PTPN11 and neoplasm: Moreover, in both cell lines, SHP2-D26 proved to be >30 times more potent than the parent inhibitor SHP099 in reducing the phosphorylation of ERK, thus impairing MAPK/ERK signaling pathway; it was also remarkably more potent than SHP099 in inhibiting tumor cell growth, with IC50 values ranging from 9.9 nM to 660 nM [61].