title: Mitomycin C induces apoptosis in rheumatoid arthritis fibroblast-like synoviocytes via a mitochondrial-mediated pathway.
abstract: OBJECTIVE
  Rheumatoid arthritis (RA) is a systemic chronic inflammatory disease characterised by prominent synoviocyte hyperplasia and a potential imbalance between the growth and death of fibroblast-like synoviocytes (FLS). Mitomycin C (MMC) has previously been demonstrated to inhibit fibroblast proliferation and to induce fibroblast apoptosis. However, the effects of MMC on the proliferation and apoptosis of human RA FLS and the potential mechanisms underlying its effects remain unknown.
  
  
  METHODS
  Cell viability was determined using the Cell Counting Kit-8 assay. Apoptotic cell death was analysed via Annexin V-FITC/PI double staining and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling. The production of intracellular reactive oxygen species (ROS) was assessed via flow cytometry, and the changes in mitochondrial membrane potential (ΔΨm) were visualized based on JC-1 staining via fluorescence microscopy. The expression of apoptosis-related proteins was determined via Western blot.
  
  
  RESULTS
  Treatment with MMC significantly reduced cell viability and induced apoptosis in RA FLS. Furthermore, MMC exposure was found to stimulate the production of ROS and to disrupt the ΔΨm compared to the control treatment. Moreover, MMC increased the release of mitochondrial cytochrome c, the ratio of Bax/Bcl-2, the activation of caspase-9 and caspase-3, and the subsequent cleavage of poly(ADP-ribose) polymerase.
  
  
  CONCLUSIONS
  Our findings suggest that MMC inhibits cell proliferation and induces apoptosis in RA FLS, and the mechanism underlying this MMC-induced apoptosis may involve a mitochondrial signalling pathway.
authors.affiliation: Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Chuqi
authors.initials: C
authors.lastname: Yan
authors.forename: Dechao
authors.initials: D
authors.lastname: Kong
authors.forename: Dong
authors.initials: D
authors.lastname: Ge
authors.forename: Yanming
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xishan
authors.initials: X
authors.lastname: Zhang
authors.forename: Changhui
authors.initials: C
authors.lastname: Su
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Cao
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D002452:Cell Count; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D024101:Mitochondrial Proteins / Q000096:biosynthesis; D016685:Mitomycin / Q000008:administration & dosage*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013582:Synovial Fluid / Q000187:drug effects / Q000378:metabolism
chemical_list: D024101:Mitochondrial Proteins; D017382:Reactive Oxygen Species; D016685:Mitomycin