Transforming growth factor-β as a therapeutic target in hepatocellular carcinoma

Identification of differentially expressed mRNA/lncRNA modules in acutely regorafenib-treated sorafenib-resistant Huh7 hepatocellular carcinoma cells

The multikinase inhibitor sorafenib is the standard first-line treatment for advanced hepatocellular carcinoma (HCC), but many patients become sorafenib-resistant (SR). This study investigated the efficacy of another kinase inhibitor, regorafenib (Rego), as a second-line treatment. We produced SR HCC cells, wherein the PI3K-Akt, TNF, cAMP, and TGF-beta signaling pathways were affected. Acute Rego treatment of these cells reversed the expression of genes involved in TGF-beta signaling but further increased the expression of genes involved in PI3K-Akt signaling. Additionally, Rego reversed the expression of genes involved in nucleosome assembly and epigenetic gene expression. Weighted gene co-expression network analysis (WGCNA) revealed four differentially expressed long non-coding RNA (DElncRNA) modules that were associated with the effectiveness of Rego on SR cells. Eleven putative DElncRNAs with distinct expression patterns were identified. We associated each module with DEmRNAs of the same pattern, thus obtaining DElncRNA/DEmRNA co-expression modules. We discuss the potential significance of each module. These findings provide insights and resources for further investigation into the potential mechanisms underlying the response of SR HCC cells to Rego.

TGFβR1 inhibition drives hepatocellular carcinoma proliferation through induction of toll-like-receptor signalling

Transforming growth factor (TGF)-β and toll-like receptors (TLRs) have been shown to independently modulate the proliferation of hepatocellular carcinoma (HCC). Since a direct cross-talk between these two signalling pathways in HCC has not been clearly described before, we aimed here to explore the possibility of such interaction. A human HCC tissue array (n = 20 vs. four control samples), human HCC samples (n = 10) and steatohepatitis-driven murine HCC samples (control, NASH and HCC; n = 6/group) were immunostained for TGFβR1, pSMAD2, TRAF6, IRAK1 and PCNA. The results were confirmed by immunoblotting. Effects of constant activation of the SMAD pathway by constitutive expression of ALK5 or knockdown of mediators of TLR signalling, IRAK1 and MyD88, on HCC proliferation, were investigated in the HCC cell line (HUH-7) after treatment with TGFβ1 cytokine or TGFβR1 kinase inhibitor (LY2157299) using PCNA and MTS assay. TGFβR1 expression is decreased in human and murine HCC and associated with downregulated pSMAD2, but increased IRAK1, TRAF6 and PCNA staining. TGFβR1 kinase inhibition abolished the cytostatic effects of TGFβ1 and led to the induction of IRAK1, pIRAK1 and elevated mRNA levels of TLR-9. Overexpression of ALK5 and knockdown of MyD88 or IRAK1 augmented the cytostatic effects of TGFβ1 on HUH-7. In another epithelial HCC cell line, that is, HepG2, TGFβR1 kinase inhibitor similarly elevated cellular proliferation. There is a balance between the canonical SMAD-driven tumour-suppressing arm and the non-canonical tumour-promoting arm of TGFβ signalling. Disruption of this balance, by inhibition of the canonical pathway, induces HCC proliferation through TLR signalling.

IL-37 dampens immunosuppressive functions of MDSCs via metabolic reprogramming in the tumor microenvironment

Interleukin-37 (IL-37) has been shown to inhibit tumor growth in various cancer types. However, the immune regulatory function of IL-37 in the tumor microenvironment is unclear. Here, we established a human leukocyte antigen-I (HLA-I)-matched humanized patient-derived xenograft hepatocellular carcinoma (HCC) model and three murine orthotopic HCC models to study the function of IL-37 in the tumor microenvironment. We found that IL-37 inhibited HCC growth and promoted T cell activation. Further study revealed that IL-37 impaired the immunosuppressive capacity of myeloid-derived suppressor cells (MDSCs). Pretreatment of MDSCs with IL-37 before adoptive transfer attenuated their tumor-promoting function in HCC tumor-bearing mice. Moreover, IL-37 promoted both glycolysis and oxidative phosphorylation in MDSCs, resulting in the upregulation of ATP release, which impaired the immunosuppressive capacity of MDSCs. Collectively, we demonstrated that IL-37 inhibited tumor development through dampening MDSCs' immunosuppressive capacity in the tumor microenvironment via metabolic reprogramming, making it a promising target for future cancer immunotherapy.

Targeting YAP1 to improve the efficacy of immune checkpoint inhibitors in liver cancer: mechanism and strategy

Liver cancer is the third leading of tumor death, including hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). Immune checkpoint inhibitors (ICIs) are yielding much for sufferers to hope for patients, but only some patients with advanced liver tumor respond. Recent research showed that tumor microenvironment (TME) is critical for the effectiveness of ICIs in advanced liver tumor. Meanwhile, metabolic reprogramming of liver tumor leads to immunosuppression in TME. These suggest that regulating the abnormal metabolism of liver tumor cells and firing up TME to turn "cold tumor" into "hot tumor" are potential strategies to improve the therapeutic effect of ICIs in liver tumor. Previous studies have found that YAP1 is a potential target to improve the efficacy of anti-PD-1 in HCC. Here, we review that YAP1 promotes immunosuppression of TME, mainly due to the overstimulation of cytokines in TME by YAP1. Subsequently, we studied the effects of YAP1 on metabolic reprogramming in liver tumor cells, including glycolysis, gluconeogenesis, lipid metabolism, arachidonic acid metabolism, and amino acid metabolism. Lastly, we summarized the existing drugs targeting YAP1 in the treatment of liver tumor, including some medicines from natural sources, which have the potential to improve the efficacy of ICIs in the treatment of liver tumor. This review contributed to the application of targeted YAP1 for combined therapy with ICIs in liver tumor patients.

Differential Modulation of miR-122 Transcription by TGFβ1/BMP6: Implications for Nonresolving Inflammation and Hepatocarcinogenesis

Chronic inflammation is widely recognized as a significant factor that promotes and worsens the development of malignancies, including hepatocellular carcinoma. This study aimed to explore the potential role of microRNAs in inflammation-associated nonresolving hepatocarcinogenesis. By conducting a comprehensive analysis of altered microRNAs in animal models with liver cancer of various etiologies, we identified miR-122 as the most significantly downregulated microRNA in the liver of animals with inflammation-associated liver cancer. Although previous research has indicated the importance of miR-122 in maintaining hepatocyte function, its specific role as either the trigger or the consequence of underlying diseases remains unclear. Through extensive analysis of animals and in vitro models, we have successfully demonstrated that miR-122 transcription is differentially regulated by the immunoregulatory cytokines, by the transforming growth factor-beta 1 (TGFβ1), and the bone morphogenetic protein-6 (BMP6). Furthermore, we presented convincing evidence directly linking reduced miR-122 transcription to inflammation and in chronic liver diseases. The results of this study strongly suggest that prolonged activation of pro-inflammatory signaling pathways, leading to disruption of cytokine-mediated regulation of miR-122, may significantly contribute to the onset and exacerbation of chronic liver disease.

High leukocyte mitochondrial DNA copy number contributes to poor prognosis in breast cancer patients

BACKGROUND

Compelling evidence has indicated a significant association between leukocyte mitochondrial DNA copy number (mtDNAcn) and prognosis of several malignancies in a cancer-specific manner. However, whether leukocyte mtDNAcn can predict the clinical outcome of breast cancer (BC) patients has not been well investigated.

METHODS

The mtDNA copy number of peripheral blood leukocytes from 661 BC patients was measured using a Multiplex AccuCopy™Kit based on a multiplex fluorescence competitive PCR principle. Kaplan-Meier curves and Cox proportional hazards regression model were applied to investigate the association of mtDNAcn with invasive disease-free survival (iDFS), distant disease-free survival (DDFS), breast cancer special survival (BCSS), and overall survival (OS) of patients. The possible mtDNAcn-environment interactions were also evaluated by the Cox proportional hazard regression models.

RESULTS

BC patients with higher leukocyte mtDNA-CN exhibited a significantly worse iDFS than those with lower leukocyte mtDNAcn (5-year iDFS: fully-adjusted model: HR = 1.433[95%CI 1.038-1.978], P = 0.028). Interaction analyses showed that mtDNAcn was significantly associated with hormone receptor status (adjusted p for interaction: 5-year BCSS: 0.028, 5-year OS: 0.022), so further analysis was mainly in the HR subgroup. Multivariate Cox regression analysis demonstrated that mtDNAcn was an independent prognostic factor for both BCSS and OS in HR-positive patients (HR+: 5-year BCSS: adjusted HR (aHR) = 2.340[95% CI 1.163-4.708], P = 0.017 and 5-year OS: aHR = 2.446 [95% CI 1.218-4.913], P = 0.011).

CONCLUSIONS

For the first time, our study demonstrated that leukocyte mtDNA copy number might influence the outcome of early-stage breast cancer patients depending on intrinsic tumor subtypes in Chinese women.

Fibroblasts as Turned Agents in Cancer Progression

Differentiated epithelial cells reside in the homeostatic microenvironment of the native organ stroma. The stroma supports their normal function, their G0 differentiated state, and their expansion/contraction through the various stages of the life cycle and physiologic functions of the host. When malignant transformation begins, the microenvironment tries to suppress and eliminate the transformed cells, while cancer cells, in turn, try to resist these suppressive efforts. The tumor microenvironment encompasses a large variety of cell types recruited by the tumor to perform different functions, among which fibroblasts are the most abundant. The dynamics of the mutual relationship change as the sides undertake an epic battle for control of the other. In the process, the cancer “wounds” the microenvironment through a variety of mechanisms and attracts distant mesenchymal stem cells to change their function from one attempting to suppress the cancer, to one that supports its growth, survival, and metastasis. Analogous reciprocal interactions occur as well between disseminated cancer cells and the metastatic microenvironment, where the microenvironment attempts to eliminate cancer cells or suppress their proliferation. However, the altered microenvironmental cells acquire novel characteristics that support malignant progression. Investigations have attempted to use these traits as targets of novel therapeutic approaches.

Nicotinamide Adenine Dinucleotide Precursor Suppresses Hepatocellular Cancer Progression in Mice

Targeting Nicotinamide adenine dinucleotide (NAD) metabolism has emerged as a promising anti-cancer strategy; we aimed to explore the health benefits of boosting NAD levels with nicotinamide riboside (NR) on hepatocellular carcinoma (HCC). We established three in vivo tumor models, including subcutaneous transplantation tumor model in both Balb/c nude mice (xenograft), C57BL/6J mice (allograft), and hematogenous metastatic neoplasm in nude mice. NR (400 mg/kg bw) was supplied daily in gavage. In-situ tumor growth or noninvasive bioluminescence were measured to evaluate the effect of NR on the HCC process. HepG2 cells were treated with transforming growth factor-β (TGF-β) in the absence/presence of NR in vitro. We found that NR supplementation alleviated malignancy-induced weight loss and metastasis to lung in nude mice in both subcutaneous xenograft and hematogenous metastasis models. NR supplementation decreased metastasis to the bone and liver in the hematogenous metastasis model. NR supplementation also significantly decreased the size of allografted tumors and extended the survival time in C57BL/6J mice. In vitro experiments showed that NR intervention inhibited the migration and invasion of HepG2 cells triggered by TGF-β. In summary, our results supply evidence that boosting NAD levels by supplementing NR alleviates HCC progression and metastasis, which may serve as an effective treatment for the suppression of HCC progression.

Cellular and Molecular Biology of Cancer Stem Cells of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death globally. The cancer stem cells (CSCs) of HCC are responsible for tumor growth, invasion, metastasis, recurrence, chemoresistance, target therapy resistance and radioresistance. The reported main surface markers used to identify liver CSCs include epithelial cell adhesion/activating molecule (EpCAM), cluster differentiation 90 (CD90), CD44 and CD133. The main molecular signaling pathways include the Wnt/β-catenin, transforming growth factors-β (TGF-β), sonic hedgehog (SHH), PI3K/Akt/mTOR and Notch. Patients with EpCAM-positive alpha-fetoprotein (AFP)-positive HCC are usually young but have advanced tumor-node-metastasis (TNM) stages. CD90-positive HCCs are usually poorly differentiated with worse prognosis. Those with CD44-positive HCC cells develop early metastases. Those with CD133 expression have a higher recurrence rate and a shorter overall survival. The Wnt/β-catenin signaling pathway triggers angiogenesis, tumor infiltration and metastasis through the enhancement of angiogenic factors. All CD133+ liver CSCs, CD133+/EpCAM+ liver CSCs and CD44+ liver CSCs contribute to sorafenib resistance. SHH signaling could protect HCC cells against ionizing radiation in an autocrine manner. Reducing the CSC population of HCC is crucial for the improvement of the therapy of advanced HCC. However, targeting CSCs of HCC is still challenging.

The Anti-fibrosis drug Pirfenidone modifies the immunosuppressive tumor microenvironment and prevents the progression of renal cell carcinoma by inhibiting tumor autocrine TGF-β

Transforming growth factor-β (TGF-β) plays a critical role in regulating cell growth and differentiation. Epithelial to mesenchymal transition (EMT) induced by TGF-β promotes cancer cell migration, invasion, and proliferation. Pirfenidone (5-methyl-1-phenyl-2(1 H)-pyridone, PFD), an approved drug for treating pulmonary and renal fibrosis, is a potent TGF-β inhibitor and found reduced incidence of lung cancer and alleviated renal function decline. However, whether PFD plays a role in controlling renal cancer progression is largely unknown. In the present study, we demonstrated that high TGF-β1 expression was negatively associated with ten-year overall survival of patients with renal cancer. Functionally, blockade of TGF-β signaling with PFD significantly suppressed the progression of renal cancer in a murine model. Mechanistically, we revealed that PFD significantly decreased the expression and secretion of TGF-β both in vitro and in vivo tumor mouse model, which further prevented TGF-β-induced EMT and thus cell proliferation, migration, and invasion. Importantly, the downregulation of TGF-β upon PFD treatment shaped the immunosuppressive tumor microenvironment by limiting the recruitment of tumor-infiltrating MDSCs. Therefore, our study demonstrated that PFD prevents renal cancer progression by inhibiting TGF-β production of cancer cells and downstream signaling pathway, which might be presented as a therapeutic adjuvant for renal cancer.

WTAP-mediated m6A modification on circCMTM3 inhibits hepatocellular carcinoma ferroptosis by recruiting IGF2BP1 to increase PARK7 stability

BACKGROUND

Hepatocellular carcinoma (HCC) has poor prognosis and high mortality. CircCMTM3 was significantly up-regulated in HCC. However, the mechanism of circCMTM3 in HCC is not full elucidated.

METHODS

The expression level of circCMTM3, PARK7, GPX4, and Ki67 in HCC cells and tissues were quantified by qRT-PCR, IHC, and Western blotting. The level of GSH, total iron, Fe²⁺, and MDA were detected by their kits. CCK-8 and flow cytometry analysis were used to evaluated cell proliferation and lipid ROS level, respectively. m6A level of circCMTM3 was assessed by MeRIP-PCR. RNA pulldown, RIP, and FISH detected the interaction between circCMTM3, WTAP, and PARK7. Tumor xenograft model was constructed to validate the function of cicrCMTM3 and WTAP.

RESULTS

CircCMTM3 and WTAP were enhanced in HCC tissues and cells. Knockdown of WTAP inhibited m6A modification of circCMTM3, which promoted HCC ferroptosis. circCMTM3 silencing suppressed the expression and stability of PARK7 through binding with IGF2BP1 in HCC cells, which finally induced ferroptosis. In vivo studies demonstrated that silencing WTAP and circCMTM3 suppressed tumor growth and promoted HCC ferroptosis in nude mice by regulating PARK7 signaling.

CONCLUSION

CircCMTM3 promoted the carcinogenesis through inhibiting ferroptosis by recruiting IGF2BP1 to increase PARK7 stability in HCC, suggesting that cicrCMTM3 may be an important marker for HCC treatment.

Therapeutic Effect of Polymeric Nanomicelles Formulation of LY2157299-Galunisertib on CCl4-Induced Liver Fibrosis in Rats

Hepatic fibrosis (HF) is a major cause of liver-related disorders and together with cancer-associated fibroblasts can favor liver cancer development by modulating the tumor microenvironment. Advanced HF, characterized by an excess of extracellular matrix (ECM), is mediated by TGF- β1, that activates hepatic stellate cells (HSCs) and fibroblasts. A TGF-β1 receptor inhibitor, LY2157299 or Galunisertib (GLY), has shown promising results against chronic liver progression in animal models, and we show that it can be further improved by enhancing GLYs bioavailability through encapsulation in polymeric polygalacturonic-polyacrylic acid nanomicelles (GLY-NMs). GLY-NMs reduced HF in an in vivo rat model of liver fibrosis induced by intraperitoneal injection of CCl₄ as shown by the morphological, biochemical, and molecular biology parameters of normal and fibrotic livers. Moreover, GLY-NM was able to induce recovery from HF better than free GLY. Indeed, the encapsulated drug reduces collagen deposition, hepatic stellate cells (HSCs) activation, prevents fatty degeneration and restores the correct lobular architecture of the liver as well as normalizes the serum parameters and expression of the genes involved in the onset of HF. In summary, GLY-NM improved the pharmacological activity of the free TGF- β1 inhibitor in the in vivo HF treatment and thus is a candidate as a novel therapeutic strategy.

Bone morphogenetic proteins, activins, and growth and differentiation factors in tumor immunology and immunotherapy resistance

The TGF-β superfamily is a group of secreted polypeptides with key roles in exerting and regulating a variety of physiologic effects, especially those related to cell signaling, growth, development, and differentiation. Although its central member, TGF-β, has been extensively reviewed, other members of the family-namely bone morphogenetic proteins (BMPs), activins, and growth and differentiation factors (GDFs)-have not been as thoroughly investigated. Moreover, although the specific roles of TGF-β signaling in cancer immunology and immunotherapy resistance have been extensively reported, little is known of the roles of BMPs, activins, and GDFs in these domains. This review focuses on how these superfamily members influence key immune cells in cancer progression and resistance to treatment.

Circular RNA hsa_circ_0062682 Binds to YBX1 and Promotes Oncogenesis in Hepatocellular Carcinoma

Simple Summary

Circular RNA (circRNA) have a role in carcinogenesis in different cancers, also in hepatocellular carcinoma (HCC). The transcriptome analyses of HCC tumours identified an upregulated circRNA hsa_circ_0062682. We show that this circRNA affects several aspects of oncogenesis, which are cell proliferation, migration, and invasion. Using transcriptome analyses we identified modulated signalling pathways and transcription factors, confirming the observed phenotype in cells. We identified Y-box-binding protein 1 (YBX1), a known oncogene and RNA-binding protein, as a binding partner, which was in line with transcriptome analyses. We also identified a cell-specific response to sorafenib after circRNA modulation, which is in line with a heterogeneous molecular pathology of HCC subtypes.

Abstract

Circular RNAs (circRNAs) have been shown to play an important role in the pathogenesis of hepatocellular carcinoma (HCC). By implementing available transcriptomic analyses of HCC patients, we identified an upregulated circRNA hsa_circ_0062682. Stable perturbations of hsa_circ_0062682 in Huh-7 and SNU-449 cell lines influenced colony formation, migration, cell proliferation, sorafenib sensitivity, and additionally induced morphological changes in cell lines, indicating an important role of hsa_circ_0062682 in oncogenesis. Pathway enrichment analysis and gene set enrichment analysis of the transcriptome data from hsa_circ_0062682 knockdown explained the observed phenotypes and exposed transcription factors E2F1, Sp1, HIF-1α, and NFκB1 as potential downstream targets. Biotinylated oligonucleotide pulldown combined with proteomic analyses identified protein interaction partners of which YBX1, a known oncogene, was confirmed by RNA immunoprecipitation. Furthermore, we discovered a complex cell-type-specific phenotype in response to the oncogenic potential of hsa_circ_0062682. This finding is in line with different classes of HCC tumours, and more studies are needed to shed a light on the molecular complexity of liver cancer.

Sirolimus Attenuates Calcineurin Inhibitor-Induced Epithelial-Mesenchymal Transition in Hepatocellular Carcinoma

BACKGROUND

Calcineurin inhibitors (CNIs), which are potent immunosuppressants (ISs), increase the risk for hepatocellular carcinoma (HCC) recurrence after liver transplantation (LTx). Epithelial-mesenchymal transition (EMT) is a key process in which epithelial cancer cells lose their polarity, resulting in cancer progression and metastasis. The aim of this study was to evaluate the effect of sirolimus (SRL) individually and in combination with other ISs to reduce EMT.

METHODS

HCC SK-Hep1 cells were used and various ISs (SRL, tacrolimus, cyclosporine A, or mycophenolate mofetil) were administered at 2 dosages and in combination therapies. Mice were transplanted with SK-Hep1 cells (in the liver) and were monitored after 2 weeks.

RESULTS

The in vitro treatment with SRL showed a dose-dependent attenuation of cell proliferation and migration in case of the individual and IS combination treatments; further, decreased levels of pro-EMT proteins, namely, N-cadherin, transforming growth factor-β, ZEB1, Slug, and Snail were observed. In contrast, E-cadherin expression was upregulated after both the individual and IS combination treatments. These results were also observed in the samples from mice transplanted with the SK-Hep1 cells.

CONCLUSION

The present study demonstrated that SRL reduced HCC metastasis by inhibiting EMT. Thus, our findings provide a rationale for the use of SRL in combination with ISs in HCC LTx patients.

SNAIL driven by a feed forward loop motif promotes TGFβinduced epithelial to mesenchymal transition

Epithelial to Mesenchymal Transition (EMT) plays an important role in tissue regeneration, embryonic development, and cancer metastasis. Several signaling pathways are known to regulate EMT, among which the modulation of TGFβ(Transforming Growth Factor-β) induced EMT is crucial in several cancer types. Several mathematical models were built to explore the role of core regulatory circuit of ZEB/miR-200, SNAIL/miR-34 double negative feedback loops in modulating TGFβinduced EMT. Different emergent behavior including tristability, irreversible switching, existence of hybrid EMT states were inferred though these models. Some studies have explored the role of TGFβreceptor activation, SMADs nucleocytoplasmic shuttling and complex formation. Recent experiments have revealed that MDM2 along with SMAD complex regulates SNAIL expression driven EMT. Encouraged by this, in the present study we developed a mathematical model for p53/MDM2 dependent TGFβinduced EMT regulation. Inclusion of p53 brings in an additional mechanistic perspective in exploring the EM transition. The network formulated comprises a C1FFL moderating SNAIL expression involving MDM2 and SMAD complex, which functions as a noise filter and persistent detector. The C1FFL was also observed to operate as a coincidence detector driving the SNAIL dependent downstream signaling into phenotypic switching decision. Systems modelling and analysis of the devised network, displayed interesting dynamic behavior, systems response to various inputs stimulus, providing a better understanding of p53/MDM2 dependent TGF-βinduced Epithelial to Mesenchymal Transition.

Galunisertib attenuates progression of trauma-induced heterotopic ossification via blockage of Smad2/3 signaling in mice

Heterotopic ossification (HO) is the formation of bony tissues in the extraskeletal system. To date, no effective therapy has been developed for the treatment of HO, although increasing evidences have shown that inhibition of TGF-β signaling has potential as a new therapeutic approach for attenuating HO progression. Results from previous clinical trials have demonstrated that patients with malignant tumors exhibit excellent tolerability to Galunisertib, a TGF-β receptor I kinase inhibitor. However, its therapeutic potential in preventing HO and inhibitory effect on osteogenesis remain unclear. In this study, we demonstrated that intragastrical administration of Galunisertib, at a concentration as low as 10 mg/kg, was not only fairly effective in preventing HO development in a dose-dependent manner, but also generated a non-toxic response in a novel Achilles tendon puncture-induced traumatic HO model in mice. Moreover, Galunisertib treatment in the early phases of HO development, including the inflammatory and chondrogenic period, resulted in better therapeutic effects instead of eliminating already formed bony tissues. Mechanistically, Galunisertib suppressed the osteogenic differentiation capacity of tendon-derived stem cells (TDSCs) by interfering with the Smad2/3 signaling pathway, blocking the phosphorylation of Smad2/3 translocated from cytoplasm into the nucleus to regulate the expression of both osteogenesis-related transcription factors and related proteins. Results from in vivo experiments further validated Galunisertib's effect on HO attenuation, by intercepting the TGF-β/Smad2/3 signaling pathway. In conclusion, our findings demonstrated Galunisertib's potential as a prophylactic drug for the treatment of traumatic HO or other related diseases triggered by over-expressed TGF-β.

Current Strategies for the Treatment of Hepatocellular Carcinoma by Modulating the Tumor Microenvironment via Nano-Delivery Systems: A Review

Liver cancer remains a global health challenge with a projected incidence of over one million cases by 2025. Hepatocellular carcinoma (HCC) is a common primary liver cancer, accounting for about 90% of all liver cancer cases. The tumor microenvironment (TME) is the internal and external environment for tumor development, which plays an important role in tumorigenesis, immune escape and treatment resistance. Knowing that TME is a unique setting for HCC tumorigenesis, exploration of strategies to modulate TME has attracted increasing attention. Among them, the use of nano-delivery systems to deliver therapeutic agents to regulate TME components has shown great potential. TME-modulating nanoparticles have the advantages of protecting therapeutic agents from degradation, enhancing the ability of targeting HCC and reducing systemic toxicity. In this article, we summarize the TME components associated with HCC, including cancer-associated fibroblasts (CAFs), extracellular matrix (ECM), endothelial cells and immune cells, discuss their impact on the HCC progression, and highlight recent studies on nano-delivery systems that modulate these components. Finally, we also discuss opportunities and challenges in this field.

RNA Therapeutic Options to Manage Aberrant Signaling Pathways in Hepatocellular Carcinoma: Dream or Reality?

Despite the early promise of RNA therapeutics as a magic bullet to modulate aberrant signaling in cancer, this field remains a work-in-progress. Nevertheless, RNA therapeutics is now a reality for the treatment of viral diseases (COVID-19) and offers great promise for cancer. This review paper specifically investigates RNAi as a therapeutic option for HCC and discusses a range of RNAi technology including anti-sense oligonucleotides (ASOs), Aptamers, small interfering RNA (siRNA), ribozymes, riboswitches and CRISPR/Cas9 technology. The use of these RNAi based interventions is specifically outlined in three primary strategies, namely, repressing angiogenesis, the suppression of cell proliferation and the promotion of apoptosis. We also discuss some of the inherent chemical and delivery problems, as well as targeting issues and immunogenic reaction to RNAi interventions.

Epithelial–mesenchymal transition: The history, regulatory mechanism, and cancer therapeutic opportunities

Epithelial–mesenchymal transition (EMT) is a program wherein epithelial cells lose their junctions and polarity while acquiring mesenchymal properties and invasive ability. Originally defined as an embryogenesis event, EMT has been recognized as a crucial process in tumor progression. During EMT, cell–cell junctions and cell–matrix attachments are disrupted, and the cytoskeleton is remodeled to enhance mobility of cells. This transition of phenotype is largely driven by a group of key transcription factors, typically Snail, Twist, and ZEB, through epigenetic repression of epithelial markers, transcriptional activation of matrix metalloproteinases, and reorganization of cytoskeleton. Mechanistically, EMT is orchestrated by multiple pathways, especially those involved in embryogenesis such as TGFβ, Wnt, Hedgehog, and Hippo, suggesting EMT as an intrinsic link between embryonic development and cancer progression. In addition, redox signaling has also emerged as critical EMT modulator. EMT confers cancer cells with increased metastatic potential and drug resistant capacity, which accounts for tumor recurrence in most clinic cases. Thus, targeting EMT can be a therapeutic option providing a chance of cure for cancer patients. Here, we introduce a brief history of EMT and summarize recent advances in understanding EMT mechanisms, as well as highlighting the therapeutic opportunities by targeting EMT in cancer treatment.

TGFβ-induced FOXS1 controls epithelial-mesenchymal transition and predicts a poor prognosis in liver cancer

Transforming growth factor beta (TGF-β) plays a key role in tumor progression, notably as a potent inducer of epithelial-mesenchymal transition (EMT). However, all of the molecular effectors driving TGFβ-induced EMT are not fully characterized. Here, we report that forkhead box S1 (FOXS1) is a SMAD (mothers against decapentaplegic)-dependent TGFβ-induced transcription factor, which regulates the expression of genes required for the initial steps of EMT (e.g., snail family transcription repressor 1) and to maintain a mesenchymal phenotype in hepatocellular carcinoma (HCC) cells. In human HCC, we report that FOXS1 is a biomarker of poorly differentiated and aggressive tumor subtypes. Importantly, FOXS1 expression level and activity are associated with a poor prognosis (e.g., reduced patient survival), not only in HCC but also in colon, stomach, and kidney cancers. Conclusion: FOXS1 constitutes a clinically relevant biomarker for tumors in which the pro-metastatic arm of TGF-β is active (i.e., patients who may benefit from targeted therapies using inhibitors of the TGF-β pathway).

Tumor Cell Infiltration into the Brain in Glioblastoma: From Mechanisms to Clinical Perspectives

Glioblastoma is the most common and malignant primary brain tumor, defined by its highly aggressive nature. Despite the advances in diagnostic and surgical techniques, and the development of novel therapies in the last decade, the prognosis for glioblastoma is still extremely poor. One major factor for the failure of existing therapeutic approaches is the highly invasive nature of glioblastomas. The extreme infiltrating capacity of tumor cells into the brain parenchyma makes complete surgical removal difficult; glioblastomas almost inevitably recur in a more therapy-resistant state, sometimes at distant sites in the brain. Therefore, there are major efforts to understand the molecular mechanisms underpinning glioblastoma invasion; however, there is no approved therapy directed against the invasive phenotype as of now. Here, we review the major molecular mechanisms of glioblastoma cell invasion, including the routes followed by glioblastoma cells, the interaction of tumor cells within the brain environment and the extracellular matrix components, and the roles of tumor cell adhesion and extracellular matrix remodeling. We also include a perspective of high-throughput approaches utilized to discover novel players for invasion and clinical targeting of invasive glioblastoma cells.

Structures and biological functions of zinc finger proteins and their roles in hepatocellular carcinoma

Zinc finger proteins are transcription factors with the finger domain, which plays a significant role in gene regulation. As the largest family of transcription factors in the human genome, zinc finger (ZNF) proteins are characterized by their different DNA binding motifs, such as C2H2 and Gag knuckle. Different kinds of zinc finger motifs exhibit a wide variety of biological functions. Zinc finger proteins have been reported in various diseases, especially in several cancers. Hepatocellular carcinoma (HCC) is the third leading cause of cancer-associated death worldwide, especially in China. Most of HCC patients have suffered from hepatitis B virus (HBV) and hepatitis C virus (HCV) injection for a long time. Although the surgical operation of HCC has been extremely developed, the prognosis of HCC is still very poor, and the underlying mechanisms in HCC tumorigenesis are still not completely understood. Here, we summarize multiple functions and recent research of zinc finger proteins in HCC tumorigenesis and progression. We also discuss the significance of zinc finger proteins in HCC diagnosis and prognostic evaluation.

TGF-β1 signaling can worsen NAFLD with liver fibrosis backdrop

Non-Alcoholic Fatty Liver Disease (NAFLD) is characterized by the accumulation of fats in the liver. Relatively benign NAFLD often progresses to fibrosis, cirrhosis, and liver malignancies. Although NAFLD precedes fibrosis, continuous lipid overload keeps fueling fibrosis and the process of disease progression remains unhindered. It is well known that TGF-β1 plays its part in liver fibrosis, yet its effects on liver lipid overload remain unknown. As TGF-β1 signaling has been increasingly attempted to manage liver fibrosis, its actions on the primary suspect (NAFLD) are easily ignored. The complex interaction of inflammatory stress and lipid accumulation aided by mediators scuh as pro-inflammatory interleukins and TGF-β1 forms the basis of NAFLD progression. Anticipatorily, the inhibition of TGF-β1 signaling during anti-fibrotic treatment should reverse the NAFLD though the data remain scattered on this subject to date. TGF-β1 signaling pathway is an important drug target in liver fibrosis and abundant literature is available on it, but its direct effects on NAFLD are rarely studied. This review aims to cover the pathogenesis of NAFLD focusing on the role of the TGF-β1 in the disease progression, especially in the backdrop of liver fibrosis.

Molecular classification of hepatocellular carcinoma: prognostic importance and clinical applications

Hepatocellular carcinoma (HCC) is a lethal human malignancy with a very low overall and long-term survival rate. Poor prognostic outcomes are predominantly associated with HCC due to a huge landscape of heterogeneity found in the deadliest disease. However, molecular subtyping of HCC has significantly improved the knowledge of the underlying mechanisms that contribute towards the heterogeneity and progression of the disease. In this review, we have extensively summarized the current information available about molecular classification of HCC. This review can be of great significance for providing the insight information needed for development of novel, efficient and personalized therapeutic options for the treatment of HCC patients globally.

Optimization and Validation of a Novel Three-Dimensional Co-Culture System in Decellularized Human Liver Scaffold for the Study of Liver Fibrosis and Cancer

Simple Summary

This study aims to overcome the current methodological limitations in discovering new therapeutic targets. Therefore, we optimized and validated a co-culture system using decellularized human liver three-dimensional (3D) scaffolds obtained from healthy and cirrhotic human livers for anti-fibrotic and anti-cancer dual drug screening. Both platforms mimic the naturally healthy and physio-pathological microenvironment and are able to recapitulate the key cellular and molecular events leading to liver fibrogenesis and cancer. This study demonstrates the differences between single versus co-cultures and the usage of human-derived liver 3D ECM scaffolds from healthy and cirrhotic livers. As lead compounds, we used Sorafenib and Regorafenib, first- and second-line drugs, and identified two different drug-induced mechanisms depending on the 3D ECM microenvironment. The 3D ECM scaffolds may represent innovative platforms for disease modeling, biomarker discovery, and drug testing in fibrosis and primary cancer.

Abstract

The introduction of new preclinical models for in vitro drug discovery and testing based on 3D tissue-specific extracellular matrix (ECM) is very much awaited. This study was aimed at developing and validating a co-culture model using decellularized human liver 3D ECM scaffolds as a platform for anti-fibrotic and anti-cancer drug testing. Decellularized 3D scaffolds obtained from healthy and cirrhotic human livers were bioengineered with LX2 and HEPG2 as single and co-cultures for up to 13 days and validated as a new drug-testing platform. Pro-fibrogenic markers and cancer phenotypic gene/protein expression and secretion were differently affected when single and co-cultures were exposed to TGF-β1 with specific ECM-dependent effects. The anti-fibrotic efficacy of Sorafenib significantly reduced TGF-β1-induced pro-fibrogenic effects, which coincided with a downregulation of STAT3 phosphorylation. The anti-cancer efficacy of Regorafenib was significantly reduced in 3D bioengineered cells when compared to 2D cultures and dose-dependently associated with cell apoptosis by cleaved PARP-1 activation and P-STAT3 inhibition. Regorafenib reversed TGF-β1-induced P-STAT3 and SHP-1 through induction of epithelial mesenchymal marker E-cadherin and downregulation of vimentin protein expression in both co-cultures engrafting healthy and cirrhotic 3D scaffolds. In their complex, the results of the study suggest that this newly proposed 3D co-culture platform is able to reproduce the natural physio-pathological microenvironment and could be employed for anti-fibrotic and anti-HCC drug screening.

FOXD3 suppresses epithelial-mesenchymal transition through direct transcriptional promotion of SMAD7 in esophageal squamous cell carcinoma

The transcription factor forkhead box D3 (FOXD3) is an important member of the FOX family, which can maintain the pluripotent properties of cell clusters, neural crest, and trophoblastic progenitor cells in vivo. It has been shown that FOXD3 could affect proliferation, migration, and angiogenesis of various tumors and its deletion and overexpression in organisms will undoubtedly have important influence on the change of cell fate and the occurrence of tumors. However, the underlying functions and molecular mechanisms of FOXD3 in esophageal squamous cell carcinoma (ESCC) have not been fully clarified. According to the present study, the expression levels and functional roles of FOXD3 were investigated, and its prognostic value and molecular mechanisms in tumorigenesis and progression of ESCC were clarified. The expression level of FOXD3 was significantly downregulated in ESCC tissues and cell lines, and correlated with gender, family history of upper gastrointestinal cancer, TNM stage, depth of invasion, lymph node metastasis, and ESCC patients' survival. Moreover, FOXD3 inhibited cells migration and invasion as well as participated in TGF-β1 induced epithelial-mesenchymal transition process. Furthermore, a positive correlation between FOXD3 and SMAD family member 7 (SMAD7) was explored in ESCC. FOXD3 could directly bind to promoter regions of SMAD7 gene, leading to transcriptional promotion of SMAD7 in human esophageal cancer cells. Taken together, FOXD3 may play a tumor suppressor role in ESCC and may be applied as a new therapeutic target and prognostic marker for ESCC.

Traditional Chinese medicine for prevention and treatment of hepatocellular carcinoma: A focus on epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) is one of the most prevalent malignant cancers worldwide. Epithelial-mesenchymal transition (EMT), which endows epithelial cells with mesenchymal properties, plays an important role in the early stages of metastasis. Conventional cancer therapies have promising effects, but issues remain, such as high rates of metastasis and drug resistance. Thus, exploring and evaluating new therapies is an urgent need. Traditional Chinese medicines (TCMs) have been acknowledged for their multi-target and coordinated intervention effects against HCC. Accumulating evidence indicates that TCM can inhibit the malignancy of cells and the progression of EMT in HCC. However, studies on the effects of TCM on EMT in HCC are scarce. In this review, we summarized recent developments in anti-EMT TCMs and formulae, focusing on their underlying pharmacological mechanisms, to provide a foundation for further research on the exact mechanisms through which TCM affects EMT in HCC.

RanBP3 Regulates Proliferation, Apoptosis and Chemosensitivity of Chronic Myeloid Leukemia Cells via Mediating SMAD2/3 and ERK1/2 Nuclear Transport

Abnormal subcellular localization of proteins is an important cause of tumorigenesis and drug resistance. Chromosome region maintenance 1 (CRM1), the nuclear export regulator of most proteins, has been confirmed to be over-expressed in various malignancies and is regarded as an efficient target. But the potential role of the CRM1 cofactor RanBP3 (Ran Binding Protein 3) is left unrevealed in chronic myeloid leukemia (CML). Here, we first detected the level of RanBP3 in CML and found an elevated RanBP3 expression in CML compared with control. Then we used shRNA lentivirus to down-regulated RanBP3 in imatinib sensitive K562 cells and resistant K562/G01 cells and found RanBP3 silencing inhibited cell proliferation by up-regulating p21, induced caspase3-related cell apoptosis, and enhanced the drug sensitivity of IM in vitro. Notably, we observed that RanBP3 silencing restored imatinib sensitivity of K562 cells in NOD/SCID mice. Mechanistically, the nuclear aggregation of SMAD2/3 revealed that tumor suppressor axis (TGF-β)-SMAD2/3-p21 was the anti-proliferation program related to RanBP3 knockdown, and the decrease of cytoplasmic ERK1/2 caused by RanBP3 interference leaded to the down-regulation of anti-apoptosis protein p(Ser112)-BAD, which was the mechanism of increased cell apoptosis and enhanced chemosensitivity to imatinib in CML. In summary, this study revealed the expression and potential role of RanBP3 in CML, suggesting that targeting RanBP3 alone or combined with TKIs could improve the clinical response of CML.

Ailanthoidol, a Neolignan, Suppresses TGF-β1-Induced HepG2 Hepatoblastoma Cell Progression

Ailanthoidol (ATD), a neolignan, possessed an antitumor promotion effect in the mouse skin model in our previous investigation. However, other antitumor properties remain to be elucidated. Liver cancer is a major cause of death in the world, and its prognosis and survival rate are poor. Therefore, the prevention and therapy of liver cancer have received much attention. TGF (transforming growth factor)-β1, a cytokine, plays a critical role in the progression of liver cancer. This study determined the inhibitory effects of ATD on the migration and invasion induced by TGF-β1 in HepG2 hepatoblastoma cells. Furthermore, ATD reduced the TGF-β1-promoted colony number of HepG2 hepatoblastoma cells. In addition to reversing TGF-β1-induced cell scattering, ATD suppressed TGF-β1-induced expression of integrin α3, vimentin, N-cadherin, and matrix metalloproteinase 2 (MMP2). Finally, this study found that ATD significantly inhibited TGF-β1-promoted phosphorylation of p-38 mitogen-activated protein kinase (MAPK) and Smad 2. Furthermore, the administration of SB203580 (p38MAPK inhibitor) suppressed TGF-β1-induced expression of integrin α3, N-cadherin, and MMP2. These results demonstrate a novel mechanism of ATD against progression of liver cancer.

Cyclopentenone Prostaglandins: Biologically Active Lipid Mediators Targeting Inflammation

Cyclopentenone prostaglandins (cyPGs) are biologically active lipid mediators, including PGA2, PGA1, PGJ2, and its metabolites. cyPGs are essential regulators of inflammation, cell proliferation, apoptosis, angiogenesis, cell migration, and stem cell activity. cyPGs biologically act on multiple cellular targets, including transcription factors and signal transduction pathways. cyPGs regulate the inflammatory response by interfering with NF-κB, AP-1, MAPK, and JAK/STAT signaling pathways via both a group of nuclear receptor peroxisome proliferator-activated receptor-gamma (PPAR-γ) dependent and PPAR-γ independent mechanisms. cyPGs promote the resolution of chronic inflammation associated with cancers and pathogen (bacterial, viral, and parasitic) infection. cyPGs exhibit potent effects on viral infections by repressing viral protein synthesis, altering viral protein glycosylation, inhibiting virus transmission, and reducing virus-induced inflammation. We summarize their anti-proliferative, pro-apoptotic, cytoprotective, antioxidant, anti-angiogenic, anti-inflammatory, pro-resolution, and anti-metastatic potential. These properties render them unique therapeutic value, especially in resolving inflammation and could be used in adjunct with other existing therapies. We also discuss other α, β -unsaturated carbonyl lipids and cyPGs like isoprostanes (IsoPs) compounds.

Alterations in MicroRNA gene expression profile in liver transplant patients with hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) can lead to liver failure which renders to liver transplant. miRNAs might be detected as biomarkers in subclinical stage of several hepatobiliary disorders like HCC. Therefore, in the present study, alterations in miRNAs as biomarkers were detected in LT patients with HCC.

Methods

Fourteen tissue samples composed of 5 rejected and 9 non-rejected ones were used for studying the miRNAs expression pattern using LNA-array probe assay and the result was evaluated by in house SYBR Green Real-time PCR protocols on 30 other tissue samples composed of 10 rejected and 20 non-rejected ones for the selected miRNAs. All samples were collected from liver transplanted patients with HCC.

Results

The study results revealed that in rejected patients compared to non-rejected ones, hsa-miR-3158-5p, -4449, -4511, and -4633-5p were up-regulated and hsa-miR-122-3p, -194-5p, 548as-3p, and -4284 were down-regulated. ROC curve analysis also confirmed that miR194-5p and -548as-3p in up-regulated and also, miR-3158-5p, -4449 in down-regulated microRNAs are significantly important molecules in rejection.

Conclusion

Finally, the tissue levels of specific miRNAs (especially hsa-miR-3158-5p, -4449, -194-5p and -548as-3p) significantly correlated with the development of HCC, which can be present as biomarkers after further completing studies.

Supplementary information

The online version contains supplementary material available at 10.1186/s12876-020-01596-2.

CRISPR screens identify tumor-promoting genes conferring melanoma cell plasticity and resistance

Most genetic alterations that drive melanoma development and resistance to targeted therapy have been uncovered. In contrast, and despite their increasingly recognized contribution, little is known about the non-genetic mechanisms that drive these processes. Here, we performed in vivo gain-of-function CRISPR screens and identified SMAD3, BIRC3, and SLC9A5 as key actors of BRAFi resistance. We show that their expression levels increase during acquisition of BRAFi resistance and remain high in persister cells and during relapse. The upregulation of the SMAD3 transcriptional activity (SMAD3-signature) promotes a mesenchymal-like phenotype and BRAFi resistance by acting as an upstream transcriptional regulator of potent BRAFi-resistance genes such as EGFR and AXL. This SMAD3-signature predicts resistance to both current melanoma therapies in different cohorts. Critically, chemical inhibition of SMAD3 may constitute amenable target for melanoma since it efficiently abrogates persister cells survival. Interestingly, decrease of SMAD3 activity can also be reached by inhibiting the Aryl hydrocarbon Receptor (AhR), another druggable transcription factor governing SMAD3 expression level. Our work highlights novel drug vulnerabilities that can be exploited to develop long-lasting antimelanoma therapies.

Argininosuccinate synthase 1 suppresses tumor progression through activation of PERK/eIF2α/ATF4/CHOP axis in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common malignant cancers worldwide, and liver cancer has increased in mortality due to liver cancer because it was detected at an advanced stages in patients with liver dysfunction, making HCC a lethal cancer. Accordingly, we aim to new targets for HCC drug discovery using HCC tumor spheroids.

METHODS

Our comparative proteomic analysis of HCC cells grown in culture as monolayers (2D) and spheroids (3D) revealed that argininosuccinate synthase 1 (ASS1) expression was higher in 3D cells than in 2D cells due to upregulated endoplasmic reticulum (ER) stress responses. We investigated the clinical value of ASS1 in Korean patients with HCC. The mechanism underlying ASS1-mediated tumor suppression was investigated in HCC spheroids. ASS1-mediated improvement of chemotherapy efficiency was observed using high content screening in an HCC xenograft mouse model.

RESULTS

Studies of tumor tissue from Korean HCC patients showed that, although ASS1 expression was low in most samples, high levels of ASS1 were associated with favorable overall survival of patients. Here, we found that bidirectional interactions between ASS1 ER stress responses in HCC-derived multicellular tumor spheroids can limit HCC progression. ASS1 overexpression effectively inhibited tumor growth and enhanced the efficacy of in vitro and in vivo anti-HCC combination chemotherapy via activation of the PERK/eIF2α/ATF4/CHOP axis, but was not dependent on the status of p53 and arginine metabolism.

CONCLUSIONS

These results demonstrate the critical functional roles for the arginine metabolism-independent tumor suppressor activity of ASS1 in HCC and suggest that upregulating ASS1 in these tumors is a potential strategy in HCC cells with low ASS1 expression.

The Role of the Receptor Tyrosine Kinase Axl in Carcinogenesis and Development of Therapeutic Resistance: An Overview of Molecular Mechanisms and Future Applications

Resistance to chemotherapeutic agents by cancer cells has remained a major obstacle in the successful treatment of various cancers. Numerous factors such as DNA damage repair, cell death inhibition, epithelial-mesenchymal transition, and evasion of apoptosis have all been implicated in the promotion of chemoresistance. The receptor tyrosine kinase Axl, a member of the TAM family (which includes TYRO3 and MER), plays an important role in the regulation of cellular processes such as proliferation, motility, survival, and immunologic response. The overexpression of Axl is reported in several solid and hematological malignancies, including non-small cell lung, prostate, breast, liver and gastric cancers, and acute myeloid leukaemia. The overexpression of Axl is associated with poor prognosis and the development of resistance to therapy. Reports show that Axl overexpression confers drug resistance in lung cancer and advances the emergence of tolerant cells. Axl is, therefore, an important candidate as a prognostic biomarker and target for anticancer therapies. In this review, we discuss the consequence of Axl upregulation in cancers, provide evidence for its role in cancer progression and the development of drug resistance. We will also discuss the therapeutic potential of Axl in the treatment of cancer.

Type III TGF-β Receptor Down-Regulation Promoted Tumor Progression via Complement Component C5a Induction in Hepatocellular Carcinoma

Simple Summary

The clinical implications of TGFβR3 downregulation are currently unknown in hepatocellular carcinoma (HCC). Clinically, we identified that HCC patients with low expression levels of tumoral TGFβR3 exhibited significantly late tumor stages and shortened survival outcomes. Moreover, HCC patients developed lower plasma levels of TGFβR3 (sTGFβR3) (8.9 ng/mL) compared to healthy individuals (15.9 ng/mL), which represented a potential diagnostic marker. Similar to tumoral TGFβR3, low levels of plasma sTGFβR3 are also associated with poor clinical outcomes in HCC. To determine its tumor-suppressing capacities, continuous injection of sTGFβR3 in an orthotopic liver tumor model was performed, resulting in 2-fold tumor volume reduction compared to control. Decreased expression of TGFβR3 induced the upregulation of tumoral complement component C5a in HCC, which was found to contribute to poor clinical outcomes and promote tumor progression via a novel function in activating the tumor-promoting macrophages.

Abstract

Background and Aims—Transforming growth factor-beta (TGF-β) signaling orchestrates tumorigenesis and one of the family members, TGF-β receptor type III (TGFβR3), are distinctively under-expressed in numerous malignancies. Currently, the clinical impact of TGFβR3 down-regulation and the underlying mechanism remains unclear in hepatocellular carcinoma (HCC). Here, we aimed to identify the tumor-promoting roles of decreased TGFβR3 expression in HCC progression. Materials and Methods—For clinical analysis, plasma and liver specimens were collected from 100 HCC patients who underwent curative resection for the quantification of TGFβR3 by q-PCR and ELISA. To study the tumor-promoting mechanism of TGFβR3 downregulation, HCC mouse models and TGFβR3 knockout cell lines were applied. Results—Significant downregulation of TGFβR3 and its soluble form (sTGFβR3) were found in HCC tissues and plasma compared to healthy individuals (p < 0.01). Patients with <9.4 ng/mL sTGFβR3 exhibited advanced tumor stage, higher recurrence rate and shorter disease-free survival (p < 0.05). The tumor-suppressive function of sTGFβR3 was further revealed in an orthotopic mouse HCC model, resulting in 2-fold tumor volume reduction. In TGFβR3 knockout hepatocyte and HCC cells, increased complement component C5a was observed and strongly correlated with shorter survival and advanced tumor stage (p < 0.01). Interestingly, C5a activated the tumor-promoting Th-17 response in tumor associated macrophages. Conclusion—TGFβR3 suppressed tumor progression, and decreased expression resulted in poor prognosis in HCC patients through upregulation of tumor-promoting complement C5a.

STMN2 mediates nuclear translocation of Smad2/3 and enhances TGFβ signaling by destabilizing microtubules to promote epithelial-mesenchymal transition in hepatocellular carcinoma

Metastasis remains the major obstacle of improving the survival of patients with hepatocellular carcinoma (HCC). Epithelial-mesenchymal transition (EMT) is critical to cancer metastasis. Successful induction of EMT requires dramatic cytoskeleton rearrangement. However, the significance of microtubule (MT), one of the core components of cell cytoskeleton, in this process remains largely unknown. Here we revealed that STMN2, an important MT dynamics regulator, is barely expressed in normal live tissues but markedly up-regulated in HCCs, especially in those with early recurrence. High STMN2 expression correlates with aggressive clinicopathological features and predicts poor prognosis of HCC patients. STMN2 overexpression in HCC cells promotes EMT, invasion and metastasis in vitro and in vivo, whereas STMN2 knockdown has opposite results. Mechanistically, STMN2 modulates MTs disassembly, disrupts MT-Smad complex, and facilitates release from MT network, phosphorylation and nuclear translocation of Smad2/3 even independent of TGFβ stimulation, thereby enhancing TGFβ signaling. Collectively, STMN2 orchestrates MT disassembly to facilitate EMT via TGF-β signaling, providing a novel insight into the mechanisms underlying cancer metastasis. STMN2 is a promising prognostic biomarker and potential therapeutic target for HCC.

GDF11 rapidly increases lipid accumulation in liver cancer cells through ALK5-dependent signaling

Hepatocellular carcinoma (HCC) is one of the fastest-growing causes of cancer-related mortalities worldwide and this trend is mimicked by the surge of non-alcoholic fatty liver disease (NAFLD). Altered hepatic lipid metabolism promotes HCC development through inflammation and activation of oncogenes. GDF11 is a member of the TGF-β superfamily and recent data have implicated GDF11 as an anti-aging factor that can alleviate high-fat diet induced obesity, hyperglycemia, insulin resistance and NAFLD. However, its role in hepatic lipid metabolism is still not fully delineated. The aim of the present study was to characterize the role of GDF11 in hepatic and HCC cells lipid accumulation. To achieve this, we performed imaging, biochemical, lipidomic, and transcriptomic analyses in primary hepatocytes and in HCC cells treated with GDF11 to study the GDF11-activated signaling pathways. GDF11 treatment rapidly triggered ALK5-dependent SMAD2/3 nuclear translocation and elevated lipid droplets in HCC cells, but not in primary hepatocytes. In HCC cells, ALK5 inhibition hampered GDF11-mediated SMAD2/3 signaling and attenuated lipid accumulation. Using ultra-high-performance liquid chromatography/mass spectrometry, we detected increased accumulation of longer acyl-chain di/tri-acylglycerols and glycerophospholipids. Unbiased transcriptomic analysis identified TGF-β and PI3K-AKT signaling among the top pathways/cellular processes activated in GDF11 treated HCC cells. In summary, GDF11 supplementation promotes pro-lipogenic gene expression and lipid accumulation in HCC cells. Integration of our "omics" data pointed to a GDF11-induced upregulation of de novo lipogenesis through activation of ALK5/SMAD2/3/PI3K-AKT pathways. Thus, GDF11 could contribute to metabolic reprogramming and dysregulation of lipid metabolism in HCC cells, without effects on healthy hepatocytes.

Suppression of TGF-beta activity with remobilization attenuates immobilization-induced joint contracture in rats

BACKGROUND

Joint contracture is a common complication of joint injury. This study aimed to assess the effect of inhibiting the transforming growth factor-β (TGF-β) signaling during joint immobilization and remobilization on immobilization-induced joint contracture in rats.

METHODS

The knees of rats were immobilized using Kirschner wires following trauma to the femoral condyles to generate joint contracture. After immobilization, levels of TGF-β and passive extension range of motion (ROM) were measured at different time points, joints were histologically analyzed by hematoxylin and eosin (H&E) and Masson trichrome staining, and the expression of inflammatory or fibrosis-related mediators, including interleukin-1β (IL-1β), phosphorylated Smad2/3 (p-Smad2/3), α-smooth muscle actin (α-SMA) and collagen types I (Col 1) and III (Col 3), were examined in joint capsules using immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). Rats were also treated with LY2157299, a TGF-β receptor I kinase inhibitor, at different stages of immobilization and remobilization.

RESULTS

TGF-β1 levels in the serum and the number of p-Smad2/3⁺ cells in the joint capsule were significantly elevated after immobilization. ROM decreased during the 6 weeks of immobilization and partly recovered after remobilization. After treatment with LY2157299 during immobilization, the restricted ROM moderately increased, but this effect was stronger when combined with active motion. Mechanistically, the expression of IL-1β, TGF-β, fibrosis-related factors, and the density of collagen significantly decreased after treatment with LY2157299.

CONCLUSIONS

Inhibiting TGF-β signaling paired with active motion effectively attenuated the formation of immobilization-induced joint contracture in rats.

Adamantane-linked isothiourea derivatives suppress the growth of experimental hepatocellular carcinoma via inhibition of TLR4-MyD88-NF-κB signaling

In this study, in vitro cytotoxic effects of seven adamantyl isothiourea derivatives were evaluated against five human tumor cell lines using the MTT assay. Compounds 5 and 6 were found to be the most active derivatives particularly against hepatocellular carcinoma (HCC). To decipher the potential mechanisms involved, in vivo studies were conducted in rats by inducing HCC via chronic thioacetamide (TAA) administration (200 mg/kg, i.p., twice weekly) for 16 weeks. Compounds 5 and 6 were administered to HCC rats, at a dose of 10 mg/kg/day, for further 2 weeks. In vitro and in vivo antitumor activities of compounds 5 and 6 were compared to those of the anticancer drug doxorubicin (DOXO). In the HCC rat model, compounds 5 and 6 significantly reduced serum levels of ALT, AST with ALP and α-fetoprotein. H & E and Masson trichrome staining revealed that both compounds suppressed hepatocyte tumorigenesis and diminished fibrosis, inflammation and other histopathological alterations. Mechanistically, compounds 5 and 6 markedly decreased protein expression levels of α-SMA, sEH, p-NF-κB p65, TLR4, MyD88, TRAF-6, TNF-α, IL-1β and TGF-β1, whereas they increased caspase-3 expression in liver tissues of HCC rats. In most analyses, the effects of compound 6 were more comparable to DOXO than compound 5. These findings suggested that the compounds 5 and 6 displayed in vitro and in vivo cytotoxic potential against HCC, probably via inhibition of TLR4-MyD88-NF-κB signaling.

Molecular crosstalk between Y5 receptor and neuropeptide Y drives liver cancer

Hepatocellular carcinoma (HCC) is clearly age-related and represents one of the deadliest cancer types worldwide. As a result of globally increasing risk factors including metabolic disorders, the incidence rates of HCC are still rising. However, the molecular hallmarks of HCC remain poorly understood. Neuropeptide Y (NPY) and NPY receptors represent a highly conserved, stress-activated system involved in diverse cancer-related hallmarks including aging and metabolic alterations, but its impact on liver cancer had been unclear. Here, we observed increased expression of NPY5 receptor (Y5R) in HCC, which correlated with tumor growth and survival. Furthermore, we found that its ligand NPY was secreted by peritumorous hepatocytes. Hepatocyte-derived NPY promoted HCC progression by Y5R activation. TGF-β1 was identified as a regulator of NPY in hepatocytes and induced Y5R in invasive cancer cells. Moreover, NPY conversion by dipeptidylpeptidase 4 (DPP4) augmented Y5R activation and function in liver cancer. The TGF-β/NPY/Y5R axis and DPP4 represent attractive therapeutic targets for controlling liver cancer progression.

Comprehensive analysis of key lncRNAs in HCV-positive hepatocellular carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Despite the therapeutic advances in HCC in the past few decades, the mortality rate of HCC is still high. Hepatitis C (HCV) infection is one of the major etiological risk factors of HCCs. However, the underlying mechanisms of HCV-induced hepatocarcinogenesis remain largely unclear.

MATERIAL AND METHODS

Our study represented the comprehensive analysis of differentially expressed lncRNAs in HCV-positive HCC for the first time by analyzing the public dataset GSE17856. Co-expression network and gene ontology (GO) analysis revealed the functions of those differentially expressed lncRNAs.

RESULTS

We identified 256 upregulated lncRNAs and 198 downregulated lncRNAs in HCV- positive HCC compared to the normal liver tissues. Co-expression network and GO analysis showed that these lncRNAs were involved in regulating metabolism, energy pathways, proliferation and the immune response. Seven lncRNAs (LOC341056, CCT6P1, PTTG3P, LOC643387, LOC100133920, C3P1 and C22orf45) were identified as key lncRNAs and co-expressed with more than 100 differentially expressed genes (DEGs) in HCV-related HCC. Kaplan-Meier analysis showed that higher expression levels of LOC643387, PTTG3P, LOC341056, CCT6P1 and lower expression levels of C3P1 and C22orf45 were associated with shorter survival time in the TCGA dataset.

CONCLUSIONS

We believe that this study can provide novel potential therapeutic and prognostic biomarkers for HCV-positive HCC.

TGFβ-Directed Therapeutics: 2020

The transforming growth factor-beta (TGFβ) pathway is essential during embryo development and in maintaining normal homeostasis. During malignancy, the TGFβ pathway is co-opted by the tumor to increase fibrotic stroma, to promote epithelial to mesenchymal transition increasing metastasis and producing an immune-suppressed microenvironment which protects the tumor from recognition by the immune system. Compelling preclinical data demonstrate the therapeutic potential of blocking TGFβ function in cancer. However, the TGFβ pathway cannot be described as a driver of malignant disease. Two small molecule kinase inhibitors which block the serine-threonine kinase activity of TGFβRI on TGFβRII, a pan-TGFβ neutralizing antibody, a TGFβ trap, a TGFβ antisense agent, an antibody which stabilizes the latent complex of TGFβ and a fusion protein which neutralizes TGFβ and binds PD-L1 are in clinical development. The challenge is how to most effectively incorporate blocking TGFβ activity alone and in combination with other therapeutics to improve treatment outcome.

Manipulating dynamic tumor vessel permeability to enhance polymeric micelle accumulation

Selectively delivering anticancer drugs to solid tumors while avoiding their accumulation in healthy tissues is a major goal in polymeric micelle research. We have recently discovered that the extravasation and permeation of polymeric micelles occur in a dynamic manner characterized by vascular bursts followed by a brief and vigorous outward flow of fluid (called "nano-eruptions"). Nano-eruptions allow delivery of polymeric micelle-associated drugs, though delivery can be heterogeneous both among tumors and within an individual tumor, leading to suboptimal intratumoral distribution. Manipulation of nano-eruptions is expected to improve the efficiency of drug delivery systems (DDSs). By using compounds that affect the intratumoral environment, i.e. a TGF-β inhibitor and chloroquine, the possibility of manipulating nano-eruptions to improve delivery efficiency was investigated. Both compounds were tested in a mouse xenograft model of GFP-labeled pancreatic tumor cells by tracing nano-eruption events and extravasation of size-modulated polymeric micelles in real-time through intravital confocal laser scanning microscopy. The TGF-β inhibitor increased the number of dynamic vents, extended duration time, and generated dynamic vents with a wide range of sizes. Chloroquine did not affect the frequency of nano-eruptions, but it increased tumor vessel diameter, maximum nano-eruption area, and maximum radial increase. Both the TGF-β inhibitor and chloroquine augmented nano-eruptions to diffuse polymeric micelles through tumor stroma, and these medications had a greater effect on the polymeric micelles with larger size, i.e. 70-nm, than on the smaller polymeric micelles having a 30-nm diameter. The results indicate that TGF-β inhibition and chloroquine refashion the intratumoral distribution of DDSs by different mechanisms.

Modulation of the TGF-β signaling pathway by long noncoding RNA in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a type of liver cancer with poor prognosis. There have been demonstrated to exist many possible mechanisms in HCC tumorigenesis, and recent investigations have provided some promising therapy targets. However, further mechanisms remain to be researched to improve the therapeutic strategy and diagnosis of HCC. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine which plays critical roles in networks of different cellular processes, and TGF-β signaling has been found to participate in tumor initiation and development of HCC in recent years. Moreover, among the molecules and signaling pathways, researchers paid more attention to lncRNAs (long non-coding RNAs), but the connection between lncRNAs and TGF-βremain poorly understood. In this review, we conclude the malignant procedure which lncRNAs and TGF-β involved in, and summarize the mechanisms of lncRNAs and TGF-βin HCC initiation and development. Furthermore, the interaction between lncRNA and TGF-β are paid more attention, and the potential therapy targets are mentioned.

Targeted treatment of alcoholic liver disease based on inflammatory signalling pathways

Targeted therapy is an emerging treatment strategy for alcoholic liver disease (ALD). Inflammation plays an important role in the occurrence and development of ALD, and is a key choice for its targeted treatment, and anti-inflammatory treatment has been considered beneficial for liver disease. Surprisingly, immune checkpoint inhibitors have become important therapeutic agents for hepatocellular carcinoma (HCC). Moreover, studies have shown that the combination of inflammatory molecule inhibitors and immune checkpoint inhibitors can exert better effects than either alone in mouse models of HCC. This review discusses the mechanism of hepatic ethanol metabolism and the conditions under which inflammation occurs. In addition, we focus on the potential molecular targets in inflammatory signalling pathways and summarize the potential targeted inhibitors and immune checkpoint inhibitors, providing a theoretical basis for the targeted treatment of ALD and the development of new combination therapy strategies for HCC.

Correlation of PPM1A Downregulation with CYP3A4 Repression in the Tumor Liver Tissue of Hepatocellular Carcinoma Patients

BACKGROUND AND OBJECTIVE

In many patients with hepatocellular carcinoma (HCC), cytochrome P450 3A4 (CYP3A4) expression has been reported to be significantly reduced in the tumor liver tissue. Moreover, this CYP3A4 repression is associated with decreased CYP3A4-mediated drug metabolism in the tumor liver tissue. However, the underlying mechanisms of CYP3A4 repression are not fully understood. We have previously shown that Mg²⁺/Mn²⁺-dependent phosphatase 1A (PPM1A) positively regulates human pregnane X receptor (hPXR)-mediated CYP3A4 expression in a PPM1A expression-dependent manner. We sought to determine whether PPM1A expression is downregulated and whether PPM1A downregulation is correlated with CYP3A4 repression in the tumor liver tissue of HCC patients.

METHODS

Quantitative RT-PCR and western blot analyses were performed to study mRNA and protein expression, respectively. Cell-based reporter gene assays were conducted to examine the hPXR transactivation of CYP3A4 promoter activity.

RESULTS

Arginase-1 and glypican-3 gene expression studies confirmed that the tumor samples used in our study originate from HCC livers but not non-hepatocellular tumors. mRNA and protein expression of PPM1A and CYP3A4 was found to be significantly repressed in the tumor liver tissues compared to the matched non-tumor liver tissues. In the reporter gene assays, elevated PPM1A levels counteracted the inhibition of hPXR-mediated CYP3A4 promoter activity by signaling pathways that are upregulated in HCC, suggesting that decreased PPM1A levels in HCC could not fully counteract the hPXR-inhibiting signaling pathways.

CONCLUSIONS

Together, these results are consistent with the conclusion that PPM1A downregulation in the tumor liver tissue of HCC patients correlates with CYP3A4 repression. Downregulation of PPM1A levels in the tumor liver tissue may contribute to reduced hPXR-mediated CYP3A4 expression, and provide a novel mechanism of CYP3A4 repression in the tumor liver tissue of HCC patients.

Gingold J. Dysregulated PJA1-TGF-β signaling in cancer stem cell-associated liver cancers

The transforming growth factor beta (TGF-β) signaling pathway plays important roles in cell differentiation, stem cell modulation, organ lineage, and immune suppression. TGF-β signaling is negatively regulated by the ubiquitin-proteasome pathway. Although mouse models of cancer arising from a defective TGF-β pathway clearly demonstrate the tumor-suppressive role of TGF-β, the underlying mechanism by which a defective TGF-β pathway triggers liver cancer development is poorly understood. This review summarizes key findings from our recent studies connecting TGF-β to hepatic oncogenesis and highlights the vulnerability of TGF-β signaling to PJA1-mediated ubiquitination. TGF-β, together with the chromatin insulator CCCTC-binding factor (CTCF), epigenetically and transcriptionally regulate tumor promoter genes, including IGF2 and TERT, in TGF-β-defective mice and in human liver cancers. Dysfunction of the TGF-β-regulated SPTBN1/SMAD3/CTCF complex increases stem cell-like properties in hepatocellular carcinoma (HCC) cells and enhances tumorigenesis in tumor-initiating cells in a mouse model. PJA1, a novel E3 ubiquitin ligase, is a key negative regulator of TGF-β signaling. PJA1 overexpression is detected in HCCs and is sufficient to suppress SMAD3- and SPTBN1-mediated TGF-β tumor suppressor signaling, promoting HCC proliferation. Dysregulated PJA1-TGF-β signaling activates oncogenic genes and promotes tumorigenesis in human liver cancers. In addition, inhibition of PJA1 by treatment with E3 ligase inhibitors restores TGF-β tumor-suppressor function and suppresses liver cancer progression. These new findings suggest potential therapeutic avenues for targeting dysregulated PJA1-TGF-β signaling via cancer stem cells in liver cancers.

Identifying cancer-associated fibroblasts as emerging targets for hepatocellular carcinoma

The tumor microenvironment (TME) is a complex multicellular functional compartment that includes fibroblasts, myofibroblasts, endothelial cells, immune cells, and extracellular matrix (ECM) elements. The microenvironment provides an optimum condition for the initiation, growth, and dissemination of hepatocellular carcinoma (HCC). As one of the critical and abundant components in tumor microenvironment, cancer-associated fibroblasts (CAFs) have been implicated in the progression of HCC. Through secreting various growth factors and cytokines, CAFs contribute to the ECM remodeling, stem features, angiogenesis, immunosuppression, and vasculogenic mimicry (VM), which reinforce the initiation and development of HCC. In order to restrain the CAFs-initiated HCC progression, current strategies include targeting specific markers, engineering CAFs with tumor-suppressive phenotype, depleting CAFs’ precursors, and repressing the secretions or downstream signaling. In this review, we update the emerging understanding of CAFs in HCC, with particular emphasis on cellular origin, phenotypes, biological functions and targeted strategies. It provides insights into the targeting CAFs for HCC treatment.

Inhibiting IRE1α-endonuclease activity decreases tumor burden in a mouse model for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a liver tumor that usually arises in patients with cirrhosis. Hepatic stellate cells are key players in the progression of HCC, as they create a fibrotic micro-environment and produce growth factors and cytokines that enhance tumor cell proliferation and migration. We assessed the role of endoplasmic reticulum (ER) stress in the cross-talk between stellate cells and HCC cells. Mice with a fibrotic HCC were treated with the IRE1α-inhibitor 4μ8C, which reduced tumor burden and collagen deposition. By co-culturing HCC-cells with stellate cells, we found that HCC-cells activate IREα in stellate cells, thereby contributing to their activation. Inhibiting IRE1α blocked stellate cell activation, which then decreased proliferation and migration of tumor cells in different in vitro 2D and 3D co-cultures. In addition, we also observed cell-line-specific direct effects of inhibiting IRE1α in tumor cells.