Down-regulated expression of CD44 impacted cell proliferation in vivo . (A) Representative pictures of tumor taken at the time of killing were shown. (B) Volume of subcutaneously formed tumors. Tumor volume was calculated asπLW2/6 for 30 days. (C) subcutaneous tumor outgrowth of CD44 shRNA and scramble vector-expressing K562 cells. The experiment was carried out blinded and repeated twice with similar results. Data shown were averages from five mice in each group and were presented as Mean ± SD. *, P < 0.05 by Student’s t-test.