FRS2 and neoplasm: Additionally, in FGFR-altered cell lines, FGFR, FGFR substrate 2 (FRS2), phospholipase C γ1 (PLCγ1), and ERK1/2 phosphorylation levels are consistently reduced by deficient nanomolar erdafitinib concentrations, which results in the inhibition of proliferation of various FGFR-positive tumor cell lines [27].