Study On Expression Of Melanoma Antigen Genes In Gastric Carcinom

Objective As a human tumor-specific antigen that can be recognized by CTL, MAGE gene family has high expression rate in various tumor tissues and its product of gene expression has good tumor-specificity, which makes it a hot spot of research at present. We studied the expression of MAGE-1,-2 and -3 genes in 30 samples of human gastric carcinomas and the association between the expressions and differentiation, as well as the expressions and clinical stage, trying to lay the theoretical and experimental foundation for using these genes products as the vaccine to perform immunotherapy on patients of gastric carcinoma. Methods The expression of MAGE-1,-2 and -3 genes in 30 gastric carcinomas specimens and 30 corresponding adjacent normalgastric tissue specii .ens was detected by a reverse transcriptase-----polymerase chain reaction (RT-PCR). The results were analyzed according to clinico-pathologic factors of the tumor. The 6 samples of RT-PCR products were sequenced. Results MAGE genes family has high expression rate in gastric carcinoma. 20(66.7%) of the 30 gastric carcinomas specimens expressed at least one of the MAGE mRNA, of which 14 specimens expressed MAGE-1 mRNA. 9 specimens expressed MAGE-2 mRNA, and 11 specimens expressed MAGE-3 mRNA, with the positive rates being 46.7%. 30.0%, and 36.7% respectively. There was no significant statistic difference between the expression of these three MAGE genes( x 2= 1.796, P=0.407>0.05). There was no expression of these three MAGE genes in the adjacent tissue of gastric carcinoma. There was marked significant statistic difference between the expression rates of the three MAGE genes in tissue of carcinoma and those in the adjacent tissue( x 2=8.366-18.261. P=0.0001 - 0.0038 < 0.01).The expression of MAGE genes in the 30 gastric carcinoma was notassociated with the pathological differentiation or clinical stages of the gastric carcinomas. The DNA sequence confirmed that the target gene fragment in the 4 samples of RT-PCR products were MAGE-1 ,-2 or-3 gene cDNA. Conclusion The total expression rate of MAGE-1, 2, and 3 genes in 30 specimens of gastric carcinoma was 66.7% and there was no expression of these genes in the corresponding adjacent tissue, which indicates that MAGE genes have high expression rates in tissue of gastric carcinoma and the expression is highly specific. The expression rates of MAGE genes are not related to the pathological differentiation or clinical stages of gastric carcinomas. The specific expression of MAGE genes in tissue of gastric carcinomas makes it possible to perform immunotherapy on patients of gastric carcinomas utilizing the gene coded proteins as vaccine.