CD44 Is Involved in Sunitinib Resistance and Poor Progression-free Survival After Sunitinib Treatment of Renal Cell Carcinoma.

BACKGROUND/AIM Sunitinib continues to be administered as a first-line therapeutic agent in metastatic renal cell carcinoma (mRCC). This study examined the potential role of p53 in sunitinib resistance and as a predictive marker in mRCC. MATERIALS AND METHODS We analysed the effects of p53 knockout on sunitinib resistance. p53 expression in 53 mRCC patients receiving first-line sunitinib was determined immunohistochemically. We performed in silico analysis to examine the predictive value of p53 in mRCC. RESULTS WST-1 assays showed that p53 knockout decreased sensitivity to sunitinib. Sunitinib and nutlin-3 together suppressed cell growth. Immunohistochemistry revealed 11 p53-positive cases among 53 patients with mRCC. Kaplan-Meier analysis showed that p53-positive cases tended to be associated with poor progression-free survival (PFS) after first-line sunitinib treatment. In the JAVELIN 101 study, TP53 mutation was significantly associated with poor PFS after sunitinib treatment. CONCLUSION p53 may be involved in sunitinib resistance and represent a valuable marker for sunitinib treatment in mRCC.