Engrailed-1 and Epigenetic Vulnerabilities in Metastatic Pancreatic Cancer

Abstract public domain (NIH RePORTER)

Abstract Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal cancers, largely due to its aggressive nature and resistance to therapies. Our research focuses on the transcription factor EN1, a key regulator of the epigenome in PDA. During the R37 grant period, we made significant progress in understanding EN1's role in pancreatic cancer, including the establishment of PDA patient-derived organoids (PDOs), characterization of En1-deficient pancreatic cancer mouse models, and detailed investigation of the pancreatic epigenome upon EN1 perturbations. In the proposed 2-year extension period, we aim to expand our investigation into EN1's role in PDA through two new sub-aims. Aim 1D will explore the role of EN1 in topologically associating domains (TADs) during PDA progression. We hypothesize that EN1 modulates promoter-enhancer (PE) loop formations, impacting chromatin architecture and gene expression. To test this, we will profile tumor- and metastasis-derived organoids using Hi-C sequencing and perform genetic perturbation experiments to assess the effects of EN1 on TAD structures. This study will provide insights into how EN1-mediated changes in chromatin organization contribute to PDA progression and metastasis. Aim 2D seeks to identify and understand the roles of EN1- interacting partners in gene regulation. Preliminary IP-MS data have identified several negative regulators of transcription as EN1-interacting partners, including EZH2. We will validate these interactions through co- immunoprecipitation and investigate their functional roles using genetic and pharmacological perturbations. The proposed research aims to deepen our understanding of EN1's role in PDA by investigating its impact on TAD structures and its interactions with other transcriptional regulators. The outcomes of this study have the potential to uncover novel mechanisms driving PDA progression and identify new targets for therapeutic intervention, ultimately contributing to the development of more effective treatments for this aggressive cancer.

Public health relevance public domain (NIH RePORTER)

Project Narrative Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal cancers, largely due to its aggressive nature and resistance to therapies. Our research focuses on the transcription factor EN1, a key regulator of the epigenome in PDA. During the R37 grant period, we made significant progress in understanding EN1's role in pancreatic cancer, including the establishment of PDA patient-derived organoids (PDOs), characterization of En1-deficient pancreatic cancer mouse models, and detailed investigation of the pancreatic epigenome upon EN1 perturbations. In the proposed 2-year extension period, we aim to expand our investigation into EN1's role in PDA through two new sub-aims. Aim 1D will explore the role of EN1 in topologically associating domains (TADs) during PDA progression. We hypothesize that EN1 modulates promoter-enhancer (PE) loop formations, impacting chromatin architecture and gene expression. To test this, we will profile tumor- and metastasis-derived organoids using Hi-C sequencing and perform genetic perturbation experiments to assess the effects of EN1 on TAD structures. This study will provide insights into how EN1-mediated changes in chromatin organization contribute to PDA progression and metastasis. Aim 2D seeks to identify and understand the roles of EN1- interacting partners in gene regulation. Preliminary IP-MS data have identified several negative regulators of transcription as EN1-interacting partners, including EZH2. We will validate these interactions through co- immunoprecipitation and investigate their functional roles using genetic and pharmacological perturbations. The proposed research aims to deepen our understanding of EN1's role in PDA by investigating its impact on TAD structures and its interactions with other transcriptional regulators. The outcomes of this study have the potential to uncover novel mechanisms driving PDA progression and identify new targets for therapeutic intervention, ultimately contributing to the development of more effective treatments for this aggressive cancer.