Pancreatic tumours: molecular pathways implicated in ductal cancer are involved in ampullary but not in exocrine nonductal or endocrine tumorigenesis.
Alterations of K- ras, p53, p16 and DPC4/Smad4 characterize pancreatic ductal cancer (PDC). Reports of inactivation of these latter two genes in pancreatic endocrine tumours (PET) suggest that common molecular pathways are involved in the tumorigenesis of pancreatic exocrine and endocrine epithelia. We characterized 112 primary pancreatic tumours for alterations in p16 and DPC4 and immunohistochemical expression of DPC4. The cases included 34 PDC, 10 intraductal papillary-mucinous tumours (IPMT), 6 acinar carcinomas (PAC), 5 solid-pseudopapillary tumours (SPT), 16 ampulla of Vater cancers (AVC) and 41 PET. All tumours were also presently or previously analysed for K- ras and p53 mutations and allelic loss at 9p, 17p and 18q. Alterations in K- ras, p53, p16 and DPC4 were found in 82%, 53%, 38% and 9% of PDC, respectively and in 47%, 60%, 25% and 6% of AVC. Alterations in these genes were virtually absent in PET, PAC or SPT, while in IPMT only K- ras mutations were present (30%). Positive immunostaining confirmed the absence of DPC4 alterations in all IPMT, SPT, PAC and PET, while 47% of PDC and 38% of AVC were immunonegative. These data suggest that pancreatic exocrine and endocrine tumourigenesis involves different genetic targets and that among exocrine pancreatic neoplasms, only ductal and ampullary cancers share common molecular events.
Moore
P S
PS
Department of Pathology, Università di Verona, Italy.
Orlandini
S
S
Zamboni
G
G
Capelli
P
P
Rigaud
G
G
Falconi
M
M
Bassi
C
C
Lemoine
N R
NR
Scarpa
A
A
D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014670:Ampulla of Vater / Q000378:metabolism / Q000473:pathology; D001483:Base Sequence; D018267:Carcinoma, Acinar Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002291:Carcinoma, Papillary / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D003138:Common Bile Duct Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis / Q000235:genetics; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000032:analysis / Q000235:genetics; D004701:Endocrine Gland Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D004702:Endocrine Glands / Q000378:metabolism / Q000473:pathology; D005088:Exocrine Glands / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D019656:Loss of Heterozygosity; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018807:Polymorphism, Single-Stranded Conformational; D051901:Smad4 Protein; D015534:Trans-Activators / Q000032:analysis / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000032:analysis / Q000235:genetics; D018631:ras Proteins / Q000032:analysis / Q000235:genetics
D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins; C497796:SMAD4 protein, human; D051901:Smad4 Protein; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; D004247:DNA; D018631:ras Proteins