Noninvasive in vivo cell tracking using molecular imaging: A useful tool for developing mesenchymal stem cell-based cancer treatment

Table 1 Noninvasive in vivo imaging of mesenchymal stem cells in treatment and drug delivery for cancer

Imaging	Imaging modality	Labelingmethod/agent	Cell type	Naïve/modified	Cell origin	Subject	Route of injection	Duration	Tumor	Outcome	Clinical translation	Ref.
Optical	Fluorescent	FNPs	BM-MSCs	AlPcS4@FNPs@MSCs	Human	Mice	Intratumor	Immediately	Human osteosarcoma	Inhibition of tumor	Limited	Lenna et al[81]
		EGFP	BM-MSCs	TRAIL-MSCs	Mouse	Mice	Intravenous	1-10 d	Mouse colon cancer	Inhibition of tumor	Limited	Zhang et al[82]
		VivoTrack 680	BM-MSCs	MSCs	Human	Mice	Intravenous	2-24 h	Breast cancer	Inhibition of tumor metastasis	Limited	Camorani et al[83]
	Bioluminescent	Rluc	UC-MSCs	HSV-ttk-MSCs	Human	Mice	Intratumor	1-4 d	Breast cancer	Inhibition of tumor	Limited	Leng et al[84]
		Fluc	BM-MSCs	MSC-Tet-TK/ MSC-TK	Mouse	Mice	Intratumor	1 and 5 d	Mouse colon cancer	Inhibition of tumor	Limited	Kalimuthu et al[85]
		Fluc	BM-MSCs	MSC-CXCR4	Mouse	Mice	Intravenous	1 and 24 h	Breast cancer	Homing of genetically modified MSCs to tumor	Limited	Kalimuthu et al[86]
		Fluc	BM-MSCs	Naïve	Human	Mice	Intravenous	5 to 8 wk	Breast cancer	Homing of MSCs to lung metastatic tumor	Limited	Meleshina et al[87]
		Fluc	BM-MSCs	Naïve	Human	Mice	Intravenous	1 and 24 h	Thyroid and breast cancer	In vitro Dox delivery/homing of MSCs to tumor	Limited	Kalimuthu et al[88]
		Fluc	BM-MSCs	Naïve	Mouse	Mice	Intravenous	1-11 d	Murine breast cancer	Homing and differentiation of MSCs to tumor	Limited	Wang et al[89]
		Fluc	BM-MSCs	MSCs-oncolytic adenovirus	Human	Mice	Intravenous	15 min to 10 d	Murine large cell lung carcinoma	Homing of MSCs to tumor	Limited	Hakkarainen et al[90]
		Rluc	BM-MSCs	MSC-e23sFv-Fdt-tBid	Mouse	Mice	Intravenous	24 h	Breast cancer and gastric cancer	Inhibition of tumor	Limited	Cai et al[91]
Nuclear	PET	[18F]-FHBG	BM-MSCs	MSC-HSV1-TK	Human	Mice	Subcutaneous	4 wk	Murine colon carcinoma	MSCs stably stay in tumor	Yes	Hung et al[60]
		124I	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	72 h	Human hepatocellular carcinoma	Inhibition of tumor	Yes	Knoop et al[92]
		124I	BM-MSCs	MSC-hNIS	Mouse	Mice	Intravenous	72 h	Mouse pancreatic tumor	Inhibition of tumor	Yes	Schug et al[93]
	γ-camera	123I	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	72 h	Human hepatocellular carcinoma	Inhibition of tumor	Yes	Knoop et al[92]
		123I	BM-MSCs	HSP70B-NIS-MSC	Human	Mice	Intravenous	0-72 h	Human hepatocellular carcinoma	Inhibition of tumor	Yes	Tutter et al[94]
		123I	BM-MSCs	MSC-hNIS	Mouse	Mice	Intravenous	72 h	Mouse pancreatic tumor	Inhibition of tumor	Yes	Schug et al[93]
		123I	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	72 h	Human hepatocellular carcinoma	Inhibition of tumor	Yes	Schug et al[95]
		99mTc	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	3-14 d	Breast cancer	Inhibition of tumor	Yes	Dwyer et al[64]
		99mTc	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	3-24 d	Human cervical cancer	Inhibition of tumor	Yes	Belmar-Lopez et al[96]
MR	MRI	SPIO	BM-MSCs	MSC-hNIS	Human	Mice	Intravenous	3-24 d	Human cervical cancer	Inhibition of tumor	Yes	Belmar-Lopez et al[96]
		SPIO@Au-NPs	BM-MSCs	MSC	Human	Mice	Intravenous	0-72 h	Human glioma	Homing of MSC to tumor	Yes	Qiao et al[97]

FLI: Fluorescence imaging; BLI: Bioluminescence imaging; MRI: Magnetic resonance imaging; PET: Positron-emission tomography; γ-camera: Gamma camera imaging; FNPs: Fluorescent nanoparticles; EGFP: Enhanced green fluorescent protein; Fluc: Firefly luciferase; Rluc: Renilla luciferase; SPIO: Superparamagnetic iron oxide; TRAIL: Tumor necrosis factor-related apoptosis-inducing ligand; HSV1-tk: Herpes simplex virus type 1 thymidine kinase; hNIS: Human sodium iodide symporter; Au-NPs: Gold nanoparticles; HSP70B: Heat-inducible promoter; PDGFRβ: Platelet-derived growth factor receptor β; CXCR4: CXC chemokine receptor type 4.