Identification of Core Proteins Carrying the Sialyl Lewis a Epitope in Pancreatic CancersYoshitoshi Hirao1, Satoshi Ogasawara1, Akira Togayachi1, Yu-ki Matsuno1, Makoto Ocho1, Keishi Yamashita2, Masahiko Watanabe2, Shoji Nakamori3, Yuzuru Ikehara1 and Hisashi Narimatsu1*
- *Corresponding Author:
- Hisashi Narimatsu
AIST Tsukuba Central 2, 1-1-1 Umezono
Tsukuba, Ibaraki 305-8568, Japan
E-mail: [email protected]
Received date: November 30, 2011; Accepted date: March 16, 2012; Published date: March 23, 2012
Citation: Hirao Y, Ogasawara S, Togayachi A, Matsuno Y, Ocho M, et al. (2012) Identification of Core Proteins Carrying the Sialyl Lewis a Epitope in Pancreatic Cancers. J Mol Biomark Diagn 2:124. doi:10.4172/2155-9929.1000124
Copyright: © 2012 Hirao Y , et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Identification of core proteins carrying the CA19-9 (carbohydrate antigen, sialyl Lewis a) epitope from various tissues will improve the diagnosis of pancreatic cancer in terms of specificity and sensitivity. In this study, we attempted to identify sialyl Lewis a-carrier proteins specifically expressed in pancreatic cancer. Pancreatic cancer is difficult to detect in the early stages of the disease, resulting in a high level of mortality. Therefore, in order to determine the correct course of treatment, it is vital to distinguish cancer from obstruction of the bile duct or other diseases. Our strategy to identify the carrier proteins was as follows: glycoproteins carrying sialyl Lewis a antigen were enriched from pancreatic cancer cell lines using anti-sialyl Lewis a antibody and then subjected to Peptide Mass Fingerprinting analysis. Based on these studies we identified nine glycoproteins carrying the sialyl Lewis a epitope. We evaluated candidate molecules by biochemical analyses of culture supernatants and human sera. In particular, we focused on one candidate molecule carrying a sialyl Lewis a epitope, Galectin-3BP/MAC2BP; M2BP, which was analyzed in detail. These results verified that our candidate molecule is a core protein carrying the sialyl Lewis a epitope. Furthermore, we demonstrated sandwich ELISA, which showed that the glycoprotein was able to detect CA19-9 antigen in culture supernatants. Our approach facilitated the identification of the core protein carrying the sialyl Lewis a epitope. We believe our approach will enable future developments in cancer glycobiomarker identification.