Animal models of ovarian cancer are crucial for understanding the pathogenesis of the disease and for testing new treatment strategies. A model of ovarian carcinogenesis in the rat was modified and improved to yield ovarian preneoplastic and neoplastic lesions that pathogenetically resemble human ovarian cancer. A significantly lower dose (2 to 5 mug per ovary) of 7,12-dimethylbenz(a)anthracene...

We have previously reported that 7,12-dimethylbenz(a)an thracene (DMBA), given i.v. 24 hr after partial hepatectomy when DNA replication is maximal, binds tightly to DNA, inhibits its synthesis, and induces neoplastic changes in regenerating rat liver. We now report that DMBA injected i.v. 5 hr after partial hepatectomy (i.e., during the early prereplicative phase) inhibits DNA synthesis for at...

We investigated the effect of the chemopreventive compound diosmin and its aglycone form, diosmetin, on the carcinogen activation pathway mediated by the aryl hydrocarbon receptor (AhR) in MCF-7 human breast epithelial cancer cells. Treatment of the cells with diosmin caused a dose-dependent increase in the metabolism of the mammary carcinogen 7,12-dimethylbenz(a)anthracene (DMBA), as assessed ...

In a modified two-stage carcinogenesis experiment, the effectiveness of the initiator 7,12-dimethylbenz(a)anthracene (DMBA) and the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) in the epithelium of the forestomach of the mouse has been investigated. Fifty mice were treated intragastrically with a single dose of DMBA (50 mg/kg body weight), followed by repeated intrag...

We investigated the effect of the chemopreventive compound diosmin and its aglycone form, diosmetin, on the carcinogen activation pathway mediated by the aryl hydrocarbon receptor (AhR) in MCF-7 human breast epithelial cancer cells. Treatment of the cells with diosmin caused a dose-dependent increase in the metabolism of the mammary carcinogen 7,12-dimethylbenz(a)anthracene (DMBA), as assessed ...

In an attempt to obtain a source of material for chemi cal studies, the binding of 7,1 2-dimethylbenz(a)anthracene (DMBA) was studied in E. coli, B. subtilis, and ascites tumor cells. For the bacteria a dose-dependent binding was found, but the level of binding was low. In the case of the ascites tumor cells in the mouse, binding of DMBA to DNA, RNA, and protein showed a dependence on time afte...

BACKGROUND Afobazole, a new 2-mercapto-benzimidazole derivative, exhibited antimutagenic activity in chromosome aberration tests and antioxidant properties. The aim of this study was to demonstrate the potential chemopreventive effect of afobazole on the level of early biological effects by analysing changes in oncogene and tumor suppressor gene expression. MATERIALS AND METHODS Single intrap...

The present study has investigated the modulating effect of carnosic acid on the expression pattern of cell proliferative (proliferating cell nuclear antigen (PCNA) cyclin D1 and a transcription factor c-fos), apoptotic (p53, Bcl-2, Bax caspase -3 and 9), inflammatory (Nuclear factor kappa B (NFκB) and cyclooxygenase-2 (COX- 2) and angiogenic (vascular endothelial growth factor (VEGF) markers d...

OBJECTIVE [corrected] The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster's buccal pouch chemical carcinogenesis model. STUDY DESIGN Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumo...

The modulating effect of curcumin and ferulic acid was investigated on expression pattern of apoptosis regulatory p53 and bcl-2 proteins in oral squamous cell carcinoma (OSCC). The OSCC was induced in the buccal pouch of golden Syrian hamster by painting with 0.5% 7,12-dimethylbenz[a]anthracene (DMBA) three-times a week for 14 weeks. The expression pattern of p53 and bcl-2 proteins was analyzed...