Figure 3. Effect of ¹⁷⁷Lu-octreotate and PARPi on BON-1 spheroids.

(A) The 12 control and 24 treatment spheroids of BON-1 cells were treated with ¹⁷⁷Lu-octreotate and DHQ independently and in combination for 5 days followed by 10 more days of incubation of cells in medium without radiolabel. The representative image of 12 to 24 spheroids over time course of treatment from two independent experiments is shown here. The black core and the peripheral grey zones represent dead and viable parts of the spheroid, respectively. (B) The data pooled from time-course of changes in spheroid volume from 12 to 24 spheroids from two independent experiments described for panel A is plotted as mean ± SEM of fold change in the spheroid volume relative to that at the start of treatment, i.e. Day 0. ^* indicates that all the data points are significantly different between DHQ alone and ¹⁷⁷Lu-octreotate + DHQ treatment groups as well as between ¹⁷⁷Lu-octreotate and ¹⁷⁷Lu-octreotate + DHQ treatment groups from each other from day 8 onwards with P-values ≤ 0.01. (C) Analyses of different parameters of cell proliferation, DNA damage, cell cycle arrest and apoptosis. The 12 control and 24 treatment spheroids were treated as indicated for panel A and harvested on day 15 for immunoblotting proliferation marker Ki67 and other indicated parameters and band intensities were measured and expressed for each panel as described for Figure 2C. The panel for each immunoblot represents one of the two independent identical experiments with similar results.