Cellular protein differences between nontumorigenic Ad5 and tumorigenic Ad12 transformed mouse cells

Murine fibroblasts transformed by adenovirus 12 (Ad12) show reduced class I major histocompatibility complex (MHC) antigen synthesis and form tumors in syngeneic mice whereas those transformed by adenovirus 5 (Ad5) show no alteration in class I antigen synthesis and do not form tumors (K. B. Eager, J. Williams, D. Breiding, S. Pan, B. Knowles, E. Appella, and R. P. Ricciardi (1985) Proc. Natl. Acad. Sci. USA 82, 5525-5529). Nearly 1500 metabolically labeled polypeptides from the Ad5 and Ad12 transformed cell lines as well as polypeptides from a nontransformed murine line of the same haplotype were compared by two-dimensional gel electrophoresis. In addition to the reduction of the class I H-2 transplantation antigens seen in the Ad12-transformed lines, we detect few but reproducible polypeptide differences between the tumorigenic and nontumorigenic cell lines.