Anlotinib potentiates anti‐PD1 immunotherapy via transferrin receptor‐dependent CD8+ T‐cell infiltration in hepatocellular carcinoma

Abstract

Abstract Background The therapeutic potential of immune checkpoint blockade (ICB) extends across various cancers; however, its effectiveness in treating hepatocellular carcinoma (HCC) is frequently curtailed by both inherent and developed resistance. Objective This research explored the effectiveness of integrating anlotinib (a broad‐spectrum tyrosine kinase inhibitor) with programmed death‐1 (PD‐1) blockade and offers mechanistic insights into more effective strategies for treating HCC. Methods Using patient‐derived organotypic tissue spheroids and orthotopic HCC mouse models, we assessed the effectiveness of anlotinib combined with PD‐1 blockade. The impact on the tumour immune microenvironment and underlying mechanisms were assessed using time‐of‐flight mass cytometry, RNA sequencing, and proteomics across cell lines, mouse models, and HCC patient samples. Results The combination of anlotinib with an anti‐PD‐1 antibody enhanced the immune response against HCC in preclinical models. Anlotinib remarkably suppressed the expression of transferrin receptor (TFRC) via the VEGFR2/AKT/HIF‐1α signaling axis. CD8+ T‐cell infiltration into the tumour microenvironment correlated with low expression of TFRC. Anlotinib additionally increased the levels of the chemokine CXCL14, crucial for attracting CD8+ T cells. CXCL14 emerged as a downstream effector of TFRC, exhibiting elevated expression following the silencing of TFRC. Importantly, low TFRC expression was also associated with a better prognosis, enhanced sensitivity to combination therapy, and a favourable response to anti‐PD‐1 therapy in patients with HCC. Conclusions Our findings highlight anlotinib's potential to augment the efficacy of anti‐PD‐1 immunotherapy in HCC by targeting TFRC and enhancing CXCL14‐mediated CD8+ T‐cell infiltration. This study contributes to developing novel therapeutic strategies for HCC, emphasizing the role of precision medicine in oncology. Highlights Synergistic effects of anlotinib and anti‐PD‐1 immunotherapy demonstrated in HCC preclinical models. Anlotinib inhibits TFRC expression via the VEGFR2/AKT/HIF‐1α pathway. CXCL14 upregulation via TFRC suppression boosts CD8+ T‐cell recruitment. TFRC emerges as a potential biomarker for evaluating prognosis and predicting response to anti‐PD‐1‐based therapies in advanced HCC patients.

Keywords

• hepatocellular carcinoma
• immune checkpoint blockade
• transferrin receptor
• tumour microenvironment
• tyrosine kinase inhibitor