Fibronectin-adhered MM cells remain sensitive to UCN-01/PD184352–induced apoptosis.

MM.1S and MM.1R cells were seeded into 96–well plates coated with fibronectin, and cells remaining in suspension removed as described in “Materials and methods.” Adherent cells and cells in suspension were separately exposed to 250 nM doxorubicin (Dox), 10 μM melphalan (Mel), 10 μM dexamethasone (Dex), or 10 μM PD184352 + 150 nM UCN-01 for 24 hours, after which the extent of apoptosis was determined by evaluating Wright-Giemsa–stained cytospin preparations as described previously. Values represent the means ± SD for 3 separate experiments performed in triplicate. * indicates data values are significantly less than values for cells in suspension; P < .01.