Abstract： Objective To make sure whether or not Bcrp1 is the marker of cervical cancer stem cells or not by studying the invasive ability and formation of tumors of Bcrp1 + phenotype HeLa cells.Methods The tumor cell migration and invasion assay were used by boyden chamber to identify the invasive ability of Bcrp1 + phenotype HeLa cells.The formation of tumors in vivo experiments were completed,in which the two groups of cells with different concentrations were inoculated in non obese diabetes-severe combined immunodeficiency disease ( NOD/SCID ) mice ( 1 × 104,1 × 105,1 × 106/ml ) and the differences of time,rate and volume in the formation of tumors between two groups were observed.Results ( 1 ) In the invasion assay,the amount of cells that invaded through the artificial basement membrane in Bcrp1 + group were 99 ± 14,which was significantly greater than those in Bcrp1- group ( 57 ± 13,P ＜ 0.05 ) ; the length of the Bcrp1 + group was ( 366 ± 52 ) μm,which was significantly greater than the Bcrp1 - group ( 301 ± 54) μm ( P ＜ 0.05 ).( 2 ) Following transplantation of 1 × 104 cells,only the Bcrp1 + cells formed tumors in NOD/SCID mice.When 1 × 105 or 1 × 106 cells were transplanted,the tumor incidence and the tumor mass were greater in the Bcrp1 + groups than those in the Bcrp1 - groups ( P ＜ 0.05 ).Conclusion Bcrp1 + HeLa cell have the greater capacity of invasive and the tumorigenicity,which may contain cancer stem cells.