title: Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2.
abstract: Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer.
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
authors.forename: Wen
authors.initials: W
authors.lastname: Yue
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.|Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Xi
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.|Department of Biostatistics, School of Public Health, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.|Department of Biostatistics, School of Public Health, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Chung S
authors.initials: CS
authors.lastname: Yang
authors.affiliation: Department of Oncology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P. R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
authors.forename: Darren
authors.initials: D
authors.lastname: Carpizo
authors.affiliation: Department of Oncology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, P. R. China.|Allan H. Conney Laboratory for Anticancer Research, Guangdong University of Technology, Guangzhou, P. R. China.
authors.forename: Huarong
authors.initials: H
authors.lastname: Huang
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.
authors.forename: Robert S
authors.initials: RS
authors.lastname: DiPaola
authors.affiliation: Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA.|Department of Epidemiology, School of Public Health, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
authors.forename: Xiang-Lin
authors.initials: XL
authors.lastname: Tan
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001241:Aspirin / Q000008:administration & dosage*; D000072224:Bcl-2-Like Protein 11; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D019938:Cyclin D1 / Q000378:metabolism; D005260:Female; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008687:Metformin / Q000008:administration & dosage*; D051379:Mice; D016513:Mice, SCID; D064549:Myeloid Cell Leukemia Sequence 1 Protein / Q000378:metabolism*; D009368:Neoplasm Transplantation; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D014945:Wound Healing
chemical_list: D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; C438378:BBC3 protein, human; C000595707:BCL2 protein, human; C000606775:BCL2L11 protein, human; D000072224:Bcl-2-Like Protein 11; C000606776:Bcl2l11 protein, mouse; C579095:MCL1 protein, human; D008565:Membrane Proteins; D064549:Myeloid Cell Leukemia Sequence 1 Protein; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D019938:Cyclin D1; D008687:Metformin; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases; D053148:Caspase 3; D001241:Aspirin
keywords: Bcl-2 family member; apoptosis; aspirin; metformin; pancreatic cancer