Gene expression analysis in the lung of the rasH2 transgenic mouse at week 4 prior to induction of malignant tumor formation by urethane and N-methylolacrylamide.
These results demonstrate that TGF alpha, through EGFR overstimulation, can act synergistically with TPA to induce the formation, growth, and development of DMBA-initiated skin tumors containing classic Ha-ras gene mutations but not p53 gene inactivation.
In vitro DNA amplification followed by oligonucleotide mismatch hybridization was used to study the frequency of HRAS mutations in the benign self-regressing skin tumors keratoacanthomas and in squamous cell carcinomas.
DNAs were isolated from 35 pairs of skin tumors (25 BCCs and 10 SCCs) and matching normal skin from the same patients and analyzed for c-Ha-ras gene polymorphism by Southern blot hybridization.