Proliferation, invasion, and apoptosis of 5T2MM cells during disease progression.

5T2MM cells at different stages of disease progression were sorted as described in Figure 1. Proliferation was assessed by incubation of the cells with bromodeoxyuridine for 1 hour followed by flow-cytometric analysis of nuclei. Invasion was measured by assessing migration of the cells through Matrigel-coated Transwell filters overnight. Apoptosis was analyzed by staining of the cells with annexin V and propidium iodide after overnight incubation on bone marrow stromal cells. Data are illustrated as a function of the corresponding paraprotein concentration, which is an indicator of the tumor stage. Each point represents data from one mouse in an independent experiment.