Lorenzi Federica, Jostes Sina, Gao Qiong, Hutchinson J Ciaran, Tall Jennifer, Martins da Costa Barbara, Cooke Anisha J, Rampling Dyanne, Ogunbiyi Olumide, Barker Karen, Hughes Debbie, Barone Giuseppe, Barisa Marta, Bellini Angela, Hubank Michael, Schleiermacher Gudrun, Anderson John, Bernstein Emily, Chesler Louis, George Sally L
Division of Clinical Studies, The Institute of Cancer Research, 15 Cotswold Road, Sutton, SM2 5NG, London, United Kingdom.
Department of Oncological Sciences, Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, 10029-5674, USA.
Cancer Lett. 2025 Mar 31;613:217495. doi: 10.1016/j.canlet.2025.217495. Epub 2025 Jan 30.
ATRX is one of the most frequently mutated genes in high-risk neuroblastoma. ATRX mutations are mutually exclusive with MYCN amplification and mark a recognizable patient subgroup, presenting in older children with chemotherapy-resistant, slowly progressive disease. The mechanisms underlying how ATRX mutations drive high-risk and difficult-to-treat neuroblastoma are still largely elusive. To unravel the role of ATRX in neuroblastoma, we generated isogenic neuroblastoma cell line models with ATRX loss-of-function and ATRX in-frame multi-exon deletions, representing different types of alterations found in patients. RNA-sequencing analysis consistently showed significant upregulation of inflammatory response pathways in the ATRX-altered cell lines. In vivo, ATRX alterations are consistently associated with macrophage infiltration across multiple xenograft models. Furthermore, ATRX alterations also result in upregulation of epithelial-to-mesenchymal transition pathways and a reduction in expression of adrenergic core-regulatory circuit genes. Consistent with this, bioinformatic analysis of previously published neuroblastoma patient data sets revealed that ATRX-altered neuroblastomas display an immunogenic phenotype and higher score of macrophages (with no distinction between M1 and M2 macrophage populations) and dendritic cells, but not lymphocytes. Histopathological assessment of diagnostic samples from patients with ATRX mutant disease confirmed these findings with significantly more macrophage infiltration compared to MYCN-amplified tumors. In conclusion, we show that gene expression and cell-state changes as a result of ATRX alterations associate with a characteristic immune cell infiltration in both in vivo models and patient samples. Together, this provides novel insight into mechanisms underlying the distinct clinical phenotype seen in this group of patients.
ATRX是高危神经母细胞瘤中最常发生突变的基因之一。ATRX突变与MYCN扩增相互排斥，并标记出一个可识别的患者亚组，该亚组出现在年龄较大的儿童中，患有化疗耐药、进展缓慢的疾病。ATRX突变驱动高危和难治性神经母细胞瘤的潜在机制在很大程度上仍然不清楚。为了阐明ATRX在神经母细胞瘤中的作用，我们构建了具有ATRX功能丧失和ATRX框内多外显子缺失的同基因神经母细胞瘤细胞系模型，这些模型代表了在患者中发现的不同类型的改变。RNA测序分析一致显示，在ATRX改变的细胞系中炎症反应途径显著上调。在体内，在多个异种移植模型中，ATRX改变始终与巨噬细胞浸润相关。此外，ATRX改变还导致上皮-间质转化途径上调，以及肾上腺素能核心调节回路基因表达降低。与此一致的是，对先前发表的神经母细胞瘤患者数据集的生物信息学分析表明，ATRX改变的神经母细胞瘤表现出免疫原性表型，巨噬细胞（M1和M2巨噬细胞群体无区别）和树突状细胞得分较高，但淋巴细胞得分不高。对ATRX突变疾病患者诊断样本的组织病理学评估证实了这些发现，与MYCN扩增肿瘤相比，巨噬细胞浸润明显更多。总之，我们表明，ATRX改变导致的基因表达和细胞状态变化与体内模型和患者样本中的特征性免疫细胞浸润相关。这共同为这组患者中所见独特临床表型的潜在机制提供了新的见解。
