Aberrant glycosylation has been observed in many types of cancer, but the mechanism of glycosylation change is still poorly understood. To elucidate relationships between glycosylation and colon cancer progression, we analyzed glycosylation status of b-haptoglobin (b-Hp) obtained from 46 cancer patients, 14 inflammatory bowel disease patients and 38 normal subjects. Aleuria aurantia lectin reactivity with cancer b-Hp was much higher than in the other two study groups. These results were confirmed by lectin blotting and microarray assay using other lectins directed to fucosyl residues. Levels of such glycans were correlated with stage of colon cancer progression. Reactivity with fucosylated glycans was eliminated by treatment with a1-3/ 4 fucosidase but not a1-6 fucosidase, indicating that enhanced lectin reactivity with the fucose moiety of colon cancer b-Hp is due to Fuca1-3/4GlcNAc. Moreover, site-specific glycan occupancy was determined by sequential LC/MS analysis. Mass spectrometric analysis showed that fucosylation of b-Hp was higher in colon cancer patients than in other subjects. In particular, fucosylation at Asn 241 of b-Hp in sera of colon cancer patients was clearly higher than in the other groups, and the ratio of fucosylated glycopeptides containing Asn 241 decreased greatly after treatment with a1-3/4 fucosidase. In conclusion, the level of a1-3/4 fucosyl epitope at Asn 241 of b-Hp is potentially useful as a novel marker for colon cancer.

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γ-Oryzanol, a mixture of ferulic acid esters of triterpene alcohols and sterols, is a nutritionally important group of rice secondary metabolites. A library of 27 γ-oryzanol was assembled from existing data and used to assist identification and quantification of γ-oryzanol isolated from 16 Korean rice varieties (11 white and 5 pigmented). γ-Oryzanol was analyzed with liquid chromatography with diode array detection and electrospray ionization mass spectrometry. Nineteen different γ-oryzanol were observed and identified as stigmasterol, campesterol and sitosterol or common and hydroxylated triterpene alcohols. In the 16 varieties, the total γ-oryzanol content averaged 43.8 mg/100 g (range, 26.7-61.6 mg/100 g), which Josaengheugchal exhibited the highest level (61.6 mg/100 g). The Korean rice varieties were classified based on qualitative and quantitative γ-oryzanol data by multivariate statistical analysis. Clusters of specialty rice varieties exhibited higher γ-oryzanol levels than those of common rice varieties.