Figure 4.

Relative resistance to DNA crosslinker-induced cell cycle arrest and apoptosis in a TP53-mutant, patient-derived HNSCC cell line. (A) Percentage of cells arrested in G₂/M as a function of NM concentration for VU974L (black) and OHSU-974 (blue). VU974L retained heightened sensitivity to NM-induced cell cycle arrest, reaching a threshold and then decreasing. By comparison, OHSU-974 exhibited a relative resistance to NM-induced cell cycle arrest. (B) Percentage of apoptotic cells as a function of NM concentration for VU974L (black) and OHSU-974 (red). VU974L underwent NM-induced apoptosis with concentrations of NM that exceeded the threshold for G₂/M arrest. By contrast, OHSU-974 displayed a marked resistance to NM-induced apoptosis at the concentrations of NM tested.