In GBM, ERBB3, IGFR1R and TGFBR2 were positively correlated with PDGFR, and combining a PDGFR inhibitor with either an ERBB3 inhibitor or an IGF1R inhibitor resulted in a more significant reduction in tumour growth than each inhibitor alone [69]. Here, TGFBR2 is linked to glioblastoma.