An Integrative Approach to Identify Vulnerabilities in Pediatric Cancer DSRCT

项目摘要 促结缔组织增生性小圆细胞瘤（DSRCT）是一种复发性染色体易位， 创建了一个嵌合转录因子，EWS-WT 1，这是唯一已知的致癌驱动DSRCT。 不幸的是，致癌转录因子如EWS-WT 1难以靶向治疗。给定 标准治疗对DSRCT不是很有效（5年生存率低于15%）， 迫切需要基于理性的靶向治疗。为此，新的脆弱致癌靶点 EWS-WT 1的下游必须被识别。不幸的是，人们对这种可能性知之甚少， DSRCT中的脆弱目标为了识别DSRCT中的漏洞，我们进行了整合基因 使用EWS-WT 1耗尽的DSRCT细胞和28个原代DSRCT的表达谱的表达分析 样品该分析鉴定了可能对DSRCT细胞生长和存活至关重要的几种激酶。 大多数癌症都含有一小群肿瘤起始细胞（TIC），这些细胞被认为是种子细胞。 但在DSRCT中尚未发现TIC。我们最近发现了一个 在DSRCT中产生球状体的新培养条件，其显示显著更高的肿瘤接种 比贴壁细胞的活性。球状体的深度RNA测序分析揭示了一些 富含球状体的激酶。因此，本提案的目标是确定 DSRCT最终将导致基于理性的靶向治疗的发展。 目标1.调查确定的激酶作为DSRCT中的潜在漏洞。我们已经确认NTRK 3 在原发性DSRCT肿瘤和DSRCT细胞中高度表达的ROCK 2和SIK 1激酶。我们将 研究抑制这些激酶对体外和体内DSRCT细胞生长的影响。 目标二。研究BLK、NTRK 3和ROCK 2在球状体中的作用。我们的深度RNA测序分析 高致瘤性球状体的研究揭示了一些激酶，其表达在高致瘤性球状体中大大增加。 球状体我们将研究抑制这些激酶对球体致瘤能力的影响 使用我们的原位腹膜内DSRCT异种移植模型。 DSRCT仍然无法治疗，死亡率高得不可接受。我们的整合基因表达分析 我们最近在DSRCT中发现的球状体揭示了几种激酶， DSRCT生长或存活。这些相辅相成的办法将最终导致 DSRCT中的持久靶向治疗。我们在识别易受攻击目标方面的综合方法可以 应用于发现其他相关儿科肉瘤如尤文肉瘤的关键依赖性。

Project Summary Desmoplastic Small Round Cell Tumor (DSRCT) is defined by a recurrent chromosomal translocation that creates a chimeric transcription factor, EWS-WT1, which is the only known oncogenic driver of DSRCT. Unfortunately, oncogenic transcription factors such as EWS-WT1 are difficult to target for therapy. Given that standard treatments are not very effective for DSRCT (less than15% 5 year survival), development of rationale-based targeted therapy is urgently needed. To do so, new vulnerable oncogenic targets downstream of EWS-WT1 must be identified. Unfortunately, not much is known about the potential vulnerable targets in DSRCT. To identify the vulnerabilities in DSRCT, we performed integrative gene expression analysis using expression profiles of EWS-WT1-depleted DSRCT cells and 28 primary DSRCT samples. This analysis identified several kinases that could be critical for DSRCT cell growth and survival. Most cancers contain a small population of tumor initiating cells (TICs) that are thought to serve as seeds for recurrent tumor growth, but TICs have not yet been identified in DSRCT. We have recently identified a novel culture condition that produces spheroids in DSRCT which display significantly higher tumor-seeding activity than the adherent cells. Deep RNA sequencing analysis of spheroids has revealed a number of kinases that are enriched in spheroids. Thus, the goal of this proposal is to identify key vulnerabilities in DSRCT that will ultimately lead to development of rationale-based targeted therapy. Aim 1. Investigate the identified kinases as potential vulnerabilities in DSRCT. We have identified NTRK3, ROCK2 and SIK1 kinases that are highly expressed in primary DSRCT tumors and in DSRCT cells. We will investigate the effects of inhibiting these kinases on DSRCT cell growth in vitro and in vivo. Aim 2. Investigate the roles of BLK, NTRK3 and ROCK2 in spheroids. Our deep RNA sequencing analysis of highly tumorigenic spheroids has revealed a number of kinases whose expression is greatly increased in spheroids. We will investigate the effects of inhibiting these kinases in tumorigenic capacity of spheroids using our orthotopic intraperitoneal DSRCT xenograft model. DSRCT remains untreatable with unacceptably high mortality. Our integrative gene expression analysis and our recent discovery of spheroids in DSRCT have revealed several kinases that could be critical for DSRCT growth or survival. These complementary approaches will ultimately lead to development of durable targeted therapies in DSRCT. Our integrative approach in identifying vulnerable targets could be applied to finding critical dependencies in other related pediatric sarcomas such as Ewing sarcoma.