Patent ID: 7622261

Claim:
A method for diagnosing colon cancer by measuring extent of β1,6 N-acetylglucosamine glycosylation and expression of prostate-derived factor (PDF) protein related to tumorigenesis and metastasis, comprising: adhering antibodies against said PDF protein to two matrices, wherein one matrix is for analyzing expression of said PDF protein and the other is for analyzing extent of β1,6 N-acetylglucosamine glycosylation of said same PDF protein; adding a blood or serum sample from a patient to the two matrices to induce a first reaction; washing the matrices; one adding biotin-labeled antibodies against said PDF protein to the one matrix for analyzing expression of said PDF protein and adding biotin-labeled L4-PHA to the other matrix for analyzing extent of β1,6 N-acetylglucosamine glycosylation of said same PDF protein to induce a second reaction; washing the matrices; adding a coloring enzyme- or fluorescent substance-conjugated avidin to both matrices to induce a third reaction; washing the matrices; measuring optical density or detecting fluorescence; and comparing the expression of said PDF protein and the extent of β1,6 N-acetylglucosamine glycosylation of said same PDF protein between the blood or serum sample and a control sample, wherein an increase in the expression of said PDF protein and the extent of β1,6 N-acetylglucosamine glycosylation of said same PDF protein in the blood or serum sample relative to the control sample indicates the presence of colon cancer.