title: The combination of RAD001 and MK-2206 exerts synergistic cytotoxic effects against PTEN mutant gastric cancer cells: involvement of MAPK-dependent autophagic, but not apoptotic cell death pathway.
abstract: In the current study, we showed that the combination of mammalian target of rapamycin (mTOR) inhibitor RAD001 (everolimus) and Akt inhibitor MK-2206 exerted synergistic cytotoxic effects against low-phosphatase and tensin homolog (PTEN) gastric cancer cells (HGC-27 and SNU-601 lines). In HGC-27 cells, RAD001 and MK-2206 synergistically induced G1/S cell cycle arrest, growth inhibition, cell death but not apoptosis. RAD001 and MK-2206 synergistically induced light chain 3B (LC3B) and beclin-1 expression, two important autophagy indicators. Meanwhile, the autophagy inhibitor 3-methyladenine (3-MA) and chloroquine inhibited the cytotoxic effects by RAD001 and MK-2206, suggesting that autophagic, but not apoptotic cell death was important for the cytotoxic effects by the co-administration. We observed that the combination of RAD001 and MK-2206 exerted enhanced effects on Akt/mTOR inhibition, cyclin D1 down-regulation and ERK/MAPK(extracellular signal-regulated kinase/mitogen-activated protein kinases) activation. Intriguingly, MEK/ERK inhibitors PD98059 and U0126 suppressed RAD001 plus MK-2206-induced beclin-1 expression, autophagy induction and cytotoxicity in HGC-27 cells. In conclusion, these results suggested that the synergistic anti-gastric cancer cells ability by RAD001 and MK-2206 involves ERK-dependent autophagic cell death pathway.
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Ji
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Interventional Radiology, Suzhou Hospital Affiliated to Nanjing Medical University, Suzhou, Jiangsu, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Cheng
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Jinjia
authors.initials: J
authors.lastname: Chang
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Gastric Cancer and Soft Tissue Sarcomas, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Biqiang
authors.initials: B
authors.lastname: Zheng
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Rongliang
authors.initials: R
authors.lastname: Zheng
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Zuojun
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Chenchen
authors.initials: C
authors.lastname: Wang
authors.affiliation: Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China.
authors.forename: Zhiqing
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Rujiao
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai Medical College, Fudan University, Shanghai, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Li
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D001343:Autophagy / Q000187:drug effects*; D000071186:Beclin-1; D002070:Butadienes / Q000494:pharmacology; D045744:Cell Line, Tumor; D002738:Chloroquine / Q000494:pharmacology; D019938:Cyclin D1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D004357:Drug Synergism; D000068338:Everolimus; D005419:Flavonoids / Q000494:pharmacology; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015972:Gene Expression Regulation, Neoplastic; D006575:Heterocyclic Compounds, 3-Ring / Q000494:pharmacology*; D006801:Humans; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D051059:PTEN Phosphohydrolase / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000494:pharmacology; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; D002070:Butadienes; C530104:CCND1 protein, human; D005419:Flavonoids; D006575:Heterocyclic Compounds, 3-Ring; C502070:MAP1LC3B protein, human; C548887:MK 2206; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D009570:Nitriles; C113580:U 0126; D019938:Cyclin D1; C025946:3-methyladenine; D002738:Chloroquine; D000068338:Everolimus; C546842:MTOR protein, human; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases; D020928:Mitogen-Activated Protein Kinases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human; D000225:Adenine; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D020123:Sirolimus