Ch-Class I phosphatidylinositol 3-kinase enzymes and the class IV protein kinases mTOR and DNA-PK. All four compounds Panobinostat LBH-589 strongly inhibited p110 with IC 50 10 nmol / L. IP-103 was at least a size Enordnung better against p110. 620 PI 540 and PI have a relatively small force against the p110 γ with IC 50 300 nmol / L, w During GDC 0941 PI 103 and Kr Forces of 15 and 75 nmol / l introduced, and IP 103 and IP 540 was effective against mTOR that GDC and 620 IP 0941 and IP-103 st was stronger than all the other disadvantages PK DNA. Each of the compounds showed a high level of Ma selectivity to t similar to Class I phosphatidylinositol 3-kinase, when profiled against a broad spectrum of 70 protein kinases.
Inhibition of cell proliferation in vitro 1C shows the GI50 values of the four cellular Ren compounds in a panel of human cancer cell lines including normal prostate, ovarian, glioblastoma, and carcinoma Epidemo evaluated Of oropharyngeal, umbilical vein endothelial cells with human after 96 hours of continuous exposure. The tumor cell lines have genetic abnormalities that can lead to activation of phosphatidylinositol 3-kinase. All compounds showed strong inhibition of growth in all cell lines examined, with an activity t in the submicromolar range. IP 540 and IP 620 were less effective than PI GDC 103 and 0941 in some cell lines, eg in IGROV 1 cells and human umbilical vein endothelium. However, in the oropharyngeal Detroit 562 cancer cells, the values were very GI50 Similar for all four compounds.
Target modulation after treatment with phosphatidylinositol 3 kinase inhibitors in vitro We have previously reported inhibitory effects of PI 103 of the phosphatidylinositol 3-kinase activity t in various human cancer cells. We used immunoblotting to the path inhibition of PI 540 and 620 for PI in U87MG glioblastoma cells and PC3 prostate cancer and also in lung adenocarcinoma A549 cells.4 additives Tzlich were 50% inhibition of translocation of the transcription factor forkhead was observed at 62 and 81 nmol / l forPI 540 and IP 620, respectively, based on the previously reported 30 nmol / l 103rd for IP As n To search results, we examined the effect of these inhibitors in U87MG cells against various phosphorylated protein biomarkers of phosphatidylinositol 3-kinase using a set of electrochemiluminescent immunoassays.
The assays included AKT phosphorylation at Thr308, Ser473 AKT, GSK3 Ser9, Thr421/Ser424 p70S6K and ribosomal protein S6 Ser235/Ser236. MTOR Given the efficacy of compounds against kinase, mTORC1 inhibitor rapamycin was also included for comparison. The results of FIG. 1E show much Similar to 2 and 8 hours for IC 50 values of PI 103, PI 540, PI-620, and the 0941 GDC examined against each of the biomarkers of the phosphatidylinositol 3-kinase activity t. The four phosphatidylinositol 3-kinase inhibitors were more effective against the phosphorylation of AKT on both sides with IC50 values in the range of 10 to 40 nmol / l reducing the power of 7 to 12-fold compared to the phosphorylation of proteins further downstream rts of the phosphatidylinositol 3-kinase. For example, was PI 540 10 times less effective in inhibiting the phosphorylation of GSK3 Ser9 compared with phosphorylation of AKT. Rapamycin treatment does not