Abstract 145: Engineered hydrogel platform reveals integrin-ECM mechanisms and therapeutic targets in esophageal adenocarcinoma

Abstract INTRODUCTION: Esophageal adenocarcinoma (EAC) is an aggressive cancer with poor prognosis, partly due to its complex interaction with the extracellular matrix (ECM), which influences disease progression and therapy resistance. However, the underlying ECM-driven mechanisms of EAC growth and therapeutic resistance remain unknown. Traditional in vitro models are limited by their use of cancer cell lines and lack of 3D cellular interactions. To address this gap, we developed a bioengineered hydrogel system integrated with patient-derived 3D organoids (PDOs) to better replicate the native ECM environment in EAC. METHODS: We engineered a hyaluronic acid (HA)-based hydrogel with tunable physicochemical properties to support the culture of EAC PDOs. To study ECM component-specific influences on EAC mechanobiology, we tethered individual adhesive peptides corresponding to key ECM components onto the hydrogel backbone: RGD (fibronectin), GFOGER (collagen), and YIGSR, AG73, or IKVAV (laminin). By independently varying the type and density of each peptide, we examined their effects on PDO growth, proliferation, and therapeutic resistance. Additionally, we conducted inhibition studies using integrin-targeting small molecule inhibitors to explore the role of integrin-mediated adhesion in sensitizing PDOs to chemotherapy. RESULTS: Among the five adhesive peptides tested, RGD had the most significant effect on PDO formation, growth, and proliferation. Transcriptional and protein analyses revealed elevated expression of integrin αv, integrin β1, and Yap in PDOs cultured in NorHA-RGD hydrogels compared to other peptides. These findings were validated in EAC patient tissue samples. Additional experiments demonstrated a concentration-dependent effect of RGD on PDO growth and Yap activation, mirroring the increased fibronectin deposition observed in EAC tissue. Treatment with cilengitide, an ανβ3 integrin inhibitor, in RGD-modified hydrogels significantly reduced PDO formation, and enhanced the sensitivity of PDOs to standard chemotherapy. CONCLUSION: This study establishes an engineered biomaterial platform that recapitulates key ECM biochemical properties, providing a foundation for pre-clinical drug testing and mechanistic studies. Our data indicate that αvβ3 integrin-mediated adhesion is critical for EAC PDO growth and activation of oncogenic pathways. The efficacy of cilengitide within this model suggests that targeting fibronectin-integrin αvβ3 interactions could be a viable therapeutic strategy for EAC when combined with chemotherapy. Ongoing work will extend this platform to in vivo models to investigate chemoresistance mechanisms and characterize αvβ3+ cancer stem cell populations. Citation Format: Daniel E. Garcia, Esha A. Uddin, Noriyuki Nishiwaki, Yasuto Tomita, Joel T. Gabre, Hiroshi Nakagawa, Ricardo Cruz-Acuña. Engineered hydrogel platform reveals integrin-ECM mechanisms and therapeutic targets in esophageal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 145.