The presence of PaCSs in gastric preneoplastic lesions, and their selective colocalization with putative oncogenic factors like CagA, SHP2 and members of the MAPK/ERK signaling system, may suggest this structure has a role in the regulation of cell growth and neoplastic transformation, also in view of its highly enriched UPS content and the mounting evidence for a role of UPS in cancer origin or progression. This evidence concerns the gene HMBS and cancer.