[Expression of MAGE-B genes in hepatocellular carcinoma].

Abstract

To investigate the expression of MAGE-B genes in hepatocellular carcinoma (HCC) in order to find new targets for immunotherapy.
The expression of MAGE-B1, B2, A1 and A3 mRNA was detected using RT-PCR in HCC tissues and the corresponding adjacent non-HCC tissues from 47 HCC patients, 30 samples of cirrhosis and normal liver tissues. Four samples selected randomly from MAGE-B1 or B2 with positive RT-PCR results were sequenced to confirm the results of RT-PCR. The relationship between the expression of MAGE-B and some clinicopathological parameters was analyzed.
MAGE-B1 mRNA and MAGE-B2 mRNA were detected in 44.7% (21/47) and 61.7% (29/47) of HCC samples, respectively, while neither MAGE-B1 nor MAGE-B2 could be detected in the corresponding adjacent non-HCC liver tissues. In addition, none of 30 samples of cirrhosis and normal liver tissues was shown to express both MAGE-B genes. The DNA sequence confirmed that the RT-PCR products were truly target cDNA. The frequency of the expression of MAGE-A1 and A3 was 74.5% (35/47) and 44.7% (21/47), respectively. There was significant correlation between the expression of MAGE-B and MAGE-A (P < 0.05). However, the positive expression of MAGE-B was observed in 5 out of 12 HCC tissues without expression of MAGE-A1 and/or A3. When all four MAGE genes were examined, the positive rate of expression of one, two, three and four genes was 83.0% (39/47), 55.3% (26/47), 48.9% (23/47), and 38.3% (18/47) of 47 HCC tissues, respectively. No correlation was found between the expression of MAGE-B and clinical parameters such as age, sex, tumor size, degree of tumor differentiation, serum alpha-fetoprotein level and hepatitis B virus or hepatitis C virus infection (P > 0.05).
MAGE-B genes are expressed with relatively high frequency and specificity in HCC. Most HCC patients with positive expression of at least one member of MAGE-B or MAGE-A gene family are adequate candidates to receive specific immunotherapy. Frequent co-expression of multiple members of MAGE-B and MAGE-A subfamilies provides the possibility of using polyvalent vaccines to achieve more effective immunotherapeutic results.