Germline Genetic Biomarkers of Sunitinib Efficacy in Advanced Renal Cell Carcinoma: Results From the RENAL EFFECT Trial
Biomarkers to guide metastatic renal cell carcinoma treatment to improve outcomes remain elusive. We examined previously identified single nucleotide polymorphisms in sunitinib-treated patients' samples from the RENAL EFFECT trial, to evaluate their predictive/prognostic value. Significant associations betweenCLLU1, IL2RA, CXCL8, andSH3GL2variants and sunitinib efficacy were observed, suggesting that further analysis of these single nucleotide polymorphisms is warranted.Background:
Sunitinib, the vascular endothelial growth factor pathway inhibitor, is an established standard-of-care for advanced renal cell carcinoma (RCC). This study aimed to assess correlations between candidate germline single nucleotide polymorphisms (SNPs) and sunitinib efficacy in patients from the RENAL EFFECT trial (NCT00267748), a randomized phase II study in patients with metastatic RCC comparing the 4-weeks-on/2-weeks-off schedule and a continuous daily dosing schedule.Patients and Methods:
Informed consent for pharmacogenetics research was obtained from 202 out of 289 treated patients in the trial. Associations between 9 SNP variants (CXCL8, LOXL2, CCDC26, SH3GL2, CLLU1, IL2RA, AURKB, and 2 SNPs on Chromosomes 7 and 12) and progression-free survival (PFS), objective response rate, and overall survival were assessed using Kaplan-Meier analysis, Cox proportional hazard model, and the Fisher exact test.Results:
CXCL8 rs1126647 A/A versus A/T (P = .004) or T/T (P < .0001) and SH3GL2 rs10963287 C/C versus C/T (P = .005) or T/T (P = .018) were associated with improved overall survival in all patients. CLLU1 rs525810 A/A genotype versus A/G (P = .014) or G/G (P = .048) was associated with improved PFS in the continuous daily dosing arm. IL2RA rs7893467 T/G versus T/T was associated with improved PFS (P = .034) in the 4-weeks-on/2-weeks-off arm and objective response rate (P = .034) in all patients. No significant associations between improved efficacy and genotype were found for other SNPs.Conclusion:
Germline variants in CLLU1, IL2RA, CXCL8, and SH3GL2 warrant further retrospective study in independent cohorts of patients with metastatic RCC treated with vascular endothelial growth factor-class inhibitors, to test their biological significance and potential clinical fitness as biomarkers to guide treatment.