Mesenchymal stem cells in preclinical cancer cytotherapy: a systematic review

Table 1 Summary table of main experimental parameters and outcome as determined by the meta-analysis of cancer cytotherapy studies using naïve (unmodified) MSC

Consolidated groups	N	MSC	MSC N	Tumors most frequently targeted (%)	Tumor target frequency (%)	Mean antitumor effect*
In vivo (naïve)	30	AT	5	Brain/neural	60	ND
		BM	20	Breast	25	ND
		BM		Colorectal	25	ND
		UC	5	Breast	40	ND
In vitro (naïve)	53	AT	10	Breast	30	ND
		BM	22	Breast	32	??
		UC	21	Breast	33	ANTI-
In vitro + in vivo (naïve)	83	AT	15	Brain/Neural	40	??
		BM	42	Breast	29	PRO+
		BM		Colorectal	19	PRO+
		UC	26	Breast	31	ANTI-
In vitro + in vivo x(naïve+naïve as CTRL for GM)	126	AT	31	Brain/Neural	32	ANTI-/NEUTRAL
		BM	59	Breast	24	PRO+
				Colorectal	15	PRO+
				Liver	12	??
		UC	36	Breast	33	ANTI-
		UC		Lung	17	ANTI-

Findings based both on studies focusing solely on naïve MSC, as well as on selected studies where these cells were used as controls for experiments focusing on genetically modified MSC (GM-MSC) are shown. Results are listed in consolidated groups of increasing size (number of observations = N). MSC N column depicts MSC sample size. Primary outcomes include percentage of the most frequently targeted tumor types by the respective MSC, as well the mean anti-cancer effect for each MSC (effector): tumor combination. The minimum accepted number of MSC (cut-off) most commonly associated with respective tumors was set to six
*PRO+ denotes tumor-promoting effect exerted by >50% of the associated MSC
ANTI denotes inhibition of tumor by >50% of the associated MSC
?? denotes no clear effect
ND not determined due to insufficient data (N < cut-off)

ISSN: 1757-6512