cells did not grow on fibroblast monolayers or in soft agar in vitro but did induce tumors in athymic nude mice ( 12 of 15 ) after the s.c. injection of tissue-cultured cells ( 2.5 x 10 ( 6 ) to 4.5 x 10 ( 7 ) cells/mouse ) .
C0016030
fibroblast
C0007634
cells