Fig. 2.
Morphologic features of NB4 and NB4-AsR cell lines on RA, As2O3 or the combined treatment. NB4 and NB4-AsR cells were treated for 5 days, respectively, without (A), with 10−6 mol/L RA (B), 10−6 mol/L As2O3 (C) or with the combination of 10−6 mol/L RA plus 10−6mol/L As2O3 (D).