Photo of supporters at a Race for Life event.

Supporters at a Race for Life event. Supporters at a Race for Life event.

This blog post was updated in June 2018.

More people are surviving cancer than ever before.

Thanks to decades of research, survival from cancer has doubled in the last 40 years, giving thousands of people more time with their loved ones. In fact, more than half of all patients will now survive for at least ten years.

But this progress simply wouldn’t have been possible without animal research.

At Cancer Research UK, research involving animals is part of our efforts to beat cancer. This includes discovering the faulty genes and molecules that cause cancer, investigating how the disease grows and spreads, developing and testing new treatment and tests, and exploring how our immune system can help fight tumours.

And it’s a legal requirement in this country that all new drugs (not just cancer drugs) must be tested in animals before they’re given to people, to make sure that they’re safe to use.

Some animal rights organisations have called for Cancer Research UK and other medical research charities to stop funding animal research. While animals continue to play a vital role in making progress against cancer, we fund and support research into ways to reduce and even replace animals in research where possible. But at the moment it’s not feasible to replace animals in medical research altogether.

Our research is entirely supported by public donations, and cancer patients are at the heart of everything we do. We understand not everyone agrees with animal research, but currently it’s crucial to make sure more people survive this terrible disease.

What animal research does Cancer Research UK do?

Much of our work doesn’t involve animals, and wherever it’s possible our researchers rely on other methods. Some use cells taken from human tumours, others study cell processes in yeast or bacteria, and some use computer models to study cancer.

They’re also looking at entirely new approaches, such as ‘artificial tumours’ and tissue grown from stem cells in the lab.

But for many of our scientists working to beat cancer, animal research is an essential part of their jobs. In some areas there’s simply no other way to get the information needed to make progress against the disease.

All our researchers follow strict laws – some of the most stringent in the world – that ensure that animals are treated humanely and only used when there’s no alternative. Sometimes, we fund animal research outside of the UK and, in these cases, we require overseas researchers to follow UK standards, even if they are stricter than the researchers’ national laws.

All animal research funded by Cancer Research UK goes through a strict ethical review process to ensure the highest standards of care and welfare for all animals involved in our research. Our scientists make every effort to reduce the number of animals used in research, to refine the research so that animal welfare is improved, and to replace the use of animals wherever an alternative is available (the so-called ‘3Rs‘).

Many of our scientists need to study cells and processes in living organisms. Some of them use flies, fish, worms and yeast because these can give scientists a good idea of how human cells behave.

But for other research it’s essential to use mammals – most commonly mice or rats – because the complex interactions between cells and tissues in the human body can’t be mimicked with simpler, non-mammalian animals. Mice are remarkably similar to humans in terms of their genetic make-up, so studying them helps us understand cancer in humans.

How does Cancer Research UK ensure we only involve animals when it is absolutely necessary?

Our researchers are committed to improving animal research by following the 3Rs outlined above. Scientists who apply to Cancer Research UK for funding submit applications that describe the research that they plan to carry out, and the potential benefit this will have for cancer patients. Independent experts then review these applications before Cancer Research UK decides whether to fund the research.

When animal research is proposed, the scientists must show that there are no feasible alternatives to using animals, that the experiments are properly designed and that all measures have been taken to address the 3Rs. They also have to ensure that animals will be cared for to minimise harm or distress, and that there are appropriate facilities to ensure the highest standards of animal welfare.

How does Cancer Research UK support the development of alternatives to animal research?

To make sure that the fewest number of animals are used in research, and that the maximum benefit comes from these experiments, we also fund scientists to develop ways of researching cancer that do not involve animals, or that use fewer animals than current methods. This includes experiments on cells grown in the lab, examining samples of human tumours and using sophisticated computer programmes to understand how cancer behaves.

For example, our PEACE study is shedding light on what happens during the final stages of cancer. Traditionally this type of research would have been carried out in animals, but this nationwide project is collecting samples from people who have died from cancer in a bid to understand how tumours spread and stop responding to treatments. In turn, this innovative approach could reveal new ways to tackle the disease.

You can read more about how we are replacing, reducing and refining the use of animals in cancer research here.

How has animal research helped to save lives?

Studies using animals have underpinned virtually all the progress that has been made in understanding and treating cancer over the past century, from giving clues to causes of the disease to showing us the best ways to treat it.

For example, the breast cancer drug tamoxifen – arguably one of the most important cancer drugs of all time – was developed with the aid of animal research. Over the years, it has saved hundreds of thousands of women’s lives.

The targeted drug imatinib (Glivec) can now cure people with chronic myeloid leukaemia. The original studies that identified imatinib’s potential were carried out in mice.

The development of antibody treatments for cancer has also relied on animal research. Antibodies are molecules designed to recognise and target cancer cells, and early research in mice helped to find a way to produce large enough quantities of these molecules to be used to treat patients.

Antibodies can now be made in industrial quantities without using animals, and these treatments are used for several types of cancer. New immunotherapy drugs called ‘checkpoint inhibitors’ which help the immune system recognise and attack cancer are just one example. These drugs have transformed the outlook for some people with advanced disease, such as melanoma, and wouldn’t have been possible without animal research.

This story is repeated time and time again with other advances in cancer research, and studies in animals continue to be vital in bringing benefits to cancer patients and saving lives around the world.

Right now, animal research is helping scientists study how tumours develop and change over time. And it’s this information that’s helping researchers identify new ways to tackle the disease, making treatments more precise. For example scientists can grow ‘avatars’ of people’s tumours in mice as a way to test out which drugs might be best for individual patients. Studies of dogs that naturally develop brain tumours could also guide researchers towards better treatments for these hard to treat cancers, benefitting not only people but canines, too.

A better future thanks to animal research

These are only a few examples of the countless benefits animal research has brought to people with cancer, but there are thousands of other drugs and treatment techniques that are built on knowledge from tests in animals.

And it’s not just cancer patients that benefit from animal research. As the Royal Society’s position statement on the use of animals in research points out, ‘virtually every medical achievement in the past century has depended directly or indirectly on research on animals.’

At Cancer Research UK, animal research is never undertaken lightly – we seek to use alternatives wherever it’s possible, and fund research into alternative methods as well. But this fact remains – millions of people all over the world are alive today thanks to animal research. Much of this knowledge has also been used to tackle diseases that affect animals themselves, including cancer.

Many people working for and supporting us know first-hand how devastating cancer can be, and all of us are deeply committed to beating the disease. Animal research is, at present, a necessary means to an end: helping people with cancer to survive.

Dr David Scott, Director of Discovery Research and Research Funding