As a biomarker predictive of response to the MEK inhibitor AZD6244 in breast cancer, we identified ENST00000346192, one of the longest isoforms of the insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) (Fig. 6e), which codes a protein with 556 amino acids. This evidence concerns the gene IGF2BP2 and breast cancer.