Objective       To determine the role of the stem cell marker

Nanog

in the self-renewal and metastasis of colorectal cancer cells.       Methods        The constructed Nanog lentiviral vector Lv-pNanog-GFP that carrying green fluorescent protein (GFP) was used to infect human colorectal cancer cell line HCT116

and the cells with positive and negative expression of GFP were sorte

d by flow cytometry. Western blotting was employed to detect the effectiveness of the virus infection. Clone formation and sphere formation were applied to determine self-renewal capacity. Metastatic ability of tumor cells were detected by Transwell assay.       Results       After 12 h of the cells infected with the virus

inverted fluorescence microscopy indicated that the expression of GFP fluorescence

suggesting that the virus Lv-pNanog-GFP stably infected HCT116 cells

with a GFP positive rate of 5.9%. Western blotting results showed that GFP sorting the cells expressed exactly the amount of corresponding Nanog. Clone formation rate of Nanog positive cells [(56.3±2.87)%

]

was significantly higher than that of Nanog negative cells [(19±2.16)%

P

0.05

]

. Sphere volume of Nanog positive cells was increased significantly and the sphere formation rate [(34±4)%

]

was significantly greater than Nanog negative cells [(10.67±6.43)%

P

0.05

]

. We demonstrated that Nanog positive cells exhibited enhanced ability of self-renewal. The number of Nanog positive cells through the Transwell cells (175.8±12.89) was significantly larger than that of Nanog negative cells (74.6±16.55

P

0.05). Nanog positive cells exhibited enhanced ability of metastasis.       Conclusion       Nanog regulates self-renewal and metastasis in colorectal cancer cells.