Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer. Sorafenib, regorafenib, lenvatinib and cabozantinib are tyrosine kinase inhibitors (TKIs) that target, in part, vascular endothelial growth factor receptors, and are approved in various regions of the world for the treatment of advanced HCC. All these agents are associated with a range of adverse events (AEs) that can have a substantial impact on patients' health-related quality of life. Fatigue, diarrhoea, hand-foot skin reaction, nausea, vomiting, decreased appetite, hypertension and weight loss are among the most common AEs experienced with these four TKIs. In this review, we discuss strategies for the management of these AEs in patients with advanced HCC, with the aim of maximizing treatment benefits and minimizing the need for TKI treatment discontinuation. We also consider potential TKI-drug interactions and discuss the use of TKIs in patients with liver dysfunction or who have experienced tumour recurrence after liver transplantation. Use of appropriate AE management strategies and avoidance of contraindicated drugs should help patients with advanced HCC to achieve optimal outcomes with TKIs.

Myeloid-derived suppressor cells (MDSC) include immature monocytic (M-MDSC) and granulocytic (PMN-MDSC) cells that share the ability to suppress adaptive immunity and to hinder the effectiveness of anticancer treatments. Of note, in response to IFNγ, M-MDSCs release the tumor-promoting and immunosuppressive molecule nitric oxide (NO), whereas macrophages largely express antitumor properties. Investigating these opposing activities, we found that tumor-derived prostaglandin E2 (PGE2) induces nuclear accumulation of p50 NF-κB in M-MDSCs, diverting their response to IFNγ toward NO-mediated immunosuppression and reducing TNFα expression. At the genome level, p50 NF-κB promoted binding of STAT1 to regulatory regions of selected IFNγ-dependent genes, including inducible nitric oxide synthase (Nos2). In agreement, ablation of p50 as well as pharmacologic inhibition of either the PGE2 receptor EP2 or NO production reprogrammed M-MDSCs toward a NOS2low/TNFαhigh phenotype, restoring the in vivo antitumor activity of IFNγ. Our results indicate that inhibition of the PGE2/p50/NO axis prevents MDSC-suppressive functions and restores the efficacy of anticancer immunotherapy. Significance: Tumor-derived PGE2-mediated induction of nuclear p50 NF-κB epigenetically reprograms the response of monocytic cells to IFNγ toward an immunosuppressive phenotype, thus retrieving the anticancer properties of IFNγ.

Systemic inflammation is a hallmark of cancer, and it has a pivotal role in hepatocellular carcinoma (HCC) development and progression. We conducted a retrospective study including 362 patients receiving immune check-point inhibitors (ICIs) across three continents, evaluating the influence of neutrophiles to lymphocytes ratio (NLR), platelets to lymphocytes ratio (PLR), and prognostic nutritional index (PNI) on overall (OS), progression free survival (PFS), and radiologic responses. In our 362 patients treated with immunotherapy, median OS and PFS were 9 and 3.5 months, respectively. Amongst tested inflammatory biomarkers, patients with NLR ≥ 5 had shorter OS (7.7 vs. 17.6 months, p < 0.0001), PFS (2.1 vs. 3.8 months, p = 0.025), and lower objective response rate (ORR) (12% vs. 22%, p = 0.034); similarly, patients with PLR ≥ 300 reported shorter OS (6.4 vs. 16.5 months, p < 0.0001) and PFS (1.8 vs. 3.7 months, p = 0.0006). NLR emerged as independent prognostic factors for OS in univariate and multivariate analysis (HR 1.95, 95%CI 1.45–2.64, p < 0.001; HR 1.73, 95%CI 1.23–2.42, p = 0.002) and PLR remained an independent prognostic factor for both OS and PFS in multivariate analysis (HR 1.60, 95%CI 1.6–2.40, p = 0.020; HR 1.99, 95%CI 1.11–3.49, p = 0.021). Systemic inflammation measured by NLR and PLR is an independent negative prognostic factor in HCC patients undergoing ICI therapy. Further studies are required to understand the biological mechanisms underlying this association and to investigate the predictive significance of circulating inflammatory biomarkers in HCC patients treated with ICIs.

Systemic inflammation is a key risk factor for hepatocellular carcinoma (HCC) progression and poor outcomes. Inflammatory markers such as the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) may have prognostic value in HCC treated with standard of care atezolizumab plus bevacizumab (Atezo-Bev). We conducted a multicenter, international retrospective cohort study of patients with unresectable HCC treated with Atezo-Bev to assess the association of NLR and PLR with overall survival (OS), progression-free survival (PFS), and objective response rates. Patients with NLR ≥ 5 had a significantly shorter OS (9.38 vs. 16.79 months, p < 0.001) and PFS (4.90 vs. 7.58 months, p = 0.03) compared to patients with NLR < 5. NLR ≥ 5 was an independent prognosticator of worse OS (HR 2.01, 95% CI 1.22–3.56, p = 0.007) but not PFS. PLR ≥ 300 was also significantly associated with decreased OS (9.38 vs. 15.72 months, p = 0.007) and PFS (3.45 vs. 7.11 months, p = 0.04) compared to PLR < 300, but it was not an independent prognosticator of OS or PFS. NLR and PLR were not associated with objective response or disease control rates. NLR ≥ 5 independently prognosticated worse survival outcomes and is worthy of further study and validation.

Cancer induces alteration of hematopoiesis to fuel disease progression. We report that in tumor-bearing mice the macrophage colony-stimulating factor elevates the myeloid cell levels of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD salvage pathway, which acts as negative regulator of the CXCR4 retention axis of hematopoietic cells in the bone marrow. NAMPT inhibits CXCR4 through a NAD/Sirtuin 1–mediated inactivation of HIF1α-driven CXCR4 gene transcription, leading to mobilization of immature myeloid-derived suppressor cells (MDSC) and enhancing their production of suppressive nitric oxide. Pharmacologic inhibition or myeloid-specific ablation of NAMPT prevented MDSC mobilization, reactivated specific antitumor immunity, and enhanced the antitumor activity of immune checkpoint inhibitors. Our findings identify NAMPT as a metabolic gate of MDSC precursor function, providing new opportunities to reverse tumor immunosuppression and to restore clinical efficacy of immunotherapy in patients with cancer. Significance: These findings identify NAMPT as a metabolic gate of MDSC precursor function, providing new opportunities to reverse tumor immunosuppression and to restore clinical efficacy of immunotherapy in cancer patients.

Immune checkpoint inhibitors (ICI) have shown positive results in patients with hepatocellular carcinoma (HCC). As liver function contributes to prognosis, its precise assessment is necessary for the safe prescribing and clinical development of ICI in HCC. We tested the accuracy of the albumin-bilirubin (ALBI) grade as an alternative prognostic biomarker to the Child-Turcotte-Pugh (CTP). In a prospectively maintained multi-centre dataset of HCC patients, we assessed safety and efficacy of ICI across varying levels of liver dysfunction described by CTP (A to C) and ALBI grade and evaluated uni- and multi-variable predictors of overall (OS) and post-immunotherapy survival (PIOS). We studied 341 patients treated with programmed-death pathway inhibitors (n = 290, 85%). Pre-treatment ALBI independently predicted for OS, with median OS of 22.5, 9.6, and 4.6 months across grades (p < 0.001). ALBI was superior to CTP in predicting 90-days mortality with area under the curve values of 0.65 (95% CI 0.57–0.74) versus 0.63 (95% CI 0.54–0.72). ALBI grade at ICI cessation independently predicted for PIOS (p < 0.001). Following adjustment for ICI regimen, neither ALBI nor CTP predicted for overall response rates or treatment-emerging adverse events (p > 0.05). ALBI grade identifies a subset of patients with prolonged survival prior to and after ICI therapy, lending itself as an optimal stratifying biomarker to optimise sequencing of systemic therapies in advanced HCC.