Semaphorin-3C Is Upregulated in Polycystic Kidney Epithelial Cells and Inhibits Angiogenesis of Glomerular Endothelial Cells

<b><i>Background:</i></b> Polycystic kidney disease (PKD) is a hereditary disease characterized by cyst formation in the kidneys bilaterally. It has been observed that semaphorin-3C (SEMA3C) is overexpressed in polycystic kidney epithelial cells. It is hypothesized that upregulated SEMA3C would contribute to survival of polycystic kidney epithelial cells. Furthermore, as the kidney is a highly vascularized organ, the secreted SEMA3C from PKD epithelial cells will affect glomerular endothelial cells (GECs) in a paracrine manner. <b><i>Methods:</i></b> To evaluate the effect of SEMA3C on renal cells, siSEMA3C-treated PKD epithelial cells were used for further analysis, and GECs were exposed to recombinant SEMA3C (rSEMA3C). Also, co-culture and treatment of conditioned media were employed to confirm whether PKD epithelial cells could influence on GECs via SEMA3C secretion. <b><i>Results:</i></b> SEMA3C knockdown reduced proliferation of PKD epithelial cells. In case of GECs, exposure to rSEMA3C decreased angiogenesis, which resulted from suppressed migratory ability not cell proliferation. <b><i>Conclusions:</i></b> This study indicates that SEMA3C is the aggravating factor in PKD. Thus, it is proposed that targeting SEMA3C can be effective to mitigate PKD.