Tumor Initiation And Promotion
Mostrando 1-12 de 23 artigos, teses e dissertações.
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1. Eicosanoids and cancer
Eicosanoids are 20-carbon bioactive lipids derived from the metabolism of polyunsaturated fatty acids, which can modulate various biological processes including cell proliferation, adhesion and migration, angiogenesis, vascular permeability and inflammatory responses. In recent years, studies have shown the importance of eicosanoids in the control of physiol
Clinics. Publicado em: 09/08/2018
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2. Distribuição COM-Poisson na análise de dados de experimentos de quimioprevenção do câncer em animais
Experimentos que envolvem a indução química de substâncias cancerígenas em animais são comuns na área biológica. O interesse destes experimentos é, em geral, avaliar o efeito de uma substância quimiopreventiva na destruição das células danificadas. Neste tipo de estudo, duas variáveis de interesse são o número de tumores induzidos e seus temp
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/03/2012
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3. Studies on mechanism of action of anti-tumor-promoting agents: their specificity in two-stage promotion.
The effects of fluocinolone acetonide (FA), retinoic acid (RA), and tosylphenylalanine chloromethyl ketone (TPCK) on two-stage promotion after 7,12-dimethylbenz[a]-anthracene (DMBA) initiation in female Sencar mice were investigated. The two-stage promotion protocol was achieved by twice weekly applications of 2 microgram of 12-O-tetradecanoylphorbol 13-acet
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4. Studies on the mechanism of skin tumor promotion: Evidence for several stages in promotion
The effects of nonpromoting and weakly promoting diterpenes on skin tumor promotion by 12-O-tetradecanoylphorbol 13-acetate (TPA) were investigated. When phorbol and phorbol 12,13-diacetate (both nonpromoting) were given simultaneously with TPA after 7,12-dimethylbenz[a]-anthracene (DMBA) initiation in female mice, they had no effect on TPA promotion. Howeve
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5. On the emergence of multifocal cancers
Several tumors can exist as multiple lesions within a tissue. The lesions may either arise independently, or they may be monoclonal. The importance of multiple lesions for tumor staging, progression, and treatment is subject to debate. Here we use mathematical models to analyze the emergence of multiple, clonally related lesions within a single tissue. We re
BioMed Central.
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6. v-Ha-ras transgene abrogates the initiation step in mouse skin tumorigenesis: effects of phorbol esters and retinoic acid.
Experimental carcinogenesis has led to a concept that defines two discrete stages in the development of skin tumors: (i) initiation, which is accomplished by using a mutagen that presumably activates a protooncogene, and (ii) promotion, which is a reversible process brought about most commonly by repeated application of phorbol esters. We have created a tran
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7. Antitumor promotion by phenolic antioxidants: inhibition of AP-1 activity through induction of Fra expression.
Induction of phase 2 detoxification enzymes by phenolic antioxidants can account for prevention of tumor initiation but cannot explain why these compounds inhibit tumor promotion. Phase 2 genes are induced through an antioxidant response element (ARE). Although the ARE resembles an AP-1 binding site, we show that the major ARE binding and activating protein
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8. Mechanisms for pituitary tumorigenesis: the plastic pituitary
The anterior pituitary gland integrates the repertoire of hormonal signals controlling thyroid, adrenal, reproductive, and growth functions. The gland responds to complex central and peripheral signals by trophic hormone secretion and by undergoing reversible plastic changes in cell growth leading to hyperplasia, involution, or benign adenomas arising from f
American Society for Clinical Investigation.
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9. Disruption of Stat3 reveals a critical role in both the initiation and the promotion stages of epithelial carcinogenesis
Constitutive activation of signal transducer and activator of transcription 3 (Stat3) has been found in a wide spectrum of human malignancies. Here, we have assessed the effect of Stat3 deficiency on skin tumor development using the 2-stage chemical carcinogenesis model. The epidermis of Stat3-deficient mice showed a significantly reduced proliferative respo
American Society for Clinical Investigation.
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10. Suppression of mouse mammary tumor proviral DNA and protooncogene expression: association with nutritional regulation of mammary tumor development.
Chronic energy intake restriction (CEIR) reduces mouse mammary tumor virus (MMTV)-induced mammary tumors in C3H/Ou mice. Fewer than 10% of C3H/Ou mice developed mammary tumors during 88 wk of study when subjected to CEIR regardless of calorie source (fat vs. carbohydrate). By contrast, 100% of mice fed ad libitum diets relatively high in fat or carbohydrate
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11. Therapy of murine squamous cell carcinomas with 2-difluoromethylornithine
Targeted overexpression of an ornithine decarboxylase (ODC) transgene to mouse skin (the K6/ODC mouse) significantly enhances susceptibility to carcinogenesis. While in most strain backgrounds the predominant tumor type resulting from initiation-promotion protocols is benign squamous papilloma, K6/ODC mice on a FVB/N background develop malignant squamous cel
BioMed Central.
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12. Peptide analogues alter the progression of premalignant lesions, as measured by Photofrin fluorescence.
Somatostatin analogue RC-160 and bombesin/gastrin-releasing peptide antagonist RC-3095 were infused at 2 micrograms per day via miniosmotic pumps implanted s.c. in hamsters with premalignant disease to examine the effect of these peptides on cancer promotion and progression. These analogues have been shown to inhibit growth of certain tumors, especially thos