Table 2

Marker	Target	Cell numbers required for tumour formation in vivo	Reference
CD44⁺/CD24^-/ESA⁺	Human breast cancers: Basal-like, claudin low, Her2-ve, BRCA null, and medullary tumours	200	[4,18]
CD44⁺/CD24^-/ESA⁺	Cell lines	Not tested	[17]
CD44⁺/CD49f^hi/CD133⁺	ERα^- tumours	250	[19]
CD49f⁺	MCF-7 cell line	Not tested	[21]
CD133⁺	BRCA^- mouse tumours	50	[23]
ALDH⁺	Human breast cancers: Triple negative ERBB2 negative	500	[24]
ALDH⁺	Cell lines e.g. SUM159	100	[26]
CD44⁺/CD24^-/ESA⁺ ALDH⁺	Human breast cancers	20	[24]
PROCR⁺/ESA⁺	MDA-MB-231 cell line	100	[17]

Table 2: Markers used to isolate breast cancer cell subpopulations enriched for tumorigenic capacity.