Effect of inhibitors of phosphatidylinositol 3-kinase on SDF-1α–up-regulated VLA-4–dependent myeloma cell adhesion and chemotaxis.

(A) BCECF-AM–labeled NCI-H929 cells were treated for 30 minutes in adhesion medium without (Nil) or with wortmannin (Wort) (0.2 μM) or Ly294002 (Ly) (20 μM). After cell treatment with the inhibitors, SDF-1α (100 ng/mL, 1 minute) was added, and cells were allowed to adhere to FN-H89– or sVCAM-1–coated wells for 2 minutes. Adhesions were quantified in a fluorescence analyzer. Each panel shows data representing the mean ± SD of triplicate samples from one representative result of at least 4 separate experiments. (B) Comparison of the effects of wortmannin and pertussis toxin on the chemotaxis of myeloma NCI-H929 cells in response to SDF-1α. Cells were preincubated with or without the inhibitors and allowed to migrate for 3 hours at 37°C to an SDF-1α (100 ng/mL)-containing lower chamber. Data represent the mean ± SD of duplicate samples from a representative result of 3 separate experiments.