and ventricle, the generation of angiotensin I by these cardiocytes might have been due to either enzyme. Nevertheless, because of the glycoprotein nature of specific granules and of the endocrinelike ultrastructure of atrial and ventricular cardiocytes in the frog, the present results raise the possibility that specific granules may contain renin.
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PMID:Ultrastructural cytochemistry of atrial and ventricular cardiocytes of the bullfrog (Rana catesbeiana). Relationship of specific granules with reninlike activity of the myocardium. 701 73

Plaque-like lesions and amyloid angiopathy were investigated in the frontal cerebral cortex of four patients with hereditary cerebral hemorrhage with amyloidosis (Dutch) (HCHWA-D), using immunohistochemical [antibodies to beta amyloid protein (A beta), beta protein precursor (beta PP), synaptophysin, ubiquitin (UBQ), cathepsin D, paired helical filaments (PHF) and glial fibrillary acidic protein (GFAP)], enzymehistochemical (acid phosphatase) and silver [methenamine silver (MS) and Palmgren] staining methods. Whereas A beta- and MS-positive diffuse plaques were found in all patients, only the three older patients showed neuritic or congophilic plaques, which were acid phosphatase and cathepsin D positive and contained beta PP-, synaptophysin- and UBQ-positive, but PHF-negative neurites. These plaques were surrounded by reactive astrocytes. Similar immuno- and enzymereactivity was found around congophilic blood vessels. Thus, apart from neuronal degeneration in a subset of plaque-like lesions and around blood vessels, this study shows an age-related morphology of the plaques in HCHWA-D, corresponding to that in Down's syndrome (DS), with the difference that neurofibrillary (NF) pathology is absent in HCHWA-D in contrast to DS. HCHWA-D may be considered as a model for congophilic plaque formation not associated with NF pathology.
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PMID:Hereditary cerebral hemorrhage with amyloidosis (Dutch): a model for congophilic plaque formation without neurofibrillary pathology. 783 31

A series of 200 breast carcinomas was investigated on frozen sections using PAb 1801 p53 monoclonal antibody and streptavidin biotin peroxidase complex. Densitometric analysis of the immunoprecipitates was assessed by processing digitized microscopic images. p53 was observed in the nucleus of 48% of the tumors. Some tumors (14 of 91) tested in parallel on paraffin sections were negative, although positive on frozen sections. Image analysis showed that the surfaces positive with anti-p53 and the staining intensity were decreased (P < .01) on paraffin sections. The p53 tumor expression was independent of patient age, tumor size, axillary lymph node status, HER-2/neu and cathepsin D expression, and nuclear morphometric parameters. However, p53 correlated with high histological grade (P < .01), lack of estrogen receptor (ER) (P = .0015) and progesterone (PR) (P = .0065) antigenic sites, pS2 detection (P = .03), high Ki-67 immunoreactivity (P = .018), large silver-stained nucleolar organizer region (AgNOR) nuclear surface ratio (P < .02), and degree of hyperploidy (P < .03), and was more often observed in the comedocarcinomas. The results suggest that p53 expression in breast carcinomas is not a totally independent prognostic indicator and that the clinical relevance and prognostic significance of p53 expression in breast carcinomas can be reliably assessed provided that the procedures are standardized, particularly with regard to the use of frozen sections and image analysis processing of the immunodetection.
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PMID:p53 quantitative immunocytochemical analysis in breast carcinomas. 786 46

A simple procedure for the affinity purification of procathepsin D from tissue culture medium conditioned by breast-cancer cells is described. This procedure yielded 2 micrograms of procathepsin D/100 ml medium. The procathepsin D was approximately 95% pure as judged by silver staining of polyacrylamide gels, the major contaminant being mature cathepsin D. The ability of procathepsin D to stimulate the proliferation of oestrogen-responsive MCF-7 breast cancer cells was determined. The purified procathepsin D had no mitogenic effect alone or in combination with oestradiol or other growth factors. These data suggest that procathepsin D does not act as an oestrogen-regulated autocrine growth factor for malignant breast epithelial calls.
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PMID:Mitogenic activity of procathepsin D purified from conditioned medium of breast-cancer cells by affinity chromatography on pepstatinyl agarose. 766 21

Scavenger receptor-mediated processing by rat liver endothelial cells in vivo is studied by using acetylated and oxidized low-density lipoproteins (LDL) as ligands. The cellular localization of acetylated LDL (Ac-LDL) is visualized by both immunohistochemistry and silver enhancement of ultrasmall gold particles conjugated to Ac-LDL. Scavenger receptor-mediated internalization by the endothelial cells only involves coated vesicle formation. Subsequently, three stages of processing are noticed, as represented by (i) large electron lucent vesicles, with ligand in close association to the membrane, (ii) relatively electron-lucent structures, with Ac-LDL dispersed over the vesicular lumen, while tubular membrane extensions did not contain ligand, and (iii) electron-dense vesicles in which the nondegradable gold particles of the conjugate accumulate, while the immunoreactivity for Ac-LDL is low. Addition of chloroquine, an inhibitor of lysosomal degradation, demonstrated that the relatively electron-lucent and electron-dense structures represent subsequent stages of the lysosomal pathway of Ac-LDL, which was also verified by detection of the lysosomal enzyme cathepsin D. Evaluation of the processing of Ac-LDL and oxidized LDL, labeled with different fluorochromes, demonstrated that both ligands follow apparently the same intracellular pathway in the liver endothelial cells, since the fluorescent probes are predominantly localized in the same structures. It is concluded that the scavenger receptor-mediated processing of modified LDL by rat liver endothelial cells involves four morphologically distinguishable stages which represent a highly effective catabolic route, sustaining the important role of the liver endothelial cells in the protection against circulating atherogenic lipoproteins.
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PMID:Morphological characterization of scavenger receptor-mediated processing of modified lipoproteins by rat liver endothelial cells. 826 98

Melanomas exhibiting mutated ras genes are frequently invasive and amelanotic. Transfecting melanocytes with ras oncogenes causes transformation and a loss of visible pigmentation. We analyzed murine melanocytes rendered amelanotic by transfection with the v-rasHa oncogene. Consistent with previous reports, tyrosinase and tyrosinase-related protein-1 (TRP-1) were not expressed by transformed cells. In addition, lack of expression of TRP-2 and the product of the silver locus was documented. Levels of melanosomal matrix antigens, the pink-eyed dilution locus protein and lysosome-associated membrane protein-1 were markedly reduced. Residual matrix antigens were localized by immunofluorescence to large vacuoles distributed peri-nuclearly in transfected cells. Electron microscopy demonstrated the absence of typical melanosomes and the presence of large vacuolar structures, also in a peri-nuclear distribution. Although levels of lysosomal hydrolases, such as beta-glucuronidase and cathepsin D, were diminished, marked elevations were observed in the expression of cathepsins B and L, 2 thiol proteases implicated in the acquisition of invasiveness. Our data demonstrate that transfection of melanocytes with v-rasHa is sufficient to disrupt the biogenesis of melanosomes and to up-regulate thiol protease synthesis, providing insights into the amelanotic and invasive nature of melanomas exhibiting mutations in ras genes.
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PMID:Melanosomal and lysosomal alterations in murine melanocytes following transfection with the v-rasHa oncogene. 863 74

An improved technique is described that addresses the problems of sensitivity, specificity, the use of hazardous radioactive equipment and time consumption in immunohistochemical labelling and double labelling of in situ hybridization of tissue specimens. It consists of a two-step protocol in which digoxigenin-uridine triphosphate (UTP) labelled riboprobes in the in situ hybridization step are visualized by the immunogold-silver staining method, and double labelling of tissue antigens is achieved by the application of an alkaline phosphatase-anti-alkaline phosphatase staining step. We tested this protocol using snap-frozen tissue sections of synovial tissue from patients with rheumatoid arthritis. The target mRNA was detected by perforin or cathepsin D riboprobes, the double labelling was performed using anti-collagen type IV and alpha-smooth muscle actin antibodies. It is concluded that, in comparison with an established three- to four-day double-labelling protocol used in many laboratories, this one-day combination is currently the most rapid assay of reliable quality for double labelling of in situ hybridization products and tissue antigens.
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PMID:A one-day double-labelling technique for tissue specimens: immunogold-silver staining for in situ hybridization combined with alkaline phosphatase-anti-alkaline phosphatase (APAAP) immunohistochemistry for antigens. 880 Dec 22


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