Despite the early and frequent silencing of HES5 in prostate cancer, we observed variable expression of the HES5 transcriptional target HES6 in prostate tumour samples (Fior & Henrique 2005) (Fig. 3f and Supplementary Figure 5f), prompting us to investigate other factors that may regulate HES6 expression in prostate tumour cells. This evidence concerns the gene HES5 and Familial prostate cancer.