Figure 7From: Hypoxia stimulates migration of breast cancer cells via the PERK/ATF4/LAMP3-arm of the unfolded protein responseKnockdown of LAMP3 reduces invasion of spheroids into collagen. (A) Expression of LAMP3 mRNA in control cells versus LAMP3 knockdown cells. (B) Spheroid size of MDA-MB-231 control and LAMP3 knockdown spheroids after 4 days of growth. Results are from two independent experiments with 32 replicates each. (C) F-actin staining of MDA-MB-231 spheroids of control and LAMP3 knockdown cells, after 6 days of invasion in collagen. Bar is 100 μm, original magnification is 50 x. (D) Surface of collagen invaded by MDA-MB-231 control and LAMP3 knockdown spheroids during 72 hours. (E) Collagen invasion of a mixed MDA-MB-231 spheroid after 6 days. Control cells were labeled with CellTracker Green and LAMP3 knockdown cells were labeled with CellTracker Orange. Control and LAMP3 knockdown cells were mixed in a 1:1 ratio. Bar is 100 μm, original magnification is 100 x. (F) Quantification of E. The total amount of green and red signal was analyzed in five different zones: the spheroid body and four consecutive invasive zones, n = 5. LAMP3, lysosomal-associated membrane protein 3.Back to article page