Flt3 activates the canonical Wnt signaling pathway. (A-B) 32D cells stably expressing the indicated Flt3 constructs were starved from growth factors (GF) for 12 hours, exposed to the indicated cytokines for 6 hours with control-conditioned medium or Wnt3a-conditioned medium, and lysed, and the indicated protein was analyzed by Western blot analyses. (A) Expression of β-catenin in the presence of Wnt3a. (B) Expression of β-catenin in the absence of Wnt3a. (C) Densitometry of β-catenin. The bar diagram indicates the intensity of the β-catenin bands shown in Figure 3B. □ indicates no GF; ▨, FL; ▪, IL-3. For densitometry analyses we used an INTAS camera (Epichem3 Darkroom) and the GelPro Analyser (1D-Gel ToolBar) software. (D) 32D/Flt3-ITD cells (in the absence of exogenous growth factors) were exposed to 300 nM PKC412 for the indicated periods. The cells were lysed and subjected to Western blot analyses for β-catenin. (E) Expression of β-catenin in patients with ITD-negative and ITD-positive AML. Pt. ID indicates patient identification number.
