Distinct expression pattern of claudin-6, a primitive phenotypic tight junction molecule, in germ cell tumours and visceral carcinomas.

Abstract

AIMS:

This study aimed to clarify claudin-6 expression patterns in cancers.

METHODS AND RESULTS:

We surveyed claudin-6 expression by immunohistochemistry using tissue microarray in 860 tumours, including germ cell tumours and major carcinomas. Claudin-6 was expressed consistently in germ cell tumours (28 of 28, 100%), whereas only 64 (8%) of 832 non-germ cell tumours demonstrated claudin-6 expression. Further immunohistochemical study in full tissue sections demonstrated diffuse claudin-6 staining in all seminomas (n=14), embryonal carcinomas (n=10), yolk sac tumours (n=12) and mononuclear trophoblastic cells of choriocarcinomas (n=3), and focal staining in immature epithelial components of immature teratomas (n=6). Additionally, because alpha-fetoprotein (AFP)-producing gastric adenocarcinomas and pulmonary high-grade fetal adenocarcinomas were among the claudin-6 expressing non-germ cell tumours in the microarray studies, we predicted that claudin-6 may be a biomarker for them and studied additional tumours in full sections, which showed claudin-6 expression in AFP-producing gastric adenocarcinomas (18 of 20, 90%) and pulmonary high-grade fetal adenocarcinomas (four of five, 80%). Only one of 11 hepatoblastomas demonstrated focal claudin-6 staining.

CONCLUSIONS:

This study demonstrated that claudin-6 is a novel diagnostic marker for primitive germ cell tumours and is also expressed frequently in some cancers with a primitive phenotype.

• Authors: Tetsuo Ushiku, Aya Shinozaki-Ushiku, Daichi Maeda, Shigeki Morita, Masashi Fukayama
• Journal: Histopathology (Histopathology) Vol. 61 Issue 6 Pg. 1043-56 (Dec 2012) ISSN: 1365-2559 [Electronic] England
• PMID: 22803571 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2012 Blackwell Publishing Limited.

Chemical References

• Biomarkers, Tumor
• Claudins
• alpha-Fetoproteins
• claudin 6

Topics

• Adenocarcinoma (metabolism, pathology)
• Biomarkers, Tumor (metabolism)
• Carcinoma, Embryonal (metabolism, pathology)
• Claudins (metabolism)
• Endodermal Sinus Tumor (metabolism, pathology)
• Female
• Fetus (metabolism, pathology)
• Humans
• Lung Neoplasms (metabolism, pathology)
• Male
• Neoplasms, Germ Cell and Embryonal (metabolism, pathology)
• Phenotype
• Seminoma (metabolism, pathology)
• Stomach Neoplasms (metabolism, pathology)
• Testicular Neoplasms (metabolism, pathology)
• Tight Junctions (pathology)
• alpha-Fetoproteins (metabolism)