. 2013 Mar 29;22(16):2221–2239. doi: 10.1089/scd.2012.0613

Table 1.

Strategies for the Isolation and Enrichment of Different Types of CSCs

Strategy	Tumor type	Positive ratio (%) or fold enriching	CSC frequency (1:X) or tumorigenicity	Refs.
Surface markers
CD34⁺CD38⁻	Leukemia	0.02%–2.00%	1:5,000	[8,9]
CD44⁺CD24^−/lo	Breast cancer	1.32%–5.00%	50 cells implanted, tumors detected in 4/7 mice	[11]
ESA⁺CD44⁺CD24^−/loLin⁻		0.60%	1:100	[10]
CD133⁺		2.00%–5.90%	50 cells implanted, tumors detected in 4/7 mice	[11]
CD49f⁺DLL1^hiDNER^hi		Unknown	1:48,249–1:97,134, well-differentiated tumor	[13]
			1:15,708–1:30,840, poorly differentiated tumor
Thy1⁺CD24⁺CD45⁻		1.00%–4.00%	1:213	[14]
CD44⁺CD49f^hiCD133/2^hi		0.50%–2.00%	250 cells implanted, tumors detected in 2/5 mice	[15]
			250 cells implanted, tumors detected in 7/10 mice
			250 cells implanted, tumors detected in 3/5 mice
			50 cells implanted, tumors detected in 3/6 mice
			50 cells implanted, tumors detected in 3/6 mice
CD133⁺	Colon cancer	3.20%–24.50%	1:262	[29]
EpCAM^hi/CD44⁺		0.03%–38.00%	200 cells implanted, tumors detected in 5/10 mice	[31]
		0.80%–38.00%	Unknown
EpCAM^hi/CD166⁺		1.20%–16.00%	Unknown
ESA^hi/CD166⁺		Unknown	4,000 cells implanted, tumors detected in 3/5 mice
ESA^hi/CD44⁺		Unknown	2,000 cells implanted, tumors detected in 17/19 mice
ESA^hi/CD44⁺/CD166⁺		Unknown	150 cells implanted, tumors detected in 1/2 mice
LGR5⁺		5.00%–10.00%	Unknown	[32]
CD47⁺	Leukemia	Unknown	Unknown	[33]
	Beast cancer	∼3.3-fold increase	1×10⁵ cells implanted, tumorigenicity unknown	[34]
	Colon cancer		3.8×10⁴ cells implanted, tumorigenicity unknown
	Bladder cancer		2,000 cells implanted, tumorigenicity unknown
	Head & neck cancer		1×10⁵ cells implanted, tumorigenicity unknown
	Ovarian cancer		2.2×10⁴ cells implanted, tumorigenicity unknown
	Glioblastoma		1×10⁵ cells implanted, tumorigenicity unknown
Cripto-1⁺	Embryonal cancer	30.20%–60.60%	Unknown	[52]
CD44⁺CD133⁺	Gallbladder cancer	40.29%	10⁴ cells implanted, tumors detected in 4/4 mice, primary sample	[51]
			10⁴ cells implanted, tumors detected in 5/5 mice, cell line
CD44⁺	Gastric cancer	0%–94.00%	<1:33	[25]
CD133⁺	Brain tumor	19.00%–29.00%	1:100, glioma	[16]
		6.00%–21.00%	1:100, medulloblastoma
SSEA-1⁺		26.60%	1,000 cells implanted, tumors detected in 7/7 mice	[17]
CD15⁺		34.00%	10⁴ cells implanted, tumors detected in 5/6 mice	[18]
A2B5⁺		Unknown	5×10⁵ cells implanted, tumors detected in 7/8 mice	[19]
		61.70%	1×10⁴ cells implanted, tumors detected in 3/4 mice	[20]
EGFR		4.00%–35.20%	Unknown	[21]
CD44⁺	Head and neck cancer	5.47%–10.40%	5,000 cells implanted, tumors detected in 6/7 mice	[24]
		53.00%	1,000 cells implanted, tumors detected in 6/8 mice	[59]
CD133⁺	Liver cancer	0.05%–46.79%	1×10⁷ cells implanted, tumors detected in 4/4 mice	[45]
		0.10%–1.00%	100 cells implanted, tumors detected in 3/6 mice	[46]
			1,000 cells implanted, tumors detected in 4/6 mice
CD90⁺		0%–90.00%	1,000 cells implanted, tumors detected in 2/2 mice	[47]
CD13⁺		1.64%	100 cells implanted, tumors detected in 2/4 mice	[48]
CD166⁺	Intestinal cancer	8.10%	100 cells implanted, tumors detected in 2/4 mice	[26]
Sca-1⁺CD45⁻PECAM^-CD34⁺	Lung cancer	2.00%–16.00%	100 cells implanted, tumors detected in 2/4 mice	[35]
CD133⁺		0.32%–22.00%	Unknown	[36]
CD133⁺ABCG2⁺		6.05%–14.50%	Unknown	[37]
		15.00–25.00%	1:1×10⁴
CD133⁺CXCR4⁺		3.50%–7.50%	Unknown
CD133⁺ESA⁺		0.02%–35.00%	Unknown
CD133⁺		0.02%–36.00%	Unknown
CD133⁺CD44⁺		0.90%	Unknown	[38]
CD166⁺		Unknown	1:5,175	[39]
CD20⁺	Melanoma	0.92%	Unknown, WM3539 cells	[40]
		Unknown	Unknown, WM3523 cells
ABCB5⁺		1.60%–20.40%	1:5,175	[41]
CD271⁺		2.50%–41.00%	Unknown	[42]
ABCG2⁺CD133⁺		1.00%	1:5,000	[43]
CD133⁺	Osteosarcoma	3.00%–5.00%	Unknown	[49]
CD133⁺CXCR4⁺		0.50%–80.00%	100 cells implanted, tumors detected in 6/12 mice	[23]
CD44⁺CD24⁺ESA⁺	Pancreatic cancer	0.20%–0.80%	Unknown	[27]
CD133⁺		1.09%–3.21%	Unknown	[28]
Suspension culture
CD15⁺ cells	Medulloblastoma	Unknown	1×10⁴ cells implanted, tumors detected in 5/6 mice	[18]
ALDH1⁺ cells	Esophageal cancer	28.60%	Unknown	[67]
CD117⁺Stro-1⁺ cells	Osteosarcoma	6.00%–14.00%	200 cells implanted, tumors detected in 2/4 mice, K7M2 cells	[50]
			200 cells implanted, tumors detected in 2/5 mice, 318-1 cells
Activity of intracellular enzymes
ALDH1⁺ cells	Head and neck cancer	1.00%	250 cells implanted, tumors detected in 6/7 mice	[85]
	Lung cancer	0.60%–2.90%	1:1,000	[82]
	Breast cancer	3.00%–10.00%	5,000 cells implanted, tumors detected in 3/4 mice	[73]
	Melanoma	Unknown	1:4	[94]
26S proteasome	Glioma	<4.00%	100 cells implanted, tumors detected in 1/4 mice	[87]
	Breast cancer		Unknown
Concentration of ROS	Lung cancer	Unknown	Unknown	[105]
		Unknown	Unknown	[115]
	Breast cancer	Unknown	100–1,000 cells implanted, tumors detected in 5/7 mice	[104]
Mitochondrial membrane potential	Glioma	Unknown	Unknown	[116]
Promoter-driven system
c-Myc-Ras-IκBα system	Breast cancer	26.00%	1:2,200	[117]
LvP_Nanog-GFP system	Liver cancer	2.40%–47.40%	1 cell implanted, tumors detected in 2/6 mice	[128]
Autofluorescence	Glioma	0.50%–3.20%	1:1,000	[132]
Adherent culture
CD133⁺ cells	Head and neck cancer	0.10%–0.18%	Unknown	[135]
CD44⁺ cells		2.90%–12.30%	Unknown
CD29⁺ cells		8.10%–17.80%	Unknown
CD44⁺CD133⁺ cells		0.10%	Unknown
CD44⁺CD29⁺ cells		0.80%–3.60%	Unknown
Sca-1⁺ cells	Breast cancer	44.00%–6.97%	1:865, 4T1 cells	[137]
			1:11,867, 66cl4 cells
CD133⁺ cells	Melanoma	0.03%–4.30%	1:781, B16-F1 cells
ALDH1⁺ cells		12.30%–28.80%	1:4,027, B16-F1 cells
			1:7,531, B16-F10 cells
			1:13,567, Ret cells
	Adenocarcinoma	0.03%–2.62%	Unknown	[153]
	Breast cancer	0.20%	1,000 cells implanted, tumors detected in 1/6 mice	[148]
	Colon cancer	3.10%–17.00%	100 cells implanted, tumors detected in 3/5 mice	[152]
	Hematopoietic tumor	0.10%	Unknown	[143]
	Lung cancer	1.50%–6.10%	1,000 cells implanted, tumors detected in 2/4 mice	[145]
		0.10%–4.00%	50 cells implanted, tumors detected in 6/8 mice	[156]
	Nasopharyngeal cancer	0.10%–6.80%	1×10⁴ cells implanted, tumors detected in 3/3 mice	[146]
	Gastric cancer	1.29%–1.69%	Unknown, Caco2 cells	[152]
		0.08%	1,000 cells implanted, tumors detected in 1/3 mice, MKN-45 cell	[154]
		0.18%	5×10⁴ cells implanted, tumors detected in 1/3 mice, BGC-823 cell
	Glioma	0.40%	Unknown	[147]
		0.04%–0.10%	1,000 cells implanted, tumors detected in 1/1 mouse	[148]
		12.00%	1:1×10⁴	[186]
	Neuroblastoma	4.00%–37.00%	Unknown	[149]
	Ovarian cancer	0.05%	Unknown	[148]
		0.10%–1.70%	1:500	[151]
	Osteosarcoma	3.70%–10.20%	500 cells implanted, tumors detected in 3/9 mice	[118]
	Glioma	0.04%–0.10%	100 cells implanted, tumors detected in 7/11 mice, U373 cells	[148]
	Breast cancer	0–0.20	1,000 cells implanted, tumors detected in 1/6 mice, MCF7 cells
	Ovarian cancer	0.05%	Unknown
	Prostate cancer	0.07%	100 cell implanted, tumors detected in 2/8 mice, LAPC-9 cells
Cell division	Breast cancer	0.20%–0.40%	1:26	[13]
		Unknown	1:2	[159]
	Ovarian cancer	7.00%	Unknown	[160]
	Gastrointestinal cancer	20.00%–30.00%	Unknown	[161]
		1.90%–2.70%	10 cells implanted, tumors detected in 14/20 mice	[162]
	Nasopharyngeal cancer	0.60%	Unknown	[163]
	Glioma	5.00%	1:2×10⁵	[165]
	Liver cancer	0.70%	100 cells implanted, tumors detected in 2/4 mice	[166]
Cytotoxic and hypoxic resistance
CD133⁺ cells	Glioma	2–10-fold increase	1:1,000–5,000, IR treatment	[5]
		45.40%	Unknown, hypoxia selected	[182]
		37.00%	Unknown, rotenone treatement
ABCG2⁺ cells		30.00%	Unknown, mitoxatrone treatement	[186]
ALDH1⁺ cells	Esophageal cancer	5.60%	Unknown, cisplatin treatment	[67]
ALDH1⁺ cells	Breast cancer	5.60%	Unknown, ADR treatment	[188]
CD44⁺CD24⁻ cells		32.40%	5,000 cells implanted, tumors detected in 1/2 mice, estrogen treatment
ALDH1⁺ cells		2–4.8-fold increase	Unknown, sunitinib treatment, MDA-MB-231 cells	[193]
		4.6-fold increase	Unknown, sunitinib treatment, SUM159 cells
		2-fold increase	Unknown, bevacizumab treatment, MDA-MB-231 cells
		2–3-fold increase	Unknown, hypoxia selected, SUM159 cells
CD44⁺CD24^-ESA⁺ cells		3-fold increase	500 cells implanted, tumors detected in 4/5 mice, hypoxia selected, MDA-MB 231 cells	[194]
		12-fold increase	500 cells implanted, tumors detected in 4/5 mice, hypoxia selected, BCM2 F3 cells
CD44⁺CD24⁺ESA⁺ cells	Pancreatic cancer	1.30%	5×10⁵ cells implanted, tumors detected in 8/8 mice, gemcitabine treatment	[181]
SP cells	Oral cancer	20.80%	Unknown, 5-FU treatment	[179]
		28.00%	Unknown, CBDCA treatment
		12.60%	Unknown, 5-FU+CBDCA treatment
SP cells	Osteosarcoma	0.11%	5×10⁶ cells implanted, tumors detected in all mice, U2OS cells, MTX treatment	[185]
CD177⁺Stro-1⁺ cells		0.60%
ABCG2⁺ cells		23.15%	Unknown, MG-63 cells, 3AB treatment	[187]
Invasiveness and adhesion
Direct selection	Glioma	0.79%–41.02%	Unknown	[204]
	Pancreatic cancer	1.96%–47.20%	1:500	[28]
TGF β treatment	Colon cancer	CD44 2.65%	Unknown	[201]
		Sox2 5.25%
		Sca-1 1.90%
		CD24 1.90%
FOXC2 treatment	Breast cancer	Unknown	1:1,000	[202]
Snail treatment	Colon cancer	CD44 4–17-fold increase	Unknown	[203]
		CD133 2–3-fold increase
Immunoselection	Breast cancer	11.00%–23.50%	Unknown	[206]
Density gradient centrifugation	Liver cancer	4.73%	1×10⁴ cells implanted, tumors detected in 1/6 mice	[212]