Search

The upregulation of programmed death ligand 1 (PD-L1) plays a crucial role in facilitating cancer cells to evade immune surveillance through immunosuppression. However, the precise regulatory mechanisms of PD-L1 in hepatocellular carcinoma (HCC) remain undefined. The correlation between PD-L1 and ubiquitin-like molecules (UBLs) was studied using sequencing data from 20 HCC patients in our center, combined with TCGA data. Specifically, the association between FAT10 and PD-L1 was further validated at both the protein and mRNA levels in HCC tissues from our center. Subsequently, the effect of FAT10 on tumor progression and immune suppression was examined through both in vivo and in vitro experiments. Utilizing sequencing data, qPCR, and Western blotting assays, we confirmed that FAT10 was highly expressed in HCC tissues and positively correlated with PD-L1 expression. Additionally, in vitro experiments demonstrated that the overexpression of FAT10 fostered the proliferation, migration, and invasion of HCC cells. Furthermore, the overexpression of FAT10 in HCC cells led to an increase in PD-L1 expression, resulting in the inhibition of T cell proliferation and the enhancement of HCC cell resistance to T cell-mediated cytotoxicity. Moreover, in vivo experiments utilizing the C57BL/6 mouse model revealed that overexpression of FAT10 effectively suppressed the infiltration of CD8 + GZMB + and CD8 + Ki67 + T cells, as well as reduced serum levels of TNF-α and IFN-γ. Mechanistically, we further identified that FAT10 upregulates PD-L1 expression via activating the PI3K/AKT/mTOR pathway, but not in a ubiquitin-like modification. In conclusion, our findings indicate that FAT10 promotes immune evasion of HCC via upregulating PD-L1 expression, suggesting its potential as a novel target to enhance the efficiency of immunotherapy in HCC., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Although mRNA vaccines have shown certain clinical benefits in multiple malignancies, their therapeutic efficacies against hepatocellular carcinoma (HCC) remains uncertain. This study focused on establishing a novel risk score system based on immune subtypes so as to identify optimal HCC mRNA vaccination population., Methods: GEPIA, cBioPortal and TIMER databases were utilized to identify candidate genes for mRNA vaccination in HCC. Subsequently, immune subtypes were constructed based on the candidate genes. According to the differential expressed genes among various immune subtypes, a risk score system was established using machine learning algorithm. Besides, multi-color immunofluorescence of tumor tissues from 72 HCC patients were applied to validate the feasibility and efficiency of the risk score system., Results: Twelve overexpressed and mutated genes associated with poor survival and APCs infiltration were identified as potential candidate targets for mRNA vaccination. Three immune subtypes (e.g. IS1, IS2 and IS3) with distinct clinicopathological and molecular profiles were constructed according to the 12 candidate genes. Based on the immune subtype, a risk score system was developed, and according to the risk score from low to high, HCC patients were classified into four subgroups on average (e.g. RS1, RS2, RS3 and RS4). RS4 mainly overlapped with IS3, RS1 with IS2, and RS2+RS3 with IS1. ROC analysis also suggested the significant capacity of the risk score to distinguish between the three immune subtypes. Higher risk score exhibited robustly predictive ability for worse survival, which was further independently proved by multi-color immunofluorescence of HCC samples. Notably, RS4 tumors exhibited an increased immunosuppressive phenotype, higher expression of the twelve potential candidate targets and increased genome altered fraction, and therefore might benefit more from vaccination., Conclusions: This novel risk score system based on immune subtypes enabled the identification of RS4 tumor that, due to its highly immunosuppressive microenvironment, may benefit from HCC mRNA vaccination., (© 2024. Springer Nature Switzerland AG.)

Background: Lenvatinib plus PD-1 inhibitors and interventional (LPI) therapy have demonstrated promising treatment effects in unresectable hepatocellular carcinoma (HCC). However, biomarkers for predicting the response to LPI therapy remain to be further explored. We aimed to develop a radiomics model to noninvasively predict the efficacy of LPI therapy., Methods: Clinical data of patients with HCC receiving LPI therapy were collected in our institution. The clinical model was built with clinical information. Nine machine learning classifiers were tested and the multilayer perceptron classifier with optimal performance was used as the radiomics model. The clinical-radiomics model was constructed by integrating clinical and radiomics scores through logistic regression analysis., Results: 151 patients were enrolled in this study (2:1 randomization, 101 and 50 in the training and validation cohorts), of which three achieved complete response, 69 showed partial response, 46 showed stable disease, and 33 showed progressive disease. The objective response rate, disease control rate, and conversion resection rates were 47.7, 78.1 and 23.2%. 14 features were selected from the initially extracted 1223 for radiomics model construction. The area under the curves of the radiomics model (0.900 for training and 0.893 for validation) were comparable to that of the clinical-radiomics model (0.912 for training and 0.892 for validation), and both were superior to the clinical model (0.669 for training and 0.585 for validation). Meanwhile, the radiomics model can categorize participants into high-risk and low-risk groups for progression-free survival (PFS) and overall survival (OS) in the training (HR 1.913, 95% CI 1.121 to 3.265, p=0.016 for PFS; HR 4.252, 95% CI 2.051 to 8.816, p=0.001 for OS) and validation sets (HR 2.347, 95% CI 1.095 to 5.031, p=0.012 for PFS; HR 2.592, 95% CI 1.050 to 6.394, p=0.019 for OS)., Conclusion: The promising machine learning radiomics model was developed and validated to predict the efficacy of LPI therapy for patients with HCC and perform risk stratification, with comparable performance to clinical-radiomics model., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Circular RNAs (circRNAs) have been implicated in tumorigenesis and progression of various cancers. However, the underlying mechanisms of circRNAs in hepatocellular carcinoma (HCC) have not been fully elucidated. Herein, a new oncogenic circRNA, hsa_circ_0070039 (circNUP54), was identified to be significantly upregulated in HCC through circRNA sequencing. As verified in 68 HCC samples, circNUP54 overexpression was correlated with aggressive cancerous behaviors and poor outcomes. Moreover, the function experiments showed that knockdown of circNUP54 inhibited the malignant progression of HCC in vitro and in vivo, whereas overexpression of circNUP54 had the opposite role. Mechanistic investigations carried out by RNA pull-down, RNA immunoprecipitation, and immunofluorescence revealed that circNUP54 interacted with the RNA-binding protein Hu-antigen R (HuR) and promoted its cytoplasmic export. The cytoplasmic accumulation of HuR stabilized the downstream BIRC3 mRNA through its binding to the 3' UTR region. Consequently, the encoded protein of BIRC3, cellular inhibitor of apoptosis 2 (cIAP2), proceeded to activate the NF-κB signal pathway and ultimately contributed to HCC progression. In addition, depletion of BIRC3 rescued the pro-tumorigenic effect of circNUP54 on HCC cells. Overall, this study demonstrated that circNUP54 facilitates HCC progression via regulating the HuR/BIRC3/NF-κB axis, which may serve as a promising therapeutic target for HCC treatment., (© 2024. The Author(s).)

Introduction: Lenvatinib has recently become available as the first-line therapy for advanced hepatocellular carcinoma (HCC), but its molecular mechanism in HCC remains largely unknown., Objectives: The current study aims to identify the molecular mechanisms of lenvatinib in HCC., Methods: Gene expression microarrays, flow cytometry, western blot, qRT-PCR, immunohistochemistry and immunofluorescence were used to study the response of HCC cells to lenvatinib. Xenograft tumor of Huh7 cells was also established to detect the effect of lenvatinib in vivo., Results: Herein, we found that lenvatinib could induce apoptosis via increasing reactive oxygen species (ROS) levels in HCC cells. Then, microarray analysis and qRT-PCR results confirmed that GPX2 was a vital target for lenvatinib against HCC. Loss and gain function of experiment showed that regulating GPX2 levels markedly affected the lenvatinib-induced ROS levels and apoptosis in HCC cells. In addition, analyses of The Cancer Genome Atlas database and the qRT-PCR results in our cohort both showed that GPX2 markedly overexpressed in tumor tissues and correlated with poor overall survival in HCC. Mechanistically, our findings further demonstrated that GPX2 was a downstream gene regulated by β-catenin, while lenvatinib could prevent nuclear translocation of β-catenin and further inhibit GPX2 expression in HCC cells. More importantly, the correlation of GPX2 expression with lenvatinib response was further analyzed in 22 HCC patients who received lenvatinib therapy, and the results showed that the objective response rate (ORR) in patients with low GPX2 expression was 44.4% (4/9), while the ORR in patients with high GPX2 levels was only 7.7% (1/13)., Conclusion: Our findings indicated that GPX2 plays an important role in lenvatinib-induced HCC cell apoptosis, which might serve as a biomarker for instruction of lenvatinib therapy in HCC patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Production and hosting by Elsevier B.V.)

Circular RNAs have been reported to play essential roles in the tumorigenesis and progression of various cancers. However, the biological processes and mechanisms involved in hepatocellular carcinoma (HCC) remain unclear. Initial RNA-sequencing data and qRT-PCR results in our cohort showed that hsa_circ_0072309 (also called circLIFR) was markedly downregulated in HCC tissues. Kaplan-Meier analysis indicated that higher levels of circLIFR in HCC patients correlated with favorable overall survival and recurrence-free survival rates. Both in vitro and in vivo experiments indicated that circLIFR inhibited the proliferation and invasion abilities of HCC cells. We therefore conducted related experiments to explore the mechanism of circLIFR in HCC. Fluorescence in situ hybridization results revealed that circLIFR was mainly located in the cytoplasm, and RNA immunoprecipitation assays indicated that circLIFR was significantly enriched by Ago2 protein. These results suggested that circLIFR may function as a sponge of miRNAs to regulate HCC progression. We further conducted bioinformatics prediction as well as dual-luciferase reporter assays, and the results of which showed that circLIFR could sponge miR-624-5p to stabilize glycogen synthase kinase 3β (GSK-3β) expression. Loss and gain of function experiments demonstrated that regulation of the expression of miR-624-5p or GSK-3β markedly affected HCC progression induced by circLIFR. Importantly, we also proved that circLIFR could facilitate the degradation of β-catenin and prevent its translocation to the nucleus in HCC cells. Overall, our study demonstrated that circLIFR acts as a tumor suppressor in HCC by regulating miR-624-5p and inactivating the GSK-3β/β-catenin signaling pathway., (© 2022. The Author(s).)

Background: Long noncoding RNAs (lncRNAs) are reported to play important roles in tumorigenesis of various malignant tumors. However, the clinical significance of aberrant lncRNA expression in hepatocellular carcinoma (HCC) is still elusive., Methods: Firstly, a differentially expressed lncRNA CTC-297N7.9 in HCC was detected by analyzing the data from The Cancer Genome Atlas (TCGA). Secondly, the expression level of CTC-297N7.9 was examined in four HCC cell lines and 60 pairs of HCC tissues by polymerase chain reaction (PCR) assay at our center. Thirdly, receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic value of CTC-297N7.9 for HCC. Correlation and survival analysis of HCC patients from the TCGA and our center were also carried out to assess the predictive value of CTC-297N7.9. Finally, survival prognostic models were established combining lncRNA expression and other clinical parameters., Results: The expression of CTC-297N7.9 was downregulated in HCC cell lines and HCC tissues. ROC curve revealed its significant diagnostic value in HCC. CTC-297N7.9 expression correlated with serum alpha-fetal protein (AFP), tumor stage, and tumor differentiation. Survival analysis indicated that overall survival (OS) and disease-free survival (DFS) are all positively associated with CTC-297N7.9 expression, especially in patients without viral hepatitis or cirrhosis. Cox regression analysis showed that CTC-297N7.9 expression level is an independent prognostic factor for both OS and DFS in HCC patients. Based on the model, CTC-297N7.9 was observed to be negatively correlated to risk score, indicating its role as a protective factor for HCC., Conclusion: Our study demonstrated that the low expression of CTC-297N7.9 is associated with poor prognosis in HCC patients, suggesting its possible role as a potential prognostic marker for HCC., (© 2019 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Background: The role of tumor necrosis factor alpha (TNF-α) in targeted therapy for hepatocellular carcinoma (HCC) remains largely unknown. The current study aimed to clarify the mechanistic effects of targeting TNF-α to overcome sorafenib resistance in HCC., Methods: A correlation of TNF-α expression with the prognosis was analyzed in 62 HCC patients who underwent surgical resection and subsequent received adjuvant sorafenib treatment. The relation of TNF-α expression and sorafenib sensitivity was determined in different HCC cell lines. The combined therapeutic effects of sorafenib and ulinastatin, which could inhibit TNF-α expression, on HCC were examined in vitro and in vivo., Findings: High TNF-α expression was correlated with poor outcomes in HCC patients who received adjuvant sorafenib after surgery. In vitro experiments showed that TNF-α promotes HCC cell resistant to sorafenib through inducing epithelial-mesenchymal transition (EMT). Notably, the current study revealed that sorafenib has no significant influence on the expression and secretion of TNF-α, and sorafenib had limited effectiveness on reversing EMT in HCC cells with high TNF-α expression. Inhibiting the expression of TNF-α with ulinastatin significantly enhanced the anti-tumor effect of sorafenib on HCC cells with high expression of TNF-α in vitro and in vivo., Interpretation: Our findings indicate that TNF-α may serve as a novel predictor of sorafenib sensitivity in HCC patients. Sorafenib combined with ulinastatin may improve the effectiveness of treatment of HCC in patients with high expression of TNF-α. FUND: This work was supported by grants from the National Natural Science Foundation of China (no.81572398; no.81672419), the Science and Technology Planning Project of Guangdong Province (no. 2017A010105003; no.2015A050502023; no.2016A020216010), and the Natural Science Foundation of Guangdong Province (no.2014A030313061; no. 2013B021800101)., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Sorafenib has been globally approved as the standard treatment for patients with advanced hepatocellular carcinoma (HCC). However, the response rate of HCC patients to sorafenib is limited because of tumor recurrence and metastasis. Therefore, seeking combined therapeutic strategies with sorafenib is necessary to improve the antitumor efficiency. Here we demonstrated that expression of MMP-2 is positively correlated with the migration ability of HCC cells. Cells with a higher MMP-2 expression (SK-HEP-1 cells) were less sensitive to sorafenib than those with lower MMP-2 expression (HepG2 cells). Cotreatment of cells with SB-3CT and sorafenib more strongly inhibited migration ability than with sorafenib treatment alone in both HCC cells with high and low expression of MMP-2. In vivo cell metastasis experiments confirmed the synergistic effects of sorafenib and SB-3CT in reducing lung metastasis of SK-HEP-1 cells. Mechanistically, we showed that the synergistic antitumor effect may be attributed to inhibition of the PI3K/AKT/mTOR signaling pathway, but not the RAF/MEK/ERK signaling pathway. With these results taken together, the current study demonstrates that inhibiting MMP-2 expression can enhance the antitumor effect of sorafenib in HCC cells with a high MMP-2 expression, which may provide a novel strategy to improve therapeutic efficiency in HCC.

Background: Liver re-resection plays a paramount role in treatment of patients with posthepatectomy hepatocellular carcinoma (HCC) recurrence. Laparoscopic liver resection has been a feasible alternative to open surgery. However, whether laparoscopic liver re-resection for posthepatectomy HCC recurrence is better than open liver re-resection remains unknown., Method: From January 2008 to December 2015, 30 patients with recurrent HCC after prior liver resection underwent laparoscopic liver re-resection in our center. To minimize any confounding factors, a propensity score matching study using a patient ratio of 1:1 was conducted to compare the short- and long-term outcomes of patients who underwent laparoscopic or open liver re-resection., Result: With the open surgery group compared laparoscopic group, operative time was 207.50 versus 200.5 min (p = 0.903), blood loss was 400 versus 100 ml (p = 0.000196), blood transfusion rate was 43.3 versus 0.0% (p = 0.000046), complication rates were 30.0 versus 6.7% (p = 0.01), and hospital stay was 13.5 versus 9.5 days (p = 0.000008). The median follow-up was 35 months. The 1-year, 3-year, 5-year disease-free survival rates were 79.0, 51.0, and 31.9%, versus 78.3, 57.4, and 43.0%, respectively (p = 0.474). The 1-year, 3-year, and 5-year overall survival rates were 89.4, 75, and 67.5%, versus 96.7, 85.0, and 74.4%, respectively (p = 0.413)., Conclusion: Laparoscopic liver re-resection for patients with posthepatectomy HCC recurrence provided comparable perioperative and oncological outcomes as open liver re-resection and can be a safe alternative to open procedure.

Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.