PDGF autocrine signalling characterised by the coexpression of PDGF and PDGFR contributes to the development of a variety of tumours including malignant gliomas as a major signal pathway (Maxwell et al, 1990; Antoniades et al, 1992; Hermanson et al, 1992; Smits et al, 1992; Vassbotn et al, 1993; Guha et al, 1995). The gene discussed is PDGFRB; the disease is neoplasm.