Fig. 5

Phototoxicity of PIC–Nal and PIC in OVCAR-5 and U87 cells. a Cells were incubated with PIC or PIC–Nal at a fixed BPD concentration (0.25 µM) for 24 h prior to light activation (690 nm, 20 J/cm², 150 mW/cm²). Cell viability was determined by MTT assay at 24 h post-light activation. PIC–Nal is more phototoxic than PIC in b high EGFR expressing OVCAR-5 but not in c low EGFR expressing U87. (n > 3; *P < 0.05, ***P < 0.001; n.s.: not significant; one-way ANOVA, Tukey’s posthoc test)