Lcn2 is one of the leading upregulated genes in kidneys from Col4a3KO mice.30 In our current study, expression of Lcn2 was highly elevated in the kidney, and to a lower extent in the hearts, but not in bone or bone marrow of 23-week-old Col4a3KO mice with advanced CKD compared to WT mice (Fig. 2b). Here, LCN2 is linked to chronic kidney disease.