Table 1

Responsiveness of BK5.IGF-1 mice to two-stage carcinogenesisa

InitiationPromotion% of mice with papillomasPapillomas/mouse
Transgenic
Acetone (0.2 ml)TPA (5 nmol)721.00
DMBA (25 nmol)Acetone (0.2 ml)501.40
DMBA (25 nmol)TPA (5 nmol)10021.00
Nontransgenic
Acetone (0.2 ml)TPA (5 nmol)40.04
DMBA (25 nmol)Acetone (0.2 ml)00.00
DMBA (25 nmol)TPA (5 nmol)692.80
  • a Groups of 19–27 BK5.IGF-1 transgenic mice and age-matched nontransgenic littermates were initiated with 25 nmol DMBA or received acetone alone (0.2 ml). Two weeks after initiation, promoter treatments began with either 5 nmol TPA or acetone alone twice a week. Promotion was continued for 30 weeks.