title: The analysis of N-glycolylneuraminic acid(NeuGc) of hepatoma tissue and K562 cell ferritins using HPLC and mass spectrometry.
abstract: Ferritin is an iron-storage protein and its serum level is known to increase in the patient of with inflammation and malignant tumor. To further elucidate the difference between ferritins from normal human liver tissue and that of cancer cells, their sialic acids were analyzed. The Western blot analysis and the cytochemical staining using anti-NeuGc antiserum indicated that ferritins from the human hepatocarcinoma tissue and malignant K562 cells contain NeuGc, but that from the normal liver does not. The result was also confirmed by HPLC analysis and MALDI-TOF/MS analysis of sialic acids which were derivatized by the DMB method. It was also shown that the sialic acid content in hepatocarcinoma ferritin was much higher than that in the normal liver ferritin. These results suggest that normal and cancerous liver ferritins are qualitatively and quantitatively different in sialylation. In addition, K562 cells were shown to express NeuGc even if the cells were cultured in serum-free media which lack NeuGc. This is of interest from the current concept that expression of NeuGc in human cells is due to uptake and utilization of exogenous NeuGc.
authors: Kudanzaka Hospital, Department of Internal Medicine, Tokyo, Japan .
authors: Hideo
authors: H
authors: Asakawa
authors: Kudanzaka Hospital, Department of Internal Medicine, Tokyo, Japan .
authors: Masataka
authors: M
authors: Sasabe
authors: Kudanzaka Hospital, Department of Internal Medicine, Tokyo, Japan .
authors: Ryuunosuke
authors: R
authors: Miyazaki
authors: Department of Microbiology and Hygiene, Faculty of Applied Biological Science, Hiroshima University, Hiroshima, Japan .
authors: Haruo
authors: H
authors: Matsuda
authors: Department of Patho-Physiology, Faculty of Pharmaceutical Science, Tokyo University of Science, Tokyo, Japan .
authors: Fumio
authors: F
authors: Fukai
authors: Yokohama City University, International Graduate School of Arts and Science, Kanagawa, Japan .
authors: Kazuki
authors: K
authors: Hanada
authors: Yokohama City University, International Graduate School of Arts and Science, Kanagawa, Japan .
authors: Hisashi
authors: H
authors: Hirano
authors: Division of Biochemistry, Institute of Medical Science, University of Tokyo, Tokyo, Japan .
authors: Seiichi
authors: S
authors: Takasaki
keywords: HPLC; Hepatoma; K562 cell; MS; WB; ferritin