FASN and cancer: 80 Furthermore, an important feature of HER2-positive tumours that contributes to their aggressiveness is sustained upregulation of de novo lipogenesis.81 Indeed, overexpression of HER2 in non-transformed epithelial cells induces a lipogenic phenotype dependent on FASN activation that is reminiscent of cancer cells, whilst inhibition of HER2 or de novo lipogenesis ablates oncogenic activity and induces apoptosis.82 This suggests that oncogenic signalling downstream of HER2 may activate several complementary pathways that converge on increased lipogenesis.