The immunomodulatory activity of lenvatinib prompts the survival of patients with advanced hepatocellular carcinoma

Small-molecule-based targeted therapy in liver cancer

Liver cancer is one of the most prevalent malignant tumors worldwide. According to the Barcelona Clinic Liver Cancer staging criteria, clinical guidelines provide tutorials to clinical management of liver cancer at their individual stages. However, most patients diagnosed with liver cancer are at advanced stage; therefore, many researchers conduct investigations on targeted therapy, aiming to improve the overall survival of these patients. To date, small-molecule-based targeted therapies are highly recommended (first line: sorafenib and lenvatinib; second line: regorafenib and cabozantinib) by current the clinical guidelines of the American Society of Clinical Oncology, European Society for Medical Oncology, and National Comprehensive Cancer Network. Herein, we summarize the small-molecule-based targeted therapies in liver cancer, including the approved and preclinical therapies as well as the therapies under clinical trials, and introduce their history of discovery, clinical trials, indications, and molecular mechanisms. For drug resistance, the revealed mechanisms of action and the combination therapies are also discussed. In fact, the known small-molecule-based therapies still have limited clinical benefits to liver cancer patients. Therefore, we analyze the current status and give our ideas for the urgent issues and future directions in this field, suggesting clues for novel techniques in liver cancer treatment.

Tumor microenvironment-responsive manganese-based nano-modulator activate the cGAS-STING pathway to enhance innate immune system response

BACKGROUND

Manganese ions (Mn2+) combined with adjuvants capable of damaging and lysing tumor cells form an antitumor nano-modulator that enhances the immune efficacy of cancer therapy through the cascade activation of the cyclic GMP-AMP interferon gene synthase-stimulator (cGAS-STING) pathway, which underscores the importance of developing antitumor nano-modulators, which induce DNA damage and augment cGAS-STING activity, as a critical future research direction. METHODS AND RESULTS: We have successfully synthesized an antitumor nano-modulator, which exhibits good dispersibility and biosafety. This nano-modulator is engineered by loading manganese dioxide nanosheets (M-NS) with zebularine (Zeb), known for its immunogenicity-enhancing effects, and conducting targeted surface modification using hyaluronic acid (HA). After systemic circulation to the tumor site, Mn2+, Zeb, and reactive oxygen species (ROS) are catalytically released in the tumor microenvironment by H+ and H2O2. These components can directly or indirectly damage the DNA or mitochondria of tumor cells, thereby inducing programmed cell death. Furthermore, they promote the accumulation of double-stranded DNA (dsDNA) in the cytoplasm, enhancing the activation of the cGAS-STING signalling pathway and boosting the production of type I interferon and the secretion of pro-inflammatory cytokines. Additionally, Zeb@MH-NS enhances the maturation of dendritic cells, the infiltration of cytotoxic T lymphocytes, and the recruitment of natural killer cells at the tumor site.

CONCLUSIONS

This HA-modified manganese-based hybrid nano-regulator can enhance antitumor therapy by boosting innate immune activity and may provide new directions for immunotherapy and clinical translation in cancer.

Dynamics of the neutrophil‑to‑lymphocyte ratio during lenvatinib treatment for unresectable hepatocellular carcinoma

Lenvatinib is an approved therapy for advanced hepatocellular carcinoma (HCC). Recently, immune checkpoint inhibitors have been approved as frontline chemotherapies for HCC, and the tumor immune microenvironment (TIME) has been demonstrated to significantly affect HCC treatment. The neutrophil-to-lymphocyte ratio (NLR) is associated with the TIME, and the dynamics of the NLR are associated with prognosis or treatment efficacy in various cancer types. The present study investigated the dynamics of the TIME using the NLR in 101 patients with HCC treated with lenvatinib. Immunostaining for CD8+ tumor-infiltrating lymphocytes (TILs) was also performed in 9 patients who underwent liver tumor biopsy prior to subsequent chemotherapy for progression or discontinuation due to adverse events on lenvatinib treatment. The NLR values measured at the start of treatment (SOT), after 1 month of treatment and after 3 months of treatment were 2.78±2.20, 2.61±1.86 and 2.66±2.36, respectively (P=0.733). Among the patients with no reduction in the initial dose, there was no significant difference between the NLR after 1 month (2.34±0.25) and that at the SOT (2.86±2.33) (P=0.613). In patients who achieved a complete or partial response, the NLR at the time of the best tumor response was 1.65±0.56, which was significantly lower than that at the SOT (2.05±0.78) (P=0.023). In patients who did not respond to lenvatinib, the NLR at the time of disease progression was 3.68±3.19, which was significantly higher than that at the SOT (2.78±1.79) (P=0.043). Overall, 5 out of the 6 patients who did not respond to lenvatinib had low CD8+ TIL counts at disease progression. Although the present study included a limited number of patients, the NLR was associated with the therapeutic effects of lenvatinib. These findings suggest the potential of lenvatinib as an immunomodulator.

Clinicopathological features of kidney injury in patients receiving immune checkpoint inhibitors (ICPi) combined with anti-vascular endothelial growth factor (anti-VEGF) therapy

BACKGROUND

Immune checkpoint inhibitor (ICPi) combined with anti-vascular endothelial growth factor (VEGF) therapy has increasingly become a promising strategy in various malignancies. However, the combination might be associated with increased risk of nephrotoxicity.

METHODS

We retrospectively recruited patients who suffered kidney injury and received renal biopsy after anti-VEGF/ICPi mono- or combination therapy and divided them into three groups: anti-VEGF monotherapy, ICPi monotherapy and combination therapy. Clinical and histopathological features of three groups were analysed. All patients were followed-up for 3 months after biopsy, with or without glucocorticoid treatment, and renal outcome were compared.

RESULTS

A total of 46 patients were enrolled. Eighteen patients received anti-VEGF monotherapy, 12 received ICPi monotherapy and 16 received combined treatment of anti-VEGF and ICPi. Proteinuria level of anti-VEGF group, ICPi group and combination group were 4.07±3.17 g/day, 0.60±0.61 g/day and 2.05±2.50 g/day, respectively (p=0.002). The peak serum creatinine level of combination group (1.75±0.77 mg/dL) was also in between ICPi group (2.79±0.90 mg/dL) and anti-VEGF group (1.34±0.60 mg/dL) (p<0.001). Multiple histopathological patterns involving glomerulus, tubulointerstitium and vessel existed in the majority of cases in combination group (68.8%). Renal complete and partial recovery rate of combination therapy were also in between monotherapy (57.1% vs 40.0% in anti-VEGF group, 100.0% in ICPi group, respectively).

CONCLUSIONS

Kidney injury in patients treated with combination therapy of ICPi and anti-VEGF shows hybrid pathological patterns and intermediate clinical features compared with monotherapy. Cohorts with larger sample and better design, as well as basic research, are needed to elucidate the mechanism of 'protection' effect of combination anti-cancer therapy to renal function.

Fibroblast growth factor inhibition by molecular-targeted agents mitigates immunosuppressive tissue microenvironment in hepatocellular carcinoma

BACKGROUND & AIMS

Combination immunotherapy refers to the use of immune checkpoint inhibitors (ICI) and molecular-targeted agents (MTA), which have recently been approved for the treatment of advanced hepatocellular carcinoma (HCC). Owing to its relatively low antitumor effect (up to 30%), sequential therapy following ICIs treatment is required in patients with HCC. This study aimed to determine the impact of MTAs on the tumor immune microenvironment (TIME).

METHODS

We established immune syngeneic orthotopic HCC mouse models using Hep-55.1C and Hep-53.4, and treated them with MTAs (lenvatinib, sorafenib, regorafenib, cabozantinib, and DC101 as anti-vascular endothelial growth factor receptor-2 antibodies, and AZD4547 as a fibroblast growth factor receptor (FGFR)-1/2/3/4 inhibitor) for 2 weeks. Subsequently, alterations in the TIME caused by MTAs were evaluated using immunohistochemistry (antibodies for CD3, CD8, Foxp3, Granzyme B, Arginase-1, NK1.1, F4/80, CD11c, PD-1, and PD-L1). We conducted RNA-seq analysis using lenvatinib- and AZD4547-treated tumors. To confirm the clinical relevance of these findings, we analyzed the transcriptome data of human HCC cells (MHCC-97H) treated with various concentrations of lenvatinib for 24 h using RNA-seq data from the Gene Expression Omnibus database.

RESULTS

The number of Foxp3- and F4/80-positive cells in the TIME was decreased in many MTAs. Cabozantinib increased the numbers in NK1.1-, Granzyme B, and CD11c-positive cells. Lenvatinib and AZD4547 increased the number of CD8, Granzyme B, and PD-L1-positive cells. Gene ontology enrichment analysis revealed that lipid metabolism-related genes were downregulated by lenvatinib and AZD4547. In total, 161 genes downregulated by FGFR inhibition in rodent models overlapped with those downregulated by lenvatinib in human HCC cells.

CONCLUSIONS

In this study, we showed that cabozantinib activated the innate immune system, and lenvatinib and AZD4547, which commonly inhibit FGFR signaling, altered TIME to a hot immune state by downregulating lipid metabolism-related genes. These findings support the therapeutic use of combination immunotherapies.

Prognostic Roles of Inflammatory Biomarkers in Radioiodine-Refractory Thyroid Cancer Treated with Lenvatinib

BACKGRUOUND

Inflammatory biomarkers, such as the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR), serve as valuable prognostic indicators in various cancers. This multicenter, retrospective cohort study assessed the treatment outcomes of lenvatinib in 71 patients with radioactive iodine (RAI)-refractory thyroid cancer, considering the baseline inflammatory biomarkers.

METHODS

This study retrospectively included patients from five tertiary hospitals in Korea whose complete blood counts were available before lenvatinib treatment. Progression-free survival (PFS) and overall survival (OS) were evaluated based on the median value of inflammatory biomarkers.

RESULTS

No significant differences in baseline characteristics were observed among patients grouped according to the inflammatory biomarkers, except for older patients with a higher-than-median NLR (≥2) compared to their counterparts with a lower NLR (P= 0.01). Patients with a higher-than-median NLR had significantly shorter PFS (P=0.02) and OS (P=0.017) than those with a lower NLR. In multivariate analysis, a higher-than-median NLR was significantly associated with poor OS (hazard ratio, 3.0; 95% confidence interval, 1.24 to 7.29; P=0.015). However, neither the LMR nor the PLR was associated with PFS. A higher-than-median LMR (≥3.9) was significantly associated with prolonged OS compared to a lower LMR (P=0.036). In contrast, a higher-than-median PLR (≥142.1) was associated with shorter OS compared to a lower PLR (P=0.039).

CONCLUSION

Baseline inflammatory biomarkers can serve as predictive indicators of PFS and OS in patients with RAI-refractory thyroid cancer treated with lenvatinib.

Exploring Immunological Effects and Novel Immune Adjuvants in Immunotherapy for Salivary Gland Cancers

Salivary gland cancer (SGC) is rare and comprises over 20 histological subtypes. Recently, clinical experience regarding immunotherapies for SGCs has been accumulating, yet their efficacy remains controversial. Understanding the tumor microenvironment (TME), including the expression of immune checkpoint molecules in SGC, is crucial to optimizing immunotherapy. In this review, we demonstrate that high-grade mucoepidermoid carcinoma and salivary duct carcinoma generally exhibit immune-hot TME with high immune cell infiltration, frequent genetic mutations, and robust immune checkpoint molecule expression. In contrast, adenoid cystic carcinomas exhibit an immune-cold TME. While the reported efficacy of immune checkpoint inhibitors (ICIs) for SGCs is generally poor, several studies showed promising clinical efficacy of ICIs, with an objective response rate ranging from 20.0-33.3%, indicating that ICIs might be beneficial for a specific population of SGC. Molecule-targeted therapies including anti-human epidermal growth factor receptor 2 and anti-androgen receptor therapies have shown promising clinical efficacy against SGC. Recent evidence indicates that these molecules could be targets for antigen-specific immunotherapies including chimeric antigen receptor-T therapy and cancer vaccines. This review discusses the current understanding and future directions of immunotherapies for SGCs, including ongoing clinical trials.

Transcatheter arterial chemoembolization combined with PD-1 inhibitors and Lenvatinib for hepatocellular carcinoma with portal vein tumor thrombus

BACKGROUND

Hepatocellular carcinoma (HCC) patients complicated with portal vein tumor thrombus (PVTT) exhibit poor prognoses and treatment responses.

AIM

To investigate efficacies and safety of the combination of PD-1 inhibitor, transcatheter arterial chemoembolization (TACE) and Lenvatinib in HCC subjects comorbid with PVTT.

METHODS

From January 2019 to December 2020, HCC patients with PVTT types I-IV were retrospectively enrolled at Beijing Ditan Hospital. They were distributed to either the PTL or TACE/Lenvatinib (TL) group. The median progression-free survival (mPFS) was set as the primary endpoint, while parameters like median overall survival, objective response rate, disease control rate (DCR), and toxicity level served as secondary endpoints.

RESULTS

Forty-one eligible patients were finally recruited for this study and divided into the PTL (n = 18) and TL (n = 23) groups. For a median follow-up of 21.8 months, the DCRs were 88.9% and 60.9% in the PTL and TL groups (P = 0.046), res-pectively. Moreover, mPFS indicated significant improvement (HR = 0.25; P < 0.001) in PTL-treated patients (5.4 months) compared to TL-treated (2.7 months) patients. There were no treatment-related deaths or differences in adverse events in either group.

CONCLUSION

A triplet regimen of PTL was safe and well-tolerated as well as exhibited favorable efficacy over the TL regimen for advanced-stage HCC patients with PVTT types I-IV.

Targeting AXL induces tumor-intrinsic immunogenic response in tyrosine kinase inhibitor-resistant liver cancer

Hepatocellular carcinoma (HCC) is an aggressive malignancy without effective therapeutic approaches. Here, we evaluate the tumor-intrinsic mechanisms that attenuate the efficacy of immune checkpoint inhibitor (ICI) that is observed in patients with advanced HCC who progress on first-line tyrosine kinase inhibitor (TKI) therapy. Upregulation of AXL observed in sorafenib- and lenvatinib-resistant HCCs is correlated with poor response towards TKI and ICI treatments. AXL upregulation protects sorafenib-resistant HCC cells from oxidative stress, mitochondrial damage, and accompanying immunogenic cell death through suppressed tumor necrosis factor-α (TNF-α) and STING-type I interferon pathways. Pharmacological inhibition of AXL abrogates the protective effect and re-sensitizes TKI-resistant HCC tumors to anti-PD-1 treatment. We suggest that targeting AXL in combination with anti-PD-1 may provide an alternative treatment scheme for HCC patients who progress on TKI treatment.

Lenvatinib delivery using a Gd/Fe bimetallic MOF: Enhancing antitumor immunity following microwave-based thermal therapy

Microwave (MW) thermal therapy has been developed as an effective clinical strategy that can achieve pronounced antitumor activity and also has the potential to trigger antitumor immunity. However, patients generally face high rates of tumor recurrence following MW treatment, limiting the long-term benefits of such treatment. The combination of MW treatment and immunomodulatory strategies may represent a promising means of reprogramming the immunosuppressive tumor microenvironment (TME) in a manner conducive to lower recurrence rates. In this study, a Lenvatinib-loaded Gd/Fe metal-organic framework (Gd/FeMOF) was designed as a promising approach to enhancing such antitumor immunity. MW-enhanced dynamic Gd/FeMOF sensitization can facilitate high levels of reactive oxygen species production under MW irradiation, resulting in stronger immunogenic tumor cell death. In parallel, the Lenvatinib released from Gd/FeMOF preparations can serve as an immune adjuvant that suppresses programmed death ligand 1 (PD-L1) expression and drives the reprogramming of the immunosuppressive TME. The Gd and Fe present within this MOF preparation also imbue it with magnetic resonance imaging capabilities. Importantly, in vivo animal model experiments confirmed the ability of GdFeMOF treatment to significantly enhance antitumor immunity while protecting against recurrence. Accordingly, this study offers a foundation for promising strategies aimed at the integrated diagnosis and durable treatment of cancer. STATEMENT OF SIGNIFICANCE: High rates of tumor recurrence following MW thermal therapy limit the long-term benefits of such treatment. We found that the administration of Lenvatinib-loaded Gd/FeMOF nanoparticles significantly reduced tumor recurrence after MW thermal therapy. Under MW irradiation, the Gd/FeMOF nanoparticles were found to augment the immune response due to facilitation of the process of immunogenic cell death. In addition, the released Lenvatinib could act as an immune adjuvant to downregulate the expression of PD-L1 and reprogram the immunosuppressive state of the tumor microenvironment, thus further enhancing the immune response. This is significant because MW-induced immune responses are relatively weak and usually fail to effectively prevent tumor recurrence. The combination of MW treatment with an immunomodulatory strategy may solve this problem.

A General Biomineralization Strategy to Synthesize Autologous Cancer Vaccines with cGAS-STING Activating Capacity for Postsurgical Immunotherapy

Autologous cancer vaccines constructed by nonproliferative whole tumor cells or tumor lysates together with appropriate adjuvants represent a promising strategy to suppress postsurgical tumor recurrence. Inspired by the potency of cytosolic double-stranded DNA (dsDNA) in initiating anticancer immunity by activating the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway, we herein report the concise synthesis of a cGAS-STING agonist through dsDNA-templated biomineralization growth of calcium carbonate (CaCO₃) microparticles. The yielded DNA@CaCO₃ can activate the intracellular cGAS-STING pathway of dendritic cells (DCs) by promoting endosomal escape of dsDNA, triggering their maturation and activation as a potent immune stimulator. Upon intratumoral injection, DNA@CaCO₃ can reverse the immunosuppressive tumor microenvironment by simultaneously provoking innate and adaptive antitumor immunity, thereby effectively suppressing the growth of murine CT26 and B16-F10 tumors in mice. Furthermore, via CaCO₃-based biomineralization of complete tumor lysates, we constructed a personalized autologous cancer vaccine with intrinsic cGAS-STING activation capacity that could provoke tumor-specific immune responses to not only delay the growth of challenged tumors but also synergize with anti-PD-1 immunotherapy to suppress postsurgical tumor recurrence. This study highlights a CaCO₃-based biomineralization method to prepare autologous cancer vaccines in a concise manner, which is promising for personalized immunotherapy and clinical translation.

Higher Number of Tumor-Infiltrating PD-L1+ Cells Is Related to Better Response to Multikinase Inhibitors in Hepatocellular Carcinoma

Multikinase inhibitors (MKIs) such as sorafenib and lenvatinib are first-line treatments for unresectable hepatocellular carcinoma (HCC) and are known to have immunomodulatory effects. However, predictive biomarkers of MKI treatment in HCC patients need to be elucidated. In the present study, thirty consecutive HCC patients receiving lenvatinib (n = 22) and sorafenib (n = 8) who underwent core-needle biopsy before treatment were enrolled. The associations of CD3, CD68, and programmed cell death-ligand-1 (PD-L1) immunohistochemistry with patient outcomes, including overall survival (OS), progression-free survival (PFS), and objective response rate (ORR), were evaluated. High and low subgroups were determined according to median CD3, CD68, and PD-L1 values. Median CD3 and CD68 counts were 51.0 and 46.0 per 20,000 µm2, respectively. The median combined positivity score (CPS) of PD-L1 was 2.0. Median OS and PFS were 17.6 and 4.4 months, respectively. ORRs of the total, lenvatinib, and sorafenib groups were 33.3% (10/30), 12.5% (1/8), and 40.9% (9/22), respectively. The high CD68+ group had significantly better PFS than the low CD68+ group. The high PD-L1 group had better PFS than the low subgroup. When we analyzed the lenvatinib subgroup, PFS was also significantly better in the high CD68+ and PD-L1 groups. These findings suggest that high numbers of PD-L1-expressing cells within tumor tissue prior to MKI treatment can serve as a biomarker to predict favorable PFS in HCC patients.

Anti-CASPR2 encephalitis in a liver posttransplant patient receiving immune-suppression and lenvatinib: a case report and literature review

It has been assumed that patients with strict immunosuppressive treatment after solid organ transplantation have only marginal risk in developing autoimmune encephalitis. We reported a woman in her late 40 s who presented with generalized convulsions and loss of consciousness. After detailed history review, neuropsychological tests, metagenomic next-generation sequencing of serum and cerebrospinal fluid (CSF), magnetic resonance imaging (MRI) brain, and electroencephalogram, she was diagnosed as anti-CASPR2 encephalitis based on the positive anti-CASPR2 auto-antibody in serum and CSF. The patient underwent liver transplantation and has taken lenvatinib for 2 months, in addition to tacrolimus, mycophenotale mofetil, and entecavir administered for half a year. This case was the first report of anti-CASPR2 encephalitis in post-organ transplantation patients. Together with the reports of other encephalitis cases in organ transplantation, it warns the possibility of developing immune-oriented encephalitis in patients undergoing immunosuppression, especially in combination with other treatments of immunomodulatory activity.

Evaluating the Benefits of TACE Combined with Lenvatinib Plus PD-1 Inhibitor for Hepatocellular Carcinoma with Portal Vein Tumor Thrombus

INTRODUCTION

This study evaluated the efficacy and safety of transarterial chemoembolization (TACE) combined with lenvatinib plus programmed death (PD)-1 inhibitor (TACE-L-P) versus TACE combined with sorafenib plus PD-1 inhibitor (TACE-S-P) in the treatment of hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT).

METHODS

The clinical data of patients with HCC and PVTT treated with TACE-L-P or TACE-S-P from January 2018 to March 2022 were collected. The Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and modified RECIST (mRECIST) standard were used to evaluate the therapeutic effect. The progression-free survival (PFS) and overall survival (OS) of the two groups were compared. Blood samples were collected before and after treatment to detect the changes of biochemical indicators, and the adverse events (AEs) related to treatment were recorded.

RESULTS

A total of 165 patients were included in the study, including 80 patients receiving TACE-L-P treatment and 85 patients receiving TACE-S-P. Patients in the TACE-L-P group had longer median OS (21.7 months vs. 15.6 months, P = 0.0027), longer median PFS (6.3 months vs. 3.2 months, P < 0.0001), higher objective response rate (41.25% vs. 30.59%, P = 0.008), and higher disease control rate (86.25% vs. 62.35%, P = 0.008) than those in the TACE-S-P group. Multivariate analysis of the TACE-L-P group showed that VP classification of PVTT, Child-Pugh grade, interleukin-17 (IL-17), vascular endothelial growth factor (VEGF), procalcitonin (PCT), and C-reactive protein (CRP) were independent factors significantly affecting patients' OS (P < 0.05). There was no significant difference in the incidence and severity of AEs between the two groups.

CONCLUSION

TACE-L-P treatment can improve the survival of patients with HCC and PVTT with an acceptable safety, but higher inflammatory indicators will affect the therapeutic effect.

Influence of Lenvatinib on the Functional Reprogramming of Peripheral Myeloid Cells in the Context of Non-Medullary Thyroid Carcinoma

Lenvatinib is a multitarget tyrosine kinase inhibitor (TKI) approved for the treatment of several types of cancers, including metastatic differentiated thyroid cancer (DTC). The intended targets include VEGFR 1-3, FGFR 1-4, PDGFRα, RET, and KIT signaling pathways, but drug resistance inevitably develops and a complete cure is very rare. Recent data has revealed that most of the TKIs have additional 'off-target' immunological effects, which might contribute to a protective antitumor immune response; however, human cellular data are lacking regarding Lenvatinib-mediated immunomodulation in DTC. Here, we investigated in ex vivo models the impact of Lenvatinib on the function of immune cells in healthy volunteers. We found that monocytes and macrophages were particularly susceptible to Lenvatinib, while neutrophiles and lymphocytes were less affected. In tumor-immune cell co-culture experiments, Lenvatinib exerted a broad inhibitory effect on the proinflammatory response in TC-induced macrophages. Interestingly, Lenvatinib-treated cells had decreased cellular M2 membrane markers, whereas they secreted a significantly higher level of the anti-inflammatory cytokine IL-10 upon LPS stimulation. In addition, prolonged exposure to Lenvatinib impaired macrophages survival and phenotypical differentiation, which was accompanied by remarkable morphological changes and suppressed cellular metabolic activity. These effects were mediated by myeloid cell-intrinsic mechanisms which are independent of Lenvatinib's on-target activity. Finally, using specific inhibitors, we argue that dual effects on p38 MAPK and Syk pathways are likely the underlying mechanism of the off-target immunological effects we observed in this study. Collectively, our data show the immunomodulatory properties of Lenvatinib on human monocytes. These insights could be harnessed for the future design of novel treatment strategies involving a combination of Lenvatinib with other immunotherapeutic agents.

Regulatory T cells and their associated factors in hepatocellular carcinoma development and therapy

Liver cancer is the third leading cause of cancer-related death worldwide with primary type hepatocellular carcinoma (HCC). Factors, including carcinogens, infection of hepatitis viruses, alcohol abuse, and non-alcoholic fatty liver disease (NAFLD), can induce HCC initiation and promote HCC progression. The prevalence of NAFLD accompanying the increased incidence of obesity and type 2 diabetes becomes the most increasing factor causing HCC worldwide. However, the benefit of current therapeutic options is still limited. Intrahepatic immunity plays critically important roles in HCC initiation, development, and progression. Regulatory T cells (Tregs) and their associated factors such as metabolites and secreting cytokines mediate the immune tolerance of the tumor microenvironment in HCC. Therefore, targeting Tregs and blocking their mediated factors may prevent HCC progression. This review summarizes the functions of Tregs in HCC-inducing factors including alcoholic and NAFLD, liver fibrosis, cirrhosis, and viral infections. Overall, a better understanding of the role of Tregs in the development and progression of HCC provides treatment strategies for liver cancer treatment.

Modulation of the tumour microenvironment in hepatocellular carcinoma by tyrosine kinase inhibitors: from modulation to combination therapy targeting the microenvironment

Hepatocellular carcinoma (HCC) is the third leading cause of cancer deaths worldwide. Tyrosine kinase inhibitors (TKIs) remain the backbone of systematic therapy for advanced hepatocellular carcinoma. Sorafenib and lenvatinib are currently approved as first-line therapeutic drugs, and regorafenib and cabozantinib are applied as second-line treatments. With inhibition of angiogenesis as the main target, TKIs exert a profound effect on the tumour microenvironment (TME). The TME is a complex mixture of cellular and noncellular components surrounding the tumour mass, and is associated with tumour progression partially through the epithelial-mesenchymal transition. Specifically, the TME of HCC is characterized by profound extracellular matrix remodelling and an immunosuppressive microenvironment. The purpose of this review is to provide a summary of TME remodelling mediated by four Food and Drug Administration approved TKIs in HCC and thus summarize the rationale and potential targets for combination therapy. The modulatory effect of TKIs on the TME of HCC was reported to enhance the antitumour effect of TKIs through pyroptosis of macrophages and subsequent natural killer cell activation, T cell activation, regulatory T cell reduction in HCC. Meanwhile, TKIs also induce drug resistance via M2 polarization and accumulation, recruitment of tumour-associated neutrophils, and induction of the epithelial-mesenchymal transition. In conclusion, the effect of TKIs on TME can enhance its antitumour effect, but might also partially contribute to the drug resistance that hinders the progression of TKIs as treatment for HCC. Additionally, the effect of TKIs also provides the rationale for combination therapy, including combining TKIs with immune checkpoint inhibitors, to facilitate increased drug efficacy of TKIs.

The immunomodulatory activity of lenvatinib prompts the survival of patients with advanced hepatocellular carcinoma

BACKGROUND

Lenvatinib is a novel multiple receptor tyrosine kinase inhibitor used for hepatocellular carcinoma (HCC) treatment. Although its main function is to suppress VEGFR and FGFR pathway, its immunomodulatory activity in HCC is not elucidated. Thus, this study aimed to investigate the immunomodulatory capability of lenvatinib in HCC.

MATERIAL AND METHODS

Totally 47 patients with HCC were enrolled in this study, and the immune cells and serum cytokine profiles before initiation of treatment and after 1 and 3 months were measured. The immune checkpoint receptors on the immune cells were also evaluated. Kaplan-Meier survival estimate and log rank tests were used to assess the prognostic value.

RESULT

The frequency of T helper (Th) cells and T regulatory (Treg) cells reduced after lenvatinib treatment, while cytotoxic T lymphocyte (CTL) cells increased significantly. The cytokine profiles showed IL-2, IL-5, IFN-γ increased; other cytokines including IL-6, IL-10, TNF- α and TNF- β decreased with lenvatinib therapy. Furthermore, the PD-1 and TIM-3 expressed on CTL had greatly decreased; the expression of TIM-3 and CTLA-4 was reduced on Treg cells as well. Besides, the new index CTL/Treg ratio was created, and low ratio was associated with the unfavorable outcome of HCC patients.

CONCLUSION

Our results confirmed that lenvatinib is capable of improving patients' immune status, saving the effector cells from exhaustion status and inhibiting the number and function of immunosuppressive cells. The novel index CTL/Treg ratio qualifies as a predictor for the outcome of patients with lenvatinib therapy.