Arthritis & Rheumatism, Volume 63,
November 2011 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Chicago, Illinois November 4-9, 2011.
Renal Mir-150 As Potential Biomarker of Chronicity in Lupus Nephritis.
Zhou1, Hua, Hasni2, Sarfaraz A., Tandon1, Mayank, Alevizos1, Ilias, Austin3, Howard A., Balow3, James E., Illei1, Gabor G.
Histological variations of kidney injury in lupus nephritis are associated with different renal outcomes. Novel quantitative biomarkers which can mirror the degree of renal damage may be useful to help clinical decision making and assist in the choice of optimal therapy. microRNAs (miRs) are involved in many biologic processes and have shown promise as biomarkers in other settings. In this study we assessed the association of miR expression profiles with histologic features of chronicity of kidney biopsies from proliferative lupus nephritis patients.
MicroRNA expression profiles were analyzed on total RNA obtained from 18 formalin fixed paraffin embedded (FFPE) kidney biopsies from 8 patients by Affymetrix miR microarray. The expression of miR-150 was assessed by Taqman qRT-PCR on 10ng of total RNA in 16 of these samples and an additional 7 samples from 6 patients. miR150 levels are expressed as their relative expression (deltaCt) compared to U48 used as an endogenous control. Repeat biopsies from the same patient were done based on clinical indication, primarily for nephritis flares. The association between miR-150 and histological chronicity index (CI) was analyzed using the Prism 5 statistical software package.
miR-150 was the most differentially expressed miR on microarrays between the renal biopsies with high CI (CI >4, n=9) compared to low CI (n=9). miR-150 signal intensity was 4-fold increased in the high CI group by microarray analysis. deltaCt values of renal miR-150 obtained by qRT-PCR were significantly higher in the high CI (mean 2.83, SD 1.6) vs the low CI (mean 0.65, SD 1.2; p=0.0017 Student's t test) groups. Moreover, the miR-150 deltaCt values showed strong positive correlation with CI scores (Pearson's r=0.73 p<0.0001).
microRNA can be isolated from archived FFPE specimens with good enough quality for miR microarray and qRT-PCR. Renal miR-150 level was differentially expressed in kidney biopsies from patients with proliferative lupus nephritis with either low or high degree of chronicity. The positive correlation of miR-150 with chronicity index suggests that it may be a useful quantitative biomarker for evaluating kidney injury in lupus nephritis.
To cite this abstract, please use the following information:
Zhou, Hua, Hasni, Sarfaraz A., Tandon, Mayank, Alevizos, Ilias, Austin, Howard A., Balow, James E., et al; Renal Mir-150 As Potential Biomarker of Chronicity in Lupus Nephritis. [abstract]. Arthritis Rheum 2011;63 Suppl 10 :1382