Disclosures Dr. Pollak has consulted for Sanofi-Aventis, Novo Nordisk, Merck-Serono and Pfizer.
Insulin analogues and cancer risk: cause for concern or cause célèbre?
Version of Record online: 26 FEB 2010
© 2010 Blackwell Publishing Ltd
International Journal of Clinical Practice
Volume 64, Issue 5, pages 628–636, April 2010
How to Cite
Pollak, M. and Russell-Jones, D. (2010), Insulin analogues and cancer risk: cause for concern or cause célèbre?. International Journal of Clinical Practice, 64: 628–636. doi: 10.1111/j.1742-1241.2010.02354.x
- Issue online: 10 MAR 2010
- Version of Record online: 26 FEB 2010
- Paper received December 2009, accepted January 2010
People with diabetes, particularly those with type 2 diabetes, may be at an increased risk of cancer. Furthermore, their cancer risk may be modified by treatment choices. In this respect, metformin may be protective, whereas insulin and insulin analogues can function as growth factors and therefore have theoretical potential to promote tumour proliferation. Analogues causing inappropriate prolonged stimulation of the insulin receptor, or excess stimulation of the IGF-1 receptor, are the most likely to show mitogenic properties in laboratory studies. Some recent epidemiological studies appear to be consistent with these experimental findings, suggesting that there could be different relative risks for cancer associated with different insulins, although these studies have attracted some methodological criticism. However, it is biologically plausible that hormonal factors that influence neoplasia could begin to manifest their effects in surprisingly short timescales (within 2 years) and hence these epidemiological studies justify further research. Even if future research were to document an increase in cancer risk among insulin users, this would be unlikely to significantly diminish the favourable benefit-risk ratio for patients requiring insulin therapy. There is a need for further population studies and for the development of new laboratory models that are more sophisticated than previous experimental methods employed to assess potential tumour growth-promoting properties of insulins.