Aberrant expression of pyloric gland-type mucin in mucin-producing bile duct carcinomas: a clear difference between the core peptide and the carbohydrate moiety.
The authors have recently defined the clinopathological entity of a mucin-producing bile duct tumor (MPBT), and divided MPBT into two distinct subtypes: 'columnar-type' and 'cuboidal-type' MPBT. Mucin core protein 6 (MUC6), which is present in normal pyloric glands, had higher expression levels in cuboidal-type tumors than in columnar-type tumors. In the pyloric glands, a carbohydrate antigen detected by monoclonal antibody HIK1083 (CA/HIK1083) is also expressed. In order to evaluate the coexpression pattern of MUC6 and CA/HIK1083 in MPBT, expression profiles were evaluated in 38 surgically excised mucin-producing bile duct carcinomas (MPBC; cuboidal-type, n = 15; columnar-type, n = 23), using immunohistochemistry. The staining rate was graded as follows: -, <5% of neoplastic cells stained; +, 5% to <20%; + +, 20% to <50%; + + +, > or =50%. In cuboidal-type MPBC, MUC6 was positive in all cases (+ + +, 13/15; + +, 1/15; +, 1/15), whereas CA/HIK1083 was negative in all cases (-, 15/15; P < 0.0001). In columnar-type MPBC, MUC6 was positive in 65% of cases (+ + +, 6/23; + +, 8/23; +, 1/23; -, 8/23), and CA/HIK1083 was positive in 52% (+ +, 3/23; +, 9/23; -, 11/23; not significant). Our results clearly demonstrate that cuboidal-type MPBC have an aberrant pyloric glandular phenotype, that is, MUC6+/CA/HIK1083-. This unique profile may be related to different outcomes of patients with MPBC.
Goto
Masamichi
M
Department of Human Pathology, Field of Oncology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Shibahara
Hiroaki
H
Tamada
Shugo
S
Hamada
Tomofumi
T
Oda
Koji
K
Nagino
Masato
M
Nagasaka
Tetsuro
T
Imai
Kohzoh
K
Nimura
Yuji
Y
Yonezawa
Suguru
S
D002288:Adenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000032:analysis; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000096:biosynthesis / Q000276:immunology; D001650:Bile Duct Neoplasms / Q000378:metabolism / Q000473:pathology*; D017734:Bile Ducts, Extrahepatic / Q000737:chemistry / Q000473:pathology; D002241:Carbohydrates / Q000032:analysis; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D055272:Mucin-6; D009077:Mucins / Q000096:biosynthesis* / Q000737:chemistry; D010455:Peptides / Q000032:analysis
D000911:Antibodies, Monoclonal; D015295:Antigens, Tumor-Associated, Carbohydrate; D002241:Carbohydrates; C524734:MUC6 protein, human; D055272:Mucin-6; D009077:Mucins; D010455:Peptides