Conclusion
Tumourigenic characteristics of ECCs may provide a valuable insight into possible tumour progression of HESCs.
Methods
SSEA-3 positive ECCs (NTERA-2) cells were identified and compared to HESCs (ch HES-20) in terms of pluripotency and differentiation capacity, growth characteristics, gene expression profiles and signalling pathways.
Results
Our results showed that NTERA-2 cells shared similarities in expression markers of pluripotency to ch HES-20 cells. However, NTERA-2 cells also expressed some markers of differentiation and had a tendency to differentiate towards ectodermal endpoints. We identified NTERA-2 cells with higher S-phase fraction in cell cycle distribution, anti-apoptosis markers and robust self-renewal ability, compared to ch HES-20 cells. Microarray analysis and real-time PCR results showed that some oncogenes were up-regulated and tumour-suppression genes were down-regulated, whereas pluripotency-related genes were up-regulated and differentiation-related genes were down-regulated, and that Wnt and Notch signalling pathways were activated during progression from ES cells to EC cells.