In addition, renal RNASE1 expression increased with LN severity and was significantly higher in class IV ± V LN than in class III ± V or class V LN, correlating with the pathological activity index.<h4>Discussion</h4>RNASE1 is a promising biomarker reflecting both systemic disease activity and renal involvement in SLE. Here, RNASE1 is linked to lobular neoplasia.