Antagonist of fibroblast growth factor (FGF) pathways via inhibition of FGF-mediated phosphorylation of ERK1/2 (By similarity). Thereby acts as an antagonist of FGF-induced retinal lens fiber differentiation, may inhibit limb bud outgrowth and may negatively modulate respiratory organogenesis (By similarity). Inhibits TGFB- induced epithelial-to-mesenchymal transition in retinal lens epithelial cells (By similarity). Inhibits CBL/C-CBL-mediated EGFR ubiquitination (PubMed:17974561). {ECO:0000250|UniProtKB:Q9QXV8, ECO:0000269|PubMed:17974561}. This is the function of ENSG00000136158 (SPRY2, sprouty RTK signaling antagonist 2).