Extended data figure 8. Breast TICs express Snail.

(a) H&E staining showing the histology of the donor primary tumour where cells used in Fig. 3f were isolated from, scale bar 200 μm. (b) The original pulmonary metastases spawned by the primary tumour (left panel), and pulmonary metastases formed by the indicated tumour cell populations following tail-vein injection, scale bar 500 μm. (c) Higher magnification images of H&E stained lung sections showing histology of the original pulmonary metastases in the donor animal (left panel), and pulmonary metastases formed by the Slug-YFP^loEpCAM^lo tumour cells following tail-vein injection. Scale bar 200 μm. (d) Representative immunofluorescence staining image of sections of pulmonary metastases formed by the Slug-YFP^loEpCAM^lo tumour cells were stained for DAPI (blue), Slug (green), CK14 (red), and CK8 (grey). Arrowheads indicate Slug-positive cells. Scale bar 20 μm. Images represent four independent experiments. (e) H&E staining of the donor primary tumour where cells used in Fig. 3g were isolated from (left panel) and H&E staining of primary tumours formed by the indicated populations following subcutaneous implantation (with 25% Matrigel). (f) Primary tumour burdens formed by the indicated populations following subcutaneous implantation (For EpCAM^loSlug^lo cells 1^10⁴ cells were injected, for the other two groups 1^10⁵ cells were injected. Primary tumours and lungs were analyzed 10-weeks post injection. n=10 sites of injections for each group). Open circle indicates failure of tumour-initiation. Scale bar 200 μm. Source Data are enclosed in Source Data T3. (g) H&E staining of lung sections showing metastatic outgrowths spawned by the indicated cell populations following subcutaneous implantation. Scale bar 500 μm.