Experimental evidence suggests that SSRIs, a popular class of antidepressants, enhance breast cell proliferation during a relatively late phase in breast cancer development, either directly through SSRI tumour-promoting mechanisms [1-3] or indirectly through an SSRI-mediated increase in prolactin, a hormone for which there is increasing evidence to suggest an association with breast cancer [4,5]. This evidence concerns the gene PRL and breast cancer.