Figure 4. High-frequency self-renewal of PrCa cell spheroids in Matrigel suspension cultures.

Low passage, adherent PrCa cells (#76, tr 2) were trypsinized and suspended in Matrigel in medium 6⁺⁺⁺. Suspension cultures were grown for 14 days and spheres of replicate cultures were harvested on days 1, 4, 7, 9, 11 and 14. Cultures were digested with dispase, pelleted on microscope slides by cytocentrifugation and fixed with methanol. (A) The size of the spheres was determined by counting the cells of >200 stained spheres at each time-point. (B) Early and late time-point spheres were photographed under an inverted microscope. (C) Representative harvested spheres growing 1, 4, 7, 11 and 14 days in Matrigel cultures, and deposited on microscope slides for imaging, counting and antibody staining.