Dissolving the boundaries – physics and biology come together for cancer

First of all, tell us about the Physics of Life

For many, the overlap of the discipline of physics and the life sciences will be most closely associated with the various technologies originating in the physics laboratory – the various forms of microscopy that have revolutionised biological imaging being a prime example.

However, the Physics of Life programme covers a much broader canvas. It is concerned with the science that emerges at the interface between the physical and biological sciences, including the application of theoretical techniques – which have their origins in areas such as condensed matter and statistical physics – to biological systems.

The field’s ‘grand challenge’ is undoubtedly ambitious; to develop a unified framework for understanding the biology that integrates the molecular and the system levels of description into a coherent, unified whole.

In a sense, this is simply a re-statement of a long-standing goal for biologists. It’s tempting to suggest that the traffic is all one way – that physics is just applied to the development of a theory of biology by using mathematics in much the same way that mathematics is the powerful explanatory framework for the quantum world or cosmology. But this is not true – the deeply complex world of biology is yielding new physics and intellectual hurdles that are at least as challenging as string theory.

None of this is news to biologists, of course, but it does underscore the fact that, any productive conversation between physicists and biologists will be continuous and two-way.

One recent development is the increasing prominence of the biomedical domain – the physics of medicine. Of course, physics has a long tradition of making significant contributions to medicine, not least in areas such as radiology where almost all the current imaging techniques have their origins in the applied physics laboratory. Funded by the Rosetrees Trust, a Physics of Medicine programme has featured prominently as part of the wider UKRI-funded Physics of Life network.

Cancer Research UK have also long-recognised the value of engaging physical scientists and mathematicians in cancer research and co-funded two of the workshops in the Rosetrees programme, including one on metastasis, and one on drug resistance.

This workshop provided several outstanding illustrations of how physical and medical sciences can interact productively. Great examples, I think, were the work of Julia Yeomans’ group in the Physics Department at Oxford which demonstrated the role that the theory of active matter plays in understanding the budding processes characteristic of metastasis. Also Victor Perez-Garcia’s group, who used tumour imaging and metabolic data from different cancers to show that tumours obey a so-called super-linear scaling law. This work suggests the volume of growth of a tumour could become a useful measure of potential lethality.

Science is often criticised as being too ‘siloed’ – researchers can become entrenched in their own field and don’t look to other disciplines for either inspiration or practical solutions to their own challenges. So, how can we get the balance between deep disciplinary knowledge and interdisciplinary approaches right?

Given the many examples of how the physical and biological sciences are increasingly interacting productively, it might be tempting to assume that in practice there are no barriers to the deep interdisciplinary research (IDR) collaborations so vital to the success of the field.

However, the tendency to silo different areas of science is the bane of Physics of Life. So, in common with the broader challenges of interdisciplinary research, a sustained programme of initiatives is required to strengthen the Physics of Life community.

To raise awareness and ensure interdisciplinary research is effective, advanced training is needed to enable upcoming generations of researchers to identify a substantial area of interdisciplinary research and follow it through to impact. Many joint honors degrees do exist but, despite this landscape, the research itself still seems to silo.

UKRI’s funding of three successive Physics of Life networks has proved pivotal in growing and sustaining the community, particularly for early career researchers. A recent UKRI-funded post-doctoral career fellowship award scheme provided ample evidence for the enthusiasm and engagement of ECRs. The scheme also highlighted the continuing need for mentorship to support researchers moving into interdisciplinary research, a move which can be quite daunting, particularly for those unsure of the impact on their future career.

The number and quality of the applications to the recent £33m Physics of Life Strategic Priority Fund: ​Building Collaboration at the Physics of Life Interface, jointly funded by UKRI and Wellcome, was testament to the vigour of the field.

The ultimate goal is that such applications are not put at risk by the challenges to interdisciplinary research and instead become “business as usual”.

Tell us a bit about your academic background, and why you feel so passionately about bringing disciplines together?

My own route into this fascinating and challenging field is non-standard I’d say. I studied Physics with Theoretical Physics at Cambridge, having given up biology in the sixth form.

The reason for my unwise and premature decision to ditch biology was that it seemed to be principally about a “list of parts” rather than underlying principles. Frankly, it struggled to compete with the beauty and parsimony of mathematical physics, which seemed both comprehensive and fundamental.

I subsequently worked as a medical physicist in the NHS, being fortunate enough to have the opportunity of completing a part-time PhD (on the mathematics of hyperaemia) in the maths department at Leeds. This, and my subsequent work in applying mathematics to various problems in medicine, confirmed the power of a mathematical approach to at least some of medicine’s grand challenges.

Perhaps amusingly, during the 90s’, I led some work applying neural networks to two clinical data sets in an attempt to see if they offered some useful insights and predictions. The answer was “no”, although it is now clear that it should have been “not yet – first collect accurate data”.

Becoming R&D Director at Leeds and a memorable time helping establish the National Institute for Health and Care Research provided me with a privileged view of the many research challenges across a wide range of specialties in medicine, all of which underlined the need to look for solutions from disciplines outside medicine.

Having been involved with the Physics of Life network since 2018 and the Rosetrees programme since 2020, I am deeply encouraged by the openness of many disciplines, including clinicians, to engage with scientists from outside their area to see if, and how, they may be able to provide insights into the many and rich questions in biology and medicine.

I am convinced that deep inter-disciplinarity is not a passing fad but a necessary response to the many exciting challenges in cancer research and science more generally and I am very optimistic that the lessons we have learnt in the Physics of Life will stand the test of time.