Treatment options for patients with pancreatic cancer are limited and survival prospects have barely changed over the past 4 decades. Chemoradiation treatment (CRT) has been used as neoadjuvant therapy in patients with borderline resectable disease to reduce tumour burden and increase the proportion of patients eligible for surgery. Antimetabolite drugs such as gemcitabine and 5-fluorouracil are known to sensitise pancreatic tumours to radiation treatment. Likewise, photodynamic therapy (PDT) has also been shown to enhance the effect of radiation therapy. However, PDT is limited to treating superficial lesions due to the attenuation of light by tissue. The ability of the related technique, sonodynamic therapy (SDT), to enhance CRT was investigated in two murine models of pancreatic cancer (PSN-1 and BxPC-3) in this study. SDT uses low intensity ultrasound to activate an otherwise non-toxic sensitiser, generating toxic levels of reactive oxygen species (ROS) locally. It is applicable to greater target depths than PDT due to the ability of ultrasound to propagate further than light in tissue. Both CRT and the combination of CRT plus SDT delayed tumour growth in the two tumour models. In the PSN-1 model, but not the BxPC-3 model, the combination treatment caused an increase in survival relative to CRT alone (p = 0.038). The improvement in survival conferred by the addition of SDT in this model may be related to differences in tumour architecture between the two models. MRI and US images showed that PSN-1 tumours were less well perfused and vascularised than BxPC-3 tumours. This poor vascularisation may explain why PSN-1 tumours were more susceptible to the effects of vascular damage exerted by SDT treatment.
|Number of pages||7|
|Journal||Journal of Controlled Release|
|Early online date||16 Jul 2021|
|Publication status||Published (in print/issue) - 10 Sept 2021|
Bibliographical noteFunding Information:
RJB was supported through a Pancreatic Cancer Research Fund grant. KAV and SA acknowledge support from Cancer Research-UK ( C5255/A15935 ). KAV, PDA, VK, SW, PK, and SS received funding through the CRUK/EPSRC Cancer Imaging Centre Oxford ( C5255/A16466 ). KAV and ES acknowledge support from the EPSRC Oxford Centre for Drug Delivery Devices ( EP/L024012/1 ).
- sonodynamic Therapy
- pancreatic cancer
- oxygen microbubbles