Sunitinib Treatment of VHL C162F Cells Slows Down Proliferation and Healing Ability via Downregulation of ZHX2 and Confers a Mesenchymal Phenotype

Simple Summary Mutations of the von Hippel-Lindau (VHL) gene lead to VHL disease in patients. It is characterized by numerous benign and malignant tumors in different organs, as highly vascularized clear cell renal cell carcinomas (ccRCCs). The aim of this study was to examine the consequences of VHL-C162F mutation on morphology, proliferation, ability to form colony and healing ability of renal carcinoma cells. We found that VHL-C162F cells display a higher healing ability than wild type (WT) VHL cells. This was associated with a high expression of ZHX2, an oncogenic driver of ccRCCs. More importantly, sunitinib treatment resulted in a decreased proliferation of VHL-C162F cells. This was associated with ZHX2 inhibition and downregulation of P-ERK. Such treatment also confers a more mesenchymal profile which is not in favor of survival for patients with VHL-C162F disease.Abstract von Hippel-Lindau (VHL) disease, due to mutations of the tumor suppressor VHL gene, is a rare hereditary syndrome with a high risk of developing clear cell renal cell carcinoma (ccRCC). We asked whether the VHL-C162F mutation interferes with proliferation, migration, healing and forming colony ability by using wild-type VHL (WT VHL) and VHL-C162F reconstituted cells. We then analyzed the in vitro impact of the sunitinib treatment on VHL-C162F cells. We showed that VHL-C162F mutations have no impact on cell morphology, colony formation and migration ability but confer a significant higher healing ability than in WT VHL cells. RNA sequencing analysis revealed that VHL-C162F mutation upregulates genes involved in hypoxia and epithelial mesenchymal transition (EMT) pathways by comparison with VHL WT cells. We next showed a decrease in healing ability in VHL-C162F cells depleting on ZHX2, an oncogenic driver of ccRCC, highlighting the potential involvement of ZHX2 in aggressiveness of the VHL-C162F cells. Moreover, we found that sunitinib treatment inhibits ZHX2 expression and induces a reduced proliferation correlating with downregulation of P-ERK. Sunitinib treatment also conferred a more mesenchymal profile to VHL-C162F cells with significant downregulation of E-cadherin and upregulation of N-cadherin, Slug and AXL. Sunitinib therapy may therefore promote disease progression in VHL-C162F patients.