Fig. 3
Comparison of growth of prostatospheres formed on dishes coated with different concentrations of agar and commercial ultra-low attachment (ULA) culture dishes. a Representative images of spheres derived from single-cell suspensions of DU145 cells (1.5 × 103 cells suspended in 1–2 mL serum-free medium) formed on 0.6–2.0% agar-coated dishes and ULA culture dishes. Inserts show spheres at high magnification. Bars: 200 μm. b and c Analysis of the number of spheres and their sizes scored on dishes coated with 0.6–2.0% agar and ULA plates. Spheres of at least 50 μm in size were scored under microscope. d Upper: schematic diagrams show the growth of sphere into the agar layer in dishes coated with not more than 0.3% agar and its free-suspension growth on dishes coated with at least 0.3% agar. Lower: representative images show the loosely attached spheres on not more than 0.3% agar plates or non-attached spheres formed on at least 0.3% agar-coated plates. Arrow indicates the edges of spheres being grown into the not more than 0.3% soft agar layer. Bars: 100 μm