黑色素瘤抗原-1基因在肝细胞癌中的表达

目的 检测黑色素瘤抗原－１（ＭＡＧＥ－１）ｍＲＮＡ在肝细胞癌（ＨＣＣ）中的表达，为用ＭＡＧＥ－１基因编码蛋白作为疫苗对ＨＣＣ患者进行免疫治疗提供依据。方法 用逆转录－聚合酶链反应（ＲＴ－ＰＣＲ）方法对４５例ＨＣＣ患者组织和相应癌旁肝组织以及１６例肝硬化组织和１２例正常肝组织的ＭＡＧＥ－１ｍＲＮＡ表达情况进行了研究，对６例ＲＴ－ＰＣＲ扩增产物的目的基因片段进行ＤＮＡ序列测定，并以测序证实为ＭＡＧＥ－

Expression of MAGE-1 gene in hepatocellular carcinoma

OBJECTIVE: To investigate the expression of MAGE-1 mRNA in human hepatocellular carcinoma (HCC) and to discuss the possibility of using MAGE-1 antigens as a new peptide vaccine for immunotherapy for HCC. METHODS: The expression of MAGE-1 mRNA in HCC tissue and the adjacent non-HCC liver tissue was detected using RT-PCR in 45 samples of HCC, 16 samples of cirrhosis and 12 samples of normal liver tissue. The 6 samples of MAGE-1 mRNA positive PCR products were DNA sequenced. The sequenced fragments of MAGE-1 cDNA were used as template to which a alpha 32P] labeled probe was synthesized and employed for Southern blot analysis. HLA class I-A and I-B typing of 43 HCC patients were assayed by ELISA test. RESULTS: Of the 45 HCC samples, 32 expressed MAGE-1 mRNA. None of the HCC adjacent tissue or liver tissue from cirrhosis or normal liver samples expressed MAGE-1 mRNA. The DNA sequence confirmed that the target gene fragment in all the 6 samples of PCR products was MAGE-1 cDNA. Point mutation occurred in 3 samples resulting in alternation of amino acid residues in 2 positions. Southern blot analysis showed that MAGE-1 was also detectable in HCC tissue which was MAGE-1 positive in RT-PCR assay, but not detectable in non-HCC liver tissue. In HCC patients, the predominant types of HLA were A2(53.5%), A11(25.6%), A24(20.9%), A33(20.9%), B13 (28.3%) and B35(23.2%). MAGE-1 mRNA expression in HCC showed no correlation with the level of alpha-FP in blood and the diameter of tumor. CONCLUSIONS: MAGE-1 mRNA is expressed at a high percentage of HCC samples. This tumor rejection antigen may have potential to be used as a new peptide vaccine for immunotherapy for HCC. There are point mutations of MAGE-1 gene sequence in some Chinese HCC patients.