黑色素瘤相关抗原家族新基因restin的组织表达谱

Tissue Expression of Human Restin,a Novel Member of Melanoma Associated Antigen Family

Restin是从维甲酸诱导肿瘤分化细胞中克隆的一种黑色素瘤相关抗原家族(MAGE)的新成员.对该基因在不同组织、不同细胞系的表达水平进行研究,将有利于揭示其生物学功能.使用α3-2P-dCTP标记人restin编码区基因作为探针,针对12种不同成人组织mRNA的Multiple TissueNorthern(MTN)膜和含76种成人、胎儿及常用细胞系mRNA的Multiple Tissue Expression(MTE)Array膜进行杂交分析,同时利用地高辛标记探针对11种常见肿瘤组织进行原位杂交检测.结果显示,MTN膜杂交中,12种组织显示均一杂交条带,约1.8 kb,提示该基因可能不存在剪接变异体;MTE膜杂交中,正常组织中均有不同程度的表达,但在肿瘤细胞系中均低表达或者不表达;原位杂交的结果显示,在8种恶性肿瘤组织中均不表达,而在3种良性肿瘤组织中呈现较低的表达.结果提示,该基因在正常组织中的表达明显高于肿瘤组织和肿瘤细胞系,完全不同于其它MAGE-A、B、C的组织表达方式.结合该基因在维甲酸诱导分化的肿瘤细胞中高表达,推测restin可能与正常细胞的分化、增殖有关.

Restin, isolated from tumor differentiation cell induced by ATRA, is the novel member of MACE （melanoma antigen encoding gene） family. To obtain some clues of its biological function, this work is going to investigate the restin expression level in variety of tumors and cells. Using the code region of restin labeled with α-^32P-dCTP as a probe, the mRNA expression of restin was examined in multiple tissue northern（MTN） blot membrane and multiple tissue express （MTE）array by Northern blot and dot blot hybridization, respectively. The mRNA expression of restin was examined by in situ hybridization with restin probe labeled with dig in 11 tumor tissues. Northern blot showed that all 12 normal tissues displayed hybrid bands with same location, approximately 1.8 kb. These results suggested that the restin mRNA could not present some splicing variants. Dot blot showed that the restin high expressed in all normal tissues, but less or not expressed in tumor cell lines. In 11 tumor tissues, 8 malignant tumors displayed no expression, but 3 benign tumors displayed lower expression. These results suggested that human restin was rarely expressed in cancer ceil lines, tumor tissues and but ubiquitously expressed in many normal tissues. These results were quite different from the expression of other MAGEs, such as MAGE-A, B, and C. Considering the inducible expression of restin in tumor tissues by ATRA, we deduced that the restin was possibly to be a regulator of cell proliferation and differentiation.