C-H-ras-1 expression in 7,12-dimethyl benzanthracene-induced Balb/c mouse mammary hyperplasias and their tumors
Cardiff, R.D.; Gumerlock, P.H.; Soong, M.M.; Dandekar, S.; Barry, P.A.; Young, L.J.; Meyers, F.J.
Oncogene 3(2): 205-213
1988
ISSN/ISBN: 0950-9232 PMID: 2842717 Document Number: 315096
Dimethylbenzanthracene (DMBA)-induced mouse mammary tumors characteristically contain an activated c-H-ras-1 gene with an A .fwdarw. T transversion in the 61st codon which is expressed as a rapidly migrating p21 c-H-ras. The role of the activated c-H-ras-1 locus in the initiation of mammary neoplasia was analysed by studying seven transplantable, DMBA-induced Balb/c premalignant mammary hyperplasias. The DNAs from these hyperplasias had no evidence of activation of the c-H-ras-1 gene. One of the fifteen tumors arising from untreated hyperplastic outgrowths had a 61st codon mutation. In contrast, 67% of the tumors developing in DMBA-treated hyperplasias had the characteristic 61 codon mutation. All of the tumors with the characteristic mutation expressed the corresponding rapid p21 c-H-ras. These data suggest that although c-H-ras-1 activation may play an important role in neoplastic progression, it had no definable role in the intiation or the maintenance of the mammary hyperplasias studied here.