Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Protein complexes containing cyclins and cyclin-dependent protein kinases (cdks) have been shown to be rearranged in both spontaneous and viral tumor antigen-transformed cells. We have examined G1- and S-phase cyclin/cdk complexes as a function of the neoplastic progression of human diploid fibroblasts transfected with the SV40 large T antigen. We find that the expression of cyclin D1 and its association with proliferating cell nuclear antigen (PCNA) and Waf1 remain unchanged in precrisis human fibroblasts transfected with SV40 large T antigen. However, in these same cells the association of cdk4 with cyclin D1, PCNA, and Waf1 is disrupted. Upon immortalization, cyclin D1 protein expression is decreased, and binding of both PCNA and Waf1 with the remaining cyclin D1 is reduced. In contrast, large T antigen increased the expression of cyclin A and cyclin E proteins in both precrisis and immortal cells and did not reduce the binding of PCNA or Waf1 to either cdk2 or cyclin A proteins. These results show that large T-antigen expression in human fibroblasts selectively uncouples cyclin D1 from cdk4, and subsequent immortalization of these cells results in additional changes to the cyclin D1-dependent cell cycle regulatory pathways.
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PMID:Immortalization of human fibroblasts by SV40 large T antigen results in the reduction of cyclin D1 expression and subunit association with proliferating cell nuclear antigen and Waf1. 755 44

Thirty cases of hepatocellular carcinoma (HCC) were investigated immunocytochemically for expression of beta 1 integrin molecule and of collagen IV. Immunoreactivity was related to the tumour proliferation index, as detected by PCNA immunostaining, and to tumour size and grade. Membrane beta 1 integrin immunoreactivity was detected in the neoplastic cells of all cases, though two different staining patterns were clearly recognized. In 14 cases, beta 1 integrin immunoreactivity was confined to the cell-stroma interface, showing the same polarized pattern as the non-neoplastic cell counterpart. This staining pattern was associated significantly (P < 0.0001) with low PCNA labelling (i.e. less than 20 per cent of neoplastic cells showing nuclear immunostaining. Conversely, 16 cases showed non-polarized pericellular beta 1 integrin immunostaining. This staining pattern was significantly associated (P < 0.0001) with high PCNA labelling (more than 20 per cent of immunoreactive cells) and with tumour size greater than 4 cm in diameter (P < 0.0001). beta 1 Integrin, collagen IV, and PCNA immunoreactivities, however, did not correlate with the histological grade. The data emphasize that neoplastic progression of HCCs may be correlated with an aberrant expression of adhesion molecules and with a disruption of the collagen IV complement of basal membranes.
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PMID:Patterns of integrin common chain beta 1 and collagen IV immunoreactivity in hepatocellular carcinoma. Correlations with tumour growth rate, grade and size. 822 50

In vitro uptake of bromodeoxyuridine (BrdU), expression of proliferating cell nuclear antigen (PCNA), and expression of antigen Ki-67 as revealed by the MIB-1 antibody in fixed and embedded tissues have been regarded as markers of cell proliferation in colorectal tumor progression. Proliferation distribution abnormalities in high-risk mucosa have been illustrated in detail by BrdU labeling of cells in S phase, whereas PCNA and MIB-1 are less informative at this stage of carcinogenesis. The reliability of BrdU labeling is, in any event, dependent on optimization of its tissue uptake and diffusion. Neoplastic deregulation of the synthesis and expression of PCNA, coupled with striking variations in nuclear immunostaining intensity, imposes caution on its use as an intermediate biomarker in intestinal chemoprevention. Validation of MIB-1 must await the standardization of some of the critical procedures (e.g., treatment with microwaves) of antigen retrieval.
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PMID:Methodological aspects of using immunohistochemical cell proliferation biomarkers in colorectal carcinoma chemoprevention. 782 7

Morphometric, DNA, and proliferating cell nuclear antigen (PCNA) measurements were taken of benign melanocytic tumors and malignant melanomas. Significant differences between lesion groups according to Krushell-Wallis analysis were found in terms of mean nuclear area, coefficient of variation (cv) of nuclear area, cv of nuclear shape nuclear contour index (NCI), mean and cv of nucleolar area, DNA 2.5 c and 5 c exceeding rates, and PCNA positivity. A logistic regression analysis with respect to banal nevi versus primary malignant melanoma showed that the cv of nuclear area and the DNA 2.5 c exceeding rate were significant independent predictors. Nuclear polymorphism, i.e., the cv of nuclear shape NCI, was larger in metastasizing primary melanomas than in thin nonmetastasizing primary melanomas. PCNA positivity was occasionally increased in keratinocytes adjacent to nevi or melanomas. Larger values for nuclear area, DNA aneuploidy, and PCNA positivity were found in thick malignant melanomas and melanoma metastases than in benign melanocytic lesions and thin malignant melanomas. Morphometry, DNA content, and PCNA positivity thus seem to reflect different stages in tumor progression of malignant melanoma.
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PMID:Morphometric, DNA, and proliferating cell nuclear antigen measurements in benign melanocytic lesions and cutaneous malignant melanoma. 786 99

The morphology of the microcirculation of uveal melanomas is a reliable market of tumor progression. Scanning electron microscopy of cast corrosion preparations can generate three-dimensional views of these vascular patterns, but this technique sacrifices the tumor parenchyma. Formalin-fixed wet tissue sections 100-150 microns thick from uveal melanomas were stained with the lectin Ulex europaeus agglutinin I (UEAI) and proliferating cell nuclear antigen (PCNA) to demonstrate simultaneously the tumor blood vessels and proliferating tumor cells. Indocarbocyanine (Cy3) was used as a fluorophore for UEAI and indodicarbocyanine (Cy5) was used for PCNA. Double labeled sections were examined with a laser scanning confocal microscope. Images of both stains were digitized at the same 5-microns intervals and each of the two images per interval was combined digitally to form one image. These combined images were visualized through voxel processing to study the relationship between melanoma cells expressing PCNA and various microcirculatory patterns. This technique produces images comparable to scanning electron microscopy of cast corrosion preparations while permitting simultaneous localization of melanoma cells expressing PCNA. The microcirculatory tree can be viewed from any perspective and the relationship between tumor cells and the tumor blood vessels can be studied concurrently in three dimensions. This technique is an alternative to cast corrosion preparations.
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PMID:Three-dimensional relationships between tumor cells and microcirculation with double cyanine immunolabeling, laser scanning confocal microscopy, and computer-assisted reconstruction: an alternative to cast corrosion preparations. 790 12

Mutations in the p53 tumour suppressor gene, with consequent accumulation of the p53 protein, are frequently observed in non-small cell lung cancer (NSCLC). Little is known, however, about the timing of their appearance or their maintenance through cancer progression and metastatic spread. We have examined the normal epithelium and a panel of bronchial lesions, including dysplastic, neoplastic, and metastatic lesions, for p53 immunoreactivity and for expression of proliferating cell nuclear antigen (PCNA). No p53 immunoreactivity was found in normal and hyperplastic epithelium, nor in squamous metaplastic lesions. Twenty out of 30 invasive tumours and 13 out of 17 in situ carcinomas adjacent to an invasive tumour showed p53 immunoreactivity. There was a strict correlation between the level of p53 expression in the non-invasive and the invasive components of the tumours. Five out of eight pairs of primary tumours and matching metastases expressed p53, at identical levels in both compartments. These data indicate that p53 overexpression can occur in the earliest recognized phase of NSCLC and that the alteration is maintained during progression from in situ to invasive carcinoma and metastatic spread. PCNA expression increased from early to advanced phases of NSCLC. High PCNA immunoreactivity was observed in tumours expressing high p53 levels. A significant association was observed for PCNA expression between preinvasive and invasive lesions.
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PMID:Human non-small cell lung cancer: p53 protein accumulation is an early event and persists during metastatic progression. 767 94

In vitro uptake of bromodeoxyuridine and expression of proliferating cell nuclear antigen (PCNA) were evaluated histochemically in rectal mucosa of control subjects and subjects with colorectal neoplasia in large intestine adenomas and adenocarcinomas. Both labeling indices progressively increased along the path of tumor progression, as did the difference between them (PCNA labeling indices were always greater than those of bromodeoxyuridine). The correlation between them was fairly close in the controls and in adenomas with low-grade dysplasia, whereas no significant linear relations were noted in adenomas with high-grade dysplasia or in adenocarcinomas. The progressive increase in PCNA would thus seem to be related to both hyperproliferation and neoplastic deregulation of PCNA synthesis. In the mucosa of subjects with colorectal neoplasia, PCNA labeling revealed hyperproliferation but not the surface-wards shift of the proliferative compartment detected by bromodeoxyuridine. PCNA expression, therefore, is not a sufficiently sensitive marker of the risk of tumor transformation in the intestinal mucosa.
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PMID:Bromodeoxyuridine uptake and proliferating cell nuclear antigen expression throughout the colorectal tumor sequence. 810 91

The authors analyzed 13 central neurocytomas diagnosed at Seoul National University Hospital between January 1982 and December 1993 to clarify the proliferative potential and biological behavior of these tumors. The tumor was confined to the lateral and third ventricles in 12 cases and in one case extended from the posterior thalamus to the body and trigone area of the lateral ventricle. In all 13 cases, typical clinical and radiological findings were observed, and histological diagnosis was performed via craniotomy. The diagnosis was made using light microscopic examination, immunohistochemical staining for neuronal markers, and electron microscopic findings of neuronal differentiation. One patient died due to tumor progression with recurrence 26 months after subtotal removal plus radiation therapy. Another patient had a recurrence 18 months after total tumor removal. The remaining 11 patients are free of recurrent tumor after a follow-up period that ranged from 14 to 109 months (median 50 months). To predict the proliferative potential, immunoreactivity to proliferating cell nuclear antigen (PCNA), silver colloid staining for nucleolar organizing regions (AgNORs), and DNA flow cytometry were performed in 10 of the 13 cases. The proportion of PCNA-positive cells was less than 1% in all cases and the AgNORs score ranged from 1.11 to 2.0 (mean 1.67). The DNA flow cytometry revealed diploidy in all cases and the calculated proliferation index ranged from 5.1% to 9.6% (mean 7.8%). The one case of tumor recurrence, in which the authors performed the study of proliferative potential, and another case that demonstrated mild nuclear pleomorphism also showed low percentages of PCNA-positive cells, low AgNORs scores, and diploidy in DNA flow cytometry. It is suggested that most central neurocytomas follow a benign clinical course with low proliferative potential assessed by PCNA, AgNORs, and DNA flow cytometry; however, recurrence is possible within a relatively short time period.
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PMID:Central neurocytoma: proliferative potential and biological behavior. 901 Apr 44

Tumor progression and clinical outcome for patients with renal cell carcinomas (RCCs) cannot be predicted based solely on tumor staging and grading. In a retrospective study we have therefore attempted to analyze the capacity of proliferation markers to provide additional prognostic information. One hundred seven cases of RCC were investigated by immunohistochemical analysis using two different monoclonal antibodies: PC10, which recognizes a proliferating cell nuclear antigen (PCNA), and MIB-1, which identifies the Ki-67 antigen in formalin-fixed, paraffin-embedded material. PCNA frequency ranged from 0% to 71% (mean, 17%), and MIB-1 expression, from 0% to 43% (mean, 11%). PCNA scores correlated significantly with MIB-1 immunoreactivity. PCNA and MIB-1 immunoreactivity showed a significant correlation with tumor grade. A strong correlation was also observed for T-component of stage and MIB-1 scores, but no correlation was found between PCNA and T-component of stage. In univariate analysis, PCNA immunoreactivity and MIB-1 scores were significant predictors of survival. Multivariate analysis, using a Cox proportional hazard model, showed PCNA index, N-component of stage, and tumor grade to be independent predictors of tumor progression, which is not the case for MIB-1 index.
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PMID:Proliferating cell nuclear antigen and MIB-1. An alternative to classic prognostic indicators in renal cell carcinomas? 902 73

The SENCAR stock of mice has proved to be a useful model in dissecting out the multistage nature as well as the critical mechanisms involved in skin tumorigenesis. This outbred stock was selectively bred to be susceptible to initiation with 7,12-dimethylbenz[a]anthracene (DMBA) and promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA). In order to obtain mice more suitable for genetic analyses of tumor susceptibility and tissue transplantation studies, several inbred lines of mice were derived from the SENCAR stock. One of these lines, the SSIN mice, has a higher susceptibility to tumor promotion compared to the SENCAR stock but is very resistant to tumor progression. On the other hand, the SENCAR B/Pt mice, derived also from the outbred stock, not only have a tumor promotion susceptibility almost identical to the SSIN mice, but they also have a high susceptibility to tumor progression. In order to understand the nature of the phenotypic differences between these two inbred lines we have characterized them using several parameters and markers that are associated with the progression of papillomas to squamous cell carcinoma (SCC). In this sense we analysed the tumor multiplicity and SCC incidence, and the expression of markers of progression and cell cycle related proteins in papillomas derived from both strains. Our results showed that while both strains have a similar papilloma multiplicity and incidence the SENCAR B/Pt mice have 67% incidence of SCC, compared to 0% in the SSIN. SENCAR B/Pt papillomas at 30 weeks of promotion have a higher and aberrant expression of K13, and loss of connexin 26. TGF-beta1 was found to be over-expressed in the suprabasal and superficial cells in the SENCAR B/Pt papillomas, while it was only expressed in the superficial cell layer in those derived from SSIN. The SENCAR B/Pt papillomas also showed an enlarged proliferative compartment with overexpression of cyclin D1 and PCNA as seen by immunohistochemistry and Western blot.
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PMID:Analysis of two inbred strains of mice derived from the SENCAR stock with different susceptibility to skin tumor progression. 947 3


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