Table 1.

In vitro and in vivo properties of various putative CSC-like subpopulations identified within RCC of adults

Identification method	Markers			Functional analyses
	CD105	CXCR-4	DNAJB8	SP				Spheres		ALDH
Study	Bussolati et al. [47]	Gassenmaier et al. [56]	Nishizawa et al. [57]	Addla et al. [61]	Oates et al. [65]	Huang et al. [66]	Lu et al. [67]	Zhong et al. [58]	Lichner et al. [59]	Debeb et al. [70]	Wang et al. [71]	Ueda et al. [72]9
MSC markers (excluding CD105) in vitro	+	+	ND	+2	ND	ND	ND	+4	+7	+8	ND	+10
MSC marker CD105 in vitro	+	+/−1	ND	ND	ND	ND	−	+/−5	ND	ND	ND	−
Stemness markers in vitro	+	+	ND	+	+	ND	ND	+	+	+	+	+
CD133 marker in vitro	−	−	ND	+/−3	ND	ND	ND	+6	ND	ND	ND	ND
ALDH activity in vitro	ND	ND	ND	ND	ND	ND	ND	ND	ND	+	+	+
SP in vitro	ND	ND	+	+	+	+	+	+	ND	ND	ND	+
Sphere formation in vitro	+	+	ND	+	ND	ND	ND	+	+	+	ND	+
Clonogenicity in vitro	+	+	ND	+	+	+	+	+	+	+	+	+
Self-renewal in vitro	+	+	ND	+	+	+	ND	+	+	+	+	+
Drug resistance in vitro	ND	+	ND	ND	ND	+	ND	+	ND	ND	ND	+
Radioresistance in vitro	ND	ND	ND	ND	ND	+	+	+	ND	+	ND	+
Tumor initiation (tumorigenicity) in vivo	+	+	+	ND	ND	+	+	+	+	+	+	+
Recapitulation of a tumor of origin (phenocopy) in vivo	+	+	ND	ND	ND	+	ND	+	+	+	+	ND
Generation of serially transplantable tumors in vivo	+	ND	ND	ND	ND	+	ND	ND	ND	+	ND	ND
Endothelial differentiation in vitro and/or in vivo (multipotency) / VM	+	ND	ND	ND	ND	ND	ND	ND	+	ND	ND	ND

ND not determined

¹A major subpopulation within CXCR-4⁺ sphere cells derived only from established cell line SK-RC-17, not from primary cell lines

²The CD44 and CD29 MSC markers (however, no significant difference compared to non-SP cells)

³Significantly higher cell number in SP than in non-SP cells, however, lower cell number than in the SP of the normal kidney

⁴The CD44 MSC marker, along with CD24 (however, no significant difference compared to non-sphere cells)

⁵Expressed on nearly all non-sphere cells, however, significantly reduced expression on sphere-forming cells

⁶No significant difference compared to non-sphere cells

⁷The CD44 MSC marker, along with CD24

⁸The CD44 MSC marker

⁹Significantly higher ALDH activity in SP than in non-SP cells only in the case of ACHN cell line (ALDH⁺ SP ACHN CSCs)

¹⁰The CD90 MSC marker (however, no significant difference compared to non-SP cells)