3H-thymidine incorporation by CLL cells in coculture with NLCs is decreased after treatment with PCI-32765.3H-thymidine uptake in CLL cells cocultured with NLC was measured with a scintillation counter. Cells were either left untreated (control) or incubated with 2 different concentrations of PCI-32765 (0.5 or 1.0μM) for 24 hours (left panel) or 48 hours (right panel), respectively. The uptake of the tritiated nucleoside was significantly decreased in cells treated with the inhibitor. In untreated CLL cells, a slight increase between 24 and 48 hours was observed, suggesting proliferation in a small subset of CLL cells cocultured with NLC. In CLL cells treated with PCI-32765 this proliferation was not observed. Shown are mean values ± SEM of 9 patients. *P ≤ .05.
