Angiopoietin-like protein 3 and 4 expression 4 and their serum levels in hepatocellular carcinoma

ANGPTL3 overcomes sorafenib resistance via suppression of SNAI1 and CPT1A in liver cancer

Liver cancer, encompassing hepatocellular carcinoma (HCC) and hepatoblastoma, the latter of which primarily occurs in early childhood, is the most common malignant tumor arising from liver and is responsible for a significant number of cancer-related deaths worldwide. Targeted drugs have been used for anti-liver cancer treatment in the advanced stage, while their efficacy is greatly compromised by development of drug resistance. Drug resistance is a complicated process regulated by intrinsic and extrinsic signals and has been associated with poorer prognosis in cancer patients. In the current study, online available dataset analysis uncovered that angiopoietin-like protein 3 (ANGPTL3) manifested lower expression in sorafenib-resistant liver cancer cell lines. Additionally, ANGPTL3 was downregulated in HCC tissues, with its expression positively correlated with good prognosis. Functionally, ectopic expression of ANGPTL3 re-sensitized sorafenib-resistant cells, enhancing the sorafenib-induced reduction in cell viability and migration by suppressing zinc finger protein SNAI1 (SNAI1) expression and the protein stability of carnitine O-palmitoyltransferase 1, liver isoform (CPT1A). Clinical correlation analysis revealed that ANGPTL3 was negatively associated with SNAI1 expression. In conclusion, we identify a novel association between ANGPTL3, SNAI1 and CPT1A on sorafenib therapeutic response. Targeting ANGPTL3/SNAI1/CPT1A axis may serve as a therapeutic approach to improve prognosis of liver cancer patients with sorafenib resistance.

The Pleiotropic Effects of Lipid-Modifying Interventions: Exploring Traditional and Emerging Hypolipidemic Therapies

Atherosclerotic cardiovascular disease poses a significant global health issue, with dyslipidemia standing out as a major risk factor. In recent decades, lipid-lowering therapies have evolved significantly, with statins emerging as the cornerstone treatment. These interventions play a crucial role in both primary and secondary prevention by effectively reducing cardiovascular risk through lipid profile enhancements. Beyond their primary lipid-lowering effects, extensive research indicates that these therapies exhibit pleiotropic actions, offering additional health benefits. These include anti-inflammatory properties, improvements in vascular health and glucose metabolism, and potential implications in cancer management. While statins and ezetimibe have been extensively studied, newer lipid-lowering agents also demonstrate similar pleiotropic effects, even in the absence of direct cardiovascular benefits. This narrative review explores the diverse pleiotropic properties of lipid-modifying therapies, emphasizing their non-lipid effects that contribute to reducing cardiovascular burden and exploring emerging benefits for non-cardiovascular conditions. Mechanistic insights into these actions are discussed alongside their potential therapeutic implications.

ANGPTL3 diminishes the resistance of ovarian cancer to paclitaxel by blocking the PI3K-AKT-mTOR signaling pathway

Angiopoietin-like protein 3 (ANGPTL3) is key in ovarian cancer (OC) cell growth and metastasis, notably by enhancing natural killer cells' capacity for inducing cell toxicity and apoptosis. However, its role in influencing chemotherapy resistance in OC remains ambiguous. In this study, we discovered a correlation between reduced ANGPTL3 levels and a less favorable outcome in OC patients using the Kaplan-Meier Plotter database. Lower levels of ANGPTL3 were detected in paclitaxel (PTX)-resistant OC tissues and cell lines via western blotting and immunohistochemistry. To investigate ANGPTL3's effects, we established SKOV3/PTX and 2780/PTX as PTX-resistant OC cell lines by incrementally increasing PTX exposure and then transfecting them with overexpress ANGPTL3 (OE-ANGPTL3) lentivirus. We conducted various assays such as CCK-8, colony formation, Edu staining, flow cytometry, and transwell to investigate the impact of ANGPTL3 on PTX resistance. Additionally, this effect was examined in a mouse subcutaneous xenograft model. Both in vitro and in vivo experiments demonstrated that ANGPTL3 overexpression mitigated PTX resistance in OC cells by inactivating the PI3K-AKT-mTOR pathway. In summary, our research reveals that ANGPTL3 enhances PTX sensitivity in OC by downregulating the PI3K-AKT-mTOR pathway. The study of this study suggest that ANGPTL3 could serve as a valuable therapeutic target for OC, signifying its clinical relevance in OC management.

Role of the angiopoietin-like protein family in the progression of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver disease, with a range of conditions including non-alcoholic fatty liver, non-alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Currently recognized as the liver component of the metabolic syndrome, NAFLD is intimately linked to metabolic diseases. Angiopoietin-like proteins (ANGPTLs) comprise a class of proteins that resemble angiopoietins structurally. It is closely related to obesity, insulin resistance and lipid metabolism, and may be the critical factor of metabolic syndrome. In recent years, many studies have found that there is a certain correlation between ANGPTLs and the occurrence and progression of NAFLD disease spectrum. This article reviews the possible mechanisms and roles of ANGPTL protein in the pathogenesis and progression of NAFLD.

Extracellular Vesicles Contribute to Viral-Induced Hepatocellular Carcinoma: Understanding Their Involvement in Viral Hepatitis and Their Potential as Biomarkers for Early Hepatocellular Carcinoma Detection

The high global prevalence of hepatitis B and hepatitis C and the poor prognosis of hepatitis B and hepatitis C-associated hepatocellular carcinoma (HCC), necessitates the early diagnosis and treatment of the disease. Recent studies show that cell-to-cell communication via extracellular vesicles (EVs) is involved in the HCC progression. The objective of the following study was to explore the role of EVs in the progression of viral-induced HCC and investigate their potential for the early diagnosis of cancer. First, the mRNA derived from EVs of HCC patients was compared to the mRNA derived from EVs from the healthy controls. Expression analysis of ANGPTL3, SH3BGRL3, and IFITM3 genes from the EVs was done. Afterward, to confirm whether hepatocytes can uptake EVs, HuH7 cells were exposed to EVs, and the expression analysis of downstream target genes (AKT, TNF-α, and MMP-9) in Huh7 cells was done. Transcriptional analysis showed that in the EVs from HCC patients, the expression levels of ANGPTL3, SH3BGRL3, and IFITM3 were significantly increased by 2.62-, 4.3-, and 9.03-folds, respectively. The downstream targets, AKT, TNF-α, and MMP-9, also showed a considerable change of 4.1-, 1.46-, and 5.05-folds, respectively, in Huh7 cells exposed to HCC EVs. In conclusion, the following study corroborates the role of EVs in HCC progression. Furthermore, the significant alteration in mRNA levels of the selected genes demonstrates their potential to be used as possible biomarkers for the early diagnosis of HCC.

Drug development advances in human genetics-based targets

Drug development is a long and costly process, with a high degree of uncertainty from the identification of a drug target to its market launch. Targeted drugs supported by human genetic evidence are expected to enter phase II/III clinical trials or be approved for marketing more quickly, speeding up the drug development process. Currently, genetic data and technologies such as genome-wide association studies (GWAS), whole-exome sequencing (WES), and whole-genome sequencing (WGS) have identified and validated many potential molecular targets associated with diseases. This review describes the structure, molecular biology, and drug development of human genetics-based validated beneficial loss-of-function (LOF) mutation targets (target mutations that reduce disease incidence) over the past decade. The feasibility of eight beneficial LOF mutation targets (PCSK9, ANGPTL3, ASGR1, HSD17B13, KHK, CIDEB, GPR75, and INHBE) as targets for drug discovery is mainly emphasized, and their research prospects and challenges are discussed. In conclusion, we expect that this review will inspire more researchers to use human genetics and genomics to support the discovery of novel therapeutic drugs and the direction of clinical development, which will contribute to the development of new drug discovery and drug repurposing.

Lipid-lowering drugs and cancer: an updated perspective

Statins and non-statin medications used for the management of dyslipidemia have been shown to possess antitumor properties. Since the use of these drugs has steadily increased over the past decades, more knowledge is required about their relationship with cancer. Lipid-lowering agents are heterogeneous compounds; therefore, it remains to be revealed whether anticancer potential is a class effect or related to them all. Here, we reviewed the literature on the influence of lipid-lowering medications on various types of cancer during development or metastasis. We also elaborated on the underlying mechanisms associated with the anticancer effects of antihyperlipidemic agents by linking the reported in vivo and in vitro studies.

Deficiency of angiopoietin-like 4 enhances CD8+ T cell bioactivity via metabolic reprogramming for impairing tumour progression

Angiopoietin-like 4 (ANGPTL4) is a secreted metabolism-modulating glycoprotein involved in the progression of tumours, cardiovascular diseases, metabolic syndrome and infectious diseases. In this study, more CD8+ T cells were activated to be effector T cells in ANGPTL4-/- mice. Impaired growth of tumours implanted in 3LL, B16BL6 or MC38 cells and reduced metastasis by B16F10 cells were observed in ANGPTL4-/- mice. Bone marrow (BM) transplantation experiments displayed that deficiency of ANGPTL4 in either host or BM cells promoted CD8+ T cell activation. However, ANGPTL4 deficiency in CD8+ T cells themselves showed more efficient anti-tumour activities. Recombinant ANGPTL4 protein promoted tumour growth in vivo with the less CD8+ T cell infiltration and it directly downregulated CD8+ T cell activation ex vivo. Transcriptome sequencing and metabolism analysis identified that ANGPTL4-/- CD8+ T cells increased glycolysis and decreased oxidative phosphorylation, which was dependent on the PKCζ-LKB1-AMPK-mTOR signalling axis. Reverse correlation of elevated ANGPTL4 levels in sera and tumour tissues with activated CD8+ T cells in the peripheral blood was displayed in patients with colorectal cancer. These results demonstrated that ANGPTL4 decreased immune surveillance in tumour progression by playing an immune-modulatory role on CD8+ T cells via metabolic reprogramming. Efficient blockade of ANGPTL4 expression in tumour patients would generate an effective anti-tumour effect mediated by CD8+ T cells.

ANGPTL3 affects the metastatic potential and the susceptibility of ovarian cancer cells to natural killer cell-mediated cytotoxicity

High metastatic potential and resistance to immunotherapy lead to poor survival in patients with ovarian cancer. Angiopoietin-like protein 3 is aberrantly expressed and exerts diverse roles in the progression of several cancers. However, its function in ovarian cancer is unknown. Here, decreased expression of angiopoietin-like protein 3 was observed in ovarian cancer tissues and cells. Moreover, patients with high expression of angiopoietin-like protein 3 had longer overall survival and progression-free survival, indicating a good prognosis for patients. Furthermore, angiopoietin-like protein 3 overexpression inhibited ovarian cancer cell proliferation. Concomitantly, high invasion and the occurrence of epithelial-to-mesenchymal transition of cancer cells were restrained after angiopoietin-like protein 3 elevation. Up-regulation of angiopoietin-like protein 3 expression further increased interleukin 2-treated natural killer cell activation by increasing CD69 expression and production of interferon gamma and tumor necrosis factor-alpha when natural killer cells were co-cultured with ovarian cancer cells. Importantly, angiopoietin-like protein 3 overexpression enhanced natural killer cell-evoked cytotoxicity and apoptosis of cancer cells, indicating the pro-tumor killing ability of angiopoietin-like protein 3 for natural killer cells. Mechanistically, angiopoietin-like protein 3 elevation inhibited activation of the Janus Kinase/Signal transducer and activator of transcription 3 signaling in ovarian cancer cells by inhibiting protein expression of phospho-Janus Kinase 2, phospho-Signal transducer and activator of transcription 3, downstream matrix metallopeptidase 2 and programmed cell death 1. Moreover, blocking the Janus Kinase/Signal transducer and activator of transcription 3 pathway via their inhibitor Stattic restrained ovarian cancer cell proliferation, invasion, epithelial-to-mesenchymal transition, and promoted natural killer cell killing to ovarian cancer cells. Thus, these findings reveal that angiopoietin-like protein 3 may act as an anti-oncogenic regulator to inhibit the metastatic potential and enhance the susceptibility of ovarian cancer cells to natural killer cell-mediated killing. Consequently, angiopoietin-like protein 3 may regulate metastatic potential and immune escape from natural killer cells, indicating a promising therapeutic strategy for ovarian cancer.

Screening of novel serum biomarkers for gastric cancer in coastal populations using a protein microarray

Gastric cancer (GC) has high rates of morbidity and mortality, and this phenomenon is particularly evident in coastal regions where local dietary habits favor the consumption of pickled foods such as salted fish and vegetables. In addition, the diagnosis rate of GC remains low due to the lack of diagnostic serum biomarkers. Therefore, in this study, we aimed to identify potential serum GC biomarkers for use in clinical practice. To identify candidate biomarkers of GC, 88 serum samples were first screened using a high-throughput protein microarray to measure the levels of 640 proteins. Then, 333 samples were used to validate the potential biomarkers using a custom antibody chip. ELISA, western blot, and immunohistochemistry were then used to verify the expression of the target proteins. Finally, logistic regression was performed to select serum proteins for the diagnostic model. As a result, five specific differentially expressed proteins, TGFβ RIII, LAG-3, carboxypeptidase A2, Decorin and ANGPTL3, were found to have the ability to distinguish GC. Logistic regression analysis showed that the combination of carboxypeptidase A2 and TGFβ RIII had superior potential for diagnosing GC (area under the ROC curve [AUC] = 0.801). The results suggested that these five proteins alone and the combination of carboxypeptidase A2 and TGFβ RIII may be used as serum markers for the diagnosis of GC.

Angiopoietin-like protein 3 deficiency combined with valsartan administration protects better against podocyte damage in streptozotocin-induced diabetic nephropathy mice

Diabetic nephropathy (DN) is a common leading cause of end-stage renal disease (ESRD). Podocyte injury is a major pathogenesis of DN. Pharmacological inhibition of the renin-angiotensin-aldosterone system (RAAS) is insufficient to fully prevent the development of ESRD. The present investigation aims to evaluate the protective function of valsartan, an angiotensin receptor blocker, alone and in combination with angiopoietin-like protein 3 (Angptl3) knockout against renal damage and podocyte injury in streptozotocin (STZ)-induced diabetic mice. The mice were divided into four groups: normal control group, STZ-induced DN group, valsartan + DN group (val, 100 mg/kg, po), and Angptl3-/- + valsartan + DN group. Tests on kidney function, renal pathology, podocyte ultrastructure, podocyte apoptosis, reactive oxygen species (ROS) production, and autophagy were performed. The combined Angptl3 knockout/valsartan treatment significantly attenuated diabetes-induced renal pathological damage and improved podocyte ultrastructure compared with valsartan alone. The combined administration ameliorated glomerular injury by increasing nephrin, podocin, and CD2-associated protein (CD2AP) expression levels and inhibiting podocyte loss by apoptosis. Compared with valsartan alone, Angptl3-/- and valsartan combination therapy significantly improved the renal function, as demonstrated by decreasing levels of serum urea nitrogen, creatinine, and urinary albumin. Additionally, the combination treatment significantly activated autophagy and reduced the ROS production than valsartan alone. These findings highlight the role of valsartan to Angptl3 knockout could have much better outcome that opens the future for drugs that could inhibit Angptl3.

Obesity and cancer-extracellular matrix, angiogenesis, and adrenergic signaling as unusual suspects linking the two diseases

Obesity is an established risk factor for several human cancers. Given the association between excess body weight and cancer, the increasing rates of obesity worldwide are worrisome. A variety of obesity-related factors has been implicated in cancer initiation, progression, and response to therapy. These factors include circulating nutritional factors, hormones, and cytokines, causing hyperinsulinemia, inflammation, and adipose tissue dysfunction. The impact of these conditions on cancer development and progression has been the focus of extensive literature. In this review, we concentrate on processes that can link obesity and cancer, and which provide a novel perspective: extracellular matrix remodeling, angiogenesis, and adrenergic signaling. We describe molecular mechanisms involved in these processes, which represent putative targets for intervention. Liver, pancreas, and breast cancers were chosen as exemplary disease models. In view of the expanding epidemic of obesity, a better understanding of the tumorigenic process in obese individuals might lead to more effective treatments and preventive measures.

Contribution of organokines in the development of NAFLD/NASH associated hepatocellular carcinoma

Globally the incidence of hepatocellular carcinoma (HCC) is on an upsurge. Evidence is accumulating that liver disorders like nonalcoholic fatty liver disease (NAFLD) and its more progressive form nonalcoholic steatohepatitis (NASH) are associated with increased risk of developing HCC. NAFLD has a prevalence of about 25% and 50%-90% in obese population. With the growing burden of obesity epidemic worldwide, HCC presents a major healthcare burden. While cirrhosis is one of the major risk factors of HCC, available literature suggests that NAFLD/NASH associated HCC also develops in minimum or noncirrhotic livers. Therefore, there is an urgent need to understand the pathogenesis and risk factors associated with NAFLD and NASH related HCC that would help in early diagnosis and favorable prognosis of HCC secondary to NAFLD. Adipokines, hepatokines and myokines are factors secreted by adipocytes, hepatocytes and myocytes, respectively, playing essential roles in cellular homeostasis, energy balance and metabolism with autocrine, paracrine and endocrine effects. In this review, we endeavor to focus on the role of these organokines in the pathogenesis of NAFLD/NASH and its progression to HCC to augment the understanding of the factors stimulating hepatocytes to acquire a malignant phenotype. This shall aid in the development of novel therapeutic strategies and tools for early diagnosis of NAFLD/NASH and HCC.

The Role of ANGPTL Gene Family Members in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is highly aggressive with a poor prognosis and survival rate. Certain ANGPTL members have been implicated in tumor progression. However, the relevance of the ANGPTL gene family to HCC remains poorly understood. In this study, we explored the role of ANGPTLs in the prognosis of HCC.

Methods

From the CCLE database, we studied the expression of ANGPTLs in a range of cancer cell lines. The UCSC, HCCDB, and Human Protein Atlas databases were used to analyze the differences in mRNA and protein expression of ANGPTLs in HCC tissues. Additionally, the correlation between ANGPTL mRNA and methylation levels and clinicopathological features were assessed in the TCGA database. The correlation between ANGPTL mRNA and overall survival was determined by the Kaplan-Meier plotter. cBioPortal database was used to analyze ANGPTL genomic alterations. Genes associated with ANGPTLs were determined by enrichment with KEGG. Moreover, the differentially expressed genes of ANGPTLs were analyzed by the LinkedOmics database, and the KEGG pathway and miRNA targets of ANGPTLs were also enriched.

Results

There was a significant correlation between the ANGPTL members (excluding ANGPTL2) and the prognosis of HCC patients according to the Kaplan-Meier plotter analysis (p < 0.05). ANGPTL1 was the gene with the highest mutation frequency. ANGPTLs are involved in certain pathways that may influence the development of HCC.

Conclusion

In summary, the expression of some members of ANGPTLs was significantly correlated with HCC prognosis, suggesting that the ANGPTL gene family members may be promising molecular markers for HCC treatment and prognosis.

Serum Angiopoietin-Like Protein 4: A Potential Prognostic Biomarker for Prediction of Vascular Invasion and Lymph Node Metastasis in Cholangiocarcinoma Patients

Cholangiocarcinoma (CCA) is a tumor arising from cholangiocytes lining the bile ducts. Vascular invasion and lymph node metastasis are important prognostic factors for disease staging as well as clinical therapeutic decisions for CCA patients. In the present study, we applied CCA sera proteomic analysis to identify a potential biomarker for prognosis of CCA patients. Then, using bioinformatics tools, we identified angiopoietin-like protein 4 (ANGPTL4) which expressed highest signal intensity among candidate proteins in proteomic analysis of CCA sera. Expression of ANGPTL4 in CCA tissues was determined using immunohistochemistry. The results showed that ANGPTL4 was stained at higher level in CCA cells when compared with normal cholangiocytes. The high expression of ANGPTL4 was associated with lymph node metastasis and advanced tumor stage (p = 0.013 and p = 0.031, respectively). Furthermore, serum ANGPTL4 levels in CCA and healthy control (HC) were analyzed using a dot blot assay. And it was found that ANGPTL4 level was significantly higher in CCA than HC group (p < 0.0001). ROC curve analysis revealed that serum ANGPTL4 level was effectively distinguished CCA from healthy patients (cutoff = 0.2697 arbitrary unit (AU), 80.0% sensitivity, 72.7% specificity, AUC = 0.825, p < 0.0001). Serum ANGPTL4 level was associated with vascular invasion and lymph node metastasis (p = 0.0004 and p = 0.006), so that it differentiated CCA with vascular invasion from CCA without vascular invasion (cutoff = 0.5526 AU, 64.9% sensitivity, 92.9% specificity, AUC = 0.751, p = 0.006) and it corresponded to CCA with/without lymph node metastasis (cutoff = 0.5399 AU, 71.4% sensitivity, 70.8% specificity, AUC = 0.691, p = 0.01) by ROC analysis. Serum ANGPTL4 levels showed superior predictive efficiency compared with CA 19-9 and CEA for vascular invasion and lymph node metastasis. In addition, serum ANGPTL4 level was an independent predictive indicator by multivariate regression analysis. In conclusion, serum ANGPTL4 could be a novel prognostic biomarker for prediction of vascular invasion and lymph node metastasis of CCA patients.

Hepatic PTEN Signaling Regulates Systemic Metabolic Homeostasis through Hepatokines-Mediated Liver-to-Peripheral Organs Crosstalk

Liver-derived circulating factors deeply affect the metabolism of distal organs. Herein, we took advantage of the hepatocyte-specific PTEN knockout mice (LPTENKO), a model of hepatic steatosis associated with increased muscle insulin sensitivity and decreased adiposity, to identify potential secreted hepatic factors improving metabolic homeostasis. Our results indicated that protein factors, rather than specific metabolites, released by PTEN-deficient hepatocytes trigger an improved muscle insulin sensitivity and a decreased adiposity in LPTENKO. In this regard, a proteomic analysis of conditioned media from PTEN-deficient primary hepatocytes identified seven hepatokines whose expression/secretion was deregulated. Distinct expression patterns of these hepatokines were observed in hepatic tissues from human/mouse with NAFLD. The expression of specific factors was regulated by the PTEN/PI3K, PPAR or AMPK signaling pathways and/or modulated by classical antidiabetic drugs. Finally, loss-of-function studies identified FGF21 and the triad AHSG, ANGPTL4 and LECT2 as key regulators of insulin sensitivity in muscle cells and in adipocytes biogenesis, respectively. These data indicate that hepatic PTEN deficiency and steatosis alter the expression/secretion of hepatokines regulating insulin sensitivity in muscles and the lipid metabolism in adipose tissue. These hepatokines could represent potential therapeutic targets to treat obesity and insulin resistance.

Angiopoietin-like 3 (ANGPTL3) drives cell proliferation, migration and angiogenesis in cervical cancer via binding to integrin alpha v beta 3

Angiopoietin-like 3 (ANGPTL3) has been uncovered to play an oncogenic role in several kinds of human malignancies. Nevertheless, whether ANGPTL3 functions in cervical cancer (CC) has not yet been reported. This paper is intended to explore the impact of ANGPTL3 on CC cells and elucidate the potential mechanism. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were performed to analyze the ANGPTL3 expression. Western blot was also performed to examine integrin αvβ3 protein level. Cell proliferation was evaluated by MTT assay, EdU staining and Western blot analysis. In addition, the migratory and invasive abilities of cells were, respectively, estimated by wound healing and transwell assays. Tube formation assay was performed to determine endothelial cell angiogenesis. Levels of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR2) were measured by ELISA. As a result, ANGPTL3 expression was significantly higher in CC cells relative to that in normal cervical cells. Silencing of ANGPTL3 suppressed cell proliferation, migration and invasion. Besides, downregulation of ANGPTL3 inhibited human umbilical vein endothelial cell (HUVEC) angiogenesis and repressed protein level of integrin alpha v beta 3 (αvβ3). Upregulation of αvβ3 offsets the inhibitory effect of ANGPTL3 on proliferation, migration and invasion in CC cells. Upregulated expression of αvβ3 promoted blood vessel formation and secretions of VEGF and VEGFR2. In conclusion, ANGPTL3 silencing may serve as a tumor suppressor in CC through integrin αvβ3, which provides a potentially novel therapeutic target for patients with CC.

Systematic Construction and Validation of a Prognostic Model for Hepatocellular Carcinoma Based on Immune-Related Genes

Hepatocellular carcinoma (HCC), a highly aggressive tumor, has high incidence and mortality rates. Recently, immunotherapies have been shown to be a promising treatment in HCC. The results of either the CheckMate-040 or IMbrave 150 trials demonstrate the importance of immunotherapy in the systemic treatment of liver cancer. Thus, in this study, we tried to establish a reliable prognostic model for liver cancer based on immune-related genes (IRGs) and to provide a new insight for immunotherapy of HCC. In this study, we used four datasets that incorporated 851 HCC samples, including 340 samples with complete clinical information from the cancer genome atlas (TCGA) database, to establish an effective model for predicting the prognosis of HCC patients based on the differential expression of IRGs and validated the prognostic model using the data from International Cancer Genome Consortium (ICGC). The top 6 characteristic IRGs identified by protein-protein interaction (PPI) network analysis, MMP9, FOS, CAT, ESR1, ANGPTL3, and KLKB1, were selected for further study. In addition, we assessed the correlations of the six characteristic IRGs with the tumor immune microenvironment, clinical stage, and sensitivity to anti-cancer drugs. We also explored whether the differential expression of the characteristic IRGs was specific to HCC or present in pan-cancer. The expression levels of the six characteristic IRGs were significantly different between most tumor tissues and adjacent normal tissues. In addition, these characteristic IRGs showed a strong association with immune cell infiltration in HCC patients. We found that MMP9 and ESR1 were independent prognostic factors for HCC, while CAT, ESR1, and KLKB1 were associated with the clinical stage. We collected HCC paraffin sections from 24 patients from Xijing hospital to identify the differential expression of the five genes (MMP9, ESR1, CAT, FOS, and KLKB1). Finally, the results of decision curve analysis (DCA) and nomogram revealed that our models provided a prognostic benefit for most HCC patients and the predicted overall survival (OS) was consistent with the actual OS. In conclusion, we systemically constructed a novel prognostic model that provides new insights into HCC.

ANGPTL3 Overexpression Suppresses the Development of Oncogenic Properties in Renal Cell Carcinoma via the Wnt/β-Catenin Signaling Pathway and Predicts Good Prognosis

Angiopoietin-like 3 (ANGPTL3), which is involved in new blood vessel growth, has been reported to exhibit an abnroaml expression in many different cancers. However, the expressing pattern and functions of ANGPTL3 renal cell carcinoma (RCC) were rarely reported. In this study, we observed that ANGPTL3 expression was distinctly downregulated in both RCC specimens from TCGA datasets and cell lines. Survival assays also revealed that patients with low ANGPTL3 expression exhibited a shorter overall survival and disease-free survival than those with high ANGPTL3 expression. Cell counting kit-8 (CCK-8) assay, Colony formation assay, and flow cytometry showed that overexpression of ANGPTL3 distinctly suppressed the proliferation of RCC cells, and promoted apoptosis. Transwell assays and Wound healing assays revealed that ANGPTL3 upregulation suppressed the migration and invasion of RCC cells. Then, we explored whether ANGPTL3 dysregulation influenced the alteration of Wnt/β-catenin signaling using TOP/FOP flash reporter assays and western blot. The results showed that overexpression of ANGPTL3 distinctly suppressed the activity of Wnt/β-catenin signaling. Overall, our results confirmed that overexpression of ANGPTL3 was related to the malignancy and good prognosis of RCC patients, and ANGPTL3 upregulation inhibited the tumor proliferation and metastasis via the Wnt/β-catenin pathway. ANGPTL3 may be a novel therapeutic target and a prognostic biomarker for RCC patients.

Differential Expression of the Host Lipid Regulators ANGPTL-3 and ANGPTL-4 in HCV Infection and Treatment

Host lipid metabolism reprogramming is essential for hepatitis C virus (HCV) infection and progression to severe liver disease. Direct-acting antivirals (DAAs) achieve a sustained virological response (SVR) in most patients, but virus eradication does not always protect against hepatocellular carcinoma (HCC). Angiopoietin-like protein-3 (ANGPTL-3) and angiopoietin-like protein-4 (ANGPTL-4) regulate the clearance of plasma lipids by inhibiting cellular lipase activity and possess emerging roles in tumourigenesis. We used ELISA and RT-qPCR to investigate ANGPTL-3 and ANGPTL-4 expression in HCV patients with characterised fibrosis throughout the natural history of hepatitis C and in long-term HCV infection in vitro, before and after DAA treatment. ANGPTL-3 was decreased in patients with advanced fibrosis compared to other disease stages, while ANGPTL-4 was progressively increased from acute infection to cirrhosis and HCC, peaking at the advanced fibrosis stage. Only ANGPTL-3 mRNA was down-regulated during early infection in vitro, although both ANGPTLs were increased later. DAA treatment did not alter ANGPTL-3 levels in advanced fibrosis/cirrhosis and in HCV infection in vitro, in contrast to ANGPTL-4. The association between ANGPTLs and fibrosis in HCV infection was underlined by an inverse correlation between the levels of ANGPTLs and serum transforming growth factor- β (TGF-β). Collectively, we demonstrate the pivotal role of advanced fibrosis in defining the expression fate of ANGPTLs in HCV infection and after treatment and propose a role for ANGPTL-3 as a contributor to post-treatment deregulation of lipid metabolism that could predispose certain individuals to HCC development.

Emerging roles of angiopoietin-like proteins in inflammation: Mechanisms and potential as pharmacological targets

Angiopoietin-like proteins (ANGPTLs), a family of eight secreted glycoproteins termed ANGTPL1-8, are involved in angiogenesis, lipid metabolism, cancer progression, and inflammation. Their roles in regulating lipid metabolism have been intensively studied, as some ANGPTLs are promising pharmacological targets for hypertriglyceridemia and associated cardiovascular disease. Recently, the emerging roles of ANGPTLs in inflammation have attracted great attention. First, elevated levels of multiple circulating ANGPTLs in inflammatory diseases make them potential disease biomarkers. Second, multiple ANGPTLs regulate acute or chronic inflammation via various mechanisms, including triggering inflammatory signaling through their action as ligands for integrin or forming homo- /hetero-oligomers to regulate signal transduction via extra- or intracellular mechanisms. As dysregulation of the inflammatory response is a critical trigger in many diseases, understanding the roles of ANGPTLs in inflammation will aid in drug/therapy development. Here, we summarize the roles, mechanisms, and potential therapeutic values for ANGPTLs in inflammation and inflammatory diseases.

Structure and Function of Angiopoietin-like Protein 3 (ANGPTL3) in Atherosclerosis

BACKGROUND

Angiopoietin-Like Proteins (ANGPTLs) are structurally related to the angiopoietins. A total of eight ANGPTLs (from ANGPTL1 to ANGPTL8) have been identified so far. Most ANGPTLs possess multibiological functions on lipid metabolism, atherosclerosis, and cancer. Among them, ANGPTL3 has been shown to regulate the levels of Very Low-Density Lipoprotein (VLDL) made by the liver and play a crucial role in human lipoprotein metabolism.

METHOD

A systematic appraisal of ANGPTLs was conducted, focusing on the main features of ANGPTL3 that has a significant role in atherosclerosis.

RESULTS

Angiopoietins including ANGPTL3 are vascular growth factors that are highly specific for endothelial cells, perform a variety of other regulatory activities to influence inflammation, and have been shown to possess both pro-atherosclerotic and atheroprotective effects.

CONCLUSION

ANGPTL3 has been demonstrated as a promising target in the pharmacological management of atherosclerosis. However, many questions remain about its biological functions.

Relationship between hepatic and systemic angiopoietin-like 3, hepatic Vitamin D receptor expression and NAFLD in obesity

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide and an independent risk factor for cardiovascular mortality. Angiopoietin-like proteins (ANGPTLs) are targets for vitamin D receptor (VDR)-mediated gene transcription and this axis may promote NAFLD. ANGPTL3 is a hepatokine which inhibits lipoprotein lipase and its experimentally induced inactivation reduces hepatosteatosis. Little is known on ANGPTL3 in human NAFLD and no data exist on its relationship with hepatic VDR/VD-related genes. The aim of this research was to investigate hepatic ANGPTLs and VDR/VD-related gene expression in human obesity in relation to NAFLD.

METHODS

We conducted a cross-sectional investigation on forty obese subjects with/without NAFLD. We evaluated hepatic ANGPTL3, ANGPTL4, ANGPTL8, LPL, VDR, CYP27A1 and CYP2R1 mRNA expression in liver biopsies by RT-PCR; VDR expression was further investigated by immunohistochemistry; circulating ANGPTL3 was measured by Milliplex assay.

RESULTS

Compared to non-NAFLD, NAFLD individuals had significantly higher hepatic VDR, ANGPTL3 and LPL expression. ANGPTL3 correlated with steatosis grade, LPL, VDR, CYP27A1 and CYP2R1 expression. Plasma ANGPTL3 concentrations were positively associated with clinical/histological markers of NAFLD/NASH and with hepatic ANGPTL3 expression. Greater hepatic VDR expression was the main determinant of hepatic ANGPTL3 after adjusting for multiple confounders.

CONCLUSIONS

Hepatic ANGPTL3 expression correlates with greater VDR expression, presence and severity of NAFLD and translates in increased circulating ANGPTL3, likely as a result of its modulation by up-regulated hepatic VDR in NAFLD. This study provides novel insights to potential mechanisms underlying ANGPTLs-mediated ectopic fat accumulation and NAFLD development in obesity.

Association of pro-inflammatory soluble cytokine receptors early during hepatocellular carcinoma stereotactic radiotherapy with liver toxicity

Plasma levels of soluble factors early during hepatocellular carcinoma (HCC) stereotactic body radiotherapy (SBRT) were evaluated in relation to radiation liver injury, tumor response, and risk of early death. No significant differences were found in baseline plasma levels of AFP, CXCL1, and HGF amongst HCC patients with different Child Pugh scores. Higher levels of sTNFRII (P < 0.001), and lower levels of sCD40L (P < 0.001) and CXCL1 (P = 0.01) following one to two fractions of SBRT were noted in patients who developed liver toxicity vs. those who did not. High circulating levels of AFP (HR 2.16, P = 0.04), sTNFRII (HR 2.27, P = 0.01), and sIL-6R (HR 1.99, P = 0.03) early during SBRT were associated with increased risk of death 3 months post treatment. Plasma levels of the studied factors early during SBRT were not associated with tumor response. A pro-inflammatory systemic environment is associated with development of liver toxicity and increased risk of early death following SBRT.

Association between ANGPTL-4 and the proinflammatory process in cancer cachexia patients

Background

Contradictory results are reported for the role of angiopoietin-like 4 (ANGPTL-4) in the development of cancer-cachexia and inflammation, given its importance in angiogenesis and inflammatory signaling. Our aim was to analyze the levels of ANGPTL-4 in colorectal cancer patients with a stable weight and those with cachexia in order to establish a relationship between ANGPTL-4 and the inflammatory process.

Results

Plasma and tumor levels of ANGPTL-4 were higher in CC in comparison to other groups. A positive association was verified between plasmatic ANGPTL-4 and NFκB levels in tumor from CC. In WSC, we identified an association between the plasmatic ANGPTL-4, IL-15, and IL-10 in tumor and IL-15 in MES. Increased levels of NFκB and TNF-R1 in MES were detected in CC in comparison to WSC. Specifically in CC-group, a positive correlation was found between ANGPTL-4 levels and those of IL-1β, TNF-α, and NFκB in tumor, along with an association between ANGPTL-4 levels with IL-1β and MCP-1 levels in tumor; and ANGPTL-4 and IL-1β levels in MES.

Methods

We studied 102 patients, who were divided into three groups: control patients (C, n=37), cancer patients with a stable weight (WSC, n=23), and cancer-cachexia patients (CC, n=42). Samples of plasma, tumor, mesenteric (MES) and subcutaneous adipose tissue were removed for the determination of ANGPTL-4 levels and other proinflammatory factors.

Conclusions

ANGPTL-4 levels were higher in plasma and tumor of CC-group, and positively associated with pro-inflammatory and pro-tumorigenic factors. Our results suggest an opposite effect of ANGPTL-4 depending on the concentration and presence of cachexia.

Angiopoietin-like 4 binds neuropilins and cooperates with VEGF to induce diabetic macular edema

The majority of patients with diabetic macular edema (DME), the most common cause of vision loss in working-age Americans, do not respond adequately to current therapies targeting VEGFA. Here, we show that expression of angiopoietin-like 4 (ANGPTL4), a HIF-1-regulated gene product, is increased in the eyes of diabetic mice and patients with DME. We observed that ANGPTL4 and VEGF act synergistically to destabilize the retinal vascular barrier. Interestingly, while ANGPTL4 modestly enhanced tyrosine phosphorylation of VEGF receptor 2, promotion of vascular permeability by ANGPTL4 was independent of this receptor. Instead, we found that ANGPTL4 binds directly to neuropilin 1 (NRP1) and NRP2 on endothelial cells (ECs), leading to rapid activation of the RhoA/ROCK signaling pathway and breakdown of EC-EC junctions. Treatment with a soluble fragment of NRP1 (sNRP1) prevented ANGPTL4 from binding to NRP1 and blocked ANGPTL4-induced activation of RhoA as well as EC permeability in vitro and retinal vascular leakage in diabetic animals in vivo. In addition, sNRP1 reduced the stimulation of EC permeability by aqueous fluid from patients with DME. Collectively, these data identify the ANGPTL4/NRP/RhoA pathway as a therapeutic target for the treatment of DME.

The Prospect and Challenges to the Flow of Liquid Biopsy in Africa

Liquid biopsy technologies have the potential to transform cancer patient management as it offers non-invasive diagnosis and real-time monitoring of disease progression and treatment responses. The use of liquid biopsy for non-invasive cancer diagnosis can have pivotal importance for the African continent where access to medical infrastructures is limited, as it eliminates the need for surgical biopsies. To apply liquid biopsy technologies in the African setting, the influence of environmental and population genetic factors must be known. In this review, we discuss the use of circulating tumor cells, cell-free nucleic acids, extracellular vesicles, protein, and other biomolecules in liquid biopsy technology for cancer management with special focus on African studies. We discussed the prospect, barriers, and other aspects that pose challenges to the use of liquid biopsy in the African continent.

High Expression of Angiopoietin-like Protein 4 in Advanced Colorectal Cancer and its Association with Regulatory T Cells and M2 Macrophages

Colorectal cancer (CRC) is one of the most aggressive tumours in the human digestive system. Most CRC patients have poor prognosis due to metastasis and recurrence. Angiopoietin-like 4 (ANGPTL4) is involved in tumour development. Regulatory T (Treg) cells and M2 macrophages promote tumour growth and metastasis. Herein, we explored the changes of ANGPTL4 expression in CRC patients at different stages and observed whether in situ tumour-Treg and -M2 macrophages are correlated with ANGPTL4 expression. Serum ANGPTL4 (sANGPTL4) levels of 70 CRC patients and 10 healthy controls were detected by ELISA. ANGPTL4, Foxp3 and CD163 expression levels in CRC tissues were measured by immunohistochemistry. Recombinant ANGPTL4 (rANGPTL4) proteins were further added into cell-culture systems for induction of Treg cells and M2 macrophages. The results showed both sANGPTL4 and in situ tumour-ANGPTL4 expression levels increased in Dukes C-D stage CRC patients. Foxp3⁺ and CD163⁺ cells in tumour tissue sections were also more intensive in Dukes C-D stage patients than in Dukes A-B stage patients. Foxp3⁺ and CD163⁺ cells in tumour tissues were positively correlated with both tissue and sANGPTL4 expression (P < 0.01). Recombinant ANGPTL4 promoted the induction of murine Treg cells and M2 macrophages ex vivo. Therefore, elevated ANGPTL4 expression could be a marker for advanced CRC. Treg cell and M2 macrophage induction could be one of the mechanisms of tumour promotion mediated by ANGPTL4.

Angiopoietin-like-3 knockout protects against glomerulosclerosis in murine adriamycin-induced nephropathy by attenuating podocyte loss

Background

Angiopoietin-like-3 (Angptl3) knockout is known for its protective effects on podocyte injury and proteinuria in the early stage of adriamycin (ADR) nephropathy. The current study re-evaluated the renoprotective effect of Angptl3 knockout in chronic ADR nephropathy and attempted to explore the mechanism underlying the effect associated with Angptl3 knockout in glomerulosclerosis.

Methods

B6; 129S5 mice were injected with ADR to induce nephropathy. Kidney structure and serum and urine parameters were observed during long-term follow-up. Cultured primary mouse podocytes were exposed to ADR and analyzed for the expression of some relative proteins. Podocyte loss was analyzed in both in vivo and in vitro experiments.

Results

Angptl3 knockout attenuated proteinuria and hypoproteinemia, protected renal structure and function, and improved the survival of mice over the whole process of ADR nephropathy. Furthermore, Angptl3 knockout reduced the numbers of the detached and apoptotic cells in the renal tissue and alleviated podocyte loss in mice with ADR chronic nephropathy, thereby, delaying the glomerulosclerosis formation. Additional results in vitro showed that Angptl3 knockout attenuated ADR-induced primary podocyte loss, including podocyte detachment and apoptosis.

Conclusion

In addition to serving a renoprotective role in the early stage of ADR nephropathy, Angptl3 knockout contributed to disease amelioration throughout the ADR nephropathy process. Angptl3 knockout effectively delayed glomerulosclerosis formation by attenuating podocyte loss through rescuing podocytes from detachment and apoptosis. Angptl3 antagonists or inhibitors might have therapeutic potential in the occurrence and progression of nephropathy.

Electronic supplementary material

The online version of this article (10.1186/s12882-019-1383-1) contains supplementary material, which is available to authorized users.

ANGPTL6-mediated angiogenesis promotes alpha fetoprotein-producing gastric cancer progression

Alpha-fetoprotein (AFP)-producing gastric cancer (AFPGC) is regarded as a rare but highly malignant gastric adenocarcinoma subtype and its clinic pathological presentation mimics hepatocellular carcinoma. However, the underlying mechanism of this disease remains elusive. The level of ANGPTL6 in AFPGC cell lines is much higher than that of common types of gastric cancer cells. A high level of ANGPTL6 confers a poor prognosis and is correlated with the expression of CD34 (an endothelial cell marker). ANGPTL6 promotes endothelial cell migration and tube formation, Moreover, ANGPTL6 knockdown inhibits cancer cell apoptosis and invasiveness. Mechanistically, ANGPTL6 activates the ERK1/2 and AKT pathways. Treatment of ERK1/2 or AKT inhibitor can attenuated cell migration and tube formation. ANGPTL6 loss results in tumor growth in vivo. Our study revealed that ANGPTL6 is an important driver gene of angiogenesis in AFPGC development. These findings provide not only an effective biomarker for diagnosis but also an attractive therapeutic target for use in AFPGC patients.

ANGPTL3: a novel biomarker and promising therapeutic target

Angiopoietin-like protein 3 (ANGPTL3) belongs to a multifunctional secreted protein that mainly expresses in the liver, and is regulated by numerous post-translational modifications, including multiple cleavage and glycosylation. Accumulating evidences have revealed that ANGPTL3 plays a critical role in both biological processes, such as lipid metabolism, angiogenesis and haematopoietic function and pathological changes, including atherosclerosis, carcinogenesis, nephrotic syndrome, diabetes, liver diseases and so on. Thus, ANGPTL3 may serve as a potential biomarker in these diseases. Furthermore, ANGPTL3 signalling pathways including LXR/ANGPTL3, thyroid hormone/ANGPTL3, insulin/ANGPTL3 and leptin/ANGPTL3 are also involved in physiological and pathological processes. Some biological ANGPTL3 inhibitors, chemical drugs and traditional Chinese medicine exert beneficial effects by targeting ANGPTL3 directly or indirectly. Therefore, elucidating the effects and underlying mechanisms of ANGPTL3 is essential to develop promising strategies in the diagnosis and treatment of related diseases.

Mucosal miR-3677 is over-expressed in cirrhotic patients with gastric antral vascular ectasia (GAVE)

INTRODUCTION

Gastric antral vascular ectasia (GAVE) is a rare vasculopathy that associates several diseases, most commonly liver cirrhosis. It usually presents as an occult gastrointestinal bleeding leading to profound iron deficiency anemia. We hypothesized that GAVE is local mucosal pathology dependent on genetic mechanisms, and the purpose of the study was to characterize miRNAs expression in gastric tissue of patients with cirrhosis and GAVE.

MATERIALS AND METHODS

Thirteen patients with GAVE and cirrhosis and 35 healthy subjects were recruited. Microarray analysis and comparative microRNA study was done by quantitative polymerase chain reaction (qPCR). The microarray scores were grouped with use of the hierarchical clusterization analysis and miRNA target prediction was done with TargetScan 6.2 algorithm and Gene Ontology analysis (DIANA-miRPath).

RESULTS

Concentration of miR-3677 in GAVE-affected mucosa was higher by 72% in comparison with GAVE-free mucosa of patients with cirrhosis (33.7 vs. 35.6 PCR cycles; p < .001) and by 45% in comparison with normal mucosa (33.7 vs. 34.9 PCR cycles; p < .05). According to Gene Ontology analysis miR-3677 was related to angiopoietin-like protein 4 (ANGPTL4) gene.

CONCLUSION

GAVE in liver cirrhosis is associated with increased expression of miR-3667 that may be linked with ANGPTL4 gene.

A review of the multifunctionality of angiopoietin-like 4 in eye disease

Angiopoietin-like protein 4 (ANGPTL4) is a multifunctional cytokine regulating vascular permeability, angiogenesis, and inflammation. Dysregulations in these responses contribute to the pathogenesis of ischemic retinopathies such as diabetic retinopathy (DR), age-related macular degeneration (AMD), retinal vein occlusion, and sickle cell retinopathy (SCR). However, the role of ANGPTL4 in these diseases remains controversial. Here, we summarize the functional mechanisms of ANGPTL4 in several diseases. We highlight original studies that provide detailed data about the mechanisms of action for ANGPTL4, its applications as a diagnostic or prognostic biomarker, and its use as a potential therapeutic target. Taken together, the discussions in this review will help us gain a better understanding of the molecular mechanisms by which ANGPTL4 functions in eye disease and will provide directions for future research.

Angiopoietin-Like Proteins in Angiogenesis, Inflammation and Cancer

Altered expression of secreted factors by tumor cells or cells of the tumor microenvironment is a key event in cancer development and progression. In the last decade, emerging evidences supported the autocrine and paracrine activity of the members of the Angiopoietin-like (ANGPTL) protein family in angiogenesis, inflammation and in the regulation of different steps of carcinogenesis and metastasis development. Thus, ANGPTL proteins become attractive either as prognostic or predictive biomarkers, or as novel target for cancer treatment. Here, we outline the current knowledge about the functions of the ANGPTL proteins in angiogenesis, cancer progression and metastasis. Moreover, we discuss the most recent evidences sustaining their role as prognostic or predictive biomarkers for cancer therapy. Although the role of ANGPTL proteins in cancer has not been fully elucidated, increasing evidence suggest their key effects in the proliferative and invasive properties of cancer cells. Moreover, given the common overexpression of ANGPTL proteins in several aggressive solid tumors, and their role in tumor cells and cells of the tumor microenvironment, the field of research about ANGPTL proteins network may highlight new potential targets for the development of future therapeutic strategies.

New insights into ANGPLT3 in controlling lipoprotein metabolism and risk of cardiovascular diseases

Dyslipidemia, characterized by elevation of plasma low density lipoprotein cholesterol (LDL-C), triglyceride (TG) and reduction of plasma high density lipoprotein cholesterol (HDL-C), has been verified as a causal risk factor for cardiovascular diseases (CVD), leading to a high mortality rate in general population. It is important to understand the molecular metabolism underlying dyslipidemia in order to reduce the risk and to develop effective therapeutic approaches against CVD. ANGPTL3 (human) or Angptl3 (mouse), one member of the angiopoietin-like protein (ANGPTL) family, has been identified as an important regulator of lipid metabolism by inhibiting LPL and EL activity. Results have demonstrated that inactivation of Angptl3 in mice could obviously reduce the level of TG, LDL-C and the atherosclerotic lesion size, leading to a lower risk for dyslipidemia and CVD. Additionally, in humans, carriers with homozygous LOF mutations in ANGPTL3 have lower plasma LDL-C, TG levels and lower risk of atherosclerosis compared to the non-carriers. Here, we collect the latest data and results, giving a new insight into the important role of ANGPTL3 in controlling lipoprotein metabolism. Finally, we introduce two update reports on the antisense oligonucleotide and monoclonal antibody-based inactivation of ANGPTL3 in human clinical trials, to identify that ANGPTL3 could be a novel and effective target for the treatment of dyslipidemia and CVD.