PCNX2 and neoplasm: The other 3 new genes are FHIT (Fragile Histidine Triad), PCNXL2 and SEPT11. FHIT encodes a diadenosine 5′,5′′′-P1,P3-triphosphate hydrolase and is known as a tumour suppressor gene in a variety of common human cancers47, 48.