- Lin, Lehang;
- Huang, Moli;
- Shi, Xianping;
- Mayakonda, Anand;
- Hu, Kaishun;
- Jiang, Yan-Yi;
- Guo, Xiao;
- Chen, Li;
- Pang, Brendan;
- Doan, Ngan;
- Said, Jonathan W;
- Xie, Jianjun;
- Gery, Sigal;
- Cheng, Xu;
- Lin, Zhaoyu;
- Li, Jinsong;
- Berman, Benjamin P;
- Yin, Dong;
- Lin, De-Chen;
- Koeffler, H Phillip
As the second most common malignant bone tumor in children and adolescents, Ewing sarcoma is initiated and exacerbated by a chimeric oncoprotein, most commonly, EWS-FLI1. In this study, we apply epigenomic analysis to characterize the transcription dysregulation in this cancer, focusing on the investigation of super-enhancer and its associated transcriptional regulatory mechanisms. We demonstrate that super-enhancer-associated transcripts are significantly enriched in EWS-FLI1 target genes, contribute to the aberrant transcriptional network of the disease, and mediate the exceptional sensitivity of Ewing sarcoma to transcriptional inhibition. Through integrative analysis, we identify MEIS1 as a super-enhancer-driven oncogene, which co-operates with EWS-FLI1 in transcriptional regulation, and plays a key pro-survival role in Ewing sarcoma. Moreover, APCDD1, another super-enhancer-associated gene, acting as a downstream target of both MEIS1 and EWS-FLI1, is also characterized as a novel tumor-promoting factor in this malignancy. These data delineate super-enhancer-mediated transcriptional deregulation in Ewing sarcoma, and uncover numerous candidate oncogenes which can be exploited for further understanding of the molecular pathogenesis for this disease.