Gene expression changes during resistance toward vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI) therapy in renal cell carcinoma (RCC). Homo sapiens

This study was performed to understand the gene expression changes that accompany treatment of renal cell carcinoma (RCC) with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI) therapy. Human RCC cell lines were implanted into the flanks of nude beige mice, allowed to reach 12mm in long axis, and then treated with TKIs (sunitinib or sorafenib). Tumors were excised at 2 timepoints (prior to any therapy and at the 20mm endpoint of the study) and gene expression analysis was performed. Overall design: Sunitinb or sorafenib were administered to mice bearing either 786-O or A498 xenografts. Mice were sacrificed and tumors excised for RNA extraction at pretreatment size of 12mm, or at 20mm, the mandated maximum tumor size allowed at our institution.