The Duchenne muscular dystrophy gene and cancer

Background Mutation of the Duchenne muscular dystrophy (DMD) gene causes Duchenne and Becker muscular dystrophy,
degenerative neuromuscular disorders that primarily affect voluntary muscles. However, increasing evidence implicates DMD in
the development of all major cancer types. DMD is a large gene with 79 exons that codes for the essential muscle protein dystrophin.
Alternative promotor usage drives the production of several additional dystrophin protein products with roles that extend beyond
skeletal muscle. The importance and function(s) of these gene products outside of muscle are not well understood.
Conclusions We highlight a clear role for DMD in the pathogenesis of several cancers, including sarcomas, leukaemia’s,
lymphomas, nervous system tumours, melanomas and various carcinomas. We note that the normal balance of DMD gene
products is often disrupted in cancer. The short dystrophin protein Dp71 is, for example, typically maintained in cancer whilst
the full-length Dp427 gene product, a likely tumour suppressor, is frequently inactivated in cancer due to a recurrent loss of 5’
exons. Therefore, the ratio of short and long gene products may be important in tumorigenesis. In this review, we summarise the
tumours in which DMD is implicated and provide a hypothesis for possible mechanisms of tumorigenesis, although the question
of cause or effect may remain. We hope to stimulate further study into the potential role of DMD gene products in cancer and the
development of novel therapeutics that target DMD.