ARID1A Deficiency Is Associated With High Programmed Death Ligand 1 Expression in Hepatocellular Carcinoma

Differences in Tumor-Infiltrating Lymphocyte Counts in the Peritumoral Area in Patients Undergoing Hepatic Resection After Lenvatinib and Atezolizumab Plus Bevacizumab Therapy for Hepatocellular Carcinoma

AIM

With advances in systemic therapy, the number of patients with hepatocellular carcinoma (HCC) who can undergo hepatic resection has increased in recent years, but there are no reports evaluating the immune status in the peritumoral area.

METHODS

We enrolled 14 patients who underwent hepatic resection after lenvatinib (LEN, n = 7) or atezolizumab plus bevacizumab (ATZ/BEV, n = 5) therapy. Tumor-infiltrating lymphocytes (TILs), including CD3+ and CD8+ TILs, in the peritumoral area were evaluated by hematoxylin and eosin staining and immunohistochemistry.

RESULTS

The median TIL counts after LEN and ATZ/BEV therapy were 32 and 92 cells/0.237 mm2, respectively (p = 0.0044). The median CD3+ TIL counts after LEN and ATZ/BEV therapy were 26 and 71 cells/0.237 mm2, respectively (p = 0.0057). The median CD8+ TIL counts after LEN and ATZ/BEV therapy were 14 and 42 cells/0.237 mm2, respectively (p = 0.0044).

CONCLUSION

TIL counts, including those of CD3+ and CD8+ TILs, in the peritumoral area were significantly higher after ATZ/BEV than after LEN therapy.

Molecular and pathological landscape of the AT-rich interaction domain 1A (ARID1A) mutation in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths worldwide, with complex etiological factors and a diverse genetic landscape. Among the critical genetic mutations in HCC, the AT-rich interaction domain 1 A (ARID1A) gene, a key component of the SWI/SNF chromatin remodeling complex, stands out due to its significant role in both tumor suppression and oncogenesis. This review comprehensively examines the molecular and pathological impacts of ARID1A mutations in HCC. ARID1A mutations, which occur in approximately 7.9 % of HCC cases, predominantly involve truncating mutations leading to loss of function. These mutations are associated with various aggressive cancer features, including larger tumor size, higher rates of metastasis, and poor prognosis. The dual role of ARID1A in HCC is context-dependent, acting as a tumor suppressor by regulating cell cycle control, DNA damage repair, and gene expression, while also displaying oncogenic properties in specific contexts by promoting early tumorigenesis through oxidative stress pathways. Understanding the molecular mechanisms of ARID1A, including its interactions with key cellular pathways such as PI3K/AKT/mTOR, β-catenin, and PD-L1, provides insights into its complex role in HCC pathogenesis. Furthermore, ARID1A's impact on cancer stem cell maintenance, metabolic reprogramming, and immune evasion underscores its potential as a therapeutic target. This review highlights the need for context-specific therapeutic strategies targeting ARID1A, which could lead to more effective treatments for HCC, addressing both its tumor-suppressive and oncogenic activities.

Chromatin Remodelers Are Regulators of the Tumor Immune Microenvironment

Immune checkpoint inhibitors show remarkable responses in a wide range of cancers, yet patients develop adaptive resistance. This necessitates the identification of alternate therapies that synergize with immunotherapies. Epigenetic modifiers are potent mediators of tumor-intrinsic mechanisms and have been shown to regulate immune response genes, making them prime targets for therapeutic combinations with immune checkpoint inhibitors. Some success has been observed in early clinical studies that combined immunotherapy with agents targeting DNA methylation and histone modification; however, less is known about chromatin remodeler-targeted therapies. Here, we provide a discussion on the regulation of tumor immunogenicity by the chromatin remodeling SWI/SNF complex through multiple mechanisms associated with immunotherapy response that broadly include IFN signaling, DNA damage, mismatch repair, regulation of oncogenic programs, and polycomb-repressive complex antagonism. Context-dependent targeting of SWI/SNF subunits can elicit opportunities for synthetic lethality and reduce T-cell exhaustion. In summary, alongside the significance of SWI/SNF subunits in predicting immunotherapy outcomes, their ability to modulate the tumor immune landscape offers opportunities for therapeutic intervention.

The current status and future of PD-L1 in liver cancer

The application of immunotherapy in tumor, especially immune checkpoint inhibitors (ICIs), has played an important role in the treatment of advanced unresectable liver cancer. However, the efficacy of ICIs varies greatly among different patients, which has aroused people's attention to the regulatory mechanism of programmed death ligand-1 (PD-L1) in the immune escape of liver cancer. PD-L1 is regulated by multiple levels and signaling pathways in hepatocellular carcinoma (HCC), including gene variation, epigenetic inheritance, transcriptional regulation, post-transcriptional regulation, and post-translational modification. More studies have also found that the high expression of PD-L1 may be the main factor affecting the immunotherapy of liver cancer. However, what is the difference of PD-L1 expressed by different types of cells in the microenvironment of HCC, and which type of cells expressed PD-L1 determines the effect of tumor immunotherapy remains unclear. Therefore, clarifying the regulatory mechanism of PD-L1 in liver cancer can provide more basis for liver cancer immunotherapy and combined immune treatment strategy. In addition to its well-known role in immune regulation, PD-L1 also plays a role in regulating cancer cell proliferation and promoting drug resistance of tumor cells, which will be reviewed in this paper. In addition, we also summarized the natural products and drugs that regulated the expression of PD-L1 in HCC.

Left Renal Vein Division during Open Surgical Repair for Abdominal Aortic Aneurysm May Cause Long-Term Kidney Remodeling

BACKGROUND

Left renal vein division (LRVD) is a maneuver performed during open surgical repair for abdominal aortic aneurysms. Even so, the long-term effects of LRVD on renal remodeling are unknown. Therefore, we hypothesized that interrupting the venous return of the left renal vein might cause renal congestion and fibrotic remodeling of the left kidney.

METHODS

We used a murine left renal vein ligation model with 8-week-old to 12-week-old wild-type male mice. Bilateral kidneys and blood samples were harvested postoperatively on days 1, 3, 7, and 14. We assessed the renal function and the pathohistological changes in the left kidneys. In addition, we retrospectively analyzed 174 patients with open surgical repairs between 2006 and 2015 to assess the influence of LRVD on clinical data.

RESULTS

Temporary renal decline with left kidney swelling occurred in a murine left renal vein ligation model. In the pathohistological assessment of the left kidney, macrophage accumulation, necrotic atrophy, and renal fibrosis were observed. In addition, Myofibroblast-like macrophage, which is involved in renal fibrosis, was observed in the left kidney. We also noted that LRVD was associated with temporary renal decline and left kidney swelling. LRVD did not, however, impair renal function in long-term observation. Additionally, the relative cortical thickness of the left kidney in the LRVD group was significantly lower than that of the right kidney. These findings indicated that LRVD was associated with left kidney remodeling.

CONCLUSIONS

Venous return interruption of the left renal vein is associated with left kidney remodeling. Furthermore, interruption in the venous return of the left renal vein does not correlate with chronic renal failure. Therefore, we suggest careful follow-up of renal function after LRVD.

Textbook outcome in the laparoscopic cholecystectomy of acute cholecystitis

PURPOSE

Textbook outcome (TO) is a novel composite measure of clinical outcomes that can be used to measure the quality of surgical outcomes. The aim of this cohort study was to propose TO criteria for laparoscopic cholecystectomy for acute cholecystitis and to identify reasons for TO failure and individual patient factors that predispose to failure.

METHODS

We retrospectively analyzed data for 189 patients with acute cholecystitis who underwent laparoscopic cholecystectomy. TO was defined as laparoscopic cholecystectomy without conversion to open cholecystectomy, intraoperative complications, postoperative complications (Clavien-Dindo classification ≥2), prolonged length of stay (≥10 days), readmission within 30 days, or mortality.

RESULTS

TO was achieved in 154 of 189 patients who underwent laparoscopic cholecystectomy for acute cholecystitis. Medical costs were lower in the TO-achieved group than in the TO-failure group. Factors associated with TO failure on multivariate analysis were age > 70 years, hemoglobin <11.9 g/dL, and white blood cells >18 000 / μL (all P < .05).

CONCLUSIONS

Applying TO to patients with acute cholecystitis allowed us to evaluate the overall quality of care related to hospitalization. TO may provide better assessment of the quality of care and help determine the treatment choice and reduce costs.

Radiomics models based on multisequence MRI for predicting PD-1/PD-L1 expression in hepatocellular carcinoma

The purpose of this study was to explore the effectiveness of radiomics based on multisequence MRI in predicting the expression of PD-1/PD-L1 in hepatocellular carcinoma (HCC). One hundred and eight patients with HCC who underwent contrast-enhanced MRI 2 weeks before surgical resection were enrolled in this retrospective study. Corresponding paraffin sections were collected for immunohistochemistry to detect the expression of PD-1 and PD-L1. All patients were randomly divided into a training cohort and a validation cohort at a ratio of 7:3. Univariate and multivariate analyses were used to select potential clinical characteristics related to PD-1 and PD-L1 expression. Radiomics features were extracted from the axial fat-suppression T2-weighted imaging (FS-T2WI) images and the arterial phase and portal venous phase images from the axial dynamic contrast-enhanced MRI, and the corresponding feature sets were generated. The least absolute shrinkage and selection operator (LASSO) was used to select the optimal radiomics features for analysis. Logistic regression analysis was performed to construct single-sequence and multisequence radiomics and radiomic-clinical models. The predictive performance was judged by the area under the receiver operating characteristic curve (AUC) in the training and validation cohorts. In the whole cohort, PD-1 expression was positive in 43 patients, and PD-L1 expression was positive in 34 patients. The presence of satellite nodules served as an independent predictor of PD-L1 expression. The AUC values of the FS-T2WI, arterial phase, portal venous phase and multisequence models in predicting the expression of PD-1 were 0.696, 0.843, 0.863, and 0.946 in the training group and 0.669, 0.792, 0.800 and 0.815 in the validation group, respectively. The AUC values of the FS-T2WI, arterial phase, portal venous phase, multisequence and radiomic-clinical models in predicting PD-L1 expression were 0.731, 0.800, 0.800, 0.831 and 0.898 in the training group and 0.621, 0.743, 0.771, 0.810 and 0.779 in the validation group, respectively. The combined models showed better predictive performance. The results of this study suggest that a radiomics model based on multisequence MRI has the potential to predict the preoperative expression of PD-1 and PD-L1 in HCC, which could become an imaging biomarker for immune checkpoint inhibitor (ICI)-based treatment.

The somatic mutational landscape and role of the ARID1A gene in hepatocellular carcinoma

Introduction

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours worldwide. Clarification of the somatic mutational landscape of important genes could reveal new therapeutic targets and facilitate individualized therapeutic approaches for HCC patients. The mutation and expression changes in the ARID1A gene in HCC remain controversial.

Methods

First, cBioPortal was used to visualize genetic alterations and DNA copy number alterations (CNAs) in ARID1A. The relationships between ARID1A mutation status and HCC patient clinicopathological features and overall survival (OS) were also determined. Then, a meta-analysis was performed to evaluate the effect of ARID1A mutation or expression on the prognosis of HCC patients. Finally, the role of ARID1A in HCC progression was verified by in vitro experiments.

Results

ARID1A mutation was detected in 9.35% (33/353) of sequenced HCC cases, and ARID1A mutation decreased ARID1A mRNA expression. Patients with ARID1A alterations presented worse OS than those without ARID1A alterations. Meta-analysis and human HCC tissue microarray (TMA) analysis revealed that HCC patients with low ARID1A expression had worse OS and relapse-free survival (RFS), and low ARID1A expression was negatively correlated with tumour size. Then, ARID1A gain-of-function and loss-of-function experiments demonstrated the tumour suppressor role of ARID1A in HCC in vitro. In terms of the mechanism, we found that ARID1A could inhibit HCC progression by regulating retinoblastoma-like 1 (RBL1) expression via the JNK/FOXO3 pathway.

Conclusions

ARID1A can be considered a potential prognostic biomarker and candidate therapeutic target for HCC.

Clinical Significance of Signal Regulatory Protein Alpha (SIRPα) Expression in Hepatocellular Carcinoma

BACKGROUND

Signal regulatory protein alpha (SIRPα), expressed in the macrophage membrane, inhibits phagocytosis of tumor cells via CD47/SIRPα interaction, which acts as an immune checkpoint factor in cancers. This study aimed to clarify the clinical significance of SIRPα expression in hepatocellular carcinoma (HCC).

METHODS

This study analyzed SIRPα expression using RNA sequencing data of 372 HCC tissues from The Cancer Genome Atlas (TCGA) and immunohistochemical staining of our 189 HCC patient cohort. The correlation between SIRPα expression and clinicopathologic factors, patient survival, and intratumor infiltration of immune cells was investigated.

RESULTS

Overall survival (OS) was significantly poorer with high SIRPα expression than with low expression in both TCGA and our cohort. High SIRPα expression correlated with lower recurrence-free survival (RFS) in our cohort. High SIRPα expression was associated with higher rates of microvascular invasion and lower serum albumin levels and correlated with greater intratumor infiltration of CD68-positive macrophages and myeloid-derived suppressor cells (MDSCs). Multivariate analysis showed that SIRPα expression and high infiltration of CD8-positive T cells and MDSCs were predictive factors for both RFS and OS. Patients with high SIRPα expression and infiltration of CD8-positive T cells and MDSCs had significantly lower RFS and OS rates. In spatial transcriptomics sequencing, SIRPα expression was significantly correlated with CD163 expression.

CONCLUSIONS

High SIRPα expression in HCC indicates poor prognosis, possibly by inhibiting macrophage phagocytosis of tumor cells, promoting MDSC infiltration and inducing antitumor immunity. Treatment alternatives using SIRPα blockage should be considered in HCC as inhibiting macrophage antitumor immunity and MDSCs.

Inhibition of Arid1a increases stem/progenitor cell-like properties of liver cancer

ARID1A, a key subunit of the SWI/SNF chromatin remodeling complex, exhibits recurrent mutations in various types of human cancers, including liver cancer. However, the function of ARID1A in the pathogenesis of liver cancer remains controversial. Here, we demonstrate that Arid1a knockout may result in states of different cell differentiation, as indicated by single-cell RNA sequencing (scRNA-seq) analysis. Bulk RNA-seq also revealed that Arid1a deficiency upregulated these genes related to cell stemness and differentiation, but downregulated genes related to the hepatic functions. Furthermore, we confirmed that deficiency of Arid1a increased the expression of hepatic stem/progenitor cell markers, such as Cd133 and Epcam, and enhanced the self-renewal ability of cells. Mechanistic studies revealed that Arid1a loss remodeled the chromatin accessibility of some genes related to liver functions. Thus, Arid1a deficiency might contribute to cancer development by increasing the number of stem/progenitor-like cells through dysregulating the expression of these genes related to cell stemness, differentiation and liver functions.

Treating ARID1A mutated cancers by harnessing synthetic lethality and DNA damage response

Chromatin remodeling is an essential cellular process for organizing chromatin structure into either open or close configuration at specific chromatin locations by orchestrating and modifying histone complexes. This task is responsible for fundamental cell physiology including transcription, DNA replication, methylation, and damage repair. Aberrations in this activity have emerged as epigenomic mechanisms in cancer development that increase tumor clonal fitness and adaptability amidst various selection pressures. Inactivating mutations in AT-rich interaction domain 1A (ARID1A), a gene encoding a large nuclear protein member belonging to the SWI/SNF chromatin remodeling complex, result in its loss of expression. ARID1A is the most commonly mutated chromatin remodeler gene, exhibiting the highest mutation frequency in endometrium-related uterine and ovarian carcinomas. As a tumor suppressor gene, ARID1A is essential for regulating cell cycle, facilitating DNA damage repair, and controlling expression of genes that are essential for maintaining cellular differentiation and homeostasis in non-transformed cells. Thus, ARID1A deficiency due to somatic mutations propels tumor progression and dissemination. The recent success of PARP inhibitors in treating homologous recombination DNA repair-deficient tumors has engendered keen interest in developing synthetic lethality-based therapeutic strategies for ARID1A-mutated neoplasms. In this review, we summarize recent advances in understanding the biology of ARID1A in cancer development, with special emphasis on its roles in DNA damage repair. We also discuss strategies to harness synthetic lethal mechanisms for future therapeutics against ARID1A-mutated cancers.

Effect of CRISPR Knockout of AXIN1 or ARID1A on Proliferation and Migration of Porcine Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is an aggressive disease lacking effective treatment. Animal models of HCC are necessary for preclinical evaluation of the safety and efficacy of novel therapeutics. Large animal models of HCC allow testing image-guided locoregional therapies, which are widely used in the management of HCC. Models with precise tumor mutations mimicking human HCC provide valuable tools for testing precision medicine. AXIN1 and ARID1A are two of the most frequently mutated genes in human HCC. Here, we investigated the effects of knockout of AXIN1 and/or ARID1A on proliferation, migration, and chemotherapeutic susceptibility of porcine HCC cells and we developed subcutaneous tumors harboring these mutations in pigs. Gene knockout was achieved by CRISPR/Cas9 and was validated by Next Generation Sequencing. AXIN1 knockout increased the migration of porcine HCC cells but did not alter the cell proliferation. Knockout of ARID1A increased both the proliferation and migration of porcine HCC cells. Simultaneous knockout of AXIN1 and ARID1A increased the migration, but did not alter the proliferation of porcine HCC cells. The effect of gene knockout on the response of porcine HCC cells to two of the most commonly used systemic and locoregional HCC treatments was investigated; sorafenib and doxorubicin, respectively. Knockout of AXIN1 and/or ARID1A did not alter the susceptibility of porcine HCC cells to sorafenib or doxorubicin. Autologous injection of CRISPR edited HCC cells resulted in development of subcutaneous tumors in pigs, which harbored the anticipated edits in AXIN1 and/or ARID1A. This study elucidates the effects of CRISPR-mediated knockout of HCC-associated genes in porcine HCC cells, and lays the foundation for development and utilization of genetically-tailored porcine HCC models for in vivo testing of novel therapeutic approaches in a clinically-relevant large animal model.

ARID1A expression in hepatocellular carcinoma and relation to tumor recurrence after microwave ablation

Aim of the study

AT-rich interactive domain 1A (ARID1A) is a subunit of the switch/sucrose non-fermentable chromatin remodeling complex, which is commonly mutated in human cancers. The clinical and pathological significance of ARID1A alteration in hepatocellular carcinoma (HCC) has not yet been clarified. The present study aimed to evaluate the clinical significance of the ARID1A gene signature in HCC and its relation to the likelihood of tumor recurrence after microwave ablation (MWA).

Material and methods

This study included 50 patients with cirrhotic HCC of Barcelona Clinic Liver Cancer stages 0/A eligible for MWA. Tumor and peri-tumor biopsies were obtained just prior to MWA and assessed for tumor pathological grade and ARID1A expression by immunohistochemistry. Patients were followed for one year after complete tumor ablation to detect any recurrence.

Results

Tumor size (^MCp = 0.010) and α-fetoprotein level (p = 0.013) can effectively predict the response to MWA. Nuclear expression of ARID1A was significantly lower in HCC compared to the corresponding peri-tumor cirrhotic liver tissues (p = 0.002), but no significant difference in ARID1A cytoplasmic expression was found. Nuclear ARID1A expression level in HCC showed a significantly negative relation to tumor size (^MCp = 0.006), pathological grade (^MCp = 0.046) and post-MWA tumor recurrence (^FEp = 0.041).

Conclusions

ARID1A loss may enhance HCC aggressiveness and post-MWA tumor recurrence. ARID1A could be a potential target to select HCC patients for future therapies.

ARID1A Downregulation Predicts High PD-L1 Expression and Worse Clinical Outcome in Patients With Gallbladder Cancer

BACKGROUND

Recent studies have confirmed that AT-rich interactive domain-containing protein 1A (ARID1A) plays a critical role in tumorigenesis, but its role in gallbladder cancer (GBC) remains unclear.

METHODS

In total, 224 patients from Zhongshan Hospital were recruited for this retrospective study. The clinicopathological and baseline characteristics of the patients were collected. Bioinformatics analysis was performed to reveal variations in genes and signaling pathways, and ARID1A and PD-L1 expression and the number of PD1+ tumor-infiltrating lymphocytes (TILs) were measured by immunohistochemical staining.

RESULTS

ARID1A expression was negatively correlated with overall survival in patients with GBC, and multivariate analysis identified ARID1A as an independent prognostic factor for overall survival. A heatmap and gene set enrichment analysis suggested that cytotoxic T lymphocyte signatures and immune-related signaling pathways were downregulated in ARID1A low tumors. Subsequent immunohistochemical staining confirmed that ARID1A expression was negatively correlated with PD-L1 expression and PD1+ TILs in the tumor microenvironment. The Kaplan-Meier analysis suggested that high ARID1A expression combined with low PD-L1 expression or low PD1+ TIL counts is associated with the best prognosis in patients with GBC.

CONCLUSION

ARID1A inactivation can lead to a worse prognosis in patients with GBC, potentially by mediating immune evasion through the PD1/PD-L1 pathway.

Myeloid‑derived suppressor cell infiltration is associated with a poor prognosis in patients with hepatocellular carcinoma

The clinicopathological features of myeloid-derived suppressor cell (MDSC) and CD8⁺ T-cell infiltration in hepatocellular carcinoma (HCC) are poorly understood. The present study examined MDSC and CD8⁺ T-cell infiltration in surgically resected primary HCC specimens and investigated the association of MDSC and CD8⁺ T-cell infiltration with clinicopathological features and patient outcomes. Using a database of 466 patients who underwent hepatic resection for HCC, immunohistochemical staining of CD33 (an MDSC marker) and CD8 was performed. High infiltration of MDSCs within the tumor was observed in patients with a poorer Barcelona Clinic Liver Cancer stage, larger tumor size, more poorly differentiated HCC, and greater presence of portal venous thrombosis, microscopic vascular thrombosis and macroscopic intrahepatic metastasis. MDSC infiltration and CD8⁺ T-cell infiltration were independent predictors of recurrence-free survival and overall survival, respectively. Stratification based on the MDSC and CD8⁺ T-cell status of the tumors was also associated with recurrence-free survival (10 year-recurrence-free survival; MDSC^highCD8⁺ T-cell^Low, 3.68%; others, 25.7%) and overall survival (10 year-overall survival; MDSC^highCD8⁺ T-cell^Low, 12.0%; others, 56.7%). In conclusion, the present large cohort study revealed that high MDSC infiltration was associated with a poor clinical outcome in patients with HCC. Furthermore, the combination of the MDSC and tumor-infiltrating CD8⁺ T-cell status enabled further classification of patients based on their outcomes.

Lymphocyte-to-C-reactive protein ratio as a prognostic factor for hepatocellular carcinoma

BACKGROUND

Systemic inflammation has been correlated with worse survival for some cancers. We evaluated prognostic values of various inflammatory factor combinations in patients who underwent resections for hepatocellular carcinoma (HCC).

METHODS

We retrospectively analysed 306 consecutive patients with HCC who underwent curative liver resections. After assessing eight combinations of inflammatory markers for predictive value for recurrence, we focused on lymphocyte-to-C-reactive protein ratio (LCR) to elucidate its associations with recurrence-free survival (RFS) and overall survival (OS) in univariate and multivariate analyses (Cox proportional hazards model). We also used immunohistochemical CD34 and CD8 staining to investigate the mechanism of LCR elevation.

RESULTS

LCR showed the highest association with RFS in HCC patients among the compared indices. High preoperative LCR correlated with a high serum albumin concentration, small tumour size, early Barcelona Clinic Liver Cancer stage and low rates of microscopic vascular invasion and microscopic intrahepatic metastasis. Higher preoperative LCR was an independent predictor of longer RFS and OS in this cohort. High LCR patients had fewer vessels encapsulating tumour clusters, and higher intratumoural CD8⁺ T-cell counts than low LCR patients.

CONCLUSIONS

Preoperative LCR is a novel and convenient prognostic marker for patients with HCC, and is associated with the tumour microenvironment immune status.