Hepatocellular Carcinoma Lines Research Articles

Skin-Resident γδ T Cells Mediate Potent and Selective Antitumor Cytotoxicity through Directed Chemotactic Migration and Mobilization of Cytotoxic Granules

Dendritic epidermal T cells (DETCs) are a unique subset of γδ T cells that reside predominantly in mouse epidermis, yet their antitumor functions remain enigmatic. Here we report that DETCs mediate potent and exquisitely selective cytotoxicity against diverse tumor types while sparing healthy cells. In vitro, DETCs induced apoptosis in melanoma, hepatoma, colon carcinoma and lymphoma lines in a dose- and time-dependent manner that required direct cell-cell contact. In vivo, adoptive DETC transfer significantly suppressed melanoma growth and metastasis while prolonging survival. Mechanistically, DETCs upregulated perforin/granzyme B expression upon tumor recognition, and inhibition of this pathway ablated cytotoxicity. DETCs selectively homed to and formed intimate contacts with tumor cells in vivo through directed chemotaxis and aggregation. Tumor engagement triggered pro-inflammatory DETC activation while dampening immunosuppressive factors in the microenvironment. Notably, mTOR signaling coupled tumor recognition to DETC trafficking, cytotoxicity and inflammatory programs, as rapamycin treatment impaired effector functions and therapeutic efficacy. Collectively, these findings establish DETCs as multidimensional antitumor effectors and provide insights for harnessing their unique biology for cancer immunotherapy.

Abstract C112: Hemp extract attenuates the proliferation of hepatocellular carcinoma cells- derive cells from racially diverse populations by inhibiting the Interferone-1 signaling pathway

Abstract Hepatocellular Carcinoma (HCC) is a highly fatal disease where race/ethnicity plays a vital role in determining incidence, mortality, and survival rates. The incidence of HCC is highest in Asia and Africa. Furthermore, there is a statistically significant increase in incidence and mortality and a decrease in 5-year survival rates in African American (AA)/Black patients compared to non-Hispanic white patients. The HCC patients might benefit from a holistic dietary approach, including hemp extract, along with their clinical treatment. Our bioinformatics analysis of The Cancer Genome Atlas (TCGA) identified the IFN-I signaling genes (ISGs) as the most significantly enriched pathway in AA/Black HCC patients. Consistent with this finding, RNA-seq analysis of archived HCC tumors from white (n=14) and AA/Black (n=18) patients further confirmed the upregulation of ISGs in these cohorts. Due to the severe toxicity of the currently available cancer treatments, there is also a demand for the development of alternative therapies with high efficacy and low side effects. We characterized 16 varieties of hemp for their polyphenols, antioxidation, CBDs, and terpenes contents and determined the effects of hemp extracts on the proliferation of HepG2 (white patients), Hep3B, and O/20 (Black patients), and HuH-7 (Asian Patient) HCC cell lines. Among different hemp varieties, KY-Plume extract showed the highest concentration of polyphenols, antioxidation activity, CBDA, and terpenes. It also most potently inhibited the growth of all HCC cell lines (IC50s 20-25 mg/ml), irrespective of their racial origin. Hemp treatment reduced the phosphorylation of the IFN downstream mediators, Jak-1, Tyk2, STAT1, and STAT2, in all HCC cell lines. In addition, hemp treatment also inhibited phosphorylation/activation of PI3K-Akt-mTOR and MAPK pathways. Currently, research is underway to identify the active chemical agent in hemp and test it on other patient-derived HCC lines and in an in vivo model. In conclusion, our data suggest that hemp can attenuate HCC proliferation by inhibiting multiple cellular signaling pathways, including the IFN-1 pathway. Our data suggest that HCC patients might benefit from a holistic dietary approach, including hemp extract, along with their clinical treatment. (Funded: Even-Allen-USDA and P20 CA264068-01-NIH). Citation Format: Rafat A Siddiqui, Haiwen Li, Ramesh Dhakal, Milton O Faison, Devanand Sarkar.. Hemp extract attenuates the proliferation of hepatocellular carcinoma cells- derive cells from racially diverse populations by inhibiting the Interferone-1 signaling pathway [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C112.

Knockdown of SLC16A3 decreases extracellular lactate concentration in hepatocellular carcinoma, alleviates hypoxia and induces ferroptosis

SLC16A3/monocarboxylate transporter 4 (MCT4) regulates intracellular lactate transport and is highly expressed in many tumors, indicating poor prognosis. It may be related to inducing hypoxia, apoptosis and other mechanisms, but the study of MCT4 in HCC is far from complete. In this study, we first analyzed the expression of SLC16A3 in HCC tumor and non-tumor tissue samples based on TCGA data and immunohistochemistry. Subsequently, the effects of SLC16A3 expression on cell proliferation and invasion were analyzed using hepatocellular carcinoma (HCC) lines, and Western blot (WB) analysis was performed to explore the changes in pathway proteins and ferroptosis proteins. Finally, the drug sensitivity was tested by CCK8 kit. We found that SLC16A3 was significantly upregulated in tumor tissues, and was significantly correlated with TNM stage, histological grade, and macrovascular invasion. TCGA data and WB analysis showed that the high expression of SLC16A3 induced hypoxia, and knockdown could reverse hypoxia and inhibit ERK phosphorylation, thus limiting the malignant behavior of HCC cells. Moreover, knockdown of SLC16A3 significantly increased the level of lipid peroxidation and reactive oxygen species (ROS), while the expressions of GPX4, DHODH and SLC7A11 were inhibited. The expression of SLC16A3 affected the sensitivity of HCC cells to chemotherapy and targeted drugs, and RNA sequencing data suggested that the expression level influenced tumor microenvironment and response to immunotherapy. So, we draw a conclude that SLC16A3 is associated with poor prognosis of HCC. Inhibition of SLC16A3 expression is a potential therapeutic target for HCC.

Study on antihepatocellular carcinoma effect of 6-shogaol and curcumin through network-based pharmacological and cellular assay.

Hepatocellular carcinoma currently has the third highest mortality rate in the world. Patients with hepatocellular carcinoma are on the rise and at a younger age, but research into the pharmacological effects of cancer is mostly single-component, and natural plant products can have additive or synergistic effects that can better amplify the effects of intervention in cancer. To evaluate the synergistic therapeutic effects of 6-shogaol and curcumin against hepatocellular carcinoma line HepG2 cells. In this study, a network pharmacology approach was used to predict and validate the mol ecular targets and pathways of the hepatocellular carcinoma (HCC) of 6-shogaol and curcumin in combination and to investigate their mechanism of action. The results were also validated by cellular assays. HepG2 cells were treated with 6-shogaol and curcumin as well as the combination of the two. The combination index of 6-shogaol and curcumin in HepG2 cells was calculated using Compusyn software according to the Chou-Talalay equation. The synergistic anti-cancer effect was next investigated by MTT assay, apoptosis assay and cell cycle assay. The combined anti-hepatocellular carcinoma effect of the Ras-mediated PI3K/AKT and MAPK signalling pathways was analysed using protein blotting assays. A network pharmacology-based screening identified 72 core targets of 6-curcumin and curcumin in hepatocellular carcinoma, and predicted that the main signalling pathway is the Ras signalling pathway. The anti-cancer effects of 6-shogaol and curcumin were validated in cell-based assays and the optimal synergistic concentrations of 5μmoL/L for 6-shogaol and 30μmoL/L for curcumin were determined. 6-shogaol and curcumin synergistically blocked the cell cycle in the G2/M phase and promoted apoptosis. Immunoblot analysis confirmed for the first time the combined action of both in down-regulating the Ras-mediated PI3K/AKT and MAPK signaling pathways. In addition, 6-shogaol and curcumin acting together downregulated Cyclin-B, CDK-1, Bcl-2, and upregulated BAX. 6-shogaol and curcumin act synergistically to alter the morphology of hepatocellular carcinoma cells, block the cell cycle in the G2/M phase, inhibit proliferation and division, and effectively promote late apoptosis. The combined action of these two components provides a theoretical basis for the further development of novel anti-liver cancer products.

Variaciones <i>in vitro</i> de la actividad metabólica de los macrófagos frente acélulas tumorales de cáncer de pulmón y hepatocarcinoma

Introduction. Metabolic activity determines the phenotype of macrophages, which can be oriented towards activation of defense mechanisms or tissue repair (phenotypic plasticity). Objectives. To evaluate the behavior of the main enzymes involved in the metabolic pathways of energy production in macrophages exposed to two tumor environments. Methods. In vitro experimental study that consisted of measuring the enzymatic activity of hexokinase (HQN), lactate dehydrogenase (LDH), isocitrate dehydrogenase (IDH) and glucose-6-phosphate dehydrogenase (G6P) by spectrophotometric absorbance in macrophages exposed to lung cancer and hepatocarcinoma cells. We compared the medians of enzyme activity between the isolated cell lines and their co-cultures (Kruskal-Wallis (H) test) and the medians of enzyme activity between each co-culture (Mann-Whitney U test). Results. The enzymatic activity of LDH was significantly higher in macrophages exposed to the hepatocellular carcinoma line, at 0 (H = 5,96, p = 0,03), 2 (H = 6,49, p = 0,01) and 6 hours (H = 7,20, p = 0,004). On the contrary, the enzymatic activity of IDH and HQN in cocultures was significantly lower compared to monocultures. The G6P had lower activity after 2 hours in macrophage monocultures compared to cocultures in the hepatocellular carcinoma line. The enzymatic activity of LDH, IDH, G6P and HQN in macrophages exposed to lung cancer cells was lower compared to macrophages and tumor cells in monoculture. Conclusion: The interaction between macrophages and tumor cells produces changes in the ways glucose is used.

A novel metabolism-related gene signature in patients with hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) remains a global challenge as it is the sixth most common neoplasm worldwide and the third leading cause of cancer-related death. A key feature of HCC is abnormal metabolism, which promotes cancer cell proliferation, survival, invasion, and metastasis. However, the significance of metabolism-related genes (MRGs) in HCC remains to be elucidated. Here, we aim to establish a novel metabolism-related prognostic signature for the prediction of patient outcomes and to investigate the value of MRG expression in the prognostic prediction of HCC. In our research, a Metabolism-Related Risk Score (MRRS) model was constructed using 14 MRGs (DLAT, SEPHS1, ACADS, UCK2, GOT2, ADH4, LDHA, ME1, TXNRD1, B4GALT2, AK2, PTDSS2, CSAD, and AMD1). The Kaplan-Meier curve confirmed that the MRRS has a high accuracy in predicting the prognosis of HCC patients (p<0.001). According to the MRRS model, the area under the curve (AUC) values for predicting the prognosis of patients with hepatocellular carcinoma at 1, 3, and 5 years reached 0.829, 0.760, and 0.739, respectively. Functional analyses revealed that signaling pathways associated with the cell cycle were largely enriched by differential genes between high and low-risk groups. In addition, dendritic cells (DCs) (p<0.001), CD4+ T cells (p<0.01), CD8+ T cells (p<0.001), B cells (p<0.001), neutrophils (p<0.001), macrophages (p<0.001) had a higher proportion of infiltrates in high-risk populations. Low GOT2 expression is associated with poor prognosis in patients with hepatocellular carcinoma. Knockdown of GOT2 significantly increased the migration capacity of the Huh7 and MHCC97H hepatocellular carcinoma lines. Our research reveals that GOT2 is negatively related to the survival of patients with hepatocellular carcinoma and GOT2 may contribute to tumor progression by inhibiting the ability of tumor cells to migrate.

Phase II study on safety and efficacy of NMS-01940153E, an MPS1 inhibitor with first-in-class potential, in adult patients with unresectable hepatocellular carcinoma (HCC) previously treated with systemic therapy.

TPS4185 Background: Monopolar Spindle 1 (MPS1) kinase regulates the spindle assembly checkpoint (SAC) which ensures proper division of chromosomes during mitosis. MPS1 is overexpressed in several tumors, including hepatocellular carcinoma (HCC), where it correlates with tumor features and poor overall and disease-free survival. NMS-01940153E is a novel, highly potent and selective small molecule inhibitor of MPS1 kinase with long residence time and strong preclinical anti-tumor activity in different tumor types. In HCC lines, specifically, NMS-01940153E showed ~2-Log higher anti-proliferative activity compared to sorafenib, lenvatinib, and regorafenib. In a previous open-label first-in-human (FIH) study, CL1-81694-001 (EudraCT 2014-002023-10), signs of activity in HCC were detected. Recently, the treatment paradigm for advanced HCC has changed, with immunotherapy combinations in first line and TKIs shifted in later lines. However, the overall prognosis of patients with advanced HCC remains poor, and there is a strong need of new drugs in this setting. NMS-01940153E novel mechanism of action, inhibiting the SAC and interfering with genomic stability in HCC, may offer a new therapeutic option in HCC. Based on the promising FIH results, a Phase I/II study, MPSA-153-001 (EudraCT 2020-001002-26), was initiated in patients with HCC previously treated with more than one systemic therapy. Methods: The Phase II part of the MPSA-293-001 trial is designed as a two-stage study with an interim analysis for futility and safety rules for unacceptable toxicity. The primary objective is to assess the antitumor activity of NMS-01940153E in adult patients with unresectable HCC previously treated with systemic therapy measured as objective response rate (ORR) by investigator-assessed RECIST 1.1. Secondary endpoints are safety, PK, ORR as measured by investigator-assessed mRECIST, DoR, PFS and OS. Exploratory endpoints include biomarkers. NMS-01940153E is administered IV, on days 1, 8 and 15 every 4 weeks at the RP2D of 100 mg/m2/wk, which showed PK in a predicted active range. Key eligibility criteria are 1) diagnosis of HCC; 2) disease progression on standard-of-care treatment including an immune checkpoint inhibitor as first line and at least one TKI; 3) no more than 3 prior systemic treatment lines. Interim evaluation for futility will be undertaken as soon as the first 10 evaluable patients will be enrolled. If at least 1 responder is observed with no safety issues, enrollment will proceed up to 38 evaluable patients. Otherwise, the study will be terminated for futility. An independent DSMB will review the interim results and provide recommendation on the study progress. Recruitment is currently ongoing in Italy and Spain and an FDA “Study May Proceed Notification” was received in January 2023. Clinical trial information: NCT05630937 .

Epigenetic reactivation of tumor suppressor genes with CRISPRa technologies as precision therapy for hepatocellular carcinoma

BackgroundEpigenetic silencing of tumor suppressor genes (TSGs) is a key feature of oncogenesis in hepatocellular carcinoma (HCC). Liver-targeted delivery of CRISPR-activation (CRISPRa) systems makes it possible to exploit chromatin plasticity, by reprogramming transcriptional dysregulation.ResultsUsing The Cancer Genome Atlas HCC data, we identify 12 putative TSGs with negative associations between promoter DNA methylation and transcript abundance, with limited genetic alterations. All HCC samples harbor at least one silenced TSG, suggesting that combining a specific panel of genomic targets could maximize efficacy, and potentially improve outcomes as a personalized treatment strategy for HCC patients. Unlike epigenetic modifying drugs lacking locus selectivity, CRISPRa systems enable potent and precise reactivation of at least 4 TSGs tailored to representative HCC lines. Concerted reactivation of HHIP, MT1M, PZP, and TTC36 in Hep3B cells inhibits multiple facets of HCC pathogenesis, such as cell viability, proliferation, and migration.ConclusionsBy combining multiple effector domains, we demonstrate the utility of a CRISPRa toolbox of epigenetic effectors and gRNAs for patient-specific treatment of aggressive HCC.

Identification of TIAM1 as a Potential Synthetic-Lethal-like Gene in a Defined Subset of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC), the most common type of liver cancer, has very poor outcomes. Current therapies often have low efficacy and significant toxicities. Thus, there is a critical need for the development of novel therapeutic approaches for HCC. We have developed a novel bioinformatics pipeline, which integrates genome-wide DNA methylation and gene expression data, to identify genes required for the survival of specific molecular cancer subgroups but not normal cells. Targeting these genes may induce cancer-specific "synthetic lethality". Initially, five potential HCC molecular subgroups were identified based on global DNA methylation patterns. Subgroup-2 exhibited the most unique methylation profile and two candidate subtype-specific vulnerability or SL-like genes were identified for this subgroup, including TIAM1, a guanine nucleotide exchange factor encoding gene known to activate Rac1 signalling. siRNA targeting TIAM1 inhibited cell proliferation in TIAM1-positive (subgroup-2) HCC cell lines but had no effect on the normal hepatocyte HHL5 cell line. Furthermore, TIAM1-positive/subgroup-2 cell lines were significantly more sensitive to the TIAM1/RAC1 inhibitor NSC23766 compared with TIAM1-negative HCC lines or the normal HHL5 cell line. The results are consistent with a synthetic lethal role for TIAM1 in a methylation-defined HCC subgroup and suggest it may be a viable therapeutic target in this subset of HCC patients.

EIF4A1 Is a Prognostic Marker and Actionable Target in Human Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a primary liver tumor with high lethality and increasing incidence worldwide. While tumor resection or liver transplantation is effective in the early stages of the disease, the therapeutic options for advanced HCC remain limited and the benefits are temporary. Thus, novel therapeutic targets and more efficacious treatments against this deadly cancer are urgently needed. Here, we investigated the pathogenetic and therapeutic role of eukaryotic initiation factor 4A1 (eIF4A1) in this tumor type. We observed consistent eIF4A1 upregulation in HCC lesions compared with non-tumorous surrounding liver tissues. In addition, eIF4A1 levels were negatively correlated with the prognosis of HCC patients. In HCC lines, the exposure to various eIF4A inhibitors triggered a remarkable decline in proliferation and augmented apoptosis, paralleled by the inhibition of several oncogenic pathways. Significantly, anti-growth effects were achieved at nanomolar concentrations of the eIF4A1 inhibitors and were further increased by the simultaneous administration of the pan mTOR inhibitor, Rapalink-1. In conclusion, our results highlight the pathogenetic relevance of eIF4A1 in HCC and recommend further evaluation of the potential usefulness of pharmacological combinations based on eIF4A and mTOR inhibitors in treating this aggressive tumor.

Differential in vitro effects of targeted therapeutics in primary human liver cancer: importance for combined liver cancer

The incidence of primary liver tumors, hepatocellular carcinoma (HCC), intrahepatic cholangiocellular carcinoma (ICC), and combined HCC/ICC (cHCC/CC) is increasing. For ICC, targeted therapy exists only for a small subpopulation of patients, while for HCC, Sorafenib and Lenvatinib are in use. Diagnosis of cHCC/CC is a great challenge and its incidence is underestimated, bearing the risk of unintended non-treatment of ICC. Here, we investigated effects of targeted inhibitors on human ICC cell lines (HUH28, RBE, SSP25), in comparison to extrahepatic (E)CC lines (EGI1, CCC5, TFK1), and HCC/hepatoblastoma cell lines (HEP3B, HUH7, HEPG2). Cells were challenged with: AKT inhibitor MK-2206; multikinase inhibitors Sorafenib, Lenvatinib and Dasatinib; PI3-kinase inhibitors BKM-120, Wortmannin, LY294002, and CAL-101; and mTOR inhibitor Rapamycin. Dosage of the substances was based on the large number of published data of recent years. Proliferation was analyzed daily for four days. All cell lines were highly responsive to MK-2206. Thereby, MK-2206 reduced expression of phospho(p)-AKT in all ICC, ECC, and HCC lines, which mostly corresponded to reduction of p-mTOR, whereas p-ERK1/2 was upregulated in many cases. Lenvatinib showed inhibitory effects on the two HCC cell lines, but not on HEPG2, ICCs and ECCs. Sorafenib inhibited proliferation of all cells, except the ECC line CCC5. However, at reduced dosage, we observed increased cell numbers in some ICC experiments. Dasatinib was highly effective especially in ICC cell lines. Inhibitory effects were observed with all four PI3-kinase inhibitors. However, cell type-specific differences were also evident here. Rapamycin was most effective in the two HCC cell lines. Our studies show that the nine inhibitors differentially target ICC, ECC, and HCC/hepatoblastoma lines. Caution should be taken with Lenvatinib and Sorafenib administration in patients with cHCC/CC as the drugs may have no effects on, or might even stimulate, ICC.

Conjugated Linoleic Acid Treatment Attenuates Cancerous features in Hepatocellular Carcinoma Cells.

Background A growing number of hepatocellular carcinoma (HCC), and recurrence frequency recently have drawn researchers' attention to alternative approaches. The concept of differentiation therapies (DT) relies on inducing differentiation in HCC cells in order to inhibit recurrence and metastasis. Hepatocyte nuclear factor 4 alpha (HNF4α) is the key hepatogenesis transcription factor and its upregulation may decrease the invasiveness of cancerous cells by suppressing epithelial-mesenchymal transition (EMT). This study aimed to evaluate the effect of conjugated linoleic acid (CLA) treatment, natural ligand of HNF4α, on the proliferation, migration, and invasion capacities of HCC cells in vitro. Materials and Method. Sk-Hep-1 and Hep-3B cells were treated with different doses of CLA or BIM5078 [1-(2′-chloro-5′-nitrobenzenesulfonyl)−2-methylbenzimidazole], an HNF4α antagonist. The expression levels of HNF4a and EMT related genes were evaluated and associated to hepatocytic functionalities, migration, and colony formation capacities, as well as to viability and proliferation rate of HCC cells. Results In both HCC lines, CLA treatment induced HNF4α expression in parallel to significantly decreased EMT marker levels, migration, colony formation capacity, and proliferation rate, whereas BIM5078 treatment resulted in the opposite effects. Moreover, CLA supplementation also upregulated ALB, ZO1, and HNF4α proteins as well as glycogen storage capacity in the treated HCC cells. Conclusion CLA treatment can induce a remarkable hepatocytic differentiation in HCC cells and attenuates cancerous features. This could be as a result of HNF4a induction and EMT inhibition.

CENPO is Associated with Immune Cell Infiltration and is a Potential Diagnostic and Prognostic Marker for Hepatocellular Carcinoma.

PurposeTo examine the expression, clinical significance, and potential regulatory mechanism of centromere protein O (CENPO) in hepatocellular carcinoma (HCC).MethodsCENPO expression in pan-cancer was studied using the TCGA-GTEx database, in HCC and normal liver tissues using the GEO and TCGA databases, and in clinical HCC samples by RT-qPCR. The diagnostic value of CENPO was assessed using receiver operating characteristic curves. Univariate and multivariate regression analyses of factors associated with HCC prognosis were performed. CENPO function and its mechanism in HCC were explored using GO, KEGG, and GSEA analyses of differentially expressed genes (DEGs). Association of CENPO expression with immune cell infiltration and immune checkpoint-associated molecules was conducted using TCGA data and the TIMER2.0 database. Relationships between CENPO expression and DNA methylation were analyzed using the UALCAN and cBioPortal databases. CENPO expression in HCC cell lines was detected using RT-qPCR.ResultsCENPO is upregulated in most cancers, including HCC and cell lines, and is a potential biomarker for HCC diagnosis (AUC = 0.936, 95% CI: 0.911–0.960). Higher CENPO expression was associated with poorer outcomes in patients with HCC (OS, p = 0.004; DSS, p = 0.002; PFI, p < 0.001), and CENPO was an independent predictor of factors influencing overall survival in HCC. DEGs between samples with high and low CENPO levels were enriched in various biological processes, including activation of the G2M checkpoint and other signaling pathways, while CENPO expression correlated with HCC immune cell infiltration and immune checkpoint-associated molecules, as well as CENPO promoter methylation (p < 0.001).ConclusionIn HCC and cell lines, CENPO is overexpressed, a potential diagnostic marker and an indicator of poor prognosis. CENPO may regulate HCC development by influencing nuclear division and tumor immune infiltration and is regulated by methylation, making it a potential target for HCC immunotherapy.

Perfusion culture of multi-layered HepG2 hepatocellular carcinoma cells in a pressure-driven microphysiological system

Here we report the perfusion culture of a multi-layered tissue composed of HepG2 cells (a human hepatoma line) in a pressure-driven microphysiological system (PD-MPS), which we developed previously as a multi-throughput perfusion culture platform. The perfusion culture of multi-layered tissue model was constructed by inserting a modified commercially available permeable membrane insert into the PD-MPS. HepG2 cells were layered on the membrane, and culture medium was perfused both through and below the membrane. The seeded density (number of cells/cm2) of the culture model is 70 times that of static culture in a conventional 35-mm culture dish. Pressure-driven circulation of the medium in our compact device (8.6× 7.0× 4.5cm3), which comprised two perfusion-culture modules and a pneumatic connection port, enabled perfusion culture of two multi-layered tissues (initially 1× 105cells). To obtain insight into the basic functionality of the multi-layered tissues as hepatocytes, we compared albumin production and urea synthesis between perfusion cultures and static cultures. The HepG2 cells grew and secreted increasing amounts of albumin throughout 20 days of perfusion culture, whereas albumin secretion did not increase under static culture conditions. In addition, on day 20, the amount of albumin secreted by the HepG2 cells in the microfluidic device was 68% of that in the conventional culture dish, which was seeded with the same number of cells but had a 70 times larger culture area. These features of high-density culture of functioning cells in a compact device support the application of PD-MPS in single- and multi-organ MPS.

Abstract 3707: Moonlighting function of mitochondrial protein VDAC2 provides a potent pharmacological strategy against selective killing of hepatocellular carcinoma

Abstract Voltage dependent anion channels (VDACs) family of proteins are the most abundant proteins in the outer mitochondrial membrane (OMM). There are three isoforms of VDAC, that are structurally and functionally conserved as far as their ion transport function is concerned. However, there are isoform-specific functions that support distinct pathways. For VDAC2 isoform, an established isoform-specific function is the targeting of the pro-apoptotic Bak protein to the OMM, which stabilizes Bak, leading to its elevated cellular levels. On the surface of OMM, activation and oligomerization of Bak and Bax, another pro-apoptotic protein leads to OMM perforation and release of pro-apoptotic proteins from intermembrane space to the cytoplasm. This is an irreversible step that stimulates the downstream events of apoptotic pathway. Hepatocellular carcinoma (HCC) ranks third in cancer mortality and in the advanced stages is associated with poor prognosis. We observed that unexpectedly, HCC cells are vastly more sensitive to tBid induced apoptosis compared to normal hepatocytes. tBid is a BH3-only pro-apoptotic Bcl-2 family protein, the effect of which is primarily mediated by Bak. We have shown that, in the absence of VDAC2, the Bid-Bak apoptosis pathway is suppressed. VDAC2 protein expression is the lowest in liver and lung among different tissues. We also determined the protein abundances in the HCC lines and normal hepatocytes and found elevated VDAC2 and Bak levels in HCC. Our findings are in line with multiple datasets that show an elevation of VDAC2/Bak expression in human HCC suggesting a potential clinical relevance. We found that combination of an inhibitor of the anti-apoptotic proteins (S63845, a selective Mcl-1 inhibitor), which normally suppresses Bak activation, with an activator of the tBid pathway (TRAIL) enhanced the death of hepatocarcinoma cells with little effect on normal hepatocytes. This treatment strategy was also effective at reducing tumor growth in vivo, but only in tumors expressing VDAC2. Thus, we postulate that increased VDAC2 expression in HCC leads to elevated Bak recruitment to the OMM, which in turn sensitizes HCC to tBid. Therefore, this differential expression provides an excellent opportunity for selective elimination of HCC cells. Citation Format: Piyush Mishra. Moonlighting function of mitochondrial protein VDAC2 provides a potent pharmacological strategy against selective killing of hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3707.

DDX17 protects hepatocytes against oleic acid/palmitic acid-induced lipid accumulation

Hepatic lipid accumulation is an initiation factor in fatty liver disease, and promoting a reduction in hepatic lipid accumulation is an important treatment strategy. DEAD box RNA helicase 17 (DDX17) is a member of the DEAD-box family and a molecular chaperone. Previous studies have demonstrated that DDX17 is a transcriptional coregulator of tumorigenesis, inflammation, and macrophage cholesterol efflux. The liver is the main site for lipid metabolism, and metabolic (dysfunction)-associated fatty liver disease (MAFLD) is one of the most common chronic liver diseases. However, the impact of DDX17 on hepatic lipid accumulation has not been verified. In this study, we found, for the first time, that oleic acid/palmitic acid (OA/PA)-induced lipid accumulation was largely abrogated by DDX17 overexpression in both HepG2 (a human hepatocellular carcinoma line) and Hep1-6 (a murine hepatocellular carcinoma line) cells, and this effect was due to a marked reduction in cellular triglyceride (TG) content. Moreover, the overexpression of DDX17 was accompanied by a significant decrease in the expression of genes involved in de novo fatty acid synthesis (FAS, ACC, and SCD-1) in both HepG2 and Hep1-6 cells. In conclusion, DDX17 protected against OA/PA-induced lipid accumulation in hepatocytes through de novo lipogenesis inhibition.

RAB18 is a key regulator of GalNAc-conjugated siRNA-induced silencing in Hep3B cells

Small interfering RNA (siRNA) therapeutics have developed rapidly in recent years, despite the challenges associated with delivery of large, highly charged nucleic acids. Delivery of siRNA therapeutics to the liver has been established, with conjugation of siRNA to N-acetylgalactosamine (GalNAc) providing durable gene knockdown in hepatocytes following subcutaneous injection. GalNAc binds the asialoglycoprotein receptor (ASGPR) that is highly expressed on hepatocytes and exploits this scavenger receptor to deliver siRNA across the plasma membrane by endocytosis. However, siRNA needs to access the RNA-induced silencing complex (RISC) in the cytoplasm to provide effective gene knockdown, and the entire siRNA delivery process is very inefficient, likely because of steps required for endosomal escape, intracellular trafficking, and stability of siRNA. To reveal the cellular factors limiting delivery of siRNA therapeutics, we performed a genome-wide pooled knockout screen on the basis of delivery of GalNAc-conjugated siRNA targeting the HPRT1 gene in the human hepatocellular carcinoma line Hep3B. Our primary genome-wide pooled knockout screen identified candidate genes that when knocked out significantly enhanced siRNA efficacy in Hep3B cells. Follow-up studies indicate that knockout of RAB18 improved the efficacy of siRNA delivered by GalNAc, cholesterol, or antibodies, but not siRNA delivered by Lipofectamine transfection, suggesting a role for RAB18 in siRNA delivery and intracellular trafficking.

Converged DNA Damage Response Renders Human Hepatocellular Carcinoma Sensitive to CDK7 Inhibition.

Simple SummaryHepatocellular carcinoma (HCC) is the most common type of primary liver cancer. HCC has a dismal five-year mortality estimate of >95%, ranking as the fourth leading cause of cancer-related mortality worldwide. Despite the recent progression in the treatment of HCC with multikinase inhibitors, immunotherapy, and antiangiogenic monoclonal antibodies, among other newly emerging therapeutics, the efficacy has varied among patients, making HCC a high priority for developing novel targeted therapeutic agents. CDK7 has been exploited as a therapeutic target in HCC. In the present study, we demonstrated that HCC cells were highly susceptible to THZ1, a selective covalent CDK7 inhibitor. We further discovered that transcription factor MYC-promoted cell proliferation renders cancer cells hypersensitive to apoptotic cell death with THZ1 treatment. Our findings indicate that targeting CDK7 with THZ1 may be a new plausible strategy for treating HCC, in which MYC plays crucial roles in cell proliferation and tumor growth.Hepatocellular carcinoma (HCC) is a lethal malignancy with high mortality. The inhibition of cyclin-dependent kinase 7 (CDK7) activity has shown therapeutic efficacy in HCC. However, the underlying molecular mechanisms remain elusive. Here, we show that three HCC lines, HepG2, Hep3B, and SK-Hep-1, were highly susceptible to the CDK7 inhibitor THZ1. In mouse models, THZ1 effectively reduced HepG2 tumor growth and tumor weight. THZ1 arrested cell cycle and triggered MYC-related apoptosis in HepG2. To evaluate how MYC protein levels affected THZ1-induced apoptotic cell death, we overexpressed MYC in HepG2 and found that exogenously overexpressed MYC promoted cell cycle progression and increased cells in the S phase. THZ1 drastically engendered the apoptosis of MYC-overexpressing HepG2 cells in the S and G2/M phases. Importantly, transcription-inhibition-induced apoptosis is associated with DNA damage, and exogenous MYC expression further enhanced the THZ1-induced DNA damage response in MYC-overexpressing HepG2 cells. Consistently, in the HepG2 xenografts, THZ1 treatment was associated with DNA-damage-induced cell death. Together, our data indicate that the converged effect of MYC-promoted cell cycle progression and CDK7 inhibition by THZ1 confers the hypersensitivity of HCC to DNA-damage-induced cell death. Our findings may suggest a new therapeutic strategy of THZ1 against HCC.

EV-T synergizes with AZD5582 to overcome TRAIL resistance through concomitant suppression of cFLIP, MCL-1, and IAPs in hepatocarcinoma.

Hepatocellular carcinoma (HCC) is an aggressive malignancy, and its effective treatment has been hampered by drug resistance. Extracellular vesicle (EV) delivery of TNF-related apoptosis-inducing ligand (TRAIL) (EV-T) was demonstrated to be superior to recombinant TRAIL (rTRAIL) for cancer treatment previously. And AZD5582, a potent antagonist of inhibitors of apoptosis proteins (IAPs) can potentiate apoptosis-based cancer therapies. However, the combination of EV-T and AZD5582 has never been examined for their possible apoptosis inducing synergism in cancers. In this study, we proposed and tested the combination of EV-T and AZD5582 as a potential novel therapy for effective treatment of HCC. Two HCC lines Huh7 and HepG2 that are both resistant to rTRAIL were examined. The results confirmed that AZD5582 and EV-T are synergistic for apoptosis induction in some cancer lines including Huh7 and HepG2 while sparing normal cells. More importantly, this study revealed that TRAIL sensitization by AZD5582 is mediated through the concomitant suppression of anti-apoptotic factors including cFLIP, MCL-1, and IAPs (XIAP, Survivin and cIAP-1). Particularly the downregulation of cFLIP and IAP's appeared to be essential and necessary for the synergism between AZD5582 and TRAIL. In vivo, we first time demonstrated that the combined therapy with low doses of AZD5582 and EV-Ts triggered drastically enhanced apoptosis leading to the complete eradication of Huh7 tumor development without any apparent adverse side effects examined. We thus have unraveled the important molecular mechanism underlying TRAIL sensitization by AZD5582, rationalizing the next development of a combination therapy with AZD5582 and EV-T for HCC treatment. KEY MESSAGES: It confirmed the TRAIL sensitization by AZD5582, a potent antagonist of IAPs in hepatocarcinoma. It revealed that the sensitization is via the concomitant suppression of antiapoptotic factors including cFLIP, MCL-1, and IAPs. The downregulation of cFLIP and IAPs like Survivin appeared to be essential and necessary for the synergism between AZD5582 and nanosomal TRAIL. In vivo the combined therapy with AZD5582 and nanosomal TRAIL led to complete eradication of hepatocarcinoma tumors. This study has rationalized the next development of a combination therapy with AZD5582 and nanosomal TRAIL for cancer treatment.

Integrated Analysis of Angiogenesis-Mediated Tumor Immune Microenvironment Pattern in Hepatocellular Carcinoma (HCC) and a Novel Prognostic Model Construction to Predict Patient Outcome.

BackgroundHepatocellular carcinoma (HCC) is a malignant tumor which is famous for its high heterogeneity and complex pathogenesis. Angiogenesis is an important driver of tumor progression and immune-suppressive microenvironment formation.Material/MethodsA training set was acquired from the TCGA-LIHC cohort. An angiogenesis-active subtype was identified by consensus clustering analysis. The tumor subtype’s immune microenvironment pattern was analyzed using quanTIseq. DEGs-mediated biology function was analyzed by enrichment analysis based on GO and KEGG. A prognostic model was constructed using LASSO Cox regression analysis and validated by 2 external datasets derived from GEO and ICGC. Quantitative real-time PCR assay was conducted to analyze CDCA8’s expression status in the HCC line and normal liver cell line.ResultsIn HCC, patients with the angiogenesis-active subtype had a poor prognosis. Angiogenesis can shape the tumor microenvironment into high-M2 microphage infiltration and activity pattern. Here, we identified an angiogenesis-active HCC subtype and constructed an angiogenesis feature-based prognostic model to predict patient outcome. The external validation sets were enrolled to verify the accuracy of this model.ConclusionsOur research demonstrated angiogenesis can confer the tumor immune-suppressive characteristic. We provide a robust method to evaluate the HCC’s angiogenesis potential and help identify the angiogenesis-active subtype. Validation in the external validation cohort further confirmed the accuracy of our prognostic model.