Similarly, Harada et al.[21] found massive accumulation of MMP-2 and MMP-9 in human benign cystic fluids.Obermuller et al. [22] found the upregulation of MMP-14 in a rat modelof autosomal-dominant polycystic kidney disease and advocated that TIMPs arepromising biomarkers for treating polycystic kidney. The gene discussed is MMP9; the disease is autosomal dominant polycystic kidney disease.