Since the PI3K pathway plays an r The transport of glucose and insulin-mediated metabolism is important for the inhibition of the PI3K signaling pathway in tumors using positron emission tomography scan using fluorodeoxyglucose measured D-glucose as a probe. A recent study has shown that the effect of BEZ235 to reduce the tumor vascular Permeability t by Cont Markets magnetic resonance imaging to monitor dynamic Nnte 116 k. These types of molecular imaging techniques offer a minimally invasive approach to the efficacy of PI3K inhibition determine targeted 117, and may optionally be predictive for clinical response. PIK-90 Sensitivity and resistance to targeted therapies PI3K One of the most important Ons of targeted therapies, the importance of adapting the treatment to the patient. Perhaps the best predictor of potential success of a kinase inhibitor has been the presence of an activating mutation or other Con Modifications of the genome of the target kinase.
Examples include the use of imatinib in patients with myeloid leukemia mie In chronic BCR ABL fusions, trastuzumab and lapatinib with HER2-positive breast tumors and gefitinib and erlotinib in patients with lung cancer, mutations and / or amplification of the EGFR. This logic l Sst suggest that PI3K inhibitors in tumors with activating mutations in p110 or loss of PTEN, w Expected during AKT mutations that sensitize tumors to inhibitors of AKT. It also seems likely that targeting a path just downstream Rts of genetic L Version will be effective. Thus, the PI3K and Akt inhibitors . After all, k Can inhibitors of mTOR kinase inhibitors and further down the track even for tumors with PI3K activation. It is not clear how the fa Distant one, a mutation of the nodes in the target path to be and remain sensitive to inhibition.
Since most tumors are genetically complex, it is likely that mutations in genes / United Change au PI3K he pr Planned sensitive tumor or, more probably, best Constantly PI3K against targeted therapy. An obvious source of resistance is a mutation or amplification of one component of the downstream channel. Since p110 mutations or loss of PTEN HER2-positive tumors, which make up trastuzumab 118, 119 k can, It is likely that more or k tumors with mutations in different downstream kinases Can the action of inhibitors block directed against its upstream component . It is therefore important that patients are likely to respond to specifically target cancer treatment PI3K and identify nonresponders select auszuw.
Remarkably, k These events can either prime R resistance or be acquired w During treatment. For example, say Gatekeeper mutations k Can occur after therapy targeted protein kinase. These mutations occur at a residue in the Kinasedom Ne of the target kinase and block the binding of the inhibitor of catalysis, w While allowing to proceed. Shokat and his colleagues identified a functional screen against a structurally vielf Ltigen group of PI3K inhibitors and m Possible hotspot resistance mutations p110, but surprisingly a lack of resistance mutations residues121 the doorman. Other known resistance mechanisms include the activation of alternative ways to gefitinib resistance induced reactivation HER3 signaling in lung cancer due to incomplete Ndiger inhibition of HER2 amplification or MET 122,124.