Cell sorting results and morphological observation. (A) Sorting of SP cells using Hoechst 33342 (1.07 ± 0.32% to total cells) (left). When the cells preincubated with verapamil to block the ATP transporter, the SP proportion was reduced to 0 (right). (B) After plating, SP and non-SP cells were observed every 6 hour, SP cells were more adherent than non-SP cells and showed colony-like growth. The image was obtained in 24 hour (×100).