α-地中海贫血/精神发育迟滞综合征X染色体相关基因的表达及1p/19q遗传学改变在星形细胞瘤、少突胶质细胞瘤及少突星形细胞瘤诊断中的意义

Significance of expression of IDH-1, ATRX and molecular genetic alterations of chromosome 1p/19q in diagnosis of astrocytoma, oligodendroglioma and oligoastrocytoma

目的探讨a-地中海贫血/精神发育迟滞综合征X染色体相关基因(ATRX)的表达及1p/19q遗传学改变在星形细胞瘤、少突胶质细胞瘤及少突星形细胞瘤诊断中的意义。方法星形细胞瘤、少突胶质细胞瘤及少突星形细胞瘤共53例,采用免疫组化及荧光原位杂交技术检测ATRX的表达及染色体1p/19q分子遗传学改变。结果星形细胞瘤、少突胶质细胞瘤及少突星形细胞瘤中ATRX突变率(ATRX表达为阴性)分别为60.0%、44.4%及50.0%;星形细胞瘤染色体1p及19q单缺失和1p/19q共缺失率均为0%,少突胶质细胞瘤缺失率分别为54.5%、0%和45.5%,少突星形细胞瘤缺失率分别为12.5%、0%和0%,少突胶质细胞瘤染色体1p/19缺失率(包括共缺失及单缺失)与非少突胶质细胞肿瘤(包括星形细胞瘤及少突星形细胞瘤)比较差异有统计学意义(P=0.032)。联合检测ATRX表达及1p/19q缺失情况,少突星形细胞瘤与星形细胞瘤及少突胶质细胞瘤比较差异有统计学意义(P=0.046,P=0.003)。结论染色体1p/19q缺失主要发生在少突胶质细胞瘤中,对少突胶质细胞瘤的诊断具有重要价值;少突星形细胞瘤与星形细胞瘤的遗传学分子改变具有一定的差异性。

Objective To explore the expression of a-Thalassemia/Mental Retardation Syndrome X-linked （ATRX） and molecular genetic alterations of chromosome lp/19q in diagnosis of astrocytoma, oligodendroglioma and oligoastrocytoma. Methods We analyzed ATRX expression status by immunohistochemistry in 53 patients with astrocytoma, oligodendrogliorna or oligoastrocytoma.The molecular genetic alterations of chromosome 1p/19q with fluorescence in situ hybridization in these tumors were analyzed. Results The mutation rate of ATRX in astrocytoma, oligodendroglioma or oligoastrocytoma were 60.0%, 44.4%, 50.0%; The loss rates of chromosome lp, 19q and 1p/19q were0%, 0%, 0% in astrocytoma; 54.5%, 0%, 45.5% in oligoder^droglioma and 12.5%, 0%, 0% in oligoastrocytoma respectively, with significant differences between oligodendroglioma and non-oligodendroglioma （P=0.032）. Conjoint analysis of ATRX mutation and loss rates of chromosome lp, 19q and 1p/19q status defined 3 subtypes of gliomas, with significant difference （P=0.046, P=0.003）. Conclusions The loss of lp/19q is mainly occurred in oligodendroglioma, which can be used as a oligodendroglioma marker in diagnosis. There are significant differences between astrocytoma and oligoastrocytoma about the molecular genetic alterations.