Figure 3.

In vitro and in vivo experimental models available to study cancer stem cells. (A) In vitro systems include standard cultures of adherent bulk tumor cells and tumor-sphere cultures of cancer stem cell (CSC)-enriched subpopulation capable of self-renewal. (B) Mouse xenograft models allow the isolation of CSC and monitoring self-renewal and tumorigenicity in ex vivo tumor-sphere assays and in vivo serial re-implantation assays. (C) Tumor-sphere assays and in vivo serial re-implantation can be performed with genetically engineered mouse (GEM) models through the isolation and propagation of CSC-enriched tumor-spheroids.