In Vitro Transformation by the Adenovirus-Sv40 Hybrid Viruses

Abstract

Tumors induced with hamster kidney cells transformed by the adeno 2-, adeno 3-, adeno 7-, and adeno 12-SV40 hybrid viruses, and by adenovirus type 12, were examined histologically. The tumors induced with adeno 2-, adeno 3-, and adeno 7-SV40-transformed cells were similar to tumors induced with SV40-transformed hamster kidney cells but contained cells intermediate in morphology between SV40 and adenovirus tumor cells and occasionally contained nests of adenovirus-like cells. Cells transformed by the adeno 12-SV40 hybrid and by adenovirus type 12 gave rise to morphologically similar tumors. The results suggest that both viral genomes are operative in hybrid-transformed cells but that one genome is apparently responsible for the predominant morphology of the tumor. Evidence that the morphology of a single transformed target cell is determined by the transforming genome was discussed.

Transformation of hamster cells in vivo and in vitro by an adenovirus 4‐SV40 hybrid

“…The predominant cells in the tumors described here had pleomorphic vesicular nuclei with prominent nucleoli; these characteristics are typical of cells in SV40-induced tumors (Igel and Black, 1967). Small, fairly uniform cells, resembling those in adenovirus-induced tumors, were not found.…”

“…This type of cell had been found, however, in tumors induced by cells transformed by the Ad. 2-SV40 hybrid (Igel and Black, 1967). Also absent in the present tumors were the areas of undifferentiated carcinoma, adenocarcinoma, and epidermoid carcinoma found in tumors induced by hamster kidney cells transformed by SV40 (Rabson and Kirschstein, 1962).…”

“…Hamster tumors induced by inoculation of hamster kidney (HK) cells transformed by the Ad. 2-SV40 hybrid were similar in morphology to tumors induced with SV40-transformed HK cells, but also contained cells intermediate between SV40 and adenovirus tumor cells, and occasionally contained nests of adenovirus-like tumor cells (Igel and Black, 1967).The present studies were performed with a hybrid of adenovirus 4 (which is nononcogenic) and infectious SV40 (Easton and Hiatt, 1965;Easton and Hiatt, 1966). They show that both viral genomes are expressed in neoplastic hamster cells induced by this hybrid, but that tumor morphology is similar to that of neoplasms induced by inoculation of SV40.…”

“…Hamster tumors induced by inoculation of hamster kidney (HK) cells transformed by the Ad. 2-SV40 hybrid were similar in morphology to tumors induced with SV40transformed HK cells, but also contained cells intermediate between SV40 and adenovirus tumor cells, and occasionally contained nests of adenovirus-like tumor cells (Igel and Black, 1967).…”