title: Enhanced sensitivity of tumorigenic cells to rapid rounding induced by phenylalaninol.
abstract: This study describes a rounding reaction induced in mammalian cells by the addition of phenylalaninol. In the Chinese hamster ovary tsH1 line the rounding occurred rapidly with a half time of 1 min at 25 mM phenylalaninol. After the removal of phenylalaninol, the rounding was reversed, leading to the reflattening of the cells with a half-time of 3.5 min. Rounding was inhibited by dibutyryl-cAMP and testosterone, and reflattening by cytochalasin B. Either in the case of the tsH1 line and its growth-control revertant GRC+L-73, or in the case of SV40-transformed and untransformed human WI-38 cells, the transformed cells displayed a weakened resistance toward rounding. Likewise rat cells transformed by th highly oncogenic adenovirus-12 were more sensitive to rounding than cells transformed by the poorly oncogenic adenovirus-5, which in turn were more sensitive than untransformed cells. However, drug-resistant cell-surface mutants of the Chinese hamster ovary GAT- line also exhibited an altered sensitivity to rounding. These findings suggest that more than one cellular component determines cellular sensitivity to phenylalaninol-induced rounding. One of these components is specifically altered, giving rise to an enhanced sensitivity, in the course of tumorigenic transformation.
mesh_terms: D000256:Adenoviridae; D000818:Animals; D002472:Cell Transformation, Viral / Q000187:drug effects; D002478:Cells, Cultured; D006224:Cricetinae; D003412:Cricetulus / Q000235:genetics; D003571:Cytochalasin B / Q000494:pharmacology; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D007668:Kidney / Q000166:cytology*; D051379:Mice; D008854:Microscopy, Electron; D009154:Mutation; D010053:Ovary / Q000166:cytology*; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D013539:Simian virus 40
chemical_list: C012481:phenylalaninol; D003571:Cytochalasin B; D010649:Phenylalanine