利用抗体亲和层析纯化不同转移潜能人肝癌细胞系中的高尔基体蛋白73（GP73），比较不同转移潜能人肝癌细胞系中GP73 糖基化修饰水平，为GP73 成为肝癌标志物提供依据。纯化的GP73 通过质谱鉴定后，分别进行蛋白印迹（western blot）和凝集素印迹（lectin blot）分析，比较其在不同转移潜能肝癌细胞系的糖基化修饰水平。实验发现，GP73 含有伴刀豆凝集素（ConA）、橙黄网胞盘菌凝集素（AAL）、小扁豆凝集素（LCA）和红腰果E 型凝集素（PHA-E）识别的糖型，且单位GP73 的LCA、PHA-E 识别的岩藻糖和平分型糖型含量在肝癌细胞Huh7、MHCC97L、MHCC97H、HCCLM3 中有升高趋势。研究表明，单位GP73 岩藻糖和平分型聚糖结构随肝癌细胞的转移潜能升高而增多。
In this study, Golgi protein 73 (GP73) of hepatocelluler carcinoma (HCC) cell lines with different metastatic potential was purified by antibody affinity chromatography and the purification result was confirmed by LC-MS/MS, providing more proof for GP73 as a biomarker for HCC. Purified GP73 was then analyzed using western blot and lectin blot to obtain its glycosylation level in HCC cell lines with different metastatic potential. We found that glycan of GP73 can be recognized by ConA, AAL, LCA and PHA-E lectins, while the LCA and PHA-E-reactive fraction of GP73 was increased along with the increasing metastatic potential of HCC cell lines. The glycan level of GP73 was different in HCC cell lines with different metastatic potential, and the content of fucose (recognized by LCA) and bisecting structure (recognized by PHA-E) increased in agreement with the metastatic potential.
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