Abstract A054: Stromal dynamics in PDAC: The role of NetrinG proteins in regulating fibroblast function

Abstract Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers, with a five-year survival rate of just 13%; a consequence of late diagnosis and limited therapeutic options. Surgical resection is the only potential cure, yet most patients are ineligible, and recurrence is frequent even after surgery. These challenges underscore the urgent need for advanced strategies. Given PDAC’s unique biology, integrating tumor microenvironment (TME) reprogramming with robust, status-informing theranostic markers represents a promising direction for future research. This is because a defining feature of PDAC is its dense, fibrotic stroma, driven by functional units of cancer-associated fibroblasts (CAFs) and their extracellular matrix (ECM). Unlike normal, tumor-suppressive fibroblast/ECM units, CAF/ECM functional units adopt an activated phenotype, often mediated by pathways such as TGF-β that alters integrin-dependent cell-ECM interactions, promotes tumor progression, and shapes drug responses through dynamic tumor-stroma signaling reciprocity. However, indiscriminate stromal ablation can paradoxically accelerate tumor growth, highlighting the need to precisely distinguish and modulate tumor-promoting versus tumor-suppressive CAF/ECM states. Recent evidence suggests that Netrin G1 (NetG1) -positive CAFs enhance glutamate and glutamine exchange with cancer and immune cells via the NetG1–NGL1 axis, mimicking synaptic communication and fostering both tumor growth and immunosuppression. Inhibition of this pathway has been shown to suppress PDAC progression in experimental models and the expression of these molecules in TME and cancer cells correlates with poor patient outcomes. Notably, although the clinical utility of NetrinG family members remains to be fully elucidated, recent analyses of publicly available transcriptional data reveal that high NetG2 expression, unlike published data for NetG1, correlates with improved survival. These findings suggest that additional NetrinG proteins could serve as modulators and status-informing markers of the TME, with the added potential to become new druggable TME function upholding targets. Here, we investigate the diverse, context-dependent roles of NetrinG proteins, including NGL1, NetG1, NGL2, NetG2, NGL3, and LAR, in modulating fibroblast states and the PDAC TME. Using optimized 3D fibroblast/ECM unit models and advanced imaging workflows that include Python-based analysis, FIJI, and AI-powered tools like StarDist, we dissect ECM architecture, nuclear features, and more. Our findings establish a research platform for unraveling the mechanistic and therapeutic potential of NetrinG proteins in PDAC and provide a basis for future studies aimed at validating their roles as potential theranostic targets. Citation Format: Aleksandr Dolskii, Olivia C. Williams, Tiffany Luong, Jaye Gardiner, Janusz Franco-Barraza, Mariia Dmitrieva, Sérgio A. Alcantara Dos Santos, Edna Cukierman. Stromal dynamics in PDAC: The role of NetrinG proteins in regulating fibroblast function abstract. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research—Emerging Science Driving Transformative Solutions; Boston, MA; 2025 Sep 28-Oct 1; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2025;85 (18Suppl₃): Abstract nr A054.