A MATHEMATICAL model has been used in a new study that has investigated the impact of an ageing immune system on the risk of developing cancer according to results of research conducted at the University of Dundee, Dundee, UK. Although cancer is widely accepted to be caused by an accumulation of genetic mutations over time, which can be accelerated by controllable risk factors, including tobacco smoking, obesity, and alcohol consumption, it is also clear that as humans age, the effectiveness of the immune system decreases, making us more susceptible to this disease.
Natural decline in thymus size occurs in all humans, and the gradual decrease in organ volume over time is one of the main drivers behind the deterioration in immune system functionality. The researchers therefore produced a mathematical model that estimated how the number of cancer cases would increase as a result of immune system deterioration. The findings were compared with 2 million real-life cancer patients ranging from 18–70 years old.
The research team found that their model of immune system deterioration in cancer cases fit the pattern observed in the real-world cases more closely than the standard multiple-mutation hypothesis. There was also a greater number of males affected by immune system deterioration-related cancers, which was thought to be triggered by a more rapid decrease in the size of the male thymus compared to the reduction seen in female patients.
The study authors acknowledged that these conclusions are drawn from the result of a single mathematical study, and therefore need to be scrutinised and replicated in the real world to confirm the findings. However, the study marks a paradigm shift in the understanding of how and why cancers develop, and the model could lead to a revolution in how cancers are proactively prevented, rather than the reactive treatment currently used. Dr Thea Newman, senior study author and formerly Vice Principal of Research and Professor of Biophysics and Systems Biology at The University of Dundee, commented: “This is still very early days, but if we are proven right, then you could be talking about a whole new way to treat and prevent cancer.”