Mokhtari K, Paris S, Aguirre-Cruz L, Privat N, Crinière E, Marie Y, Hauw J-J, Kujas M, Rowitch D, Hoang-Xuan K, Delattre J-Y, Sanson M
Laboratoire de neuropathologie R Escourolle (Pr Hauw), Universite Pierre et Marie Curie, Paris, France.
Neuropathol Appl Neurobiol. 2005 Feb;31(1):62-9. doi: 10.1111/j.1365-2990.2004.00612.x.
The expression of Olig2, a basic helix-loop-helix (bHLH) transcription factor involved in oligodendroglial specification, was investigated by immunohistochemistry in a series of 146 tumours and control samples. Olig2 expression was restricted to glial tumours and nontumoral oligodendrocytes. It was higher in oligodendrogliomas as compared to astrocytomas and oligoastrocytomas, and in grade III as compared to grade II tumours. Olig 2 was absent or weakly expressed in glioblastoma (GBM), whereas strong expression was found in the oligodendroglial foci of GBM with oligodendroglial component (GBMO). Double labelling was performed on a subset of the most typical tumours, according to the WHO classification. It showed a mutual exclusion, at cell level, of Olig2 and GFAP expression. In pure oligodendrogliomas, tumour cells were Olig2+/GFAP-. In contrast, two main tumour populations, Olig2+/GFAP- and Olig2-/GFAP+, were found in both oligoastrocytomas and astrocytomas. Based on these data from selected samples, two separate entities can be established, corresponding to 'pure oligodendrogliomas' and 'astrocytomas and oligoastrocytomas'. The relevance of this subdivision is further supported by the association with 1p loss and a trend to better survival for pure oligodendrogliomas and with p53 expression and a trend to shorter survival for astrocytomas and oligoastrocytomas. Combined testing of Olig2, 1p status, GFAP and p53 expression may therefore be helpful in refining current classification and providing more homogeneous sets of gliomas for clinical studies.
通过免疫组织化学方法，在146例肿瘤及对照样本中研究了少突胶质细胞特异性相关的碱性螺旋-环-螺旋（bHLH）转录因子Olig2的表达情况。Olig2表达仅限于神经胶质瘤和非肿瘤性少突胶质细胞。与星形细胞瘤和少突星形细胞瘤相比，少突胶质细胞瘤中的Olig2表达更高；与II级肿瘤相比，III级肿瘤中的Olig2表达更高。胶质母细胞瘤（GBM）中Olig2缺失或弱表达，而在具有少突胶质细胞成分的胶质母细胞瘤（GBMO）的少突胶质细胞灶中发现强表达。根据世界卫生组织（WHO）分类，对一部分最典型的肿瘤进行了双重标记。结果显示，在细胞水平上，Olig2和GFAP表达相互排斥。在纯少突胶质细胞瘤中，肿瘤细胞为Olig2+/GFAP-。相反，在少突星形细胞瘤和星形细胞瘤中均发现了两个主要的肿瘤群体，即Olig2+/GFAP-和Olig2-/GFAP+。基于这些选定样本的数据，可以确定两个独立的实体，分别对应于“纯少突胶质细胞瘤”和“星形细胞瘤及少突星形细胞瘤”。这种细分的相关性进一步得到以下证据的支持：纯少突胶质细胞瘤与1p缺失相关且生存趋势较好，星形细胞瘤和少突星形细胞瘤与p53表达相关且生存趋势较短。因此，联合检测Olig2、1p状态、GFAP和p53表达可能有助于完善当前分类，并为临床研究提供更同质化的胶质瘤组。
