We measured the relative binding of the labeled carcinogen 9,10-dimethyl-l,2-benzanthracene-3H (DMBA-3H) to mouse satellite and main-band epidermal DNA 24 hr after the topical application of the carcinogen to mouse skin. Labeled DMBA-bound DNA was fractionated into satellite and main-band components by composite gel electrophoresis and by isopycnic CsCl centrifugation. With both fractionation m...

We measured the relative binding of the labeled carcinogen 9,10-dimethyl-l,2-benzanthracene-3H (DMBA-3H) to mouse satellite and main-band epidermal DNA 24 hr after the topical application of the carcinogen to mouse skin. Labeled DMBA-bound DNA was fractionated into satellite and main-band components by composite gel electrophoresis and by isopycnic CsCl centrifugation. With both fractionation m...

Fifty young adult male and female albino rats were studied for the effect of systemically administered Cyclophosphamide upon chemical carcinogenesis of the submandibular gland. In 1 group of animals, pellets of 9,10-dimethyl-l,2-benzanthracene (DMBA) were implanted into the right submandibular glands. A 2nd group of animals received biweekly i.p. injections of Cyclophosphamide (Cytoxan) in addi...

Ninety male Syrian hamsters, 3 months of age, were divided into 6 equal experimental groups of 15 animals. Two groups served as controls for 8and 16-week experimental periods. In the remaining 4 groups, the light buccal pouch was painted 3 times weekly with 9,10-dimethyl-l ,2-benzanthracene (DMBA) and sacrificed at 8 and 16 weeks. One 8-week and one 16-week experimental group were also injected...

It has been demonstrated previously that the exposure to 7,12-dimethyl[a]benzanthracene (DMBA) and UVB radiation leads to the development of epidermal cysts, squamous cell carcinomas (SCC), melanocytic hyperplasia and melanoma in human foreskins from newborns grafted to immunodeficient mice. Improved techniques in grafting full-thickness skin from adults have enabled us to study photocarcinogen...

The effects of the relatively weak carcinogen, 1,2-benzanthracene (BA), and its potent carcinogenic derivative, 7,12dimethylbenz(a)anthracene (DMBA), on the resumption of DNA synthesis in Syrian hamster embryo cells blocked in the S phase of the mitotic cycle, were analyzed. A maximum level of binding of BA to DNA (1.08 molecule/200,000 nucleotide units) occurred after 4 hours of treatment of c...

Ninety 3-month-old male and female albino rats were divided into 6 equal groups. Three groups of animals received daily i.p. injections (20 mg) of isoproterenol for a 2-week period. Pellets of powdered 9,10-dimethyl-l ,2-benzanthracene (DMBA) were implanted into the right submaxillary salivary glands of the ex perimental animals 2 weeks prior to, simultaneous with, and 2 weeks after commencemen...

Studies in Cucinogenesis. V. Methyl Derivatives of 1 : 2-Benzanthracene, M. J. SHEAR. In a further contribution to his series of studies on carcinogenesis Shear records his experiments with the methyl derivatives of 1 : 2-benzanthracene and related compounds. Of 21 compounds examined 10 produced tumors in mice a t the injection site. The more potent carcinogenic compounds were 5 : 10-dimethyl-1...

Pten heterozygous (Pten+/-) mice develop increased papilloma numbers and show decreased carcinoma latency time in comparison with controls after skin treatment with dimethyl benzanthracene (DMBA) and tetradecanoyl-phorbol acetate (TPA). H-ras mutation is normally a hallmark of DMBA-TPA-induced skin tumors, but 70% of carcinomas from Pten+/- mice do not exhibit this mutation, and in all cases ha...