Mutation analysis of tumors in ophthalmological area to to choose the treatment modalities---mutation analysis using paraffin specimens---

目的：探讨基因突变分析和基因型分析在眼科肿瘤诊断中的应用价值。靶基因为TGF-β和免疫球蛋白轻链。方法：[突变分析]检测TGF-β II型受体（T β R2）、信号转导因子Smad 4的表达及突变。从21例恶性黑色素瘤、皮脂腺癌、鳞状细胞癌、基底细胞癌、多形性腺癌、多形性腺瘤、孤立性纤维瘤、血管瘤等患者的石蜡包埋标本中提取DNA。采用聚合酶链式反应（PCR）扩增TβR2和Smad4部分外显子编码的DNA片段，然后进行单链构象多态性分析（SSCP）检测突变。【TβR2和Smads的表达】石蜡切片免疫组化观察表达。[免疫球蛋白重排]在山形大学医院治疗3例淋巴细胞增生性病变。对手术活检标本进行组织病理学检查，并采用Southern blot杂交检测免疫球蛋白重排作为基因型分析。结果：21例患者中有2例出现SSCP引起的TβR2外显子6和smad 4外显子11a带移位。免疫组化结果显示TβR2表达降低。1例淋巴增生性肿瘤，免疫球蛋白轻链基因重排。这个病例被证明是恶性的。结论：本研究提示TGF-β相关基因突变可能与肿瘤发生有关，但可能不能用于临床诊断恶性肿瘤。免疫球蛋白轻链基因重排对恶性肿瘤的诊断有重要意义。

Purpose : To evaluate the usefulness of gene mutation analysis and genotype analysis to diagnose tumors in ophthalmological area. The target genes are TGF-β and immunoglobulin light chain.Methods : [mutation analysis] Expression and mutations of TGF-β type II receptor (T β R2), Smad 4 (one of the signal transducers) were investigated. DNA was extracted from paraffin embedded specimens from 21 patients, which included malignant melanoma, sebaceous carcinoma, squamous cell carcinoma, basal cell carcinoma, pleomorphic adenocarcinoma, pleomorphic adenoma, solitary fibrous tumor, hemangioma and others. DNA fragments which encode some exons of TβR2 and Smad4 were amplified by polymerase chain reaction (PCR), and then single strand conformation polymorphism analysis (SSCP) was performed to detect mutations. [Expression of TβR2 and Smads] Expression was observed immunohistochemically in the paraffin sections. [immunoglobulin rearrangement] Three cases of lymphoproliferative lesions were treated at Yamagata University Hospital. The surgical biopsy specimens were examined histopathologically and Southern blot hybridization was used to detect immunoglobulin rearrangement as a genotype analysis.Results : Two out of 21 cases showed the band shift of TβR2 exon 6 and smad 4 exon 11a by SSCP. The expression of TβR2 was shown to decrease by immunohistochemically. In one case of lymphoproliferative tumors, rearrangement of immunoglobulin light chain gene. This case was shown to be malignant.Conclusions : This study suggests that the mutation in TGF-β related genes may be related to the tumorigenesis, however, may not be used to diagnose malignancy clinically. The rearrangement of immunoglobulin light chain gene is very useful to diagnose malignancy.