The animals we use

Animals are used in our research to help us understand the mechanisms that underpin cancer, such as the growth and spread of tumours, and to develop new ways of diagnosing, treating and preventing the disease. 

Our work at the ICR mainly uses mice, which can grow tumours which mimic those of human cancer patients. Studies of cancer in mice mimic the complex way tumours grow and spread in people with cancer.

Mice can be easily genetically altered to allow us to study the genetic causes of cancer and reproduce tumour types which naturally occur in humans in the correct tissues and body systems, for example we use mice which have been genetically engineered so they develop the equivalent of children’s cancers affecting the brain and nervous system. We have had great success in developing treatments for these cancer types which have helped many children.

In other studies we implant cancer cells from a patient’s tumour into a mouse organ. This has the advantage that we can study a human cancer with a whole organism.

We also conduct some studies in rats. We use rats when we need to work on a slightly larger animal, if for example the research involves studying blood vessels, involves surgery or some types of imaging.

Each year we record the number of animals that we have used at the ICR, to report back to the Home Office. Information from the last 14 years is shown in the table below.

Procedures we do

Common procedures include giving drugs through injections or through a tube into their stomach. We also do surgical procedures on some mice and rats under anaesthetic – for example to implant tumour cells under the skin.

We will try new treatments in mice before selecting the most promising to take forward into clinical trials in patients. You can read more about this work in a case study on using mice to help discover new treatments for childhood cancers.

In studies of new cancer treatments, researchers test whether a potential drug can shrink a tumour or slow its growth. To obtain robust and meaningful data, it is important that scientists can accurately measure the size of tumours in mice to see whether the treatment being tested is having any effect. 

We often use imaging techniques like MRI, commonly also used for human patients, to measure the size of tumours in mice. The mice will be scanned in small versions of the same machines used for patients in the hospital.

Our facilities

Animal welfare is very important to us at the ICR and we ensure that our animals are well cared for. We have led the development of best practice in animal welfare in cancer research, helping develop the Guidelines for the welfare and use of animals in cancer research which are used by cancer researchers in the UK and worldwide. You can read more about the legislative landscape, ethics and welfare. 

We have state-of-the-art facilities which ensure we carry out good-quality research in controlled conditions. Our animals live in an ultra-clean environment in cages that protect them from pathogens. Our facilities provide filtered air, ultraclean water, and sterile bedding and nesting, carefully monitored to maintain a high-quality environment. We enrich cages with items that our animals can interact and play with, as an important part of looking after their welfare.

You can find out more about animal research at the ICR by reading our case study on using mice to mimic childhood cancers.