AXL and enolase 2 associate with therapy resistance to tyrosine kinase inhibitors lenvatinib and cabozantinib in renal cancer cells.

Abstract

Resistance to tyrosine kinase inhibitors (TKI) remains a major clinical challenge in the treatment of renal cell carcinoma (RCC). In this study, we established renal cancer cell models resistant to the TKI lenvatinib and cabozantinib to investigate the molecular mechanisms underlying acquired resistance. Using a quantitative proteomic approach, we profiled protein alterations associated with the resistant phenotype. A moderate-to-strong linear correlation was observed between the proteomic profiles of drug-treated control cells and matched resistant cells (Pearson r = 0.80 for lenvatinib and r = 0.66 for cabozantinib), suggesting shared alterations associated with the resistant phenotype. Notably, 35 proteins were commonly upregulated, and 40 proteins were commonly downregulated, across both resistant models, highlighting shared adaptive mechanisms driving cross-resistance. Among these, AXL tyrosine kinase receptor and enolase 2 (ENO2) emerged as key resistance-associated druggable targets that are overexpressed in clear cell RCC (ccRCC) tumors and associated with patient poor overall survival. Functional validation confirmed that pharmacological inhibition of AXL and ENO2 effectively reduced cell viability of renal cancer cells. These findings unveil association of AXL and ENO2 with resistant phenotype in RCC cells, and reveal AXL and ENO2 as promising alternative therapeutic targets in renal cancer. SIGNIFICANCE: Acquired resistance to tyrosine kinase inhibitors (TKIs) remains a major limitation in the treatment of renal cell carcinoma, underscoring the need to better understand the underlying mechanisms. In this study, we established lenvatinib- and cabozantinib-resistant renal cancer models to investigate shared resistance pathways. Quantitative proteomic analysis identified 35 proteins consistently upregulated in resistant cells, pointing to common adaptive mechanisms. Among these, AXL and enolase 2 were also overexpressed in patient tumors and associated with poor prognosis in ccRCC. Functional assays showed that inhibition of AXL and enolase 2 reduces the viability of renal cancer cells. Together, these findings identify proteins associated with the resistant phenotype that remain pharmacologically targetable and highlight potential targets for improving treatment of drug-refractory renal cancer.