<p>Cytotoxic effect of DOX-PCL<sub>63</sub>-b-PNVP<sub>90</sub> against parental and DOX-resistant lymphoma cells was determined by 18 h LDH release assay. Cells were incubated with free polymer (carrier), DOX-PCL<sub>63</sub>-b-PNVP<sub>90</sub> micelles or free DOX solution at different concentrations (0.0001, 0.0002, 0.0005, 0.001, 0.01, 0.05, 5 μM) for 18 h followed by measurement of the released LDH according to the manufacture's protocol. (A and B) K-562 and K-562/DOX-R, (C and D) JE6.1 and JE6.1/DOX-R (E and F) Raji and Raji/DOX-R (G and H) DL and DL/DOX-R. (*P<0.05, **P<0.01, ***P<0.001, ****P<0.0001 in control versus experimental group) data represents mean ± SD, n = 3.</p
