[Description]:
Alpelisib (BYL-719) is a potent and selective PI3Kα inhibitor with an IC50 of 5 nM.
[Related Catalog]:
[Target]
p110α:5 nM (IC50)
p110γ:250 nM (IC50)
p110δ:290 nM (IC50)
p110β:1200 nM (IC50)
[In Vitro]
Alpelisib (NVP-BYL719) potently inhibits the 2 most common PIK3CA somatic mutations (H1047R, E545K; IC50~4 nM). Alpelisib (NVP-BYL719) potently inhibits Akt phosphorylation in cells transformed with PI3Kα (IC50=74±15 nM) and shows significant reduced inhibitory activity in PI3Kβ or PI3Kδ isoforms transformed cells (≥15-fold compared with PI3Kα)[2]. Alpelisib (NVP-BYL719) decreases cell proliferation by blocking cell cycle in G0/G1 phase with no outstanding effects on apoptosis cell death in HOS and MOS-J tumor cells. BYL-719 inhibits cell migration and can thus be considered as a cytostatic drug for osteosarcoma. In murine preclinical models of osteosarcoma, Alpelisib (NVP-BYL719) significantly decreases tumor progression and tumor ectopic bone formation as shown by a decrease of Ki67+ cells and tumor vascularization. Alpelisib (NVP-BYL719) rapidly inhibits the levels of P-AKT and P-mTOR in all cell lines assessed, confirming the functional activity of Alpelisib (NVP-BYL719) on osteosarcoma cells. After 72 hr of treatment, Alpelisib (NVP-BYL719) significantly inhibits the cell growth of all osteosarcoma cell lines tested in a dose-dependent manner with an IC50 ranging from 6 to 15 µM and with the IC90 from 24 to 42 µM at 72 hr[3].
[In Vivo]
Alpelisib (BYL-719) displays excellent oral bioavailability in rats, mice and dogs and does not show any significant inhibition of the CYP450 enzymes[1]. Alpelisib (BYL-719) inhibits tumor growth in pre-clinical murine models of osteosarcoma. C57Bl/6J with MOS-J tumors (n=6 per group) are randomized as controls (vehicle) or Alpelisib (BYL-719) (12.5 mg/kg or 50 mg/kg per day)[3].
[Cell Assay]
Two thousand tumor cells are seeded into 96-well plates and, the day after, the cells are treated with Alpelisib (BYL-719) (1-50 µM) for 72 hr. Cell growth/viability is determined using a colorimetric assay using sodium 3′[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro-)benzene sulfonic acid hydrate (XTT Reagent Assay Kit). Absorbance is read at 490 nm. Cell viability is also determined by trypan blue exclusion assay; viable and nonviable cells are counted manually after 24 and 48 hr of treatment[3].
[Animal admin]
Rats[2] Tumor xenografts are grown subcutaneously or orthotopically in nude mice or nude Rowett rats (Hsd: RH-Fox1rnu) by injection of 3×106 to 1×10 7 cells or implantation of tumor fragments of approximately 50 mg. Tumor-bearing animals mice are treated with either vehicle control, Alpelisib (NVP-BYL719), or NVP-BKM120 (p.o., every day) at the doses indicated. For efficacy studies, tumor-bearing animals are enrolled when subcutaneously implanted tumors reached about 200 mm3 and treated with Alpelisib (NVP-BYL719) at 50 mg/kg daily. The response is reported as percentage change in tumor volume at last day of treatment relative to day 0 (start of treatment). Mice[3] A 5-week-old male C57Bl/6J mice are anesthetized by inhalation of an isoflurane/air mixture (2%, 1 L/min) before intramuscular injection of 1×106 mouse MOS-J osteosarcoma cells in close proximity to the tibia, leading to a rapidly growing tumor in soft tissue with secondary contiguous bone invasion. Tumors appeare at the injection site 8 days later and lead to osteoblastic lesions reproducing the osteoblastic form of human osteosarcoma. Three groups (n=6 per group) of C57Bl/6J are assigned randomly to receive either placebo or Alpelisib (BYL719) (oral administration, 12.5-50 mg/kg daily). The preventive treatment starts 1 day after tumor cells inoculation. Four groups of 6 C57Bl/6J are assigned randomly to receive either placebo (oral administration of methylcellulose 0.5% and intraperitoneal injection of water), Alpelisib (BYL719) (oral administration of 50 mg/kg per day), ifosfamide (intraperitoneal injection of 30 mg/kg three times during the first week), or a combination of Alpelisib (BYL719) (50 mg/kg daily) and ifosfamide (30 mg/kg, three times during the first week).
[References]
[Related Small Molecules]