Fig. 2.

In vitro cytotoxicity and in vivo anticancer activity of Dox-gluRDVs. (A–E) These cells, including B16F10 cells (A), HT-29 cell (B), MES-SA cells (C), PC3 cells (D), and TOV21G cells (E), were incubated for 24 h with increasing antitumor drug concentrations of free Dox, Dox-gluRDVs or a mixture of gluRDVs and free Dox without conjugation procedure (gluRDVs/free Dox) and then processed for MTT cell viability assay (p-values: * < 0.05 as compared with control; # < 0.05 as compared with free Dox). (F) Tumor growth curves of different groups of B16F10-bearing mice (n = 4 to 6 mice per group) (p-values: * < 0.05 as compared with control). At the low concentration of free Dox used (0.5 mg/kg), Dox did not show significant tumor growth inhibition while the antitumor activity of Dox was significantly elevated at high concentration of 5 mg/kg as compared to control. To avoid the possibility of immunologic responses by xenogeneic RDVs, Dox-gluRDVs at 0.1 mg/kg of Dox was used by comparison with the same amount of gluRDVs as the one used in the Dox-gluRDVs. At that concentration, gluRDVs did not show inhibitory effect on tumor growth. No difference of animal body weight between groups was observed (data not shown).