Effect of decreased expression of CD44 on cell proliferation in vitro . Colony-forming potential was analyzed by semisolid methylcellulose medium. (A) Representative photographs of colony formation for K562 cells transfected with CD44shRNA or control vector, respectively. Upper panel (40×) showed the number of colonies, and lower panel (100×) showed the size of colonies. (B) Colony numbers for different K562 cell lines of each sight under microscope were shown. (C) Colony radius under microscope was also shown. *, P < 0.05, **, P < 0.01, compared with the control.