Abstract 3820: Spatial transcriptomics of advanced hepatocellular carcinomas distinguishes intercellular interactions in responders and non-responders to cabozantinib and nivolumab neoadjuvant therapy
Authors: Kagohara Luciane T. , Zhang Shuming , Yuan Long , Zhu Qingfeng , Anders Robert , Shu Daniel , Popel Aleksander S. , Jaffee Elizabeth M. , Yarchoan Mark , Fertig Elana J. 
Published: June 2022

Abstract
The recent development of genome-wide spatial transcriptomics (ST) approaches enable near single-cell gene expression profiling to infer cellular composition and intercellular interactions that drive cancer development and responses to therapy. This study applied ST on 10 surgical biospecimens from a clinical trial with neoadjuvant therapy with cabozantinib (multi-kinase inhibitor) and nivolumab (anti-PD-1 monoclonal antibody) with advanced hepatocellular carcinoma (HCC). Within our cohort, 6 of the samples were obtained from non-responders and 4 with demonstrated pathological response were previously associated with immune infiltration using spatial proteomics technologies. Our analysis with ST was performed to determine the specific pathways that drive immune infiltration in responders and to map intercellular interactions relevant for response and resistance to the combined therapy.Analysis of these data uncovered three main differences between responders and non-responders. First, to better understand the tumor mechanisms of response and resistance, we performed differential expression and pathway analysis only in the subset of tumor clusters from responders versus non-responders. In responders, we observed enrichment for pathways associated with immune response (TNF-alpha, IFN-gamma, T cell differentiation), while in non-responders the deregulated pathways are associated with cell growth, transcriptional activity and hypoxia (Myc, E2F, oxidative phosphorylation). Second, the intercellular interaction analyses indicate that CD8-HLA interactions are more abundant in responders, while interactions activating VEGFR, the main target of cabozantinib, are enriched in non-responders. The interaction profiles are evidence that in responders the tumor cells express tumor specific antigens that are recognized by the cytotoxic cells which activity is enhanced by nivolumab. In non-responders, the activation of the VEGF pathway is an indication that the tumor cells have developed mechanism of resistance to cabozantinib. Third, responding tumors have higher densities of immune and stromal cells, and the immune cells are enriched with aggregates composed of both B and T cells. The regions surrounded by these immune aggregates are transcriptionally distinct from regions enriched for stromal cells, suggesting that tumor gene expression profile drives immune infiltration.Overall, the ST analysis of neoadjuvant HCC treated samples detects tumor induced immune cell immune infiltration in responders compared to non-responders with enrichment of cytotoxic interactions to eliminate the tumor cells. It also identifies intercellular interactions suggestive of resistance to anti-VEGF blockade.
Citation Format: Luciane T. Kagohara, Shuming Zhang, Long Yuan, Qingfeng Zhu, Robert Anders, Daniel Shu, Aleksander S. Popel, Elizabeth M. Jaffee, Mark Yarchoan, Elana J. Fertig. Spatial transcriptomics of advanced hepatocellular carcinomas distinguishes intercellular interactions in responders and non-responders to cabozantinib and nivolumab neoadjuvant therapy [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 3820.