AZD8055S1555

AZD8055 shows low activity (∼1,000-fold) against all PI3K isoforms (α, β, γ, δ) and other members of the PI3K-like kinase family (ATM and DNA-PK). AZD8055 inhibits the phosphorylation of mTORC1 (p70S6K and 4E-BP1) as well as phosphorylation of the mTORC2 (Akt) and downstream proteins. The rapamycin-resistant T37/46 phosphorylation sites on 4E-BP1 can be fully inhibited by AZD8055, resulting in significant inhibition of cap-dependent translation. AZD8055 potently inhibits proliferation in U87MG, A549 and H838 cells with IC50 of 53, 50 and 20 nM, respectively. AZD8055 also induces autophagy and increased LC3-II levels in H838 and A549 cells. ^[1] AZD8055 decreases AML blast cell proliferation and cell cycle progression, reduces the clonogenic growth of leukemic progenitors and induces caspase-dependent apoptosis in leukemic cells but not in normal immature CD34+ cells. ^[2] AZD8055 indicates inhibitory against the pediatric preclinical testing program (PPTP) cell lines with IC50 of 24.7 nM and induces significant differences in EFS distribution. ^[3]