Disruption of SLFN11 Deficiency-Induced CCL2 Signaling and Macrophage M2 Polarization Potentiates Anti-PD-1 Therapy Efficacy in Hepatocellular Carcinoma.

BACKGROUND & AIMS: The therapeutic effect of immune checkpoint inhibitors (ICIs) is poor in hepatocellular carcinoma (HCC) and varies greatly among individuals. Schlafen (SLFN) family members have important functions in immunity and oncology, but their roles in cancer immunobiology remain unclear. We aimed to investigate the role of the SLFN family in immune responses against HCC. METHODS: Transcriptome analysis was performed in human HCC tissues with or without response to ICIs. A humanized orthotopic HCC mouse model and a co-culture system were constructed, and cytometry by time-of-flight technology was used to explore the function and mechanism of SLFN11 in the immune context of HCC. RESULTS: SLFN11 was significantly up-regulated in tumors that responded to ICIs. Tumor-specific SLFN11 deficiency increased the infiltration of immunosuppressive macrophages and aggravated HCC progression. HCC cells with SLFN11 knockdown promoted macrophage migration and M2-like polarization in a C-C motif chemokine ligand 2-dependent manner, which in turn elevated their own PD-L1 expression by activating the nuclear factor-κB pathway. Mechanistically, SLFN11 suppressed the Notch pathway and C-C motif chemokine ligand 2 transcription by binding competitively with tripartite motif containing 21 to the RNA recognition motif 2 domain of RBM10, thereby inhibiting tripartite motif containing 21-mediated RBM10 degradation to stabilize RBM10 and promote NUMB exon 9 skipping. Pharmacologic antagonism of C-C motif chemokine receptor 2 potentiated the antitumor effect of anti-PD-1 in humanized mice bearing SLFN11 knockdown tumors. ICIs were more effective in patients with HCC with high serum SLFN11 levels. CONCLUSIONS: SLFN11 serves as a critical regulator of microenvironmental immune properties and an effective predictive biomarker of ICIs response in HCC. Blockade of C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 signaling sensitized SLFN11low HCC patients to ICI treatment.

Chemokine CCL21 determines immunotherapy response in hepatocellular carcinoma by affecting neutrophil polarization.

BACKGROUND: The efficacy of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) is poor and great heterogeneity among individuals. Chemokines are highly correlated with tumor immune response. Here, we aimed to identify an effective chemokine for predicting the efficacy of immunotherapy in HCC. METHODS: Chemokine C-C motif ligand 21 (CCL21) was screened by transcriptomic analysis in tumor tissues from HCC patients with different responses to ICIs. The least absolute shrinkage and selection operator (LASSO) regression analysis was conducted to construct a predictive nomogram. Neutrophils in vitro and HCC subcutaneous tumor model in vivo were applied to explore the role of CCL21 on the tumor microenvironment (TME) of HCC. RESULTS: Transcriptome analysis showed that CCL21 level was much higher in HCC patients with response to immunotherapy. The predictive nomogram was constructed and validated as a classifier. CCL21 could inhibit N2 neutrophil polarization by suppressing the activation of nuclear factor kappa B (NF-κB) pathway. In addition, CCL21 enhanced the therapeutic efficacy of ICIs. CONCLUSION: CCL21 may serve as a predictive biomarker for immunotherapy response in HCC patients. High levels of CCL21 in TME inhibit immunosuppressive polarization of neutrophils. CCL21 in combination with ICIs may offer a novel therapeutic strategy for HCC.

Hepatectomy After Conversion Therapy Using Tyrosine Kinase Inhibitors Plus Anti-PD-1 Antibody Therapy for Patients with Unresectable Hepatocellular Carcinoma.

BACKGROUND: Combined treatment with tyrosine kinase inhibitors (TKI) plus anti-PD-1 antibodies showed high anti-tumor efficacy and made conversion resection possible for patients with unresectable hepatocellular carcinoma (HCC). However, long-term survival has not been reported. METHODS: A cohort of consecutive patients who received combined TKI/anti-PD-1 antibodies as first-line treatment for initially unresectable HCC at the authors' hospital between August 2018 and September 2020 was eligible for this study. Patients who were responding to systemic therapy and met the criteria for hepatectomy underwent liver resection with curative intention. The study also investigated the association of clinical factors with successful conversion resection and postoperative recurrence. RESULTS: The study enrolled 101 patients including 24 patients (23.8 %) who underwent R0 resection a median of 3.9 months (interquartile range: 2.5-5.9 months) after initiation of systemic therapy. Patients with an Eastern cooperative oncology group performance status of 0, fewer intrahepatic tumors, or a radiographic response to systemic therapy were more likely to be able to receive curative resection. After a median follow-up period of 21.5 months, hepatectomy was independently associated with a favorable overall survival (hazard ratio [HR], 0.050; 95 % confidence interval [CI], 0.007-0.365; P = 0.003). For the 24 patients who underwent surgery, the 12-month recurrence-free survival and overall survival rates were respectively 75% and 95.8%. Achieving a pathologic complete response (n = 10) to systemic therapy was associated with a favorable recurrence-free survival after resection, with a trend toward significance (HR, 0.345; 95% CI, 0.067-1.785; P = 0.187). CONCLUSIONS: Selected patients with initially unresectable HCC can undergo hepatectomy after systemic therapy with combined TKI/anti-PD-1 antibodies. In this study, conversion resection was associated with a favorable prognosis.

Radiographic and α-fetoprotein response predict pathologic complete response to immunotherapy plus a TKI in hepatocellular carcinoma: a multicenter study.

BACKGROUND: Pathologic complete response (pCR) following preoperative systemic therapy is associated with improved outcomes after subsequent liver transplant/resection in hepatocellular carcinoma (HCC). However, the relationship between radiographic and histopathological response remains unclear. METHODS: We retrospectively examined patients with initially unresectable HCC who received tyrosine kinase inhibitor (TKI) plus anti-programmed death 1 (PD-1) therapy before undergoing liver resection between March 2019 and September 2021 across 7 hospitals in China. Radiographic response was evaluated using mRECIST. A pCR was defined as no viable tumor cells in resected samples. RESULTS: We included 35 eligible patients, of whom 15 (42.9%) achieved pCR after systemic therapy. After a median follow-up of 13.2 months, tumors recurred in 8 non-pCR and 1 pCR patient. Before resection, there were 6 complete responses, 24 partial responses, 4 stable disease cases, and 1 progressive disease case, per mRECIST. Predicting pCR by radiographic response yielded an area under the receiver operating characteristic curve (AUC) of 0.727 (95% CI: 0.558-0.902), with an optimal cutoff value of 80% reduction in the enhanced area in MRI (called major radiographic response), which had a 66.7% sensitivity, 85.0% specificity, and a 77.1% diagnostic accuracy. When radiographic response was combined with α-fetoprotein response, the AUC was 0.926 (95% CI: 0.785-0.999); the optimal cutoff value was 0.446, which had a 91.7% sensitivity, 84.6%, specificity, and an 88.0% diagnostic accuracy. CONCLUSIONS: In patients with unresectable HCC receiving combined TKI/anti-PD 1 therapy, major radiographic response alone or combined with α-fetoprotein response may predict pCR.

An mALBI-Child-Pugh-based nomogram for predicting post-hepatectomy liver failure grade B-C in patients with huge hepatocellular carcinoma: a multi-institutional study.

OBJECTIVE: Post-hepatectomy liver failure (PHLF) is a severe complication in patients with hepatocellular carcinoma (HCC) who underwent hepatectomy. This study aims to develop a nomogram of PHLF grade B-C in patients with huge HCC (diameter ≥ 10 cm). METHODS: We retrospectively collected clinical information of 514 and 97 patients who underwent hepatectomy for huge HCC at two medical centers between 2016 and 2021. Univariate and multivariate analysis were carried out to screen the independent risk factors of PHLF grade B-C, which were visualized as a nomogram. RESULTS: Three Hundred Forty Three Thousand One Hundred Seventy One  and 97 HCC patients were included in the training cohort, internal validation cohort, and external validation cohort, with probabilities of PHLF grade B-C of 15.1%, 12.9%, and 22.7%, respectively. Pre-operative modified albumin-bilirubin (mALBI) grade (p < 0.001), Child-Pugh classification (p = 0.044), international normalized ratio (INR) (p = 0.005), cirrhosis (p = 0.019), and intraoperative blood loss (p = 0.004) were found to be independently associated with PHLF grade B-C in the training cohort. All the five independent factors were considered in the establishment of the nomogram model. In the internal validation cohort and external validation cohort, the area under receiver operating characteristic curve for the nomogram in PHLF grade B-C prediction reached 0.823 and 0.740, respectively. Divided into different risk groups according to the optimal cut-off value, patients in the high-risk group reported significantly higher frequency of PHLF grade B-C than those in the low-risk group, both in the training cohort and the validation cohort (p < 0.001). CONCLUSIONS: The proposed noninvasive nomogram based on mALBI-Child-Pugh and three other indicators achieved optimal prediction performance of PHLF grade B-C in patients with huge HCC.

Future liver volume combined with platelet count predicts liver failure after major hepatectomy.

BACKGROUND: Major hepatectomy is associated with high incidence of post-hepatectomy liver failure (PHLF). This study aimed to evaluate the effect of future remnant liver volume combined with liver function tests on predicting PHLF. METHODS: Patients who underwent major hepatectomy from April 2009 to May 2017 were enrolled in the training cohort. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors of PHLF and generate a logistic regression model for the prediction of PHLF. A conditional inference tree was generated based on the optimal cutoff value of independent predictive factors of PHLF. The precedent results were validated in an independent cohort from June 2017 to March 2018. RESULTS: One hundred and eighteen patients were included in the training cohort, while another 34 in the validation cohort. Future remnant liver volume/estimated standard total liver volume (FLV/eTV) and preoperative platelet count were independent predictive factors of PHLF (P = 0.0021 and P = 0.012, respectively). The conditional inference tree showed that patients with FLV/eTV ≤0.56 and PLT count ≤145 × 109/L were at high risk of developing PHLF. CONCLUSION: FLV/eTV combined with preoperative PLT count is effective in predicting PHLF after major hepatectomy.

Increase of Portal Vein Pressure Gradient After Hepatectomy Predicts Post-operative Liver Dysfunction.

Background. Post-hepatectomy liver failure (PHLF) is an important cause of mortality and morbidity. Whether Child-Pugh A patients with varying degrees of cirrhosis are good candidates for hepatectomy is disputed. The purpose of this study was to analyze the impact of portal venous pressure gradient (PVPG) variation during surgery on PHLF. Methods. PVPG, the pressure gradient between the portal vein and central vein, was measured in consecutive patients before and after liver resection. The optimal cutoff of PVPG to predict PHLF was determined by receiver operating characteristic curve analysis. Risk factors for PHLF were subjected to univariate and multivariable analysis. Results. Sixty Child-Pugh A patients were recruited. The mean PVPG was increased from 5.17 ± 4.78 mm of mercury (mmHg) to 6.37 ± 4.44 mmHg after liver resection. The optimal cutoff value of PVPG increments to predict PHLF was 1.5 mmHg. Multivariable analysis showed prothrombin time (PT), post-hepatectomy PVPG increments of 1.5 mmHg or greater, and resected liver segments of 3 or more to be independent predictors of PHLF. Conclusions. Acute PVPG increase after hepatectomy is associated with a higher risk of PHLF in Child-Pugh A patients.

CircRNA UBAP2 serves as a sponge of miR-1294 to increase tumorigenesis in hepatocellular carcinoma through regulating c-Myc expression.

Circular RNAs (circRNAs) are a class of regulatory RNAs with complex roles in healthy and diseased tissues. However, the oncogenic role of circRNAs in hepatocellular carcinoma (HCC) remains poorly understood, including the mechanisms by which the circular ubiquitin-binding associated protein 2 (circUBAP2) contributes to tumorigenesis. We analyzed the expression of circUBAP2 in 20 paired samples of HCC and healthy tissue as well as in seven HCC cell lines via quantitative real-time polymerase chain reaction. Functional experiments, such as CCK8 viability assays, colony formation assays, wound healing, transwell assays and flow cytometry, were conducted to assess the effects of circUBAP2 in vitro. To further elucidate the mechanisms by which circUBAP2 acts, we conducted dual-luciferase assays, western blots, RNA pull-down assays and rescue experiments. CircUBAP2 was highly upregulated in most HCC tissues and was associated with poor prognosis. HCC patients with high circUBAP2 expression had greater vascular invasion and worse differentiation. Functionally, circUBAP2 overexpression enhanced HCC cell proliferation, migration and invasion and inhibited apoptosis. Furthermore, we found that circUBAP2 upregulated c-Myc expression by sponging miR-1294, thus contributing to hepatocarcinogenesis. Inhibiting circUBAP2 expression in HCC attenuated the oncogenic effects of c-Myc. These findings suggest that circUBAP2 promotes HCC growth and metastasis. CircUBAP2 may have value as an independent prognostic biomarker or as a new target for the treatment of HCC.

Do the existing staging systems for primary liver cancer apply to combined hepatocellular carcinoma-intrahepatic cholangiocarcinoma?

BACKGROUND: The incidence of combined hepatocellular carcinoma-intrahepatic cholangiocarcinoma (cHCC-ICC) is relatively low, and the knowledge about the prognosis of cHCC-ICC remains obscure. In the study, we aimed to screen existing primary liver cancer staging systems and shed light on the prognosis and risk factors for cHCC-ICC. METHODS: We retrospectively reviewed 206 cHCC-ICC patients who received curative surgical resection from April 1999 to March 2017. The correlation of survival measures with the histological types or with tumor staging systems was determined and predictive values of tumor staging systems with cHCC-ICC prognosis were compared. RESULTS: The histological type was not associated with overall survival (OS) (P = 0.338) or disease-free survival (DFS) (P = 0.843) of patients after curative surgical resection. BCLC, TNM for HCC, and TNM for ICC stages correlated with both OS and DFS in cHCC-ICC (all P < 0.05). The predictive values of TNM for HCC and TNM for ICC stages were similar in terms of predicting postoperative OS (P = 0.798) and DFS (P = 0.191) in cHCC-ICC. TNM for HCC was superior to BCLC for predicting postoperative OS (P = 0.022) in cHCC-ICC. CONCLUSION: The TNM for HCC staging system should be prioritized for clinical applications in predicting cHCC-ICC prognosis.

Microvascular invasion has limited clinical values in hepatocellular carcinoma patients at Barcelona Clinic Liver Cancer (BCLC) stages 0 or B.

BACKGROUND: Microvascular invasion (MVI) is recognized as a prognostic factor associated with poor outcome in hepatocellular carcinoma (HCC) patients after curative resection. It remains unclear, however, whether MVI can provide prognostic information for patients at a specific tumor stage. METHODS: Consecutive HCC patients who underwent curative resection in years of 2007 and 2008 (discovery cohort) were enrolled in this retrospective study. Patients were stratified by the Barcelona Clinic Liver Cancer (BCLC) staging system. The prognostic significance of MVI for overall survival (OS) and recurrence-free survival (RFS) was studied in each subgroup. The clinical significance of MVI was validated in another cohort of patients underwent curative surgery in the year of 2006 (validation cohort). RESULTS: Of the 1540 patients in the discovery cohort, 389 (25.3%) patients had detectable MVI. Occurrence rates of MVI in the BCLC stage 0, A, and B subgroups were 12.4, 26.2, and 34.4%, respectively. In univariate analysis, MVI was associated with poor OS and RFS (P < 0.001 for both) in HCC patients at stage A, with poor OS in patients at stage 0 (P = 0.028), and with poor RFS at stage B (P = 0.039). In multivariate analysis, MVI was an independent risk factor for OS (HR = 1.431, 95% CI, 1.163-1.761, P < 0.001) and RFS (HR = 1.400, 95% CI, 1.150-1.705, P = 0.001) in patients at stage A; and an independent risk factor for RFS (P = 0.043) in patients at stage B. A similar clinical significance of MVI was found in the validation cohort. CONCLUSIONS: MVI has limited prognostic value for HCC patients at BCLC stages 0 and B. For those at stage A, MVI was associated with patient survival and may help to select patients with high risk of disease recurrence.

High levels of hepatitis B surface antigen are associated with poorer survival and early recurrence of hepatocellular carcinoma in patients with low hepatitis B viral loads.

PURPOSE: Recurrence is a disastrous outcome in patients with hepatitis-related hepatocellular carcinoma (HCC) who have undergone curative resection, and little is known about whether high levels of hepatitis B surface antigen (HBsAg) increase the risk of HCC recurrence. PATIENTS AND METHODS: This retrospective study included 1,360 HBsAg-positive postoperative HCC patients with hepatitis B viral (HBV) DNA levels < 2000 IU/mL, including 298 patients in a training cohort and 1,062 patients in a validation cohort. The prognostic value of the HBsAg level was evaluated using Cox regression and Kaplan-Meier analyses. RESULTS: We demonstrated that 1,000 IU/mL, but not 10 or 100 IU/mL, was a meaningful cutoff level for significantly discriminating these patients into an HBsAg(Low) group and an HBsAg(High) group based on correlations between the HBsAg level and liver cirrhosis (p = 0.028), tumor size (p = 0.039), and hepatitis B e antigen level (p < 0.001). The postoperative 1-, 3-, and 5-year overall survival (OS) rates of HCC patients in the HBsAg(Low) group were significantly higher than those of HCC patients in the HBsAg(High) group. Accordingly, the 5-year recurrence-free survival (RFS) rates of patients in the HBsAg(Low) group were markedly higher than those of HCC patients in the HBsAg(High) group. The HBsAg level was a prognostic indicator for OS (p = 0.014) and RFS (p = 0.01). CONCLUSION: HBsAg level is correlated with more aggressive tumor behavior and serves as a prognostic indicator in patients with surgically resected HCC with low HBV load.

Cholelithiasis and the risk of intrahepatic cholangiocarcinoma: a meta-analysis of observational studies.

BACKGROUND: The etiological factor for intrahepatic cholangiocarcinoma (ICC) is not clear. Although it has been widely accepted that intrahepatic biliary tree stone is associated with increased risk of ICC, the role of extrahepatic biliary tree stone in the incidence of ICC is controversial. In the present study we aim to evaluate the association between pre-existing choledocholithiasis and cholecystolithiasis and the risk of ICC. METHODS: PubMed, Embase, and Web of Science were searched to identify cohort and case-control studies on the association between choledocholithiasis or cholecystolithiasis and the risk of ICC. Studies that met the inclusion criteria were subjected to a meta-analysis performed with Stata statistical software. Either a fixed or random effect model was used, depending on the heterogeneity within the studies. Egger's test was performed to assess publication bias. RESULTS: Seven case-control studies met our inclusion criteria. Of the 123,771 participants, 4763 (3.85 %) were patients with ICC, and 119,008 were tumor-free controls. The presence of pre-existing bile duct stones (choledocholithiasis alone or choledocholithiasis accompanied by hepatolithiasis) was associated with the risk of ICC (odds ratio [OR] 17.64, 95 % confidence interval [CI] 11.14-27.95). Even the presence of choledocholithiasis alone (in the absence of hepatolithiasis) was associated with a high risk of ICC (OR 11.79, 95 % CI 4.17-33.35). Cholecystolithiasis may possibly contributed to the incidence of ICC (OR 2.00, 95 % CI 1.16-3.42), with large heterogeneity within studies (I (2) = 78.5 %). CONCLUSIONS: Bile duct stones including choledocholithiasis are important risk factors for ICC. Careful surveillance of patients with extrahepatic biliary tree stone should be considered.

Quantitative assessment of the effect of glutathione S-transferase genes GSTM1 and GSTT1 on hepatocellular carcinoma risk.

Hepatocellular carcinoma (HCC) is one of the most serious health problems worldwide. As in many other diseases, environment and genetic factors are believed to be involved in the pathogenesis of HCC. Numerous epidemiologic investigations including case-control and cohort studies have suggested the association of glutathione S-transferase (GST) genetic polymorphisms and HCC risk. However, some studies have produced conflicting results. Therefore, we performed an updated meta-analysis to clarify this inconsistency and to establish a comprehensive picture of the association of the polymorphisms of GSTM1 and GSTT1 with HCC susceptibility. We searched PubMed, Embase, ISI Web of Science, and CNKI databases to identify eligible studies meeting the inclusion criteria up to August 30, 2013. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of association. Finally, there were a total of 33 studies with 4,232 cases and 6,601 controls included in this meta-analysis. In the pooled analysis, significantly increased HCC risks were found for null genotype of GSTM1 (OR = 1.31, 95% CI = 1.07-1.61, P = 0.010, P heterogeneity < 10(-5)) and GSTT1 (OR = 1.47, 95% CI = 1.25-1.74, P < 10(-5), P heterogeneity < 10(-5)). Potential sources of heterogeneity were explored by subgroup analysis based on ethnicity, sample size, and source of control. Significant results were found among East Asians and Indians when stratified by ethnicity, while no evidence of significant associations was observed among Caucasian and African populations. In the gene-gene interaction analysis, a statistically significant increased risk for HCC was detected for individuals with combined deletion mutations in both genes compared to those with wild genotypes (OR = 1.88, 95% CI = 1.41-2.50, P < 10(-4), P heterogeneity = 0.004). The present meta-analysis demonstrated that the GSTM1 and GSTT1 null genotype may be associated with an increased risk of HCC and that individuals having the combination of both defective GST genotypes may be more susceptible to developing HCC.

CXCL9 Overexpression Predicts Better HCC Response to Anti-PD-1 Therapy and Promotes N1 Polarization of Neutrophils.

Background: Anti-programmed death-1 (PD1) antibodies have changed the treatment landscape for hepatocellular carcinoma (HCC) and exhibit promising treatment efficacy. However, the majority of HCCs still do not respond to anti-PD-1 therapy. Methods: We analyzed the expression of CXCL9 in blood samples from patients who received anti-PD-1 therapy and evaluated its correlation with clinicopathological characteristics and treatment outcomes. Based on the results of Cox regression analysis, a nomogram was established for predicting HCC response to anti-PD-1 therapy. qRT‒PCR and multiple immunofluorescence assays were utilized to analyze the proportions of N1-type neutrophils in vitro and in tumor samples, respectively. Results: The nomogram showed good predictive efficacy in the training and validation cohorts and may be useful for guiding clinical treatment of HCC patients. We also found that HCC cell-derived CXCL9 promoted N1 polarization of neutrophils in vitro and that AMG487, a specific CXCR3 inhibitor, significantly blocked this process. Moreover, multiple immunofluorescence (mIF) showed that patients with higher serum CXCL9 levels had greater infiltration of the N1 phenotype of tumor-associated neutrophils (TANs). Conclusion: Our study highlights the critical role of CXCL9 as an effective biomarker of immunotherapy efficacy and in promoting the polarization of N1-type neutrophils; thus, targeting the CXCL9-CXCR3 axis could represent a novel pharmaceutical strategy to enhance immunotherapy for HCC.

Platelet-to-lymphocyte ratio predicts tumor response and survival of patients with hepatocellular carcinoma undergoing immunotherapies.

BACKGROUND: Lymphocyte-related factors were associated with survival outcome of different types of cancers. Nevertheless, the association between lymphocytes-related factors and tumor response of immunotherapy remains unclear. METHODS: This is a retrospective study. Eligible participants included patients with unresectable or advanced hepatocellular carcinoma (HCC) who underwent immunotherapy as their first-line treatment. Radiological assessment of tumor response adhered to RECIST 1.1 and HCC-specific modified RECIST (mRECIST) criteria. Univariate and multivariate logistic analyses were employed to analyze clinical factors associated with tumor response. Kaplan-Meier survivial analysis were employed to compare progression-free survival (PFS) and overall survival (OS) across different clinical factors. Furthermore, patients who received treatment with either a combination of bevacizumab and anti-PD-1(L1) antibody (Beva group) or tyrosine-kinase inhibitor (TKI) and anti-PD-1 antibody (TKI group) were examined to explore the relation between clinical factors and tumor response. RESULTS: A total of 208 patients were enrolled in this study. The median PFS and OS were 9.84 months and 24.44 months,respectively. An independent factor associated with a more favorable tumor response to immunotherapy was identified when PLR<100. Patients with PLR<100 had longer PFS than other patients, while OS showed no significant difference. Further analysis revealed that PLR exhibited superior prognostic value in patients of the Beva group as compared to those in the TKI group. CONCLUSIONS: There exisits an association between PLR and tumor response as well as survival outcomes in patients receiving immunotherapy, particularly those treated with the combination of bevacizumab and anti-PD-1.

Repolarization of Immunosuppressive Macrophages by Targeting SLAMF7-Regulated CCL2 Signaling Sensitizes Hepatocellular Carcinoma to Immunotherapy.

Immune checkpoint inhibitors have limited efficacy in hepatocellular carcinoma (HCC). Macrophages are the most abundant immune cells in HCC, suggesting that a better understanding of the intrinsic processes by which tumor cells regulate macrophages could help identify strategies to improve response to immunotherapy. As signaling lymphocytic activation molecule (SLAM) family members regulate various immune functions, we investigated the role of specific SLAM receptors in the immunobiology of HCC. Comparison of the transcriptomic landscapes of immunotherapy-responsive and nonresponsive patients with advanced HCC identified SLAMF7 upregulation in immunotherapy-responsive HCC, and patients with HCC who responded to immunotherapy also displayed higher serum levels of SLAMF7. Loss of Slamf7 in liver-specific knockout mice led to increased hepatocarcinogenesis and metastasis, elevated immunosuppressive macrophage infiltration, and upregulated PD-1 expression in CD8+ T cells. HCC cell-intrinsic SLAMF7 suppressed MAPK/ATF2-mediated CCL2 expression to regulate macrophage migration and polarization in vitro. Mechanistically, SLAMF7 associated with SH2 domain-containing adaptor protein B (SHB) through its cytoplasmic 304 tyrosine site to facilitate the recruitment of SHIP1 to SLAMF7 and inhibit the ubiquitination of TRAF6, thereby attenuating MAPK pathway activation and CCL2 transcription. Pharmacological antagonism of the CCL2/CCR2 axis potentiated the therapeutic effect of anti-PD-1 antibody in orthotopic HCC mouse models with low SLAMF7 expression. In conclusion, this study highlights SLAMF7 as a regulator of macrophage function and a potential predictive biomarker of immunotherapy response in HCC. Strategies targeting CCL2 signaling to induce macrophage repolarization in HCC with low SLAMF7 might enhance the efficacy of immunotherapy. SIGNIFICANCE: CCL2 upregulation caused by SLAMF7 deficiency in hepatocellular carcinoma cells induces immunosuppressive macrophage polarization and confers resistance to immune checkpoint blockade, providing potential biomarkers and targets to improve immunotherapy response in patients.

Effectiveness and safety of lenvatinib plus anti-programmed death-1 antibodies in patients with hepatocellular carcinoma: A real-world cohort study.

OBJECTIVE: Lenvatinib plus anti-programmed death-1 (anti-PD-1) antibody combinations have shown potent anti-tumor effect in phase I/II trials in advanced or unresectable hepatocellular carcinoma (HCC), but real-world data are limited. METHODS: To investigate the effectiveness and safety of lenvatinib plus anti-PD-1 antibodies in a real-world cohort, we retrospectively evaluated 210 patients with unresectable or advanced HCC treated with these regimens between October 2018 and February 2022. RESULTS: The objective response rate and disease control rate per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 were 28.1% and 75.2%. Median overall survival (OS) and progression-free survival (PFS) in the overall cohort were 17.2 and 8.4 months, respectively. Median OS and PFS of patients receiving first-line treatment reached 18.9 and 9.6 months. Median OS was significantly longer in patients with Child-Pugh class A versus B (18.8 vs. 5.9 months, respectively), as was median PFS (9.1 vs. 4.4 months). Patients with albumin-bilirubin (ALBI) grade 1 versus grade 2/3 also had significantly greater median OS (23.5 vs. 13.4 months). Treatment-related adverse events (AEs) occurred in 79.5% of patients. Patients with ALBI grade 2/3 had a higher rate of grade 3/4 AEs than patients with ALBI grade 1 (57.5% vs. 38.5%). CONCLUSION: Lenvatinib combined with anti-PD-1 antibody therapy was effective in patients with sufficient liver function reserve. Further study is needed to improve therapeutic efficacy and AE management in patients with Child-Pugh class B or ALBI grade 2/3.

Intratumoral PPT1-positive macrophages determine immunosuppressive contexture and immunotherapy response in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignancy with limited treatment options and poor prognosis. Macrophages are enriched in the HCC microenvironment and have a significant impact on disease progression and therapy efficacy. We aim to identify critical macrophages subsets involved in HCC development. METHODS: Macrophage-specific marker genes were identified through single-cell RNA sequencing analyses. The clinical significance of macrophages with palmitoyl-protein thioesterase 1 (PPT1) positive was investigated in 169 patients with HCC from Zhongshan Hospital using immunohistochemistry and immunofluorescence. The immune microenvironment of HCC and the functional phenotype of PPT1+ macrophages were explored using cytometry by time-of-flight (CyTOF) and RNA sequencing. RESULTS: Single-cell RNA sequencing analyses revealed that PPT1 was predominantly expressed in macrophages in HCC. Intratumoral PPT1+ macrophages abundance was associated with inferior survival durations of patients and an independent risk factor of prognosis for HCC. High throughput analyses of immune infiltrates showed that PPT1+ macrophage-enriched HCCs were characterized by high infiltration of CD8+ T cells with increased programmed death-1 (PD-1) expression. PPT1+ macrophages exhibited higher galectin-9, CD172a, and CCR2 levels but lower CD80 and CCR7 levels than PPT1- macrophages. Pharmacological inhibition of PPT1 by DC661 suppressed mitogen-activated protein kinase (MAPK) pathway activity but activated nuclear factor kappa B (NF-κB) pathway in macrophages. In addition, DC661 enhanced the therapeutic efficacy of anti-PD-1 antibody in the HCC mouse model. CONCLUSIONS: PPT1 is mainly expressed in macrophages in HCC and promotes immunosuppressive transformation of macrophages and tumor microenvironment. PPT1+ macrophage infiltration is associated with poor prognosis of patients with HCC. Targeting PPT1 may potentiate the efficacy of immunotherapy for HCC.

Functions of Key Enzymes of Glycolytic Metabolism in Tumor Microenvironment.

The tumor microenvironment (TME) plays a crucial role in tumor initiation, growth and metastasis. Metabolic enzymes involved in tumor glycolytic reprogramming, including hexokinase, pyruvate kinase, and lactate dehydrogenase, not only play key roles in tumorigenesis and maintaining tumor cell survival, but also take part in the modulation of the TME. Many studies have been devoted to the role of key glycolytic enzymes in the TME over the past decades. We summarize the studies on the role of glycolytic enzymes in the TME of these years and found that glycolytic enzymes remodel the TME primarily through regulating immune escape, angiogenesis, and affecting stromal cells and exosomes. Notably, abnormal tumor vascular system, peritumoral stromal cells, and tumor immunosuppressive microenvironment are important contributors to the failure of antitumor therapy. Therefore, we discuss the mechanisms of regulation by key glycolytic enzymes that may contribute to a promising biomarker for therapeutic intervention. We argue that targeting key glycolytic enzymes in combination with antiprogrammed cell death ligand 1 or antivascular endothelial growth factor could emerge as the more integrated and comprehensive antitumor treatment strategy.