Light microscopic demonstration of HCT116 (A-D) and HCT116R (E-H) cells (1 × 106/ml) grown in alginate beads culture. Day 1–3 of cultures (A;E), encapsulated cells revealed cell aggregates, the typical spherical shape of HCT116 and HCT116R (arrows). During the following 7–10 days (B;F), HCT116 and HCT116R cells formed large spheroids and were placed to the channel exterior (arrowheads) when the alginate bead surface was ruptured. With time, days 14–21 days, HCT116 (C-D) and HCT116R (G-H) cells aggregates enlarged and more and more cells migrated from the beads. x24, bar=0.2 mm in all cases.