Selecting the optimal parameters for sonoporation of pancreatic cancer in a pre-clinical model

Figures & data

Figure 1. Effects of Sonoporation: At lower power the sonoporation can cause ruptures in cell membranes, increasing the permeability of individual cells. As power increases sonoporation can cause gaps between and through cells causing pooling of blood and an increased permeabilization of a regional area to drug, this is the modality of interest. As power continues to increase sonoporation can cause the rupture of the ultrasound contrast agents which can completely disrupt blood supply in a specific region

Table 1. Comparison of ultrasound contrast agents

Ultrasound Contrast Agent	Casing	Gas	Diameter (µm)	Zeta Potential (mV)	Manufacturer
Definity	Phospholipid	Octafluoropropane	1.1-3.3	-4.2	Lantheus Medical Imaging
Optison	Protein-Type A	Perflutren	3.0-4.5	-9.5	GE Healthcare
Lumason/Sonovue	Phospholipid	Sulphur hexafluoride	2.5	-28.3	Bracco Diagnostics
Sonazoid	Lipid	Perflurobutane	2.6	-82	GE Healthcare

Comparison of basic characteristics including casing, gas, size, charge and manufacturer of the ultrasound contrast agents investigated

Figure 2. Tumor growth for IV treated mice: A,B) Comparison of all treatment arms across low and high ultrasound power respectively C-F) Comparison of total tumor volume for ultrasound alone vs individual ultrasound contrast agents (SonoVue + drug + US, Sonazoid+ drug + US, Optison+ drug + US and Definity+ drug + US, respectively) against chemotherapy split by high and low ultrasound power settings

Figure 3. Tumor vascularity for IV treated mice: A-B) Comparison of all treatment groups as broken down by low and high ultrasound power by tumor vasculature % fold change

Figure 4. Tumor volumes of IP treated mice: A) Tumor volumes of all mice normalized as percentage difference in fold change to the chemotherapy treated control B)Comparison of high vs low ultrasound power differences against chemotherapy C-F) Comparison of individual ultrasound contrast agents (SonoVue+ drug + US, Sonazoid+ drug + US, Optison+ drug + US and Definity+ drug + US, respectively) against chemotherapy split by high and low ultrasound power settings

Figure 5. Measures of tumor vascularity: A-E) Comparison of vehicle and individual ultrasound contrast agents against chemotherapy % total O₂ in tumors split by high power settings F) Comparison of tumor oxygenation at baseline prior to sonoporation with Sonazoid in the high acoustic power cohort and after sonoporation treatment has been completed (4 weeks later just prior to sacking). This image depicts an overall increase in oxygenation from 49% to 53% within the imaging plane (and from 41% to 54% within the entire tumor volume of this animal). G) Tumors were stained with CD31 (red) staining epithelial cells, and counterstained with tomato lectin (green indicating endothelial cells) and DAPI staining (blue demonstrating cellularity)

Table 2. Overall comparisons

	Treatment	Sonovue		Sonazoid		Optison		Definity
	Ultrasound Power	low	high	low	high	low	high	low	high
IP	Tumor Volume (vs chemo)	*	****	◌	**	○	****	***	***
	Hemoglobin total (vs chemo)	N/A	○	N/A	◌	N/A	○	N/A	○
	Hemoglobin Average (vs chemo)	N/A	○	N/A	○	N/A	○	N/A	○
	SO2 total (vs chemo)	N/A	◌	N/A	*	N/A	○	N/A	○
	SO2 average (vs chemo)	N/A	○	N/A	◌	N/A	○	N/A	*
	Increase in Tomato Lectin Staining	○	○	●	●	●	●	●	●
IV	Tumor Volume vs Chemo	○	○	*	***	○	*	○	○
	% Vasculature vs Chemo	○	○	**	**	○	◌	○	*

Summary of all changes observed sonoporations treatments vs treatments across high and low ultrasound power and both IP and IV treatment groups including the following parameters: tumor volume, hemoglobin total, hemoglobin average, SO2 total, SO2 average, Tomato Lectin staining and % vasculature. The following symbols for this table N/A, ◌, *, **, ***, ****, ●, ○ indicate p < .15, <.05, <.01, <.005, <.001, qualitative change and no change respectively