TY - JOUR T1 - CD44 Is Involved in Sunitinib Resistance and Poor Progression-free Survival After Sunitinib Treatment of Renal Cell Carcinoma JF - Anticancer Research JO - Anticancer Res SP - 4875 LP - 4883 DO - 10.21873/anticanres.15301 VL - 41 IS - 10 AU - YOHEI SEKINO AU - KENSHIRO TAKEMOTO AU - DAIKI MURATA AU - TAKASHI BABASAKI AU - KOHEI KOBATAKE AU - HIROYUKI KITANO AU - KENICHIRO IKEDA AU - KEISUKE GOTO AU - SHOGO INOUE AU - TETSUTARO HAYASHI AU - DAIKI TANIYAMA AU - MASANOBU SHIGETA AU - KAZUYA KURAOKA AU - KOJI MITA AU - MAYUMI KANEKO AU - KAZUHIRO SENTANI AU - NAOHIDE OUE AU - JUN TEISHIMA Y1 - 2021/10/01 UR - http://ar.iiarjournals.org/content/41/10/4875.abstract N2 - Background/Aim: Sunitinib continues to be administered as a first-line therapeutic agent in metastatic renal cell carcinoma (mRCC). This study aimed to examine the role of CD44 in sunitinib resistance and as a predictive marker in mRCC. Materials and Methods: We analyzed the effect of CD44 knockdown on sunitinib resistance in RCC cell lines using WST-1 assays. CD44 expression in mRCC patients treated with first-line sunitinib was determined by immunohistochemistry. We validated the findings of this study by in silico analysis. Results: CD44 knockdown increased sensitivity to sunitinib. Immunohistochemical analysis revealed that 19 (34.5%) of 55 mRCC cases were positive for CD44. CD44-positive cases were associated with poor progression-free survival (PFS) after first-line sunitinib treatment. In the JAVELIN 101 study, high CD44 expression was significantly associated with poor PFS after sunitinib but not after avelumab + axitinib therapy. Conclusion: CD44 is involved in sunitinib resistance and may be a promising marker for sunitinib treatment in mRCC. ER -