As shown in Fig. 1b, ERY974 induced tumour regression in PC10 and MKN74 xenografts (105 and 132% of tumour growth inhibition (TGI) activity, respectively), but not in NCI-H446 and MKN45 xenografts (50 and 37% of TGI activity, respectively), suggesting that factors apart from GPC3 expression are important for determining ERY974 potency. This evidence concerns the gene GPC3 and neoplasm.