The tumorigenic potential of cells from each fraction.

“Tumor incidence” indicates the average incidence of tumors in each mice (6 mice in each group, 6/6 means 6 tumors in 6 injected mice). “Tumor diameter” refers to the average diameter of tumors in each group (−, no macroscopic tumor; +, <0.2 cm; ++, 0.2–0.5 cm; +++, >0.5 cm). “Metastasis incidence” means the average incidence of the liver neoplasia in each group (6/6 means 6 liver neoplasias found in 6 mice). All results were independently viewed by three different researchers. *FIII vs. F0, FI, FII, FIV (the same number), P<0.01.