Figure 6. Cell cycle-dependent regulation of cisplatin response.
(A, B) Schematic of palbociclib (Palbo) and thymidine (Thy) protocols used to synchronise FUCCI expressing A549 cells in G1, G1/S, and S phase prior to 2 hr cisplatin pulse treatment. Specifically, G1 cells were released from palbociclib and pulsed immediately with cisplatin (Palbo + Cis at G1). G1/S cells were pulsed with cisplatin at 6 hr post release from palbociclib (Palbo + Cis at G1/S), or alternatively G1/S phase cells targeted by treatment with cisplatin 2 hr prior to release from thymidine (Thy + Cis at G1/S). Finally, S phase cells targeted by pulsing with cisplatin at 4 hr post-thymidine release (Thy + Cis at S). The fate of individual cells (n = 50) was tracked by time-lapse microscopy, with images taken every 30 min for 72 hr. (C) Quantification of cell fate outcomes from (A), including G1 arrest before mitosis (G1 ABM), G1 arrest after mitosis (G1 AAM), death before mitosis (DBM), and death after mitosis (DAM) and proliferative (Prolif.). (D) Quantification of the total number of cell divisions observed in each condition (n = 50). Mean is shown, statistical significance was determined by one-way ANOVA with Tukey’s correction for multiple comparisons (****p<0.0001, *p<0.05).
