Human NANOG mRNA

Nanog is a factor associated with pluripotency and has been found to play an important role in tumorigenesis and development. To date, the underlying mechanisms of cervical tumorigenesis and development remain to be further elucidated. In this study, Nanog mRNA was synthesized in vitro and transfected into HeLa cells. After mRNA transfection, forced expression of Nanog in HeLa cells significantly enhanced the invasion, migration, resistance to chemotherapeutic drugs, and dedifferentiation of cells. In subcutaneous xenograft experiments, the tumorigenic capacity of these cells was significantly enhanced. Real-time fluorescence quantitative PCR showed that Nanog-induced dedifferentiation was associated with increased expression of endogenous Oct4, Sox2, and FoxD3. In addition, dedifferentiated HeLa cells acquired characteristics associated with cancer stem cells (CSCs), such as pluripotent differentiation ability and expression of CSC markers such as CD133. These data indicate that Nanog is a positive regulator of dedifferentiation in cervical cancer.

Cells transfected with and without Nanog mRNA were cultured in tumor sphere formation medium. After 14 days, the number and size of tumor spheres were analyzed. As shown in Figure 1A, the number of tumor spheres formed by cells transfected with Nanog mRNA was significantly greater than that of control cells. In addition, the size of tumor spheres was significantly increased in cells forced to express Nanog. Immunofluorescence was used to detect the expression of Nanog and CD133 in tumor sphere-forming cells, and it was found that >90% of the cells expressed these two markers simultaneously (Figure 1B). To further confirm the cancer stem cell characteristics of tumor sphere HeLa cells, tumor sphere HeLa cells were further cultured in adipogenic differentiation medium for 15 days and then stained with Oil Red O. Red lipid droplets were observed in differentiated cancer cells (Figure 1C).

Figure 1. The effect of Nanog forced expression on acquiring CSC-like phenotype ability. (Ding Y, et al., 2016)