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

Hyaline droplet nephropathy in male rats due to alpha 2u-globulin accumulation in proximal tubules is caused by chemicals from several chemical classes. We have previously shown that the well-known sedative/hypnotic barbiturate, sodium barbital, and its breakdown product, diethylacetylurea, are renal toxins and renal tumor promoters. To determine comparative induction of hyaline droplets in renal tubules by sodium barbital and diethylacetylurea, male F344/NCr rats, 6 weeks of age, were given diets containing 0, 170, 341, 500, or 1000 ppm of diethylacetylurea or containing 500, 1000, or 4000 ppm of sodium barbital for periods of 2 or 10 weeks. Rats were terminated at 2 or 10 weeks and the histology of the kidney was evaluated using light microscopy with hematoxylin and eosin staining and staining by the Heidenhain method. Quantitative analysis showed dose responses for the degree of droplet accumulation in the P2 and P3 segments of the proximal tubules. Diethylacetylurea was more potent. Immunohistochemistry and ultrastructural evaluation revealed the nature of the droplets. Western blotting confirmed the presence of alpha 2u-globulin. Renal tubular necrosis, regeneration, and increased levels of cell proliferation using proliferating cell nuclear antigen immunohistochemistry were also found. Female rats similarly exposed to each chemical did not show tubule droplet accumulations nor renal lesions. We confirm for the first time that these two chemicals can be added to the enlarging list of nephrotoxic chemicals inducing alpha 2u-globulin nephropathy and possessing tumor promoting and renal carcinogenic properties.
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PMID:Comparative hyaline droplet nephropathy in male F344/NCr rats induced by sodium barbital and diethylacetylurea, a breakdown product of sodium barbital. 751 96

Differentiation of periosteal osteosarcoma and parosteal (periosteal) chondrosarcoma by conventional histology may be difficult. One case each of clinically and histologically proven periosteal osteosarcoma and parosteal chondrosarcoma were evaluated by a double-immunohistochemical staining method using proliferating cell nuclear antigen (PCNA) and S-100 protein (S-100). Conventional histology showed proliferation of both osteoblastic and chondroblastic cells in the periosteal osteosarcoma, while there was a growth of only chondroblastic tumor cells in the parosteal chondrosarcoma. Immunohistochemical studies indicated that the nuclei of chondroblastic cells recognized by S-100 were PCNA-negative, while osteoblastic stromal cells were PCNA-positive in the periosteal osteosarcoma. In contrast, chondroblastic cells in the parosteal chondrosarcoma were both S-100- and PCNA-positive. Our findings suggest that periosteal osteosarcoma is characterized by the proliferation of osteoblastic stromal cells, whereas parosteal chondrosarcoma is characterized by the proliferation of chondroblastic cells. This method of double immunohistochemical staining, using PCNA and S-100, may be useful in differentiating these chondroblastic tumors.
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PMID:Periosteal osteosarcoma and parosteal chondrosarcoma evaluated by double immunohistochemical staining. Report of 2 cases. 751 93

The usefulness of proliferating cell nuclear antigen (PCNA) immunostaining for estimating the growth fraction in glial tumors was evaluated in ethylnitrosourea-induced rat gliomas. The PCNA labeling index was compared with the bromodeoxyuridine (BrdU) labeling index, using alternate serial sections fixed either in 10% formalin or in periodonate-lysine-paraformaldehyde (PLP). The PCNA labeling index was significantly correlated with the BrdU labeling index if cells with only faint PCNA staining were excluded. Differences in PCNA staining were noted between the two fixatives. The number of PCNA-positive cells in PLP-fixed material was greater than in 10% formalin-fixed material, but showed a poorer correlation with BrdU labeling index. Over-fixation in formalin reduced the number of positive cells. Although peritumoral tissue did not exhibit overexpression of PCNA, the ependymal lining was weakly stained even in areas distant from the tumor. PCNA labeling index is a useful method to estimate the growth fraction when the materials are processed in a controlled way. When clinical specimens with uncertain preparation are used, care is required in interpreting the results.
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PMID:Proliferating cell nuclear antigen expression in rat glioma model: comparison with bromodeoxyuridine labeling index. 751 46

The proliferative activity of male breast carcinoma has been investigated using the staining of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody against the proliferating cell nuclear antigen (PC10) and the monoclonal antibody MIB-1 in formalin-fixed, paraffin-embedded specimens from 27 primary male breast carcinomas at diagnosis. A significant correlation was found between survival and AgNOR counts (median of survival 77 months for cases with AgNOR/cell < or = 7.27 but 37 months only for cases with > 7.27 AgNOR/cell; P = 0.001), proliferating cell nuclear antigen scores (median of survival 73 months for cases with proliferating cell nuclear antigen < or = 18.25% versus 41 for cases with proliferating cell nuclear antigen > 18.25%; P = 0.013) and MIB-1 scores (median of survival 73 months for cases with MIB-1 scores < or = 23.5% versus 37 months for cases with MIB-1 scores > 23.5%; P = 0.01). Tumor histological grade was also correlated with prognosis (median of survival 72 months for grade 2 versus 33 months for grade 3 tumors; P = 0.01). Estrogen and progesterone receptors, immunohistochemically detected on paraffin-embedded sections, had no prognostic value. In the multivariate survival analysis, only AgNOR counts (P = 0.007) and tumor size (P = 0.003) had an independent prognostic significance. Our results indicate that methods for assessing the cell proliferation in routinely processed specimens offer significant prognostic information in male breast carcinoma. The finding, together with the lack of prognostic significance for estrogen receptors and progesterone receptors, suggests that male breast carcinoma is biologically different from female breast cancer.
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PMID:Proliferative activity is a significant prognostic factor in male breast carcinoma. 751 30

A total of 14 cases of clear cell carcinoma of salivary glands were evaluated by immunohistochemical methods using monoclonal antibodies to cytokeratin (K1.1 and K8.12), vimentin, S-100 alpha and beta subunits, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), MAM-3 and MAM-6 antigens and proliferating cell nuclear antigen (PCNA), as well as polyclonal antibodies to lysozyme (Ly), lactoferrin (la) and Alpha-1-antichymotrypsin (alpha 1-Ach). Histopathologically, the carcinoma was characterized by round or polygonal tumor cells with cytoplasm that does not stain with hematoxylin and eosin, nuclei with little pleomorphism and few or no mitotic figures, and growing in solid sheets, small nests or cords with collagenous stroma. Cytokeratin KL1 and K8.12 was present in few tumor cells with almost negligible to strong reaction in all cases, vimentin in 6, GFAP in 5 cases with multiple-expression of cytokeratin K8.12, vimentin and GFAP in 5 cases. S-100 protein immunoreactivity was the most prominent feature with more intense reaction of S-100 beta than S-100 alpha subunit. NSE reactivity was seen in 6 cases. Ly, La, a1-ch, MAM-3 and MAM-6 antigens were localized in clear cells with various reaction intensities. The authors conclude that the clear tumor cells in clear cell carcinoma of salivary glands are not myoepithelial in origin but epithelial or neuroectodermal/neural crest in origin, showing ductal differentiation at the immunohistochemical level.
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PMID:Clear cell carcinoma of salivary glands: immunohistochemical evaluation of clear tumor cells. 752 Nov 53

Neovascularization in the walls of coronary arteries is associated with the presence of atherosclerotic plaque. The mechanisms responsible for the formation of these intraplaque microvessels are not understood. The purpose of this study is to examine the prevalence of endothelial cell replication in plaque microvessels. Two hundred and one primary and restenotic coronary atherectomy specimens were analyzed for the presence of microvessels and proliferation as reflected by positive immunolabeling for Ulex agglutinin and the proliferating cell nuclear antigen, respectively. In primary but not restenotic specimens, proliferation of any cell type was associated with the detection of microvessels on the same slide. However, intraplaque microvessels were more commonly found in restenotic compared to primary specimens (P = 0.004). Twelve highly vascularized specimens with evidence of replication were subjected to detailed histomorphological and quantitative image analyses. At 200 x, the most vascular optical field of each slide was identified and consistently included plaque macrophages. Total slide endothelial cell replication indices for these specimens varied, but in some instances were remarkably elevated (eg, 43.5%). The role of intraplaque angiogenesis may be analogous to that of tumor or wound angiogenesis and be important in development and progression of coronary artery lesions and restenosis.
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PMID:Angiogenesis in human coronary atherosclerotic plaques. 752 31

The reproducibility in quantitation of proliferation activity, determined using the monoclonal antibody 19A2 to proliferating cell nuclear antigen (PCNA), was tested in visual and computer-assisted analyses of brain tumor material. The PCNA labeling index was scored using count (PCNA-LI, visual and computer analyses) and area (PCNA-LIa, computer analysis) estimates of immunopositivity. The quality of immunostaining was the most important reason for variation in the assessment results. Other significant variation sources in the assessment were experience in selecting microscopic fields and distinguishing immunopositive nuclei from immunonegative ones. Computer-assisted analysis improved the reproducibility of quantitation between different observers (visual rPCNA-LI = 0.624 versus computer assisted rPCNA-LI = 0.904). Also, the use of PCNA-LIa improved the intraobserver and interobserver reproducibility in different stainings (observer 1:rPCNA-LI = 0.857 versus rPCNA-LIa = 0.874; observers 1 and 2: rPCNA-LI = 0.904 versus rPCNA-LIa = 0.927; observers 3 and 4: rPCNA-LI = 0.848 versus rPCNA-LIa = 0.906). PCNA-LIa by computerized image analysis improves accuracy in the evaluation of the granularly expressed PCNA level. Furthermore, the effect of tumor heterogeneity on the assessment results can be diminished with the computerized method because large tissue areas can be analyzed faster.
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PMID:Sources of variation in the assessment of cell proliferation using proliferating cell nuclear antigen immunohistochemistry. 752 16

The expression of proliferating cell nuclear antigen (PCNA) was immunohistochemically determined using a monoclonal antibody PC10 in 54 prostatic carcinoma samples. The samples were taken from needle biopsy specimens which had been paraffin-embedded after routine fixation with 10% formaldehyde solution (formalin) for less than 24 h. The PCNA index was calculated as the percentage of positive tumor cell nuclei. There was a significant difference in the PCNA index according to the growth pattern (p < 0.001), nuclear anaplasia (p < 0.001) and T stage (p < 0.01). Regarding the growth pattern, solid carcinomas showed a significantly higher PCNA index than did either separate gland carcinomas (p < 0.05) or trabecular/fused gland carcinomas (p < 0.05). The PCNA index correlated closely with either the nuclear anaplasia or T stage, and increased in conjunction with the increased nuclear anaplasia (rs = 0.641; p < 0.001) or T stage (rs = 0.435; p < 0.01). The patients in the high PCNA index (> or = 15%) group showed a significantly worse survival than did those in the lower PCNA index group (p < 0.01), and multivariate analyses indicated that the PCNA index had an independent prognostic significance. These results suggest that the PCNA index, as determined by PC 10 on needle biopsy specimens of prostatic carcinoma, can thus be an objective and quantitative means for evaluating the biological malignancy of prostatic carcinoma.
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PMID:Proliferating cell nuclear antigen in needle biopsy specimens of prostatic carcinoma. 752 94

The purpose of this study was to examine the relationship between natural killer cell activity and biological behavior of tumor, expressed by architectural (FIGO) and nuclear grading, depth of myometrial invasion, and proliferating cell nuclear antigen (PCNA) index in patients with endometrial carcinoma. Forty patients with FIGO stage I endometrial carcinoma, treated with radical surgery, were included in this retrospective study. At the time of diagnosis, natural killer cell activity of peripheral blood was evaluated against K562 target tumor cells and correlated with architectural and nuclear grading, depth of myometrial invasion, and PCNA index of the tumor. Natural killer activity diminished with increasing nuclear grade of the tumor (P = 0.004); similarly, natural cytotoxicity decreased with myometrial invasion: for stages IC and IB endometrial carcinoma, the mean values of natural cytotoxicity were significantly lower than stage IA disease (P = 0.0001). Natural killer activity was significantly correlated with PCNA immunostaining of the tumor (r = -0.8). It is concluded that the natural immune reactivity seems to be related to the pathologic features of early stage endometrial carcinoma, showing a significant reduction in presence of nuclear pleomorphism and/or myometrial invasion, and also an inverse relationship with PCNA index.
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PMID:Natural killer cell activity in stage I endometrial carcinoma: correlation with nuclear grading, myometrial invasion, and immunoreactivity of proliferating cell nuclear antigen. 752 25

In order to develop an in vivo model for growth of acoustic schwannomas, we studied tumor specimens from 10 patients, transplanted into a subcutaneous pocket of 67 nude mice. The number of tumors which survived or grew was 63 (94%). Obvious macroscopic growth was observed in 22 (33%), status quo in 28 (42%), and regression of tumor size in 13 (19%). The tumor disappeared in 4 cases (6%). Serial implantation was not possible due to the small amount of neuroma tissue in the surviving tumors. In animals with obvious macroscopic growth, neovascularization was clearly demonstrated. The presence of Schwann cells in the implants was confirmed immunohistochemically. The proliferative activity in the original and implanted tumors was evaluated by the proliferating cell nuclear antigen (PCNA) and Ki-67 nuclear antigen stainings and showed good correlation between primary tumors and implants. This in vivo tumor model will open new opportunities to study the biology of acoustic tumors and to test different therapeutic modalities.
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PMID:Subcutaneous growth of human acoustic schwannomas in athymic nude mice. 752 95


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