Stress hormones induce breast intra-tumor heterogeneity

Diversity within or between a tumour and metastases, known as intra-patient tumour heterogeneity develops during disease progression, and is a serious hurdle for therapy1,2,3. Metastasis is the fatal hallmark of cancer and mechanisms of colonization, the most complex step of the metastatic cascade4,5, remain ill-defined. Better understanding of cellular and molecular processes underlying intra-patient tumour heterogeneity and metastasis are pivotal for the success of personalized cancer treatment. Here, transcriptional profiling of tumours and matched metastases showed cancer site-specific phenotypes, and identified increased glucocorticoid receptor (GR) activity in the distant metastases. GR has been shown to mediate the effects of stress hormones and of their synthetic derivatives, widely used in the clinic as anti-inflammatory and immunosuppressive.