CD44 and gastric cancer: To verify the CD44v8-10-specific binding of the conjugated antibody on the cell surface, we treated CD44v9-ATTO680 to CD44(−) MKN-28, MKN-28 transfected with mock vector, CD44s expressing MKN-28, and CD44v8-10 variant stable MKN-28 cell lines as well as with CD44(−) HDF cells and two CD44v8-10(+) gastric cancer cells (KATO-III and SNU-638) (Fig. 4).