ERRFI1 and neoplasm: The tumor suppressors genes such as EFNA1 (Ephrin-A1), ERRFI1 (ERBB Receptor Feedback Inhibitor 1), LATS2 (Large Tumor Suppressor Kinase 2) and PLK2 (Polo-Like Kinase 2) also show higher average expression in PD0325901 resistant cell lines and thus may be contributing to PD0325901 resistance (Supplementary Table S9).