Objectives: The objective of this study was to compare tumourigenic characteristics of human embryonic stem cells (HESCs) and embryonal carcinoma cells (ECCs) to identify a robust and simple model for studying certain aspects of cell transformation and tumourigenesis, in tumour progression of HESCs.
Materials and 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.
Conclusion: Tumourigenic characteristics of ECCs may provide a valuable insight into possible tumour progression of HESCs.
© 2012 Blackwell Publishing Ltd.