- Coexpression of platelet-derived growth factor (PDGF) and PDGF-receptor genes by primary human astrocytomas may contribute to their development and maintenance. Maxwell, M., Naber, S.P., Wolfe, H.J., Galanopoulos, T., Hedley-Whyte, E.T., Black, P.M., Antoniades, H.N. J. Clin. Invest. (1990)