KKU-055 and KKU-213A were seeded at 3 × 10 5 into a 6-well plate. After seeding overnight, the cells were treatedwith PL or BTZ or co-treatment of PL and BTZ for 24 h. After that, the cells were harvested and fixed with cold 70%ethanol and incubated for 2 h at 4 °C.