Fig. 3.

In vitro cell growth inhibitory activity of LSR-ADC. (A) NOVC-7C, OVCAR3, and ES2 cells were treated with the anti-LSR mAb (#16-6) or with the control IgG antibody for 144 h. Neither antibody inhibited the cell growth in any of the cell lines. (B) The cells were treated with LSR-ADC or with mouse IgG2a-ADC (control-ADC) for 144 h. LSR-ADC significantly inhibited the growth of LSR-positive NOVC-7C and OVCAR3 cell lines (as compared to control-ADC). In the LSR-negative ES2 cell line, neither treatment had any inhibitory effect. (C) Induction of G₂/M phase cell cycle arrest in NOVC-7C and OVCAR3 cells treated with LSR-ADC. Cells were treated with either 16 nM control-ADC or 16 nM LSR-ADC. After 24 h, a cell cycle analysis was performed by flow cytometry, with the use of propidium iodide DNA staining. **: p < 0.01 (as determined by one-way ANOVA, followed by a Dunnett's post hoc test). (D) Induction of apoptosis in NOVC-7C and OVCAR3 cells treated with LSR-ADC. Cells were treated with control-ADC or LSR-ADC for 48 h. Caspase-3/7 activity was monitored by using the Caspase Glo 3/7 assay system. The caspase-3/7 activity that was relative to untreated cells was detected in cells treated with increasing concentrations of LSR-ADC. **: p < 0.01 (as determined by Student's t-test).