Fig. 5
Combination of PDX with DAC in 3D-culture. Parental or PDX-resistant cells were incubated with various concentrations of PDX and DAC (CEM and CEM/P cells:100 μM, MOLT4 and MOLT4/P cells:10 μM) for 72 h and cell viability was measured using the XTT assay. Individual IC50 values were determined from curve fitting. The combination index (CI) of PDX and DAC was calculated using COMPUSYN software (http://www.combosyn.com). CI defines synergism (CI < 1), additive effect (CI = 1) and antagonism (CI > 1). Statistical analysis was performed using two-tailed paired Student’s t-tests. N.R: not reached