As highlighted in this article, recent studies showed that the activation of bitter taste receptors in cancer cells was predominantly associated with anti-cancer effects [17,18,19,20,21] and the downregulation of some TAS2Rs, i.e., TAS2R4, 5, 9, 10 or 14, was associated with poor prognosis [19,20,21], while overexpression counteracted cancer-promoting effects [22]. Here, TAS2R4 is linked to cancer.