Figure 3
The SDF-1/CXCR4 axis displays different features under 6% and 21% O2 levels. (A) SDF-1 (50 ng/mL) leads to a statistically significant decrease of CXCR4 under normoxia in OCI-AML3 and U937 cell lines. However, under 6% O2, exposure to the same amount of SDF-1 leads to a significant increase of CXCR4 expression. (B) Dose-response curves of leukemic cell lines reveal a significant increase (OCI-AML3 maximum 1.6-fold, U937 maximum 2.2-fold) in migration toward SDF-1 at 6% O2. Graphs show mean and SD. (C) Western blotting of OCI-AML3 after stimulation of CXCR4 with SDF-1 under 6% and 21% O2. Hypoxic cells show a dramatic increase in Akt and Erk stimulation, but no response to SFD-1.
