AB0099 METHOTREXATE REDUCES THE INVASIVE ACTIVITIES OF PRIMARY RA SYNOVIAL FIBROBLASTS. (2nd June 2020)

• Record Type: Journal Article
• Authors: Ng, C. R.; Sheridan, K.; Cowley, S.; Dorris, E.; Veale, D.; Fearon, U.; Wilson, A. G.
• Is Part Of: Annals of the rheumatic diseases. Volume 79(2020)Supplement 1
• Page Start: 1349
• Page End: 1349
• Publication Date: 2020-06-02
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2020-eular.5477
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Rheumatoid Arthritis synovial fibroblasts (RASFs) are key player in tissue destruction via the production of a wide range of chemical reactions in the joint with high growth rate and resistance to mortality [1]. Methotrexate (MTX) is a dihydrofolate reductase inhibitor that attenuates inflammation within joints resulting in reduced cartilage and bone damage and is the anchor therapy for RA. Its mechanisms of action are thought to differ from its anti-proliferative effects and are known to include increased adenosine release (2), but may also involve alterations in intracellular methyl donor status resulting in alteration in DNA methylation and gene expression. Objectives: To investigate the effects of MTX on RASFs auto-aggressive activities, including invasion, migration, proliferation and apoptosis. Methods: RASF were derived from knee biopsies of RA patients taken at arthroscopy (n=9). Matrigel chambers were used to measure invasive activities. The cells were incubated with DMSO (control), 1μM or 10μM MTX for 96 hours. Wound healing (scratch assays) were used to measure migration. Proliferation and apoptosis was determined using BrdU and caspase-3/7 assays respectively. Significance was determined via repeated measures ANOVA using SPSS software. Results: Incubation with MTX resulted in significantly reduced invasive activity compared with DMSO control; 1μM (35%, p=0.006) and 10μM (58%, p=0.002) in paired samples. However MTX did not have significant effects on RASF migration, apoptosis or proliferation at either concentration. Conclusion: Our data reveals that MTX reduces the invasive potential of RASFs in vitro, this effect may contribute to the clinical efficacy of this agent. Further investigation will involve epigenome-wide methylation to determine if the DNA methylome of RASFs is altered by MTX. References: [1]Huber LC, et al. (2006) Rheumatol. 45(6):669-675. [2]Chan ES & Cronstein BN (2010) Nat Rev Rheumatol 6(3):175-178. Acknowledgments: This abstract arose from work funded by the National Children's Research Centre, Our Lady's Children's Hospital, Crumlin Disclosure of Interests: None declared