Abstract 789: Elucidating transcriptional dynamics in neuroendocrine differentiation of advanced prostate cancer

Small cell carcinomas of the lung, bladder, and prostate share similar transcription patterns and drug sensitivities. Due to their high cellular plasticity, these cancers often escape treatment through a trans-differentiation from adenocarcinoma to the neuroendocrine state. We previously developed a pan small cell cancer in vitro/in vivo model named PARCB that can recapitulate this transition from primary patient tissues. To understand which transcription factors may be important in this transition, we conducted bulk and single cell RNA sequencing over time. We identified a developmental trajectory that is shared among all samples and is defined by stage-specific transcription factors. We plan to interrogate the role that these transcription factors play in the PARCB transformation assay. We performed ATAC sequencing to investigate how these transcription factors regulate these transitional states. Our study will provide a basic understanding of the transcriptional changes that occur during neuroendocrine differentiation and provide new potential therapeutic targets for small cell cancers. Citation Format: Chia-Chun Chen, Kai Song, Wendy Tran, Matthew Obusan, Tyler Sugimoto, Katherine Sheu, Donghui Cheng, Grigor Varuzhanyan, Liang Wang, Lisa Ta, Zhiyuan Mao, Nathanael Bangayan, Jung-Wook Park, Thomas Graerber, Owen Witte. Elucidating transcriptional dynamics in neuroendocrine differentiation of advanced prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 789.