Effect of a Tumor Promotor on Amino Acid Transport in Mouse Fibroblasts

Abstract

Phorbol 12-myristate 13-acetate, a highly active tumor-promoting agent, accelerates the uptake of .alpha.-aminoisobutyric acid (AIB) in mouse fibroblasts. The increase in AIB uptake was caused by changes in the plasma membrane and was accompanied by a decrease in the Km value for AIB and an increase in Vmax. The increase in nutrient uptake may be an essential factor in the induction and maintenance of the malignant phenotype of these cells.