Fig. 3

LAM1:PIK3CA^E545K cells do not exhibit increased resistance to etoposide and radiation in vitro. A LAM1^EV and mutant cells were seeded into 96-well plates at a density of 2400 cells per well. After 24 h cells were treated with an extended dose range of etoposide concentrations from 0.125 to 32 µM and plate readings were completed following incubation for 72 h. Dose–response curves were generated using Prism 8 GraphPad Software and IC₅₀ values were calculated for each cell line. B The LAM1^EV and LAM1:PIK3CA^E545K cell lines were seeded at a density of 250 (0 Gy), 500 (1 Gy), 1000 (2 Gy) and 2000 (4 Gy) cells per well, with respective doses of radiation shown in parenthesis applied after 24 h. Cells were incubated for a one-week period with cell media changed every three days. Following this incubation period, cells were fixed and stained with 0.5% crystal violet. Brightfield microscopy was used to visualize colony formation and colonies were quantified, with a colony defined as being ≥ 50 cells. Quantification was completed by calculating the plating efficiency for each control cell line and the respective survival fraction as described by Franken et al. [14]