Figure 2. Identification of tumour-propagating cells in sebaceous tumours.

(a) Transplantation assay of tumour cells into nude mice. (b) Engraftment of limiting dilutions of tumour cells. (c) Tumour size following transplantation of limiting dilutions and serial transplantations of sebaceous tumour cells. (d–g) hematoxylin and eosin (HE) (d,f) and immunofluorescent staining (e,g) for SCD1 (green) of original tumour of K14ΔNLef1 mice (d,e) and tumour developing following 2nd transplantation (f,g; n=6). Nuclei (red) stained with propidium iodide, (PI). (h,i) Tumour development and size in transplants of FAC-sorted Itga6^high cells (h) and CD34⁺/Itga6^high (i) compared with whole tumour cell population (h) and CD34⁻/Itga6^high fraction (i; Itga6^high n=6). (j) Colony-forming assay performed with CD34⁺/Itga6^high and CD34⁻/Itga6^high sorted tumour cells isolated from K14ΔNLef1 mice (n=3 mice, assay in triplicates). Scale bars, 50 μm.