PD-166866

PD-166866 (CAS No.: 192705-79-6) is a synthetic small-molecule probe used in cell biology and early-stage drug discovery research, classified as a highly selective inhibitor of fibroblast growth factor receptor 1 (FGFR1) tyrosine kinase. It can inhibit receptor autophosphorylation and reduce downstream MAPK/ERK pathway activation, and is therefore used to dissect FGF-dependent signaling events such as proliferation, survival, migration, and angiogenesis, while helping to distinguish responses mediated by other receptor tyrosine kinases; in in vitro biochemical and cellular evaluations, it typically shows nanomolar inhibitory activity against FGFR1 (such as reported IC50 of approximately 52.4 nM and Ki of approximately 45.2 nM, with inhibition of autophosphorylation and MAPK phosphorylation in cells such as NIH3T3 and L6 occurring in the single-digit to low double-digit nanomolar range), whereas significant inhibition of non-target kinases such as PDGFR, EGFR, c-SRC, MEK, PKC, insulin receptor tyrosine kinase, and CDK4 often requires concentrations up to tens of micromolar, reflecting good target selectivity; in applications, it has been widely used in studies of cell growth and migration under FGF-stimulated conditions, supporting target validation and pathway mapping in models such as L6 myoblasts, NIH3T3 fibroblasts, and non-small cell lung cancer cell lines, and has also been used in ex vivo angiogenesis-related systems (for example, placental artery microvessel outgrowth assays) to evaluate the functional contribution of FGFR signaling and support FGFR-focused research hypothesis screening; the treatment duration, solvent conditions, and growth factor background used in experiments should be optimized according to the specific research objectives, and the working concentration typically covers the nanomolar to low micromolar range; this product is strictly limited to laboratory research use and is not intended for diagnostic, veterinary, or any human use.