Figure 4. Loss of hypoxia-regulated autophagy increases engraftment of MDA-MB-231 cells into the lung.

MDA-MB-231 cells expressing HRE-Empty or HRE-dnULK1 were pre-incubated in normoxia (N) or hypoxia (H) (1% O2) for 48 hours and subjected to tail vain injection into NSG mice (10 mice per group). a, Quantification of metastasis of MDA-MB-231 xenografts to the lungs via luciferase expression (photons/sec) (mean ± SEM, n=10, **p<0.01, ***p<0.001, repeated-measure ANOVA). b, Representative images of luciferase expression from MDA-MB-231 HRE-dnULK1 and HRE-Empty cell lines within the lungs of NSG mice over a 6 week time period. c, Quantification of lung metastasis as measured by the percent of tumor tissue within a lung section (mean ± s.d, n=8 per group (4 for HRE-dnULK1 at 1% 0₂), ***p<0.001, t-test). d, Representative images of hematoxylin and eosin (H&E) stained lung tissues.