• Higher activation of MYC and E2F3 pathways in luminal-B tumours compared with luminal-A, an observation consistent with many previous results associating amplification of the 8q24 locus and overexpression of cell-cycle and proliferation genes with the more aggresive luminal-B phenotype [43,53-55] (P < 10-10). The gene discussed is MYC; the disease is neoplasm.