A potential role for 6-sulfo sialyl Lewis X in metastasis of bladder urothelial carcinoma.

Abstract

OBJECTIVES:

It is widely accepted that sialyl Lewis X (sLeX) and sialyl Lewis A (sLeA, also known as CA 19-9) glycans expressed on cancer cells function in E-selectin-mediated metastasis. Recently, it was reported that 6-sulfo sLeX glycans detected by the MECA-79 monoclonal antibody are expressed in roughly a quarter of gastric adenocarcinoma cases, and that these cases show a poorer prognosis than MECA-79-negative cases do. The present study was undertaken to assess expression of 6-sulfo sLeX glycans in bladder urothelial carcinoma and evaluate potential clinical implications.

MATERIALS AND METHODS:

We analyzed 78 specimens representing bladder urothelial carcinoma, as well as 4 bladder urothelial carcinoma cell lines, by immunostaining with a battery of anticarbohydrate antibodies. We also undertook an E-selectin·IgM chimera binding assay to assess E-selectin binding to 6-sulfo sLeX expressed on bladder urothelial carcinoma cells and performed reverse transcription polymerase chain reaction and complementary DNA transfection to determine which N-acetylglucosamine-6-O-sulfotransferases function in 6-sulfo sLeX biosynthesis in those cells. Finally, we performed double-immunofluorescence staining for MECA-79 and either CD3 or CD8 to evaluate potential association between high endothelial venule (HEV)-like vessels and tumor-infiltrating T lymphocytes.

RESULTS:

6-Sulfo sLeX glycans were expressed in ~20% of bladder urothelial carcinoma cases, particularly in plasmacytoid and micropapillary variants. Positive cells were also bound by E-selectin·IgM chimeras in a calcium-dependent manner. Transcripts encoding N-acetylglucosamine-6-O-sulfotransferase-2 were detected preferentially in HT-1197 bladder urothelial carcinoma cells expressing 6-sulfo sLeX, and transfection of the enzyme complementary DNA into HT-1376 cells, which do not express 6-sulfo sLeX glycans, resulted in cell surface expression of 6-sulfo sLeX. Furthermore, 6-sulfo sLeX glycans were expressed in HEV-like vessels induced in and around lymphocyte aggregates formed near carcinoma cell nests. These HEV-like vessel-associated tumor-infiltrating lymphocytes were composed primarily of CD3(+) T cells, with a fraction of CD8(+) cytotoxic T cells.

CONCLUSIONS:

Our findings indicate that 6-sulfo sLeX glycans likely play 2 roles in bladder urothelial carcinoma progression: one in lymphocyte recruitment to enhance antitumor immune responses, and the other in E-selectin-mediated tumor cell adhesion to vascular endothelial cells, which is potentially associated with metastasis.

• Authors: Minekatsu Taga, Hitomi Hoshino, Shulin Low, Yoshiaki Imamura, Hideaki Ito, Osamu Yokoyama, Motohiro Kobayashi
• Journal: Urologic oncology (Urol Oncol) Vol. 33 Issue 11 Pg. 496.e1-9 (Nov 2015) ISSN: 1873-2496 [Electronic] United States
• PMID: 26137907 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier Inc. All rights reserved.

Chemical References

• 6'-sulfated sialyl Lewis x
• E-Selectin
• Lewis X Antigen
• Oligosaccharides
• RNA, Messenger
• SELE protein, human
• Sialyl Lewis X Antigen
• Sulfotransferases
• carbohydrate sulfotransferases

Topics

• Adenocarcinoma (genetics, metabolism, secondary)
• Aged
• Aged, 80 and over
• E-Selectin (genetics, metabolism)
• Female
• Fluorescent Antibody Technique
• Follow-Up Studies
• Humans
• Immunoenzyme Techniques
• Lewis X Antigen (analogs & derivatives)
• Male
• Middle Aged
• Neoplasm Staging
• Oligosaccharides (genetics, metabolism)
• Prognosis
• RNA, Messenger (genetics)
• Real-Time Polymerase Chain Reaction
• Reverse Transcriptase Polymerase Chain Reaction
• Sialyl Lewis X Antigen (analogs & derivatives)
• Sulfotransferases (genetics, metabolism)
• Urinary Bladder Neoplasms (genetics, metabolism, pathology)