Figure 1
From: Microenvironmental Hypoxia regulates FLT3 expression and biology in AML
FLT3 expression in AML is regulated by the oxygen partial pressure.
(A) Heterogeneous FLT3 basal expression in (n = 8; 4 WT, 4 ITD) AML patient samples was analyzed by western blot using whole cell lysates. (B) Expression of FLT3 was independent from its mutational state (optical density (OD) of FLT3 western blot bands normalized to GAPDH shown in Fig. 1; 4 WT, 4 ITD). (C) Western blot of representative examples (n = 4) of FLT3 down-regulating (sample 9 and 10) and non-regulating AML blasts (sample 11 and 12) after 48 h exposure to 1% O2. (D) Fold change of FLT3 OD normalized to β-actin. In FLT3 down-regulating AML cells (n = 8), down-regulation was 80% (p = 0.01), but in non-regulating cells (n = 13), FLT3 expression was virtually unchanged. (E) Clinical data available for n = 24 patients. Overall survival of patients without (n = 9) and with (n = 7) in vitro hypoxia-mediated FLT3 down-regulation (no detectable FLT3 in n = 8 patients). (F) Western blot analysis of whole cell lysates show down-regulation of FLT3 in healthy CD34+ cells in response to 1% O2.
