OR51E2 and Familial prostate cancer: The functional role of the β-ionone-activated OR51E2 was previously described for prostate cancer cells, epidermal melanocytes and melanoma cells, whereby OR51E2 regulates the proliferation, migration, invasiveness and pigmentation (Neuhaus et al., 2009; Rodriguez et al., 2014; Sanz et al., 2014, 2017; Gelis et al., 2016, 2017).