Background Dysregulated expression levels of different microRNAs are reported in both serum and inflamed joints of RA patients.
Objectives To determine whether administration of Tocalizumab (TCZ), a neutralizing anti-IL-6 receptor antibody, changes expression levels of selected miRNAs, which were previously described in the context of RA.
Methods 40 RA patients diagnosed with moderate to severe disease activity according to both DAS28 and CDAI scores, and were started on TCZ therapy, were enrolled in the study. Serum samples that were obtained before treatment and 4 months after TCZ treatment initiation, were analyzed for the relative expression of miR-16, -21, -132, -146a, -150, -155, -203, -221, and -323 by qPCR.
Results No significant changes in the expression levels of the tested miRNAs were found after TCZ treatment. However, when patients were stratified to responders and non-responders according to both the CDAI and DAS28 scores, the levels of miR-203 alone, out of the 9 miRNAs examined, were increased by 8.2% (p<0.0335) only in the responding group after 4 months of TCZ treatment, relative to the no-responders.
Conclusions The expression levels of miR-203 could serve as a potential biomarker that predicts a positive response to TCZ treatment in RA patients.
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Acknowledgements The first and second authors are equal contributors.
Disclosure of Interest None declared