Faithful companions: a proposal for neurooncology trials in pet dogs

Area of Science:

• Neuro-oncology
• Comparative oncology
• Preclinical cancer research

Background:

• Malignant glioma (MG) is a rare but aggressive brain cancer often used to test new cancer therapies.
• Current preclinical models, such as murine orthotopic xenografts, have significant limitations and do not accurately represent human MG.
• These limitations create discontinuities between preclinical findings and human clinical outcomes.

Purpose of the Study:

• To critically evaluate the limitations of current preclinical models for malignant glioma research.
• To explore alternative preclinical models, including transgenic mouse models and canine xenografts.
• To advocate for the use of companion animals with spontaneous brain cancers as a more suitable model system for testing novel MG interventions.

Main Methods:

• Review and analysis of existing literature on preclinical models for malignant glioma.
• Discussion of the scientific and ethical considerations of various model systems.
• Comparative assessment of murine orthotopic xenografts, transgenic mouse models, and canine xenografts.

Main Results:

• Murine orthotopic xenografts exhibit numerous discontinuities with human malignant glioma, limiting their predictive value.
• Alternative models like transgenic mice and canine xenografts show potential but also have drawbacks.
• Companion animals with naturally occurring brain cancers present a scientifically valid and ethically sound alternative.

Conclusions:

• Companion animals with spontaneous brain tumors offer a highly attractive model for preclinical testing of novel malignant glioma therapies.
• This approach provides a more translatable and ethically advantageous system compared to traditional xenograft models.
• Further exploration of companion animal models is warranted to advance malignant glioma research and treatment.