Department of Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
Department of Neurological Surgery, University of Illinois at Chicago, Chicago, IL, USA.
Acta Neuropathol Commun. 2019 May 15;7(1):75. doi: 10.1186/s40478-019-0727-1.
Diffuse intrinsic pontine glioma (DIPG), an infiltrative, high grade glioma (HGG) affecting young children, has the highest mortality rate of all pediatric cancers. Despite treatment, average survival is less than twelve months, and five-year survival under 5%. We previously detected increased expression of Tenascin-C (TNC) protein in DIPG cerebrospinal fluid and tumor tissue relative to normal specimens. TNC is an extracellular matrix (ECM) glycoprotein that mediates cell-matrix interactions, guides migrating neurons during normal brain development and is thought to maintain the periventricular stem cell niche in the developing brain. Tumor TNC expression is reported in adult glioma and other cancers. However, the pattern and effects of TNC expression in DIPG has not been previously explored. Here, we characterize TNC expression in patient derived pediatric supratentorial HGG (n = 3) and DIPG (n = 6) cell lines, as well as pediatric glioma tumor (n = 50) and normal brain tissue specimens (n = 3). We found tumor specific TNC gene and protein overexpression that directly correlated with higher tumor grade (WHO III and IV, p = 0.05), H3K27 M mutation (p = 0.012), shorter progression free survival (p = 0.034), and poorer overall survival (0.041) in association with these factors. TNC knockdown via lentiviral shRNA transfection of HGG (n = 1) and DIPG (n = 3) cell lines resulted in decreased cell proliferation, migration, and invasion in vitro (p < 0.01), while TNC cDNA transfection resulted in increased cell migration, invasion and proliferation (p < 0.01) as well as altered cell morphology in H3K27 M mutant DIPG lines. Whole transcriptome sequencing analysis (RNA-Seq) on DIPG (n = 3) and HGG (n = 2) cell lines after TNC cDNA, shRNA, and empty vector control transfection revealed the effects of TNC expression level on global gene expression profiles. Together, our findings reveal TNC expression in DIPG in association with H3K27 M mutation and VEGF signaling, and suggest that TNC may contribute to DIPG tumor phenotype, and serve as a clinically detectable biomarker for DIPG.
弥漫内生型脑桥胶质瘤（DIPG）是一种浸润性高级别神经胶质瘤（HGG），主要影响儿童，是所有儿科癌症中死亡率最高的。尽管进行了治疗，平均存活时间不到 12 个月，五年存活率低于 5%。我们之前发现 DIPG 患者的脑脊液和肿瘤组织中 Tenascin-C（TNC）蛋白的表达增加，与正常标本相比。TNC 是一种细胞外基质（ECM）糖蛋白，可介导细胞-基质相互作用，在正常大脑发育过程中指导迁移神经元，并被认为可维持发育中大脑的脑室下干细胞巢。在成人胶质瘤和其他癌症中也有报道肿瘤 TNC 的表达。然而，DIPG 中 TNC 表达的模式和影响尚未得到探索。在这里，我们对源自患者的儿童幕上 HGG（n=3）和 DIPG（n=6）细胞系，以及儿童脑肿瘤（n=50）和正常脑组织标本（n=3）中的 TNC 表达进行了特征描述。我们发现肿瘤特异性 TNC 基因和蛋白过表达与更高的肿瘤分级（WHO III 和 IV，p=0.05）、H3K27M 突变（p=0.012）、较短的无进展生存期（p=0.034）和较差的总生存期（0.041）直接相关。通过慢病毒 shRNA 转染对 HGG（n=1）和 DIPG（n=3）细胞系进行 TNC 敲低导致体外细胞增殖、迁移和侵袭减少（p<0.01），而 TNC cDNA 转染导致细胞迁移、侵袭和增殖增加（p<0.01）以及 H3K27M 突变 DIPG 系细胞形态改变。对 DIPG（n=3）和 HGG（n=2）细胞系进行 TNC cDNA、shRNA 和空载体对照转染后的全转录组测序分析（RNA-Seq）显示了 TNC 表达水平对全局基因表达谱的影响。总之，我们的发现揭示了 DIPG 中与 H3K27M 突变和 VEGF 信号相关的 TNC 表达，并表明 TNC 可能有助于 DIPG 肿瘤表型，并可作为 DIPG 的临床可检测生物标志物。
