Figure 5.

D3-GPC2-PBD is potently cytotoxic to GPC2-expressing SCLCs

(A) Quantification of internalization of D3-GPC2-IgG1-Red in neuroblastoma and SCLC cell lines.

(B) Growth plots of SCLC cell lines 4 days after treatment with D3-GPC2-PBD.

(C) Western blot of H526 cells 3 days after treatment with D3-GPC2-PBD.

(D) Fold-change caspase-3/-7 levels of H526 cells 4 days after treatment with D3-GPC2-PBD.

(E) H526 xenograft volumes after treatment with D3-GPC2-PBD (n = 6–7 mice/cohort; represented as mean ± SEM).

(F) Progression-free survival (PFS) of treatment arms in (E). Median survival of 2.8 weeks for vehicle and >14.0 weeks for 1 mg/kg ADC, 1 mg/kg ADC × 4, and 3 mg/kg ADC treatment cohorts.

Data in (A), (B), and (D) represent mean ± SEM from a representative experiment done in technical triplicate with each experiment being done at least two independent times. Blue arrows in (E) and (F) represent initial ADC dose, and red arrows indicate subsequent 3 ADC doses for the 1 mg/kg ADC × 4 treatment cohort. ∗∗p < 0.001; ∗∗∗p < 0.0001.

See also Figure S7.