Conditional expression of the transformed phenotype in an

Abstract

A subclone of ts 14/MNU/2, derived from a heteroploid (epithelial) monkey kidney cell line of BSC-1 and transformed in vitro by methylnitrosourea, expressed the transformed phenotype only at the elevated temperature of 39.5(0)C. Compared to the growth characteristics at 33(0)C, the transformed property was exhibited in the (1) high efficiency of plating at low cell densities, (2) colony morphology, (3) growth in absence of serum and (4) alterations in the quality and the quantity of chromosomal proteins in presence of low concentrations of serum. Such experimental systems may provide an effective control for studying molecular mechanisms related to transformation and neoplasia.