title: The novel dual PI3K/mTOR inhibitor GDC-0941 synergizes with the MEK             inhibitor U0126 in non-small cell lung cancer cells.
abstract: Lung cancer is a malignant disease with poor outcome, which has led to a search for new therapeutics. The PI3K/Akt/mTOR and Ras/raf/Erk pathways are key regulators of tumor growth and survival. In the present study, their roles were evaluated by MTT assay, flow cytometry and Western blotting in lung cancer cells. We found that a high efficacy of antitumor activity was shown with GDC-0941 treatment in two gefitinib-resistant non-small cell lung cancer (NSCLC) cell lines, A549 and H460. In addition, H460 cells with activating mutations of PIK3CA were relatively more sensitive to GDC-0941 than A549 cells with wild-type PIK3CA. Furthermore, GDC-0941 was highly efficacious in combination with U0126 in inducing cell growth inhibition, G0-G1 arrest and cell apoptosis. These antitumor activities of combined treatment may be attributed to the alterations of G0-G1 phase regulators, apoptosis-related proteins and eukaryotic translation initiation factor 4B (eIF4B), induced by concomitant blockade of the PI3K/Akt/mTOR and Ras/raf/Erk pathways. In conclusion, this study suggests that multi‑targeted intervention is the most effective treatment for tumors. Additionally, the blockade of PI3K, mTOR and Erk with GDC-0941 and MEK inhibitors shows promise for treating gefitinib-resistant NSCLC.
authors.affiliation: Medical School, Ningbo University, Zhejiang 315211, PR China.
authors.forename: Zu-Quan
authors.initials: ZQ
authors.lastname: Zou
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Zhang
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Jérôme
authors.initials: J
authors.lastname: Bellenger
authors.forename: Yin-Zhuo
authors.initials: YZ
authors.lastname: Shen
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis; D002070:Butadienes / Q000494:pharmacology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology; D045744:Cell Line, Tumor; D004357:Drug Synergism; D004789:Enzyme Activation; D059585:G1 Phase Cell Cycle Checkpoints; D006801:Humans; D007191:Indazoles / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000473:pathology; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects*; D013449:Sulfonamides / Q000494:pharmacology*; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D002070:Butadienes; D007191:Indazoles; D020928:Mitogen-Activated Protein Kinases; D009570:Nitriles; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D047428:Protein Kinase Inhibitors; D013449:Sulfonamides; D058570:TOR Serine-Threonine Kinases; C532162:2-(1H-indazol-4-yl)-6-(4-methanesulfonylpiperazin-1-ylmethyl)-4-morpholin-4-ylthieno(3,2-d)pyrimidine; C113580:U 0126; C546842:MTOR protein, human