PDGF isoforms trigger different receptor dimerization and phosphorylation by binding to the corresponding PDGFRs, thus activating multiple downstream growth signaling pathways, such as PI3K, MAPK, and JAK/STAT pathways, to promote cancer cell proliferation, migration and invasion, angiogenesis, and drug resistance.443,446,447. The gene discussed is PIK3CA; the disease is cancer.