Of Mice and Medicine: Conducting Cancer Research in Mouse Models

By: Dr Nadiah Abu (nadiah.abu@ppukm.ukm.edu.my)

There are several reasons why medical researchers use mice as cancer models:

1. Convenience: Mice are relatively small, easily housed and maintained, adaptable, have a short life span and reproduces quickly.
2. Relatively inexpensive: Can be bought in large amount without requiring a lot of space.
3. Biologically relevant to humans. Can be used to study a wide range of diseases. Easier to mimic human conditions in rodents.
4. Well-understood by researchers. Easier to manipulate with expected outcomes.

Experimental Design and Considerations:
Depends on experimental objectives, costs, facilities and expertise.

1. Animal selection: Does the animal require a competent immune system? Eg: is tumor microenvironment relevant in your research?
2. Animal welfare: There is a need to acclimatize mice to new environment. Does it require special diet?
3. Tumor induction: Subcutaneously or surgically? Ectopic or orthotopic?
4. Tumor evaluation: For external tumors, Vernier calipers can be used. For internal tumors, do they require a specific imager?
5. Drug/Treatment administration: Route of administration? Volume? Dosage required per weight of mice?
6. What to monitor: Body weight, behaviour, food intake, locomotion.

Euthanasia: Should result in rapid loss of consciousness, without other animals watching, pain/stress free environment.

Notes:

1. Doing animal study is about teamwork.
2. Always plan ahead and anticipate the worst possible outcome.
3. Define your objectives properly before using experimental animals.
4. Do extensive literature review search.
5. Treat animals with respect.