Abstract：
Neurofibromatosis type 1 (NF1) is a genetic disorder caused by mutation of the NF1 gene that is associated with various symptoms, including the formation of benign tumors, called neurofibromas, within nerves. Drug treatments are currently limited. The mitogen-activated protein kinase kinase (MEK) inhibitor selumetinib is used for a subset of plexiform neurofibromas (PNs) but is not always effective and can cause side effects. Therefore, there is a clear need to discover new drugs to target NF1-deficient tumor cells. Using a Drosophila cell model of NF1, we performed synthetic lethal screens to identify novel drug targets. We identified 54 gene candidates, which were validated with variable dose analysis as a secondary screen. Pathways associated with five candidates could be targeted using existing drugs. Among these, chloroquine (CQ) and bafilomycin A1, known to target the autophagy pathway, showed the greatest potential for selectively killing NF1-deficient Drosophila cells. When further investigating autophagy-related genes, we found that 14 out of 30 genes tested had a synthetic lethal interaction with NF1. These 14 genes are involved in multiple aspects of the autophagy pathway and can be targeted with additional drugs that mediate the autophagy pathway, although CQ was the most effective. The lethal effect of autophagy inhibitors was conserved in a panel of human NF1-deficient Schwann cell lines, highlighting their translational potential. The effect of CQ was also conserved in a Drosophila NF1 in vivo model and in a xenografted NF1-deficient tumor cell line grown in mice, with CQ treatment resulting in a more significant reduction in tumor growth than selumetinib treatment. Furthermore, combined treatment with CQ and selumetinib resulted in a further reduction in NF1-deficient cell viability. In conclusion, NF1-deficient cells are vulnerable to disruption of the autophagy pathway. This pathway represents a promising target for the treatment of NF1-associated tumors, and we identified CQ as a candidate drug for the treatment of NF1 tumors.
摘要：
1型神经纤维瘤病（NF1）是由NF1基因突变引起的遗传性疾病，与各种症状有关。包括良性肿瘤的形成，叫做神经纤维瘤，在神经内。药物治疗目前是有限的。丝裂原激活的蛋白激酶激酶（MEK）抑制剂司美替尼用于丛状神经纤维瘤（PNs）的一部分，但并不总是有效的，并且可能引起副作用。因此,显然需要发现靶向NF1缺陷肿瘤细胞的新药.使用NF1的果蝇细胞模型，我们进行了合成致死筛选以鉴定新的药物靶标。我们鉴定了54个候选基因,通过可变剂量分析作为二次筛选进行验证。可以使用现有药物靶向与五个候选物相关的途径。其中,氯喹（CQ）和巴弗洛霉素A1，已知靶向自噬途径，显示了选择性杀死NF1缺陷果蝇细胞的最大潜力。当进一步研究自噬相关基因时，我们发现,在30个测试基因中,有14个基因与NF1有合成致死相互作用.这14个基因涉及自噬途径的多个方面，并且可以用介导自噬途径的其他药物靶向，虽然CQ是最有效的。自噬抑制剂的致死作用在一组缺乏NF1的人Schwann细胞系中是保守的，强调他们的翻译潜力。在果蝇NF1体内模型和在小鼠中生长的异种移植NF1缺陷肿瘤细胞系中，CQ的作用也得到了保留。CQ治疗比司美替尼治疗更显著地降低了肿瘤生长。此外，CQ和司美替尼联合治疗导致NF1缺陷型细胞活力进一步降低.总之,NF1缺陷型细胞易受自噬途径破坏的影响。该途径代表了治疗NF1相关肿瘤的有希望的靶标，我们确定CQ是治疗NF1肿瘤的候选药物。
