Tgf-Beta Signature Is A Therapeutic Biomarker For Combination Immunotherapy For Hepatocellular Carcinoma

Background: Several immune checkpoint inhibitors have recently shown promising results in patients with advanced hepatocellular carcinoma (HCC). However, tumor response rates ranged from 14% to 17%. Thus, there remains a large unmet medical need for novel and effective immunotherapeutic strategies against HCC. Dysregulated signaling in the transforming growth factor (TGF)-β pathway plays a central role in immunomodulation, inflammation, and fibrogenesis in the HCC microenvironment. We therefore used The Cancer Genome Atlas database to analyze potential therapeutic approaches combining TGF-β inhibition and immunotherapies for HCC. Methods: Transcriptomic analyses were performed in 193 HCC cases. Pathway analyses were performed by correlating 70 published signatures with TGF-β signatures. Results: 1. Unsupervised hierarchical clustering of TGF-β genes in HCC revealed four distinct clusters with unique TGF-β signatures: highly activated (14.5%), activated (45.0%), normal (30.6%), and inactivated (9.9%). 2. Highly activated TGF-β signatures were significantly associated with fibrosis and activated stromal signatures. 3. TGF-β signature subtypes were significantly associated with immune cell infiltration, T cell exhaustion, and checkpoint blockade response subclasses. 4. Potentially targetable genes were associated with specific TGF-β signatures. 5. TGF-β signatures provide potential combination therapeutic options for HCC. Conclusion: We demonstrated a specific immunosuppressive role of TGF-β in mediating immunotherapy resistance in HCC, highlighting the TGF-β signature as a potential biomarker in individualized immunotherapeutic approaches in HCC. Citation Format: Jian Chen, Xiaoping Su. TGF-β signature is a therapeutic biomarker for combination immunotherapy for hepatocellular carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4286.