title: Distinctive regulation and function of PI 3K/Akt and MAPKs in doxorubicin-induced apoptosis of human lung adenocarcinoma cells.
abstract: Regulation and function of PI 3K/Akt and mitogen-activated protein kinases (MAPKs) in doxorubicin-induced cell death were investigated in human lung adenocarcinoma cells. Doxorubicin induced dose-dependent apoptosis of human lung adenocarcinoma NCI-H522 cells. Prior to cell death, both Akt and the MAPK family members (MAPKs: ERK1/2, JNK, and p38) were activated in response to the drug treatment. The kinetics of the inductions for Akt and MAPKs are, however, distinct. The activation of Akt was rapid and transient, activated within 30 min of drug addition, then declined after 3 h, whereas the activations of three MAPKs occurred later, 4 h after addition of the drug and sustained until cell death occurred. Inhibition of PI 3K/Akt activation had no effect on MAPKs' activation, suggesting that the two pathways are independently activated in response to the drug treatment. Inhibition of PI 3K/Akt and p38 accelerated and enhanced doxorubicin-induced cell death. On the contrary, inhibition of ERK1/2 or JNK had no apparent effect on the cell death. Taken together, these results suggest that PI 3K/Akt and MAPKs signaling pathways are all activated, but with distinct mechanisms, in response to doxorubicin treatment. Activation of PI 3K/Akt and p38 modulates apoptotic signal pathways and inhibits doxorubicin-induced cell death. These responses of tumor cells to cancer drug treatment may contribute to their drug resistance. Understanding of the mechanism and function of the responses will be beneficial for the development of novel therapeutic approaches for improvement of drug efficacy and circumvention of drug resistance.
authors.affiliation: Pulmonary Center, Department of Medicine, Boston University Medical Center, Boston, Massachusetts 02118, USA.
authors.forename: Yanqiu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Han
authors.initials: H
authors.lastname: You
authors.forename: Yu
authors.initials: Y
authors.lastname: Yang
authors.forename: Lin
authors.initials: L
authors.lastname: Wei
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.forename: Libo
authors.initials: L
authors.lastname: Yao
authors.forename: Daiming
authors.initials: D
authors.lastname: Fan
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yu
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000473:pathology; D017304:Annexin A5 / Q000032:analysis / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002352:Carrier Proteins / Q000494:pharmacology; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D045744:Cell Line, Tumor / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002867:Chromones / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D007700:Kinetics; D008175:Lung Neoplasms / Q000201:enzymology / Q000473:pathology; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D009025:Morpholines / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000187:drug effects / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism* / Q000502:physiology; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000502:physiology; D051057:Proto-Oncogene Proteins c-akt; D011725:Pyridines / Q000494:pharmacology; D015398:Signal Transduction / Q000502:physiology; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D017304:Annexin A5; D002352:Carrier Proteins; D020169:Caspases; D002867:Chromones; D003513:Cycloheximide; D004317:Doxorubicin; D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D008565:Membrane Proteins; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D009025:Morpholines; D009363:Neoplasm Proteins; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D011725:Pyridines; D048051:p38 Mitogen-Activated Protein Kinases; C114422:CAMK2N2 protein, human; C407989:JTB protein, human; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C494918:AKT1 protein, human; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one