Gastrointestinal (GI)
cancers constitute the largest portion of all human
cancers, and the most prevalent GI
cancers in China are
colorectal cancer (CRC),
gastric cancer (GC), and
hepatocellular carcinoma (HCC). Exosomes are nanosized vesicles containing
proteins,
lipids,
glycans, and
nucleic acid, which play important roles in the tumor microenvironment and progression. Aberrant glycosylation is closely associated with GI
cancers; however, little is known about the glycopattern of the exosomes from GI
cancer cells. In this study, glycopatterns of HCC, CRC, and GC cell lines and their exosomes were detected using
lectin microarrays. For all exosomes, (GlcNAcβ1-4)n and Galβ1-4GlcNAc (DSA) were the most abundant
glycans, but αGalNAc and αGal (GSL-II and SBA) were the least. Different
cancers had various characteristic
glycans in either cells or exosomes.
Glycans altered in cell-derived exosomes were not always consistent with the host cells in the same
cancer. However, Fucα1-6GlcNAc (core
fucose) and Fucα1-3(Galβ1-4)GlcNAc (AAL) were altered consistently in cells and exosomes although they were decreased in HCC and CRC but increased in GC. The study drew the full-scale
glycan fingerprint of cells and exosomes related to GI
cancer, which may provide useful information for finding specific
biomarkers and exploring the underlying mechanism of glycosylation in exosomes.