Transplanted pTD cells are more tumorigenic in vivo than parental CDβGeo cells. (A) Survival curve for mammary tumour incidence in weeks. pTD cell transplants are significantly more tumorigenic than CDβGeo cells (p < 0.01). (B) Immunohistochemistry for CDβGeo normal-like ductal outgrowth (first column), hyperplastic outgrowth (second column), acinar adinocarcinoma (third column) and pTD tumours (fourth column): hematoxylin and eosin stain (first row); ERα expression (second row); immunofluorescence for K8 (third row); K5 (fourth row); Dapi (fifth row) and merge (sixth row). Scale bar = 20 μm.