Biomaterial Database

Inhibition of the tumor-initiating ability of the potent carcinogen 7,12-dimethylbenz(a)anthracene by the weak tumor initiator 1,2,3,4-dibenzanthracene. 1977

T J Slaga, and R K Boutwell

ARyl hydrocarbon hydroxylase (AHH) in mouse epidermis was inducible by topical application of several tumor-initiating polycylic aromatic hydrocarbons. The weak tumor initiator 1,2,3,4-dibenazanthracene (1,2,3,4-DBA), at dose level of 200 nmoles, increased AHH activity more than 10-fold over that of the acetone controls at 12 hr after treatment. Administration of the same quantity of the potent initiator 7,12-dimethylbenz(a)anthracene (DMBA) increased AHH activity approximately 4-fold over that of the control at 12 hr after treatment. Simultaneous treatment with 200 or 100 nmoles of DMBA and 1,2,3,4-DBA resulted in AHH activity that was 546 and 732% that of the controls, respectively, 12 hr after treatment: this was less AHH activity than was observed when 1,2,3,4-DBA was administered alone. Doses of 20 nmoles or more of 1,2,3,4-DBA, when given at about the same time as DMBA, effectively inhibited DMBA initiation of skin tumors in a two stage system of tumorigenesis. The results suggest that the weak initiator 1,2,3,4-DBA may program the epidermal AHH system to metabolize the strong carcinogen DMBA to noncarcinogenic intermediate(s).

UI	MeSH Term	Description	Entries
D009374	Neoplasms, Experimental	Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.	Experimental Neoplasms,Experimental Neoplasm,Neoplasm, Experimental
D010212	Papilloma	A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)	Papilloma, Squamous Cell,Papillomatosis,Papillomas,Papillomas, Squamous Cell,Papillomatoses,Squamous Cell Papilloma,Squamous Cell Papillomas
D002277	Carcinoma	A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm and not a synonym for "cancer."	Carcinoma, Anaplastic,Carcinoma, Spindle-Cell,Carcinoma, Undifferentiated,Carcinomatosis,Epithelial Neoplasms, Malignant,Epithelioma,Epithelial Tumors, Malignant,Malignant Epithelial Neoplasms,Neoplasms, Malignant Epithelial,Anaplastic Carcinoma,Anaplastic Carcinomas,Carcinoma, Spindle Cell,Carcinomas,Carcinomatoses,Epithelial Neoplasm, Malignant,Epithelial Tumor, Malignant,Epitheliomas,Malignant Epithelial Neoplasm,Malignant Epithelial Tumor,Malignant Epithelial Tumors,Neoplasm, Malignant Epithelial,Spindle-Cell Carcinoma,Spindle-Cell Carcinomas,Tumor, Malignant Epithelial,Undifferentiated Carcinoma,Undifferentiated Carcinomas
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001189	Aryl Hydrocarbon Hydroxylases	A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.	Microsomal Monooxygenases,Xenobiotic Monooxygenases,Hydroxylases, Aryl Hydrocarbon,Monooxygenases, Microsomal,Monooxygenases, Xenobiotic
D001551	Benz(a)Anthracenes	Four fused benzyl rings with three linear and one angular, that can be viewed as a benzyl-phenanthrenes. Compare with NAPHTHACENES which are four linear rings.	Benz(b)Phenanthrenes,Naphthanthracenes
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding