The analysis of N-glycolylneuraminic acid(NeuGc) of hepatoma tissue and K562 cell ferritins using HPLC and mass spectrometry
The analysis of N-glycolylneuraminic acid(NeuGc) of hepatoma tissue and K562 cell ferritins using HPLC and mass spectrometry
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DOI：
10.2183/pjab.82.181
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发表时间：
2006-05-01
影响因子：
3.1
通讯作者：
Takasaki, Seiichi
中科院分区：
文献类型：
--
作者：
Asakawa, Hideo;Sasabe, Masataka;Takasaki, Seiichi
铁蛋白是一种铁储存蛋白，已知在炎症和恶性肿瘤患者血清中铁蛋白水平升高。为了进一步阐明正常人肝组织铁蛋白与癌细胞铁蛋白的区别，我们对它们的唾液酸进行了分析。Western blot分析和抗NeuGc抗血清细胞化学染色表明，来自人肝癌组织和恶性K562细胞的铁蛋白含有NeuGc，而来自正常肝脏的铁蛋白不含NeuGc。对DMB法衍生的唾液酸进行了HPLC分析和MALDI-TOF/MS分析。结果表明，肝癌铁蛋白中唾液酸的含量远高于正常肝铁蛋白。这些结果表明，正常和癌性肝铁蛋白在唾液化过程中存在定性和定量上的差异。此外，即使将K562细胞培养在缺乏NeuGc的无血清培养基中，也显示出NeuGc的表达。从目前的概念来看，NeuGc在人类细胞中的表达是由于摄取和利用外源NeuGc而引起的。
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 high er 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.