Fig. 5
Therapeutic effect of Zt/g4-DM1 on BC and NSCLC cell-derived tumors. a Athymic nude mice (five mice per group) were subcutaneously inoculated with 5 × 106 BC and NSCLC cells. Upon tumor volume reaching at ~100 mm3, Zt/g4-DM1 was injected through tail vein at 20 mg/kg in a Q12 × 2 regimen. Control mice were injected with CmIgG-DM1. Tumor growth was monitored every 4 days by measuring tumor volume. The percentages of inhibition were calculated by a formula: 1-(average tumor volume from Zt/g4-DM1 treated group)/(average tumor volume from control mice) × 100 %. b Individual tumors from the control and experimental groups were collected and weighed at day 36, 44, or 52 dependent on individual tumor growth curves. The percentages of average tumor reduction were calculated by a formula: 1- (average tumor weight from Zt/g4-DM1 treated group)/(average tumor weight from control mice) × 100 %. c The TSCs of Zt/g4-DM1 in vivo. The growth curve of individual xenograft tumors from BC or NSCLC was analyzed with dynamics of Zt/g4-DM1 at 20 mg/kg in the Q12 × 2 regimen. Zt/g4-DM1 in vivo has a terminal half-life (t½) of 6.01 days [25], which was plotted to the tumor regrowth curve. TSCs for H2228, H358, and T-47D cell xenograft models were determined as the minimal dose of Zt/g4-DM1 required to balance the tumor growth and inhibition. d The effect of Zt/g4-DM1 on mouse body weight. Control and tumor-bearing mice after Zt/g4-DM1 treatment as described in A were monitored every 4 days for changes in their body weights. The percentages of changes in mouse body weight were calculated as previously described [25]