Fig 1.
Surgical implantation of an LS174T tumor fragment (1 mm3) onto the cecum was initially performed. Tumors grew 3 weeks and then were imaged with the Pearl Trilogy Small Animal Imaging System. At week 0, initial PIT treatment was performed. At week 1, group 3 received repeat PIT and tumors were measured with calipers. At week 2, mice were sacrificed and tumor size measured.
Fig 2.
In vitro PIT cell viability with increasing exposure to laser intensities.
LS174T cells (2,000) were seeded into each well. Treatment groups were incubated with media containing m5A-700. Lower levels of cell viability were demonstrated in a dose-dependent fashion, with the lowest percentage of cell viability in wells that received 16 J/cm2 of laser exposure (p < 0.001).
Fig 3.
Comparison of pre-treatment and post-treatment fluorescence imaging in orthotopic LS174T mouse models.
The mouse received 25 μg m5A-700 24 hours before treatment. Prior to PIT treatment (a), tumor margins had a distinct NIR fluorescence signal (maximum tumor fluorescence 4.54). After PIT treatment (b), maximum fluorescence signal decreased to 2.82. (c) Mean maximum fluorescence tumor signal before and after PIT (n = 12). There is a significant difference between mean tumor fluorescence signal before and after treatment with PIT (p < 0.001). Error bars represent standard error of the mean.
Fig 4.
PIT was delivered to both treatment groups at week 0. PITx2 group received repeated PIT at week 1. There was a significant difference between PITx2 tumor volume and control tumor volume at week 2 (p < 0.05).