2.12. In vivo antitumor efficacy

The B16F10 subcutaneous melanoma model was established by subcutaneously inoculation of 1.0 × 10⁶ B16F10 cells into the abdomen. When the melanoma reached about 50 mm³, mice were grouped and received PBS, PDDN (81.7 mg kg⁻¹), free DOX (3 mg kg⁻¹) or PDDN-DOX (84.7 mg kg⁻¹) through the tail vein on days 0, 3, 6, and 9. Mouse tumor volumes and body weights were recorded every two days. Tumor volumes were calculated as V = length × width²/2. The tumor inhibition rate (%) = (V_control-V_sample)/V_control × 100%. Herein, V_control and V_sample represented the average tumor volumes in the control and sample groups, respectively.

The metastatic pulmonary melanoma model was established by an injection of 1 × 10⁵ B16F10 cells per mouse through the tail vein. After five days, mice were randomly grouped and treated with PBS, PDDN (81.7 mg kg⁻¹), free DOX (3 mg kg⁻¹), or PDDN-DOX (84.7 mg kg⁻¹) by tail vein administration. Mice were treated on days 5, 8, 12, and 18 after the implantation of B16F10 cells. On day 27, mice were sacrificed and the treatment effect in the different groups was evaluated.