DKK1 and pulmonary fibrosis: Notably, in the study of Lrp5 deficiency in pulmonary fibrosis, the authors also acknowledged that LRP5 may play a β-catenin-independent role to regulate fibrosis, supporting our finding in the kidney.5 LRP6, another LDLR family member, mediates the inhibitory effect of DKK-1 through the TGF-β-JNK signaling axis in renal pericytes,40 suggesting a role of LRP6 independent of β-catenin.