Considering the well-established role of PrP in signalling (Chiarini et al. 2002; Mattei et al. 2020; Mouillet-Richard et al. 2000) and the growing evidence for sPrP acting as a ligand or trophic factor in intercellular communication (discussed herein), further studies are warranted to check for a mechanistic relevance in cancer biology. This evidence concerns the gene PRNP and cancer.