Fig 1.
Correlation analysis between different methods for tumor volume assessment.
Nonlinear regression of data points collected from orthotopic subcutaneous tumors (n = 10 animals). The correlation coefficient R squared is provided in the lower right hand of each graph.
Fig 2.
In vivo identification and monitoring of orthotopic lung tumors.
(A) & (B) Detection of lung tumors by High Resolution Ultrasound Imaging. (A) 2D B-Mode acquisition on a healthy lung in mouse. Vertical white arrows point out the pleural line. Vertical yellow arrows correspond to A lines, representing reverberations of the pleural line. (B) On 2D B-Mode Ultrasound imaging of a lung bearing an orthotopic NCI-H460luc tumor (2.8mmx2.4mm), vertical red arrows point out the margins of the tumor, highlighted by the typical bright shadow artifact. We also remark white and yellow arrows indicating the pleural line and A lines respectively. (C) From 2D to 3D Ultrasound B-Mode imaging of a lung tumor in mouse. The red area corresponds to the lung tumor in the thoracic cavity of the mouse. The red grid corresponds to the tumor volume obtained by tracing margins on each 2D B-mode slices from the 3D acquisition. (D) Assessing tumor burden with BLI (left) and US (right), data are presented as mean ±SEM and statistically analyzed. A two-way repeated-measure analysis of variance followed by Bonferroni post-tests was used for the data of over time course. Differences were considered significant at p< 0.05. Left: Signal intensity from in vivo longitudinal monitoring of tumor proliferation by BLI following the deposition of 1.5x105 or 2.5x105 tumor cells (Photons/sec). Right: In vivo tumor volumes measured by US imaging using a transducer mounted on a 3D motor, comparing the tumor growth between 2 different tumor burdens (mm3). Results represent mean±SEM (n = 5 animals per groups). (***p<0.001; ****p<0.0001).
Fig 3.
Assessment of tumor volumes with micro Computed Tomography.
3D rendering of CT scan anterior and posterior reconstructions, after processing the tumor delineation on 2D slices from coronal, frontal or sagittal plane. Healthy lung parenchyma is blue whereas tumor is highlighted in yellow.
Fig 4.
Correlation analysis between different modalities for tumor volume assessment.
Nonlinear regression of data points collected from orthotopic lung tumors (n = 12 animals). These graphs compare the correlation between 3D US imaging in vivo and ex vivo, in vivo 3D CT scans, ex vivo volumetric measurements and tumor weight.
Fig 5.
Contrast enhanced ultrasound imaging and Photoacoustic imaging of hypoxia on orthotopic lung tumors in mice.
(A) B-mode image of a lung tumor with corresponding contrast image before IV injection of Vevo MicroMarker™. Maximum Intensity Projection after injection of MicroMarker™. (B) B-mode image of a hypoxic lung tumor with corresponding OxyHemo photoacoustic images. With the OxyHemo-Mode, red areas indicate well oxygenated parts of the tumor whereas blue and dark areas indicate the presence of hypoxia. Regarding the 3D volumes, the red grid corresponds to the hypoxic region of tumor and green grid corresponds to the entire tumor. (C) B-mode image of a well oxygenated lung tumor with corresponding OxyHemo photoacoustic images showing absence of any hypoxic core.
Fig 6.
Molecular imaging of VEGFR2 by Targeted Contrast Enhanced Ultrasound Imaging.
(A) & (C) Parametric images of the spatial distribution of contrast agent bubbles. (A) Isotype control conjugated microbubbles. (C) VEGFR2 conjugated microbubbles (Target Ready Vevo MicroMarker™). (B) Corresponding B-Mode image of the tumor. (D) Differential Targeted enhancement of VEGFR2 and Isotype control conjugated microbubbles (dTE corresponds to the difference between the echo power from both targeted and free bubbles, and the echo power from free bubbles only). Statistical analysis was performed with the Student's unpaired t test (n = 4 animals per group). (****p<0.001). (E) Corresponding PA image highlighting hypoxic areas where VEGFR2 is mainly expressed.
Fig 7.
CT scans and bioluminescence signals of mice bearing orthotopic lung tumors.
(A) 2D CT scan of a mouse bearing a lung tumor, after IV injection with 100μL of a mix with PBS and eXIA 160, a iodinated vascular contrast agent. Delineation of the tumor is visible on both planes with a yellow dashed line. (B) CT scan obtained without contrast agent injection. Delineation of the tumor is visible on both planes with a yellow dashed line. (C) Longitudinal BLI study on a mouse bearing a lung tumor between day 7 and day 35 (Photons/sec/cm2/steradian), after implantation of 1.25x105 tumor cells.