Nanotechnology in diagnosis and therapy of gastrointestinal cancer

Table 1 Summary of types of nanodevices and their properties

NP type	Properties	Advantages	Limitations	Ref.
Iron	Imaging: MRI contrast, lymph nodes; antigen/receptor ligand, magnetic targeting; multiple treatment opportunities	Simplicity; low cost; high reproducibility	Adverse events in clinical use: Hypotension, lumbar pain and paresthesia	[63,64]
QDs	Passive and active targeting; imaging through tunable autofluorescence; multiple treatment opportunities	Excellent PLQY; high photostability and biocompatibility; extreme fast synthesis	Toxicity	[65]
Carbon	Passive and active targeting; treatment: Therapeutic cargo delivery; imaging: Visible, infrared	Lightweight, chemically and thermally stable; high tensile strength and conductivity; high resolution and good penetration into the tissue	Adverse events in clinical use: Inflammation, fibrosis	[66]
Gold	Imaging: MRI contrast, fluorescence, optical properties; multiple treatment opportunities	Adjusted optical properties; high biocompatibility	Adverse events in clinical use: Nephrotoxicity	[67]
Polymers	Passive targeting; antigen/receptor ligand targeting; tumor microenvironment-dependent drug release	High thermal stability, biocompatibility; good biodegradability and controlled drug release ability Inhibition of bacterial growth	Toxicity	[69,70]

NP: Nanoparticle; MRI: Magnetic resonance imaging; QDs: Quantum dot; PLQY: Photoluminescent quantum yield.

Table 2 Examples of nanodevices currently under investigation for gastrointestinal cancer

NP type	GI cancer	Application	Ref.
SPION	Colorectal; liver; gastric	Lymph node staging, detection of small metastatic lymph nodes.; magnetic NP-based biosensors for detection of biomarkers; companion diagnostics, evaluate accumulation and predict treatment efficacy of nanomedical cancer therapy	[35,64,71]
QDs	Colorectal; liver; gastric	Cancer targeting and imaging; NIR-QD for simultaneous visualization of SLNs; multicolor QD probes for diagnosis of malignant tumors	[41,72-74]
Carbon nanotubes	Colorectal; liver	Detection of lymph nodes and node metastasis; tumor localization	[49,52]
Gold NPs	Colorectal; liver; gastric; pancreatic; esophageal	Photothermal effect; hyperthermia and cellular destruction; X-ray and CT contrast agents; targeted drug delivery	[75-80]
Dendrimers	Pancreatic; colorectal	Dual targeting imaging; targeted drugs delivery and gene therapy; boron neutron capture therapy.	[60,81,82]
Nanoshell	Gastric	Contrast agents; targeted drugs delivery and gene therapy	[42,77]
Polymers	Colorectal; gastric; pancreatic; esophageal	Controlled drug delivery systems	[83-85]

NIR-QD: Near infrared-quantum dot; SLN: Sentinel lymph node; NP: Nanoparticle; SPION: superparamagnetic iron oxide NP; CT: Computed tomography.