Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03092583 |
Other study ID # |
P/2015/252 |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
February 15, 2017 |
Est. completion date |
October 7, 2020 |
Study information
Verified date |
January 2021 |
Source |
Centre Hospitalier Universitaire de Besancon |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The aim of this project is to quantify global DNA methylation in patients with Ankylosing
Spondylitis or Axial Spondyloarthritis as compared with control subjects.
Description:
Spondyloarthritis covers a group of diseases with common clinical, genetic and radiographic
characteristics. Ankylosing spondylitis (AS) is the most common of these, and is usually
diagnosed in the presence of bilateral sacroiliitis by conventional x-ray, according to the
modified New York criteria. Axial spondyloarthritis (Ax-SpA) mainly affects the axial
skeleton and progresses towards the formation of bone or bony structures around the
sacro-iliac joint and spine, leading to the gradual formation of a bony bridge from the
sacro-iliac joint and ligamentous ossifications to the spine. Early forms of the disease do
not present such modifications to the sacro-iliac joint and therefore, show no visible
sacroiliitis on conventional x-ray. Thus, it is possible to classify a patient aged <45 years
with inflammatory lower back pain as having Ax-SpA, irrespective of the presence of
sacroiliitis by x-ray. Indeed, inflammation of the sacro-iliac joint and spine occurs before
the process of ossification and inflammation, and can be detected by MRI. This led the
Assessment of SpondyloArthritis international Society (ASAS) group to propose candidate
classification criteria for Ax-SpA, notably adapted to early forms of the disease.
Accordingly, patients with Ax-SpA without radiographic sacroiliitis are considered to have
non-radiographic Ax-SpA. Classification criteria for peripheral SpA are also available.
The determinants of AS and SpA are complex, and involve both genetic and environmental
factors. In addition to these factors, several studies in recent years have also highlighted
the emerging role of epigenetics in the pathophysiology of inflammatory diseases.
The term epigenetics refers to heritable and reversible modifications in gene expression
without any change in the coding DNA sequence. This process may be involved in the
pathophysiology of different diseases and their clinical expression. Several different
epigenetic mechanisms may concur to modify gene functioning. Changes to the chromatin and to
DNA (without modification of the encoding sequence itself) have been shown to be important
for the control of gene expression through suppressive or permissive factors. Thus, DNA
methylation could play a role in auto-immune or inflammatory diseases by regulating gene
expression, particularly those coding for pro-inflammatory mediators such as certain
cytokines, thereby contributing to dysregulation of the immune system.
DNA methylation is regulated by the activity of DNA methyltransferase enzymes (DNMT). In
multicellular eukaryotic organisms, DNA methylation is associated with chromatin repression,
and thereby, inhibition of gene expression. DNA methylation can be evaluated across the whole
genome, but also at the level of a specific candidate gene, such as the gene encoding a
pro-inflammatory cytokine.
The level of DNA methylation has been evaluated in rheumatoid arthritis (RA) and in systemic
lupus erythematosus (SLE), and a "methylated-DNA" signature has been observed in these
auto-immune diseases. Currently, there is no available data regarding DNA methylation in AS
or SpA in general. In this study, the investigators aim to analyse the global DNA methylation
in patients with AS or Ax-SpA.