In vitro neoplastic transformation of newborn hamster salivary-gland tissue by oncogenic DNA viruses

Explant cultures of newborn hamster salivary-glands were infected with 4 oncogenic DNA viruses: polyoma virus, human adenovirus 12, simian virus 40 (SV40) and the LLE46 strain of adenovirus 7 (the adenovirus 7-SV40 “hybrid”). Only SV40 and LLE46 infected tissues underwent “transformation.” Subcutaneous injection of SV40 transformed cells into irradiated adult hamsters produced fibrosarcomas. Subcutaneous injection of LLE46 transformed cells, however, produced tumors which were bimorphic with 2 distinct histological elements, one composed of small hyperchromatic undifferentiated cells resembling an adenovirus type tumor and the other resembling an SV40-induced sarcoma. No evidence of salivary-gland function as indicated by amylase production could be demonstrated in the transformed cultures or in the tumors which they produced.