Department of Genetics, Saint Savvas Hospital, Athens, Greece.
J Neurooncol. 2013 Jul;113(3):353-8. doi: 10.1007/s11060-013-1131-5. Epub 2013 Apr 24.
Low grade astrocytomas are the most common brain tumor in children. Recent studies have identified alterations in the BRAF serine/threonine kinase gene that result in mitogen activated protein kinase pathway activation. Herewith, we investigated the genetic changes of BRAF in pediatric low grade gliomas and their relation to pathological findings and Ki-67 proliferation index. The results showed gene fusions between KIAA1549 and BRAF in 66.7 % of tumors. The majority involved the KIAA1549-BRAF exon 16-exon 9 variant. Fusion junction between KIAA1549 exon 15 and BRAF exon 9 was found in five tumors, in which the myxoid component was the predominant. This has not been previously reported. No significant correlation was found between specific KIAA1549 and BRAF fusion junctions and Ki-67 index. All of the samples included in this study were tested for the presence of the BRAF(V600E) mutation, and no positive sample was found.
低级别星形细胞瘤是儿童中最常见的脑肿瘤。最近的研究已经确定了 BRAF 丝氨酸/苏氨酸激酶基因的改变，导致有丝分裂原激活蛋白激酶途径的激活。在此，我们研究了 BRAF 在儿童低级别神经胶质瘤中的遗传变化及其与病理发现和 Ki-67 增殖指数的关系。结果表明，66.7%的肿瘤中存在 KIAA1549 和 BRAF 之间的基因融合。大多数涉及 KIAA1549-BRAF 外显子 16-外显子 9 变体。在五个肿瘤中发现了 KIAA1549 外显子 15 和 BRAF 外显子 9 之间的融合连接，其中黏液样成分为主要成分。这以前没有报道过。特定的 KIAA1549 和 BRAF 融合连接与 Ki-67 指数之间没有发现显著相关性。本研究中包括的所有样本均检测了 BRAF(V600E)突变的存在，未发现阳性样本。
