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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The methodologic prerequisites of cytophotometric DNA measurements of normal and tumor cells in tissue sections obtained from paraffin blocks and preserved as archival material were investigated. The optimal time of hydrolysis in 5-N HCl at room temperature was one hour for the different cell types analyzed. Paraffin-embedded tissues, stored for two decades, were still suitable for quantitative cytophotometric DNA determinations of Feulgen-stained nuclei. Different cell types in the Feulgen-stained sections could be identified with accuracy. The 90th percentile of fibroblast (internal control cells) DNA values was used as an upper limit of the diploid DNA content. By determining the number of tumor cells with DNA values exceeding this limit, nondiploid (hyperploid) tumor cell populations could be discriminated from diploid tumor cell populations. Cell population analysis of ploidy level, performed in this way, was found to be accurate in tissue sections of 4 micrometer. The accuracy of this analysis was not improved by increasing the section thickness. Since tissue sections obtained from old paraffin blocks could be used for the determination of hyperploidy, the prognostic significance of this parameter in different tumors can be assessed retrospectively.
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PMID:Cytophotometric DNA measurements of chondrosarcoma: methodologic aspects of measurements in tissue sections from old paraffin-embedded specimens. 616 Jul 95

Paraffin-embedded sections from a variety of epidermal lesions were stained with fluorescein isothiocyanate-labeled concanavalin A and examined by a fluorescence microscope. Seventy-six normal, hyperplastic, and neoplastic tissues were examined. Lectin binding was demonstrated in all malignant tumors, the fluorescence being confined to the plasma membrane of the tumor cells. Normal and hyperplastic tissues either failed to stain or showed a grossly diminished level of fluorescence. The distinction between malignant and normal of hyperplastic cells was clear-cut and definite.
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PMID:Lectin-binding affinities of human epidermal tumors and related conditions. 616 35

Paraffin-embedded tissues from 15 women with breast or endometrial carcinomas were analyzed in a study designed to explore the possible value and validity of an immunoperoxidase method for the detection of estrogen receptor in formalin-fixed paraffin-embedded tissue. Results were compared with biochemical assays for estrogen receptor performed on cytosols of fresh tissue from the same patients. There was complete correlation in nine of 15 (60%) of the tumors analyzed. Four cases (26.7%) were judged positive for estrogen binding sites by immunoperoxidase but were negative for estrogen receptor by biochemical assays; in two cases the converse was observed. The immunohistologic technique is relatively rapid and utilizes fixed paraffin sections of the same tissue that is used for standard histologic diagnosis. The provision of a permanent record that can be kept for future reference provides an advantage over immunofluorescence methods that have been advanced for the detection of estrogen receptors. The excellent morphology achieved permits an assessment of the staining of individual cells in relation to the usual histologic criteria employed in the diagnosis of breast and endometrial cancer. This stands in contrast to biochemical cytosol-based assays that take no account of variations in receptor expression by the tumor cells or variations in the proportion of the assayed material that is in fact neoplastic as distinct from supporting stroma and connective tissue.
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PMID:Detection of estrogen receptor in breast and endometrial carcinoma by the immunoperoxidase technique. 616 43

Antibodies specific for bovine ribonuclease A (antiRNase A) were raised in rabbits, and immunologic cross-reactivity between bovine RNase A and human salivary gland RNase was demonstrated. The antiRNase A served as the primary antibody in the peroxidase-antiperoxidase immunohistochemical technique. Paraffin blocks of five normal human parotids and 20 parotid tumors were examined. In normal parotid and in cases of cystadenoma lymphomatosum, immunoreactive RNase was localized in the ductal epithelium, evidence of the ductal cell origin of these benign tumors. RNase immunoreactivity was noted in the adenomatous structures and in cells isolated in the myxoid matrix of pleomorphic adenomas, which supports recent evidence of an epithelial origin of these tumors. Malignant acinar cells of acinic cell carcinoma were strongly positive for immunoreactive RNase, while acinar cells of normal parotid were uniformly negative. This expression of the gene for RNase A probably represents a loss of differentiation (i.e., control) of the neoplastic acinar cells. Further evidence for this hypothesis was obtained by treating these tumors with an antihuman salivary amylase antibody, which is localized in normal acinar cells. No immunoreactive amylase was observed. The results support the idea that immunoreactivity need not accompany enzyme activity, as the presence of immunoreactive RNase was noted in all neoplastic tissues examined. Immunohistochemical localization of two antigens in the same tissue demonstrates the varied biochemical changes associated with parotid neoplasia.
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PMID:Immunohistochemical demonstration of ribonuclease and amylase in normal and neoplastic parotid glands. 619 82

Hepatoma cells isolated from rats after administration of a carcinogen, diethylnitrosamine, and propagated in culture, contained a genetically stable cytoskeletal abnormality resembling Mallory bodies. These juxtanuclear aggregates of intermediate-sized filaments were maintained in carcinomas produced in nude mice after inoculation of uncloned mass cultures and a cloned subculture. Paraffin and frozen sections of these tumors revealed acentric nuclei and a glassy hyalin-type cytoplasmic lesion which stained pink with hematoxylin-eosin and blue with Mallory's aniline blue stain. The cells in culture and in the tumor sections were strongly positive for gamma-glutamyl transpeptidase. Cryostat sections examined by indirect immunofluorescence microscopy with antisera to purified bovine hoof prekeratin, desmosome-associated tonofilaments from bovine muzzle, and murine vimentin, as well as transmission electron microscopy revealed the presence of juxtanuclear aggregates of intermediate-sized filaments. All characteristics previously reported for the tissue culture cell line were stably maintained in the tumor tissue. These results suggest that the Mallory body-containing cells frequently observed in man in alcoholic hepatitis and other degenerative liver diseases could, under appropriate environmental "promoting" conditions, be precursor cells in focal hepatocellular carcinoma formation.
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PMID:Mallory body-like abnormalities in carcinomas induced by cultured transformed rat liver cells. 627 81

Paraffin-embedded sections of 11 alveolar and 12 embryonal rhabdomyosarcomas, 12 lymphomas, five neuroblastomas, five extraskeletal neoplasms resembling Ewing's sarcoma, and six epithelial tumors were tested for immunoreactivity against myosin, myoglobin, and isozymes BB and MM of creatine kinase with a peroxidase-antiperoxidase method. Of the 23 cases of rhabdomyosarcomas 17 were positive for at least three of the antigenic determinants. In contrast, the other investigated tumors were consistently negative for all markers, with the exception of breast and prostatic carcinomas. Our results establish that the presence of three or four of the above markers in a tumor is strongly suggestive of a rhabdomyosarcoma and helpful in the distinction of alveolar and embryonal rhabdomyosarcomas from lymphomas, neuroblastomas, and extraskeletal neoplasms resembling Ewing's sarcoma.
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PMID:Immunohistochemical study of alveolar and embryonal rhabdomyosarcoma. 633

Paraffin-embedded sections from a variety of breast lesions were stained with a number of lectins labeled with fluorescein isothiocyanate and examined by fluorescence microscopy: 95 non-neoplastic tissues and 69 malignant tumors were examined. Lectin binding was demonstrated in all malignant tumors, the fluorescence being confined to the plasma membrane of the tumor cells. Normal and hyperplastic tissues either failed to stain or showed a grossly diminished level of fluorescence. The significance of the staining reaction is discussed.
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PMID:Lectin-binding affinities of human breast tumors. 641 23

Mouse peritoneal macrophages (MPM) from C57BL/6J, BALB/c, A strains, and (BALB/ cfemale X C57BL/ 6Jmale )F1 offspring were treated with the oxidative burst (OB)-stimulant 12-O-tetradecanoylphorbol 13-acetate, and their in vitro tumoricidal, tumorostatic , and OB activities were examined. Paraffin oil-elicited, but not thioglycollate (TG)-elicited, MPM exhibited cytotoxicity only toward Yac-1 cells and cytostatic activity toward Yac-1, EL 4, RBL-5, and RLmale 1 lymphoma cells. This activity was in correlation with the reduced capacity of TG-elicited cells to generate OB products. The toxic effect of such activated MPM was partially inhibited by catalase, superoxide dismutase, cytochrome c, and vitamin E (alpha-tocopherol) and was augmented by horseradish peroxidase and the catalase inhibitor aminotriazole (3-amino-1H-1,2,4-triazole), thus indicating the involvement of oxygen-derived toxic reagents, mainly hydrogen peroxide, in the MPM-mediated damage inflicted on the tumor cells. EL 4 cells incubated with nonstimulated MPM exhibited enhanced growth both in vitro and in vivo, whereas OB-stimulated MPM inhibited the growth of such cells in the same experimental systems.
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PMID:Oxidative burst-dependent tumoricidal and tumorostatic activities of paraffin oil-elicited mouse macrophages. 658 55

Male Wistar rats weighing 100 g received 1,2-dimethylhydrazine (25 mg/kg) s.c.) twice a week for 2 months and once a week thereafter for an additional 4 months. Groups of four to six rats were sacrificed monthly. Paraffin sections of duodenum were prepared and stained with periodic acid-Schiff and hematoxylin for cell counts and with toluidine blue for measuring nucleolar area. As an index of villus size and crypt size, the mean number of epithelial cells per representative sections of villi and crypts were used. Mitotic activity was assessed by counting the mean number of mitotic figures per representative crypt section. Nucleolar area was assessed from the analysis of drawn (camera lucida) images of nucleoli of columnar cells at six levels of the epithelium: lower, mid, and upper parts of the crypts and villi. Villus size increased progressively during the 6-month treatment, from 272 +/- 2 (S.E.) to 349 +/- 8. Crypt size increased from 118 +/- 2 in a wavy fashion, showing maximum (139 +/- 5, 143 +/- 2) at 3 and 6 months and minimum (123 +/- 3, 127 +/- 1) at 1 and 4 months. Mitotic number displayed a similar pattern of increase so that the percentage of mitotic figures in the crypts (mitotic index) remained constant (about 5%) in control and experimental animals. Nucleolar area in the controls decreased with age from 4.2 +/- 0.08 sq micron in lower crypt at 1 month to 2.8 +/- 0.04 sq micron at 6 months. During 1,2-dimethylhydrazine treatment, lower crypt nucleoli increased to 4.5 +/- 0.12 sq micron after 3 months and decreased slightly thereafter, reaching 4.0 +/- 0.14 sq micron by the sixth month. The nucleoli furthermore decreased gradually along epithelium (nucleolar compaction) by an average of 0.23% per cell position in control as well as treated animals. It appeared, then, that the main effect of 1,2-dimethylhydrazine was the enlarging of the four parameters measured. This effect seemed to relate in some manner to tumor formation as all the enlargements were attenuated in intestinal tissue adjacent to tumors.
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PMID:Morphometric study of the rat duodenal epithelium during the initial six months of 1,2-dimethylhydrazine carcinogenesis. 688 38

We have developed a new immunoperoxidase "sandwich" staining method for amplified detection of P-glycoprotein (Pgp) that is suitable for use on formalin-fixed, paraffin-embedded (conventional) tissue sections. This was accomplished by substantially changing the procedure described by Chan (1988) so as to increase specific staining intensity and to decrease nonspecific background staining. To determine the most appropriate primary antibody for the assay, we compared the immunoreactivity of JSB-1, C494, and C219 monoclonal antibodies recognizing internal epitopes of Pgp, and MRK16 and 4E3 monoclonal antibodies recognizing external epitopes of Pgp. Paraffin sections of Pgp-positive normal human tissues (adrenal, liver, kidney, and brain), of renal tumors, and of cell pellets of sensitive and multidrug resistant human tumor cell lines (MCF-7, KB) were used for comparisons. Immunostaining was excellent with JSB-1, moderate with C494, and very weak with C219. MRK16 and 4E3 showed no reaction. Nonspecific background staining was reduced by 1) omitting immunoglobulin G from secondary antibodies; 2) decreasing the concentration of peroxidase-antiperoxidase complex; and 3) utilizing casein solution for blocking and washing. Pretreatment of sections before immunostaining was also simplified. Using JSB-1, the threshold for detection of elevated Pgp corresponded to less than two-fold relative resistance to doxorubicin. Applying this method, we found two of 26 non-small cell lung cancers were positive for Pgp, consistent with previous results of others using frozen sections. This new immunoperoxidase sandwich staining method using JSB-1 now allows reliable Pgp detection in sections of formalin-fixed, paraffin-embedded (archived) surgical specimens and small biopsy materials commonly used for diagnostic purposes.
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PMID:New immunohistochemical "sandwich" staining method for mdr1 P-glycoprotein detection with JSB-1 monoclonal antibody in formalin-fixed, paraffin-embedded human tissues. 750 82


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