Figure 2: Influence of oxygen on cell migration on a collagen substrate in the MDA-MB-231 and MCF-7 breast adenocarcinoma cell lines, as determined using the Oris™ Cell Migration assay. Note: (A) Acute (3-hour) exposure of MCF-7 cells to 30% or 60% O2 significantly enhanced subsequent migration into the exclusion zone; MDA-MB-231 migration was similarly increased by 60% O2. Values shown are mean (SEM) versus values for matched cells exposed to control gas at the same time (5 ≤ n ≥ 6). *P ≤ 0.05, vs. control gas. (B) Representative images of MDA-MB-231 migration in the Oris™ Cell Migration Assay; from left to right: medical air, 30% O2, 60% O2, 80% O2, and negative control. (C) Representative images of MCF-7 migration in the Oris™ Cell Migration Assay; from left to right medical air, 30% O2, 60% O2, 80% O2, and negative control.