IGF1R and cancer: EGFR-IGF-1R heterodimerization has been reported in drug resistant cancers, for example in non-small cell lung cancer (NSCLC), heterodimerization of EGFR and IGF-1R was increased upon exposure to the EGFR tyrosine kinase inhibitor, erlotinib [39], but the consequence of dimerization has remained poorly understood.