The Differential Expression Research Of Circular RNA In Patients With Systemic Lupus Erythematosus

Objective:Using circ RNA microarray technology to explore the differential expression circular RNA（ circ RNA） in peripheral mononuclear cells（ PBMCs） in the systemic lupus erythematosus（ SLE） patients, which lay the foundation theory for the further studies on novel non-invasive biomarkers and the investigation of pathogenesis of SLE. Method:The participants in this research consist of SLE patients（n=10）、 rheumatoid art hritis（RA）patients（n=10）and normal controls（NC）（n=10）. Peripheral venous b lood from each participant was collected to separate the PBMCs,which the total RNA was extracted from the PBMCs. The purity and concentration of total RNA samples were determined with Nano Drop ND-1000.Then, the total RNA each sample was ampl ified and transcribed into fluorescent c RNA. The labeled c RNAs were hybridized onto the Human circ RNA Array（6x7K） and were scanned by the Axon Gene Pix 4000 B microarray scanner. Gene Pix Pro 6.0 software was used to analyze acquired array ima ges. Quantile normalization of raw data and subsequent data processing were performe d using the R software package. The circ RNAs that at least 2 out of 3 samples have flag "expressed"（greater than 2 times background standard deviation） were retained f or further differential analyses. Differentially expressed circ RNAs with statistical signifi cance were identified through Fold Change filtering. The circ RNA/mi RNA interaction was predicted with Arraystar’s home-made mi RNA target prediction software. All the d ifferentially expressed circ RNAs were annotated in detail with the circ RNA/mi RNA int eraction information. At last, we use real-time Quantitative polymerase chain reaction（R T-PCR） technology to verify the reliability of the experiment. Result:Compared with NC group,a total of 745 circ RNA were significantly differentially expressed, including 182 up-regulated and 563 down-regulaed. Compared with RA group, a total of 671 circ RNA were significantly differentially expressed, including 225 up-regulated and 446 down-regulated. Six up-regulated circ RNA :hsa_circ₀007337, hsa_c irc₀047891,hsa_circ₀001349,hsa_circ₀046555,hsa_circ₀046215,hsa_circ₀056536 and Five down-regulated circ RNA : hsa_circ₀005480,hsa_circ₀001854,hsa_circ₀070113,h sa_circ₀044468,hsa_circ₀006608 were validated by RT-PCR. The RT-PCR results and microarray data are consistent. Bioinformatics analysis shows that circ RNA may play an important role in the development of SLE through the circ RNA/mi RNA interaction. Conclusion:The circ RNA expression of PBMCs in SLE patients is specific. The circ RNA w hich significantly differentially and specifically expressed in SLE can be used as poten tial diagnostic biomarkers. Furthermore,these data suggest that the significantly differe ntially expressed circ RNA may contribute to SLE pathogenesis,which can be used to a mechanism of reference and supplement.