Involvement of Ca2+ in platelet‐derived growth factor‐induced expression of c‐myc oncogene in Swiss 3T3 fibroblasts

Abstract
Addition of platelet‐derived growth factor (PDGF) to quiescent cultures of Swiss 3T3 fibroblasts rapidly increased the cytoplasmic free Ca2+ concentrations and afterwards the c‐myc mRNA levels. The concentrations of PDGF needed for both reactions were roughly the same. Moreover, the Ca2+ ionophores, A23187 and ionomycin, mimicked the actions of PDGF and increased the c‐myc mRNA levels. These results suggest that Ca2+ may be involved in the regulation of PDGF‐induced expression of the c‐myc gene.