NEUROECTODERMAL TUMORS EXPRESSING C-MYC, L-MYC, AND N-MYC IN TRANSGENIC MICE THAT CARRY THE E1A E1B GENE OF HUMAN ADENOVIRUS-TYPE-12/

Adenovirus early 1 (E1) region gene products, including E1A and E1B, a re required for transformation of primary cultured rodent cells. In or der to investigate in vivo action of the E1 region, we established a l ine of transgenic mice carrying the oncogenic E1A and E1B genes of hum an adenovirus type 12 under control of the human angiotensinogen promo ter. Histopathological analyses indicated that transgenic mice heritab ly develop neuroectodermal tumors arising from the pelvic region with varying degrees of incidence. The transgene was expressed in the neuro ectodermal tumors as well as in TNT-1 cells, a cell line established f rom the tumors, where the human angiotensinogen promoter was constitut ively active. The high level expression of c-, L-, and N-myc without g ene amplification was notable in the original tumors and TNT-1 cells, but not in another tissue examined. The co-expression of the three set s of myc family genes in both the original tumors and the established cell line provided the possibility that the target cells for transform ation may belong to a specific cell type that expresses all these onco genes during development.