PIK-75

PIK-75 is a reversible DNA-PK and p110α-selective inhibitor, which inhibits DNA-PK, p110α and p110γ with IC₅₀s of 2, 5.8 and 76 nM, respectively. PIK-75 inhibits p110α >200-fold more potently than p110β (IC₅₀=1.3 μM)^[1][2]. PIK-75 induces apoptosis^[3]. IC50 & Target: IC50: 2 nM (DNA-PK), 5.8 nM (p110α), 76 nM (p110γ), 510 nM (p110δ), ~1 μM (PI3KC2β), ~1 μM (mTORC1), 1.3 μM (p110β), 2.3 μM (ATM), 2.6 μM (hsVPS34), ~10 μM (PI3KC2α), ~10 μM (mTORC2), ~50 μM (PI4KIIIβ), 21 μM (ATR)^[1] In Vitro: PIK-75 also inhibits p110δ, PI3KC2β, mTORC1, ATM, hsVPS34, PI3KC2α, mTORC2, ATR and PI4KIIIβ with IC₅₀s of 510 nM, ~1 μM, ~1 μM, 2.3 μM, 2.6 μM, ~10 μM, ~10 μM, 21 μM, ~50 μM, respectively^[1].
PIK-75 alone blocks Thr 308 phosphorylation in L6 myotubes and 3T3-L1 adipocytes with IC₅₀ values of 1.2 and 1.3 μM, respectively^[1].
PIK-75 (1-1000 nM; 5 min) blocks the phosphorylation of PKB induced by insulin on both Ser473and Thr308 in CHO-IR cells in a dose-dependent manner, with an IC₅₀ of 78 nM^[2].
PIK-75 (0.1-1000 nM; 48 hours) inhibits the proliferation and survival of pancreatic cancer cells through apoptotic cell death^[3].
PIK-75 (0.1-1000 nM) also reduces the colony formation of pancreatic cancer MIA PaCa-2 and AsPC-1 cells^[3]. In Vivo: PIK-75 (2 mg/kg) potentiates anticancer activity of Gemcitabine (20 mg/kg) in vivo. Gemcitabine (20 mg/kg) or PIK-75 (2 mg/kg) alone reduces the tumor growth to similar degree. Beneficial effect of PIK-75/Gemcitabine is evident as this combination markedly reduces the tumor growth in vivowithout affecting the body weights of mice^[3].