Abstract 633: Delineating tumor-neural communication in brain metastasis with spatiotemporal transcriptomic analysis and multi-cellular crosstalk modeling

Abstract

Abstract Brain metastases are diagnosed in 20-40% of all cancer patients. Despite the advancements in neurosurgery, radiotherapy, and chemotherapy, one-year survival of metastatic brain tumor patients still within a single digit such that brain metastases constitute about 20% of annual cancer deaths. These facts clearly indicate a critical need for better understanding of mechanisms that promote the growth of brain metastases. Emerging data, including ours, indicate that different types of metastatic cancer cells leverage dissimilar sets of neurotransmitters to favor their outgrowth in the brain. However, there are over sixty types of neurotransmitters in the brain being synthesized and released by various types of neural cells, we need a systemic investigation of how they mediate the pathogenesis of brain metastases in concert. Since neurotransmitters, gliotransmitters, neurotrophic factors, and neural cytokines, called neuroactive substances, are the most abundant and key intercellular communication signals in the brain, we hypothesize that tumor cells leverage these neuroactive substances to assimilate into neural circuitry via communicating with neural cells including neurons, astrocytes, microglia, oligodendrocyte, and others, in promoting the vicious circle of tumor-neural crosstalk during brain metastasis development. By performing spatial transcriptomics analysis on mouse brain sections bearing metastatic tumors, we found that tumor lesions at different locations and even tumor-surrounding areas in the brain regions could be differentiated into different cellular clusters based on gene transcriptomic expressions. We further predicted several paracrine and autocrine signaling between and within tumors as well as tumor-surrounding neural niches in different tumor locations (e.g., centers or edges), of different tumor sizes, and at various tumor development stages, using our Cell-Cell Communication Explorer (CCC-Explorer) modeling software. Functional experiments were conducted to demonstrate that cell type-specific depletion of the secreted NSs deactivated the activities of corresponding receptors and downstream signaling in co-cultured metastatic brain tumor cells. Characterizing spatiotemporal tumor-neural crosstalk in the brain metastatic niche would provide a new strategy in the development of novel and effective therapeutics of brain metastases. Citation Format: Xin Wang, Ying Zhu, Jianting Sheng, Hong Zhao, Stephen Wong. Delineating tumor-neural communication in brain metastasis with spatiotemporal transcriptomic analysis and multi-cellular crosstalk modeling [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 633.