Kaempferol

Chemicals utilized for molecular and cellular biology and buffer preparation were purchased from Sigma-Aldrich (St. Louis, MO, USA). Cell culture medium including Dulbecco’s Modified Eagle’s Medium (DMEM; Cat#: 10-013-CVR, Corning, New York, NY, USA), modified Eagle’s Medium (MEM; Cat#: 10-010-CVR, Corning), and supplements including penicillin and streptomycin (Cat#: 15140-122, Gibco, Waltham, MA, USA) were purchased from Life Science Technologies (Rockville, MD, USA). Antibodies for phospho-FGFR3 (Cat#: SC-33041), FGFR3 (Cat#: SC-13121), p-RSK2 T577 (Cat#: SC-16407, SC-377501), RSK2 (Cat#: SC-9986), and β-actin (Cat#: SC-69879) were purchased from Santa Cruz Biotechnology (Santa Cruz, CA, USA). Antibodies for phospho-RSK T359/S363 (Cat#: 9344), phospho-ERK1/2 (Cat#: 9106), ERK1/2 (Cat#: 9102), and Ki-67 (Cat#: 9027) were purchased from Cell Signaling Technology (Beverly, MA, USA) for the western blot analysis, immunohistochemistry, and immunocytofluorescence. Fetal bovine serum (Cat#: 26140-079, Gibco) was purchased from Life Science Technologies and heat inactivated before utilization. Human recombinant bFGF (Cat#: SRP4037, Sigma-Aldrich), dimethylsulfoxide (DMSO, Cat#: D8418, Sigma-Aldrich), and kaempferol (Cat#: ALX-385-005, Enzo, Farmingdale, NY, USA) were purchased from Sigma-Aldrich.

Nine chemicals known to be present in Ginkgo biloba were obtained from various suppliers: bilobalide (Fisher Scientific, Hampton, NH, United States), ginkgolide A (LKT Laboratories, St. Paul, MN, United States), ginkgolic acid C15:1, ginkgolide B, isorhamnetin, and quercetin (Cayman Chemical Co., Ann Arbor, MI, United States), ginkgotoxin and rutin (Sigma Aldrich, Saint-Louis, MO, United States), kaempferol (Enzo Life Sciences Inc., Farmingdale, NY, United States) (Supplementary Figure S2).