Table 2.

Summary of preclinical studies of UMGT for cancer immunotherapy.

UMGT Approaches	Tumor models	Gene constructs	Ultrasound parameters	Target cell	Ref.
5.1 Transfection with ultrasound	Fibrosarcoma, murine models	GM-CSF pDNA	f = 1 MHz, ISATA = 1.0 W/cm2, Duty cycle = 20%, t = 5 min	Tumor cells	[159]
	Melanoma and renal carcinoma murine models	IL-12 pDNA	f = 200 kHz (laboratory lithotripter similar to Dornier HM-3 lithotripter), PNP = 7.4 MPa, PRF = 2 Hz, Shock Waves = 500 (Duty cycle: 0.5%) + intratumoral air bubbles	Tumor cells	[160]
5.2 MB-based transfection	Prostate cancer murine models, human prostate tumor xenografts	IL-27 pDNA	f = 1 MHz, PNP = 0.12 MPa, ISATA = 1 W/cm2, PRF = 2 Hz, Duty cycle = 50%, t = 2 min, + SonoVue MBs	Tumor cells	[161]
	Melanoma murine models	IFN-β pDNA	f = 1.011 MHz, ISATA = 0.22 W/cm2, Duty cycle = 50%, PRF = 0.5 Hz, t = 3 min, + Sonazoid MBs	Tumor cells	[162]
	Cervical cancer murine models	miR-34a	f = 1 MHz, I = 1.5 W/cm2, Duty cycle = 50%, t = 90 s, + cationic lipid MBs	Tumor cells	[163]
	Breast cancer, murine models	IFN-β pDNA	f = 250 kHz, PNP = 500 kPa, ISPTA = 1 W/cm2, PRF = 30 Hz, t = 3 min, Duty Cycle = 12%, + anti-EpCAM conjugated MBs	Stromal cells, tumor cells	[21]
5.3 Ultrasound-responsive delivery system	Ovarian carcinoma, murine models	IL-12 pDNA	f = 1 MHz, I = 0.7 W/cm2, t = 60 s, + liposomal bubbles	Cells in TME	[164]
	Lymphoma murine models	OVA pDNA	f = 2.062 MHz, I = 4 W/cm2, Duty cycle = 50%, t = 20 s, +mannose-modified liposomes	APCs	[165]
	Melanoma murine models	pUb-M cDNA	Duty cycle = 50%, PRF = 10 Hz, t = 2 min, +mannose-modified liposomes f = 1.045 MHz, I = 1 W/cm2 (for intravenous injection) f = 2.062 MHz, I = 4 W/cm2 (for intradermal and intrasplenic injection)	APCs	[166]
5.4 Modulation of immune cell functionality	Lymphoma and leukemia cell models	Anti-CD19 CAR gene loaded lentiviruses	f = 2 MHz, ISPTA = 0.6 W/cm2, PNP = 0.6 MPa, PRF = 5 Hz, Duty cycle = 5%, t = 10 min, +MBs	Jurkat T cells and PBMCs	[167]
	Lymphoma and prostate cancer models	Cre-lox gene with HSP promotor	f = 1.5 MHz	T cells	[168]
	DCs from bone marrow of C57Bl/6 mice	mRNA encoding luciferase or GFP	f = 1 MHz, I = 2 W/cm2, Duty cycle = 50% t = 30 s, + lipoplexes + MBs	DCs	[169]
	Melanoma lung metastasis murine models	Antigen mRNA and TriMix mRNA	f = 1 MHz, ISPTA = 2 W/cm2, PNP = 800 kPa, Duty cycle = 20%, PRF = 100 Hz, t = 30 s, lipid MBs	DCs	[170]
	Hepatocellular carcinoma human cells	Foxp3 siRNA	f = 2.5 MHz, MI = 1.4, t = 150 s, + SonoVue MBs	Tregs	[171]

Abbreviation: f: frequency, I: acoustic intensity (this notation is used when the specific intensity metric cannot be determined), PNP: peak negative pressure, PRF: pulse repetition frequency, MI: mechanical index, EpCAM: Epithelial cell adhesion molecule, IFN-β: Interferon-beta, IL-27: interleukin 27, IL-12: interleukin 12, GM-CSF: granulocyte-macrophage colony-stimulating factor, OVA: ovalbumin, HSP: heat shock protein, Foxp3: Forkhead box P3, APC: antigen-presenting cells, DCs: dendritic cells, PMBCs: peripheral blood mononuclear cells, I_SPTA: Spatial peak temporal average intensity, I_SATA: Spatial average temporal average intensity