背景:胶质母细胞瘤(GBM)是一种侵袭性脑肿瘤,表现出对当前治疗的抵抗力,使得新的治疗靶点的识别至关重要。在这种情况下,细胞朊病毒蛋白(PrPC)是新疗法的潜在候选者。由PRNP基因编码,PrPC可以在GBM中呈现增加的表达水平,影响细胞增殖,增长,迁移,入侵和干。然而,PRNP/PrPC调节GBM生物学关键方面的确切分子机制仍然难以捉摸。
方法:为了阐明PRNP/PrPC在这种癌症生物学中的意义,我们分析了来自4项独立研究的患者来源GBM的公开RNA测序(RNA-seq)数据.首先,我们将通过批量RNA-seq分析的样本排序为PRNPhigh和PRNPlow,并比较了它们的转录组景观。然后,我们分析了通过单细胞RNA-seq分析的PRNP+和PRNP-GBM细胞,以进一步了解PRNP/PrPC可能在该肿瘤中起作用的分子背景.我们探索了一个额外的蛋白质组学数据集,应用类似的比较方法,来证实我们的发现.
结果:功能分析显示,囊泡动力学特征与GBM中的PRNP/PrPC水平密切相关。我们发现了一组73个基因,富含囊泡相关途径,在所有RNA-seq数据集中,其表达水平在PRNPhigh/PRNP+细胞中增加。囊泡相关基因,发现ANXA1,RAB31,DSTN和SYPL1在患者衍生的GBM的内部集合中在体外上调。此外,患者来源样品的蛋白质组分析加强了囊泡生物发生增强的发现,PRNPhigh/PRNP+GBM细胞中的加工和运输。
结论:一起,我们的发现揭示了PrPC作为GBM中囊泡生物学的潜在调节剂的新作用,这是细胞间通讯和癌症维持的关键。我们还介绍了GBMdiscovery,一种新颖的用户友好的工具,可以研究GBM生物学中的特定基因。
BACKGROUND: Glioblastoma (GBM) is an aggressive brain tumor that exhibits resistance to current treatment, making the identification of novel therapeutic targets essential. In this context, cellular prion protein (PrPC) stands out as a potential candidate for new therapies. Encoded by the PRNP gene, PrPC can present increased expression levels in GBM, impacting cell proliferation, growth, migration, invasion and stemness. Nevertheless, the exact molecular mechanisms through which PRNP/PrPC modulates key aspects of GBM biology remain elusive.
METHODS: To elucidate the implications of PRNP/PrPC in the biology of this cancer, we analyzed publicly available RNA sequencing (RNA-seq) data of patient-derived GBMs from four independent studies. First, we ranked samples profiled by bulk RNA-seq as PRNPhigh and PRNPlow and compared their transcriptomic landscape. Then, we analyzed PRNP+ and PRNP- GBM cells profiled by single-cell RNA-seq to further understand the molecular context within which PRNP/PrPC might function in this tumor. We explored an additional proteomics dataset, applying similar comparative approaches, to corroborate our findings.
RESULTS: Functional profiling revealed that vesicular dynamics signatures are strongly correlated with PRNP/PrPC levels in GBM. We found a panel of 73 genes, enriched in vesicle-related pathways, whose expression levels are increased in PRNPhigh/PRNP+ cells across all RNA-seq datasets. Vesicle-associated genes, ANXA1, RAB31, DSTN and SYPL1, were found to be upregulated in vitro in an in-house collection of patient-derived GBM. Moreover, proteome analysis of patient-derived samples reinforces the findings of enhanced vesicle biogenesis, processing and trafficking in PRNPhigh/PRNP+ GBM cells.
CONCLUSIONS: Together, our findings shed light on a novel role for PrPC as a potential modulator of vesicle biology in GBM, which is pivotal for intercellular communication and cancer maintenance. We also introduce GBMdiscovery, a novel user-friendly tool that allows the investigation of specific genes in GBM biology.