Abstract 2590: Characterization of tumor-neuron communication in lung adenocarcinoma brain metastasis

Abstract 30-40% of cancer patients with lung cancer develop brain metastasis with poor prognosis. The incidence of brain metastasis has increased in patients that have received standard of care treatment, including targeted therapies. The mechanisms which promote lung cancer cell dissemination and colonization of the central nervous system (CNS) remain understudied and identifying novel drug targets to treat brain metastasis is an unmet clinical need. By using a variety of animal models of lung cancer metastasis, we previously identified shifts in epithelial and neuronal like lineage gene expression programs in malignant cells as they adapt to the brain tumor microenvironment (TME) in vivo. Gene set enrichment analysis (GSEA) revealed that most of genes are involved in neuronal guidance and cell adhesion pathways (L2FC > 0.5, padj < 0.05, Log2RPKM > 1 compared to 2D culture). We also examined tumor-neuron interactions in patient derived surgical biopsies and found active areas of interaction between tumors and neurons in human lung adenocarcinoma (LUAD) brain metastasis. Spatial transcriptomics of human brain metastasis also revealed differential profiles for areas of active interaction. In vitro, we established co-culture conditions which demonstrate that primary neurons can directly interact with brain metastatic LUAD cells and improve their fitness. Based on these observations, we performed a custom Clustered regularly interspaced palindromic repeats (CRISPR)-Cas9 loss of function screen targeting 470 neuronal and cell adhesion genes that are up-regulated in LUAD cells that seed the brain in vivo. Moreover, we performed our screens under different conditions which recapitulate tumor cell-tumor cell clustering in 3-dimensional culture conditions (3D) or tumor-neuron co-clustering in 3D. Results from this differential screening approach suggests that LUAD cells are increasingly, but not exclusively, dependent on several neuronal genes as they are co-cultured with neurons. In conclusion, we have modelled direct tumor-neuronal cell interaction in vitro, shown that it is an important component of brain metastasis, and identified putative targets that can be inhibited to disrupt tumor-neuron interactions and potentially limit brain metastatic progression. Citation Format: Sampada Chande, Don Nguyen, Atsushi Yamasaki, Veronica Chiang, Declan McGuone. Characterization of tumor-neuron communication in lung adenocarcinoma brain metastasis [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 2590.