黑色素肿瘤抗原基因-1、3在直肠癌的表达及其意义

Expression of melanoma antigen-1, 3 gene in rectal cancer and their clinical significance

目的检测黑色素肿瘤抗原基因-1、3（MAGE-1、MAGE-3）在直肠癌中的表达，探讨其与直肠癌临床病理的关系及其在直肠癌免疫治疗中的应用价值。方法采用RT—PCR法，对33例直肠癌患者的癌组织及其相应的癌旁组织和手术切缘（乙状结肠端）以及3例直肠息肉标本（无瘤）的MAGE-1、MAGE-3的表达情况进行检测，并对RT—PCR扩增产物中的目的基因片段进行DNA测序验证。结果33例直肠癌组织中，MAGE-1基因的表达阳性率为30．30％（10／33），MAGE-3基因的表达阳性率为42．42％（14／33），MAGE-1、MAGE-3均表达的阳性率为21．21％（7／33），至少表达其中-种的阳性率为51．51％；在癌旁组织和手术切缘组织中，MAGE-1基因的表达阳性率均为12．12％（4／33），MAGE-3基因的表达阳性率分别为18．18％（6／33）、15．15％（5／33）；3例直肠息肉标本未见MAGE-1、MAGE-3表达。肿瘤组织MAGE-1、MAGE-3基因表达阳性率均显著高于癌旁组织和手术切缘组织（P〈0．05）；而与患者年龄、性别、肿瘤组织学类型、Duke分期及淋巴结转移无关（P〉0．05）。结论基于MAGE-1、MAGE-3基因在直肠癌中的高表达率，MAGE-1、MAGE-3表达蛋白可以作为一种有前途的靶点用于免疫治疗，同时有望成为一种筛查和随访指标。

Objective To detect the expression of melanoma antigen-1 gene （MAGE-1）,melanoma antigen-3 gene （MAGE-3） and explore their clinical significance. Methods The expression of MAGE-1 and MAGE-3 in central tumor tissue, para-tumorous normal mucosa and tissue of resection-border were detected by RT-PCR. Results The expression of MAGE-1 was positive in 10 out of 33 （30.30 %） cases of rectal cancer, 4 out of 33 cases （12.12%） and 4 out of 33 cases （12.12 %） in para-tumorous normal mucosa and tissue of resection-border respectively; the expression of MAGE-3 was positive in 14 out of 33（42.42 %） cases of rectal cancer, 6 out of 33 cases （18.18 % ） and 5 out of 33 cases （15.15 %） in para-tumorous normal mucosa and tissue of resection-border respectively; 7 out of 33 cases （21.21%） was expressed MAGE-1 and MAGE-3 simutaneously; 17 out of 33 cases （51.51%） was expressed at least one of MAGE-1 and MAGE-3; the positive rates of MAGE-1 or MAGE-3 in center tumor tissue were significant higher than those of its para-tumorous and resection-border （P 〈0.05）. The expression of MAGE-1 or MAGE-3 was not related to age, sex, histological grades, metastasis to lymph nodes, duke stages （P 〉0.05）. Conclusion As their significance, MAGE-1, MAGE-3 protein may be used as a target molecule of immunotherapy for rectal cancer and indexes for follow-up study of rectal cancer as well.