Comparative tumorigenicity of nitrochrysene isomers in newborn mice.
6-Nitrochrysene (6-NC) is a potent lung and liver carcinogen in the newborn mouse assay. In this report, we extended our studies of the structure--tumorigenicity relationships of the mononitrochrysene isomers. We synthesized 1-NC, 2-NC and 3-NC by oxidation of the corresponding aminochrysenes with mCPBA; efforts to synthesize 4-NC and 5-NC from 4- and 5-aminochrysene were not successful. The tumorigenic activities of 1-NC, 2-NC, 3-NC and 6-NC were compared. Groups of mice were treated with the appropriate compounds in dimethylsulfoxide (DMSO) by i.p. injection on the 1st, 8th and 15th day of life. At a total dose of 100 nmol/mouse, 6-NC induced significant incidences and multiplicities of lung tumors in mice in both sexes; only males were susceptible to liver tumor induction. At 100 nmol/mouse, induction of lung and liver tumors by 1-NC, 2-NC and 3-NC was not significantly different from that observed in mice treated with DMSO. The results indicate that nitro substitution at the 6-position of chrysene is critical for strong tumorigenicity in the newborn mouse assay.
el-Bayoumy
K
K
Division of Chemical Carcinogenesis, American Health Foundation, Valhalla, NY 10595.
Desai
D
D
Upadhyaya
P
P
Amin
S
S
Hecht
S S
SS
D000818:Animals; D000831:Animals, Newborn; D002273:Carcinogens / Q000633:toxicity*; D002911:Chrysenes / Q000633:toxicity*; D005260:Female; D007536:Isomerism; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced; D008175:Lung Neoplasms / Q000139:chemically induced; D008297:Male; D051379:Mice; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley
D002273:Carcinogens; D002911:Chrysenes; C035986:6-nitrochrysene