低级别胶质肿瘤的1p/19q缺失研究

Loss of 1p/19q in Low Grade Glioma

背景与目的:近几年来,少枝胶质细胞瘤,特别是有染色体1p/19q的联合缺失者被证实对烷化剂化疗敏感,成为预后良好的标志物。本实验旨在研究低级别胶质瘤中1p/19q的联合缺失率和与标本中1p/19q的缺失百分比相关的分子病理特征。方法:搜集北京天坛医院低级别胶质瘤标本25例,应用免疫荧光原位杂交(fluorescence in situ hybridization,FISH)的方法对1p36和19q13的缺失程度进行定量分析,统计其在低级别胶质瘤中的联合缺失率,并应用Spearman秩相关分析方法分析标本中1p36、19q13缺失百分比与P170、MGMT、MMP-9、PTEN、EGFR、P53、VEGF、Ki-67、TOPO-Ⅱ、GST-π的分子病理结果的关系。结果:在25例低级别胶质瘤标本中,星形细胞瘤10例,少枝胶质细胞瘤3例,少枝星形细胞瘤12例。在星形细胞瘤、少枝胶质瘤和少枝星形细胞瘤中,1p/19q联合缺失率分别为40%、67%和50%。1p36、19q13的缺失程度与MGMT表达呈负相关,(P分别为0.042和0.015),1p36的缺失程度与GST-π表达呈负相关(P=0.024)。结论:在低级别胶质瘤中,1p/19q的联合缺失率与国外报道相似,MGMT、GST-π的低表达可能与1p、19q的缺失有关。

BACKGROUND ＆ OBJECTIVE： Oligodendrogliomas, particularly those that have chromosomal loss of combined 1p/19q, have been reported to be sensitive to alkylator chemotherapy. So combing 1p/19q is thought to be a prognostic marker for longer survival. In this article, the incidence of eombining 1p/19q loss in low grade glioma and the molecular pathological features correlated with the extent of 1p/19q loss were studied. METHODS：We collected 25 low grade gliomas in Beijing Tiantan Hosptal and studied the percentage of 1p/19q loss in every specimen by Fluorescence in situ hybridization method. The incidence of 1p/19q loss and the molecular pathological features correlated with the percentage of 1p/19q loss in every specimen were analyzed. RESULT： Ten astrocytomas, 3 oligodendrogliomas and 12 oligoastroeytomas were collected. Combining loss of 1p/19q was found in 40% of astroeytoma, 67% of oligodendroglioma and 50% of oligoastroeytoma, respectively. In low grade gliomas, the percentage of 1p/19q loss in every specimen was negatively correlated with MGMT expression and lp loss was negatively correlated with GST-π expression. CONCLUSIONS： In low grade gliomas, the incidence of combining loss of 1p/19q is similar with that in literatures. Low expression of MGMT and GST-π may be associated with loss of 1p/19q.