List of abbreviations
Ankylosing spondylitis AS
Non-coding RNAs ncRNAs
Circular RNAs circRNAs
MiRNA response elements MREs
Competing endogenous RNAs ceRNAs
Systemic lupus erythematosus SLE
Multiple sclerosis MS
Rheumatoid arthritis RA
Primary biliary cholangitis PBC
Osteoarthritis OA
CeRNAs ceRNAs
RNA-sequencing RNA-seq
Peripheral blood mononuclear cells PBMCs
Differentially expressed circRNAs DECs
American College of Rheumatology ACR
Erythrocyte sedimentation rate ESR
C-reactive protein CRP
Bath Ankylosing Spondylitis Disease Activity Index BASDAI
Quality control QC
Receiver operating characteristic ROC
Phosphate-buffered saline PBS
Fetal bovine serum FBS
Enzyme-linked immunosorbent assay ELISA
Horseradish peroxidase HRP
Indirect immunofluorescence IF
Standard deviation SD
Control CN
Area under the curve value AUC
Abstract
Objectives: Circular RNAs (circRNAs) play a diverse
range of roles in physiological settings, wherein they can undergo
translation, directly interact with RNA-binding proteins, or function by
sequestering miRNAs to suppress their functionality. To analyze the
function and roles of circRNAs in the peripheral blood mononuclear cells
(PBMCs) of ankylosing spondylitis (AS) patients.
Methods: The expression of AS-related circRNAs were
detected by high-throughput RNA-sequencing within the PBMCs of 5 AS
cases and healthy controls. After profiling circRNA expression in these
samples, differentially expressed circRNAs (DECs) were identified, and a
qPCR-based validation approach was used to confirm the differential
expression of six of these DECs in patient samples. Spearman’s
correlation tests and ROC curve analyses were further used to assess the
relationship between disease severity and the expression of DECs of
interest in AS patients, after which a putative circRNA-microRNAs
(miRNAs) interaction network was constructed leading to the detection of
six validated DECs with competing endogenous RNA (ceRNA) functionality.
Besides, cell experiments were also performed to investigate the
potential mechanism of key circRNA in AS.
Results: 10,441 circRNAs were identified in these 10
PBMC samples, with 131 total DECs including 89 and 42 that were up- and
down-regulated, respectively. In qPCR validation assays, patterns of
hsa_circ_0000702, hsa_circ_0006209, hsa_circ_0047920,
hsa_circ_0001543,
hsa_circ_0072697 and
hsa_circ_0005076 were confirmed to align well with RNA-seq results. In
addition, the expression levels of
hsa_circ_0006209,
hsa_circ_0047920, and hsa_circ_0072697 were detected to be
positively correlated with disease
severity. ROC curve analyses suggested that hsa_circ_0072697 may offer
value as a diagnostic biomarker for AS. Cell experiments indicated that
hsa_circ_0072697 could suppress the progression of AS by targeting
NF-κB pathway
Conclusions: The identification of six circRNAs with
putative ceRNA functionality in AS patients highlights potential
molecular mechanisms governing this debilitating disease. However,
further research will be necessary to formally confirm the roles of
these DECs and their target miRNAs in AS. Further, hsa_circ_0072697
has a good diagnostic value in AS patients, and it could suppress the
progression of AS by targeting NF-κB pathway.