MicroRNA control of metastasis

The microRNA, miR-9, controls the spread and development of breast tumours reports a study online in Nature Cell Biology this week. This finding suggests that miR-9 may, in future, be a potential target in development of therapies for breast cancer

Several microRNAs have been found to either activate or repress the spread of tumours. Robert Weinberg and colleagues find that miR-9, directly controlled by the oncogene Myc, allows breast cancer cells to become invasive in mice by regulating levels of the adhesion protein E-cadherin. miR-9 also enhanced blood vessel growth, thereby increasing the tumour's blood supply. As miR-9 levels were elevated in primary tumours from breast cancer patients with malignant tumours, this pathway may be important for human cancer.

An accompanying News and Views article by Greg Goodall discusses the possibility that miR-9 may be important for other tumour types, including neuroblastoma, and what its normal role in development might be.