1. Microbubble-Ultrasound Radioenhancement of Bladder Cancer William Tyler Tran Radiation Therapist & Clinical Research Associate Department of Radiation Oncology and Medical Imaging Research Sunnybrook Health Sciences Centre, Toronto, Ontario Canada Principle Investigator: Dr. Gregory Czarnota Assistant Professor & Clinician Scientist Department of Radiation Oncology and Medical Imaging Research Project Research Associates: Sara Iradji, Anoja Giles, Ervis Sofroni

3. Synopsis -Microbubbles -Tumourigenesis and Vascularity -Purpose of Study -Materials and Methods -Results of Study -Discussion and Implications -Questions

4. Microbubbles -Contrast Agents in Ultrasound -Microspheres measuring 1.2- 3.1µm average diameter -Lipid/Protein/Biopolymer shell -Gas filled inner core (Perflutren) RBC MB Quaia (2007)

5. Cavitation Inertial Non Inertial Microbubbles Ultrasound Thermal Effects Characteristic EchogenicityEnergy Deposition

6. Microbubble Applications Albrecht et al. (2000 ) Meair, Culps (2009)

7. KOBAYASHI et al. (2002) -Contrast agents were sequestered into the vascular lumen -Contrast agents targeted endothelial cells. -Endothelial cells were abrogated

8. Tumorigenesis and Vascularity: Endothelial cells are recruited during tumourigenesis and neovascularization

10. The Study Tumors are very dependent on vascularture + Vasculature feeds the tumor with oxygen, nutrients and circulates cell signals for growth + Radiation also disrupts Endothelial Cells

11. Ultrasound mediated microbubbles can be used as a Vascular Targeting Agent (VTA) in combination with Radiation to abrogate tumor blood vessels and enhance radiotherapy response in Bladder Cancer Xenografts

12. Methods and Materials

15. Results

16. Microbubbles effectively target vasculature in HT-1376 Bladder Cancer Xenografts in vivo.

18. The combination of ultrasound-activated microbubbles and radiation synergistically decreases vasculature in HT-1376 Bladder Cancer tumors in vivo.

20. The combination of ultrasound activated microbubbles and radiation significantly collapses the tumour compartment.

23. Discussion

24. Hypoxia How does decreasing the vascular density increase oxygenation? Aren’t vessels needed to deliver oxygen and nutrients?

25. Vascular Denormalization Teicher et al. (1995) Lung carcinoma growing subcutaneously in hind leg of male C57BL mice. Treatment given to these mice TNP-470 and minocycline (antioangiogenic agent) Measured oxygen levels using polarographic oxygen electrode. Results of the studies indicated that there were decreased hypoxia (i.e. Increased oxygen) in these tumour microenvironments Jain et al.

26. Conclusions

27. Acknowledgements AACR Michelle Martin (Veterinary Technician) Czarnota Laboratory Sheila Robson & Lisa DiProspero, Dept. of Radiation Therapy, SHSC

28. Addendum I: Combining agents that disrupt the vasculature and radiation Study by Raben et al. used ZD126 in combination with radiation therapy and found improved treatment outcome. Kozin et al. used VEGFR2 antibody treatment, an antioangiogenic agent that disrupts VEGF pathways in combination with radiation therapy.

29. Addendum I: Combining agents that disrupt the vasculature and radiation