Figure 4.

Glucose starvation rescues CQ-dependent cell death. (a and b) 4T1 cells were incubated in four different nutrient conditions: (1) full-nutrient DMEM (Ctrl); (2) serum-free DMEM; (3) serum- and glucose-free DMEM; or (4) serum- and amino-acid-free media (EBSS); ±CQ (25 μM) as indicated. After 24 h incubation, clonogenic cell viability was measured (% of control, n=3 experiments±S.E.M.). ***P<0.001 by one-way ANOVA. (c) 4T1 cells were treated with the indicated nutrient conditions ±CQ for 4–16 h and then measured for cell viability as in (a) (n=3 experiments±S.E.M.). (d and e) 4T1 cell growth and morphology were monitored using live-cell imaging during nutrient and CQ treatments as indicated. (d) Images shown from the 23 h time point. Arrows indicate CQ-induced cell condensation and death. Arrowhead indicates vacuolated cell death. (e) Cell viability (% of imaging area containing cells, average ±S.E.M., N=2 experiments) are shown over the 48 h experiment. After 24 h nutrient ±CQ treatments, full-nutrient drug-free media was replenished (arrow) and cells were further monitored