Notably, the CD44+ GC cell lines isolated from spheroids were significantly more resistant to the cytotoxicity effect of 5-FU and cisplatin than CD44- cell lines, and treatment with vismodegib or SMO shRNA sensitizes CD44+ but not CD44- cells to 5-FU and cisplatin in both in vitro cell lines and in vivo mice xenografts. Here, CD44 is linked to gastric cancer.