Biomaterial Database

Antitumor activity in skin of Skh and Sencar mice by two dietary beta-carotene formulations. 1990

L A Lambert, and W H Koch, and W G Wamer, and A Kornhauser

Division of Toxicology, US Food and Drug Administration, Washington, DC 20204.

There is currently a great interest in the protective potential of beta-carotene and other micronutrients against carcinogenesis. We investigated the role of beta-carotene in modifying 7,12-dimethylbenz[a]anthracene (DMBA)-initiated, 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted, two-stage skin carcinogenesis. We were interested in comparing the protective effects of two types of dietary beta-carotene, a beadlet formulation and crystalline beta-carotene, in two strains of mice (Skh:HR-1 and CR:ORL Sencar). Mice were maintained throughout the study on one of these 3% beta-carotene-fortified diets or on control diets. In Week 11 after the start of the diets, the DMBA/TPA treatment regimen was begun. The resulting skin tumors were counted weekly. In addition, serum and skin levels were monitored for beta-carotene at the time of chemical initiation and at the termination of the study. A decrease in the number of cumulative tumors in the beta-carotene-fed animals compared with the appropriate control groups was observed in both strains of mice. However, statistical evaluation of the data revealed that the decrease was significant only in Skh mice. This phenomenon might be explained by the inherent sensitivity of Sencar mice to the two-stage carcinogenesis treatment regimen. The mechanism of the protective effect found in this study is still not clear. Recent data suggest that a vitamin A pathway is not probable but that a direct 1O2 and/or radical-quenching property of the parent beta-carotene molecule may be involved. This study also demonstrates that two-stage-induced skin tumorigenesis can be modified by both types of beta-carotene-fortified diets.

UI	MeSH Term	Description	Entries
D008815	Mice, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.	Inbred Mouse Strains,Inbred Strain of Mice,Inbred Strain of Mouse,Inbred Strains of Mice,Mouse, Inbred Strain,Inbred Mouse Strain,Mouse Inbred Strain,Mouse Inbred Strains,Mouse Strain, Inbred,Mouse Strains, Inbred,Strain, Inbred Mouse,Strains, Inbred Mouse
D001835	Body Weight	The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.	Body Weights,Weight, Body,Weights, Body
D002338	Carotenoids	The general name for a group of fat-soluble pigments found in green, yellow, and leafy vegetables, and yellow fruits. They are aliphatic hydrocarbons containing 4 terpene subunits.	Carotenes,Carotenoid,Tetraterpene Derivatives,Tetraterpenes,Carotene,Derivatives, Tetraterpene
D004032	Diet	Regular course of eating and drinking adopted by a person or animal.	Diets
D005260	Female		Females
D005527	Food, Fortified	Any food that has been supplemented with essential NUTRIENTS either in quantities that are greater than those normally present, or which are not found in the food typically. Fortified food also includes food enriched by adding various nutrients to compensate for those removed by refinement or processing. (Modified from Segen, Dictionary of Modern Medicine, 1992).	Enriched Food,Food, Supplemented,Enriched Foods,Food, Enriched,Foods, Enriched,Foods, Fortified,Foods, Supplemented,Fortified Food,Fortified Foods,Supplemented Food,Supplemented Foods
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
D012867	Skin	The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
D012878	Skin Neoplasms	Tumors or cancer of the SKIN.	Cancer of Skin,Skin Cancer,Cancer of the Skin,Neoplasms, Skin,Cancer, Skin,Cancers, Skin,Neoplasm, Skin,Skin Cancers,Skin Neoplasm
D013755	Tetradecanoylphorbol Acetate	A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.	Phorbol Myristate Acetate,12-Myristoyl-13-acetylphorbol,12-O-Tetradecanoyl Phorbol 13-Acetate,Tetradecanoylphorbol Acetate, 4a alpha-Isomer,12 Myristoyl 13 acetylphorbol,12 O Tetradecanoyl Phorbol 13 Acetate,13-Acetate, 12-O-Tetradecanoyl Phorbol,Acetate, Phorbol Myristate,Acetate, Tetradecanoylphorbol,Myristate Acetate, Phorbol,Phorbol 13-Acetate, 12-O-Tetradecanoyl,Tetradecanoylphorbol Acetate, 4a alpha Isomer