Further pharmacological and genetic evidence for the efficacy of PlGF inhibition in cancer and eye disease.

Our findings that PlGF is a cancer target and anti-PlGF is useful for anticancer treatment have been challenged by Bais et al. Here we take advantage of carcinogen-induced and transgenic tumor models as well as ocular neovascularization to report further evidence in support of our original findings of PlGF as a promising target for anticancer therapies. We present evidence for the efficacy of additional anti-PlGF antibodies and their ability to phenocopy genetic deficiency or silencing of PlGF in cancer and ocular disease but also show that not all anti-PlGF antibodies are effective. We also provide additional evidence for the specificity of our anti-PlGF antibody and experiments to suggest that anti-PlGF treatment will not be effective for all tumors and why. Further, we show that PlGF blockage inhibits vessel abnormalization rather than density in certain tumors while enhancing VEGF-targeted inhibition in ocular disease. Our findings warrant further testing of anti-PlGF therapies.

Elevated SLC1A5 associated with poor prognosis and therapeutic resistance to transarterial chemoembolization in hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common malignant tumor, and glutamine is vital for tumor cells. The role of glutamine transporter SLC1A5 in tumor progression and transarterial chemoembolization (TACE) efficacy is under study. This research seeks to determine the impact of SLC1A5 expression on the prognosis and TACE efficacy of HCC and elucidate its mechanisms. METHODS: SLC1A5 expression in HCC, correlation with patient outcomes, and response to TACE were studied in an open access liver cancer dataset and confirmed in our cohort. Additionally, the correlation between SLC1A5 expression and hypoxia, angiogenesis and immune infiltration was analyzed and verified by immunohistochemistry, immunofluorescence and transcriptome sequencing. Liver cancer cell lines with SLC1A5 expression knockdown or overexpression were constructed, and cell proliferation, colony formation, apoptosis, migration and drug sensitivity as well as in vivo xenograft tumor were measured. A gene set enrichment analysis was conducted to determine the signaling pathway influenced by SLC1A5, and a western blot analysis was performed to detect protein expression alterations. RESULTS: SLC1A5 expression was higher in HCC tissue and associated with poor survival and TACE resistance. Hypoxia could stimulate the upregulation of glutamine transport, angiogenesis and SLC1A5 expression. The SLC1A5 expression was positively correlated with hypoxia and angiogenesis-related genes, immune checkpoint pathways, macrophage, Tregs, and other immunosuppressive cells infiltration. Knockdown of SLC1A5 decreased proliferation, colony formation, and migration, but increased apoptosis and increased sensitivity to chemotherapy drugs. Downregulation of SLC1A5 resulted in a decrease in Vimentin and N-cadherin expression, yet an increase in E-cadherin expression. Upregulation of SLC1A5 increased Vimentin and N-cadherin expression, while decreasing E-cadherin. Overexpression of ß-catenin in SLC1A5-knockdown HCC cell lines could augment Vimentin and N-cadherin expression, suppress E-cadherin expression, and increase the migration and drug resistance. CONCLUSIONS: Elevated SLC1A5 was linked to TACE resistance and survival shortening in HCC patients. SLC1A5 was positively correlated with hypoxia, angiogenesis, and immunosuppression. SLC1A5 may mediate HCC cell migration and drug resistance via Epithelial-mesenchymal transition (EMT) pathway.

Perfusion of hepatocellular carcinomas measured by diffusion-derived vessel density biomarker: Higher hepatocellular carcinoma perfusion than earlier intravoxel incoherent motion reports.

Diffusion-derived vessel density (DVDD) is a physiological surrogate of the area of microvessels per unit tissue area. DDVD is calculated according to DDVD(b0b2) = Sb0/ROIarea0 - Sb2/ROIarea2, where Sb0 and Sb2 refer to the liver signal when b is 0 or 2 s/mm2. Pathohistological studies and contrast-enhanced CT/MRI data showed higher blood volume in hepatocellular carcinoma (HCC) relative to native liver tissue. With intravoxel incoherent motion (IVIM) imaging, most authors paradoxically reported a decreased perfusion fraction of HCC relative to the adjacent liver. This study applied DDVD to assess the perfusion of HCC. MRI was performed with a 3.0-T magnet. Diffusion-weighted images with b-values of 0 and 2 s/mm2 were acquired in 72 HCC patients. Thirty-two patients had microvascular invasion (MVI(+)) and 40 patients did not have microvascular invasion (MVI(-)). Fifty-eight patients had Edmondson-Steiner grade I or II HCC, and 14 patients had Edmondson-Steiner grade III or IV HCC. DDVD measurement was conducted on the axial slice that showed the largest HCC size. DDVD(b0b2) T/L = HCC DDVD(b0b2)/liver DDVD(b0b2). DDVD(b0b2) T/L median (95% confidence interval) of all HCCs was 2.942 (2.419-3.522), of MVI(-) HCCs was 2.699 (2.030-3.522), of MVI(+) HCCs was 2.988 (2.423-3.990), of Edmondson-Steiner grade I/II HCCs was 2.873 (2.277-3.465), and of Edmondson-Steiner grade III/IV HCCs was 3.403 (2.008-4.485). DDVD(b0b2) T/L approximately agrees with contrast agent dynamically enhanced CT/MRI literature data, whereas it differs from earlier IVIM study results, where HCC perfusion fraction was paradoxically lower relative to native liver tissue. A weak trend was noted with MIV(+) HCCs had a higher DDVD(b0b2) T/L than that of MVI(-) HCCs, and a weak trend was noted with the poorly differentiated group of HCCs (Edmondson-Steiner grade III and IV) had a higher DDVD(b0b2) T/L than that of the better differentiated group of HCCs (Edmondson-Steiner grade I and II).

Comparison of contrast-enhanced ultrasonography and MRI results obtained by expert and novice radiologists indicating short-term response after transarterial chemoembolisation for hepatocellular carcinoma.

AIM: To evaluate inter-reader agreement between novice and expert radiologists in assessing contrast-enhanced ultrasonography (CEUS) and magnetic resonance imaging (MRI) images for detecting viable tumours with different sizes after conventional transarterial chemoembolisation (cTACE). MATERIALS AND METHODS: This prospective study included patients who had less than five hepatomas and who underwent cTACE. Hepatomas with one or two feeding arteries were selected as target lesions. CEUS and MRI were performed within 1 week after cTACE to evaluate viable tumours. RESULTS: The expert group had higher kappa values in evaluating all tumour sizes via CEUS compared with MRI. The novice group had similar kappa values. In patients with tumours measuring ≤3 cm, the expert group had higher kappa values in reading CEUS compared with MRI images; however, in the novice group, the kappa value was lower in evaluating CEUS compared with MRI images. In patients with tumours measuring >3 cm, the expert and novice groups had good to excellent kappa values. The confidence level of the two groups in reading MRI images was high; however, the novice group had a lower confidence level. CONCLUSION: CEUS is a convenient, cost-effective, and easy to apply imaging tool that can help interventionists perform early detection of viable hepatocellular carcinoma post-TACE. It has a higher inter-rater agreement in interpreting CEUS images compared with MRI images among expert radiologists even when they are extremely familiar with post-cTACE MRI images. In novice radiologists, there may be a learning curve to achieve good consistency in CEUS interpretation.

Preoperative evaluation of microvascular invasion in hepatocellular carcinoma with a radiological feature-based nomogram: a bi-centre study.

PURPOSE: To develop a nomogram for preoperative assessment of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) based on the radiological features of enhanced CT and to verify two imaging techniques (CT and MRI) in an external centre. METHOD: A total of 346 patients were retrospectively included (training, n = 185, CT images; external testing 1, n = 90, CT images; external testing 2, n = 71, MRI images), including 229 MVI-negative patients and 117 MVI-positive patients. The radiological features and clinical information of enhanced CT images were analysed, and the independent variables associated with MVI in HCC were determined by logistic regression analysis. Then, a nomogram prediction model was constructed. External validation was performed on CT (n = 90) and MRI (n = 71) images from another centre. RESULTS: Among the 23 radiological and clinical features, size, arterial peritumoral enhancement (APE), tumour margin and alpha-fetoprotein (AFP) were independent influencing factors for MVI in HCC. The nomogram integrating these risk factors had a good predictive effect, with AUC, specificity and sensitivity values of 0.834 (95% CI: 0.774-0.895), 75.0% and 83.5%, respectively. The AUC values of external verification based on CT and MRI image data were 0.794 (95% CI: 0.700-0.888) and 0.883 (95% CI: 0.807-0.959), respectively. No statistical difference in AUC values among training set and testing sets was found. CONCLUSION: The proposed nomogram prediction model for MVI in HCC has high accuracy, can be used with different imaging techniques, and has good clinical applicability.

Preoperative Contrast-Enhanced Ultrasound Predicts Microvascular Invasion in Hepatocellular Carcinoma as Accurately as Contrast-Enhanced MR.

OBJECTIVES: Both contrast-enhanced ultrasound (CEUS) and contrast-enhanced magnetic resonance (CEMR) are important imaging methods for hepatocellular carcinoma (HCC). This study aimed to establish a model using preoperative CEUS parameters to predict microvascular invasion (MVI) in HCC, and compare its predictive efficiency with that of CEMR model. METHODS: A total of 93 patients with HCC (39 cases in MVI positive group and 54 cases in MVI negative group) who underwent surgery in our hospital from January 2020 to June 2021 were retrospectively analyzed. Their clinical and imaging data were collected to establish CEUS and CEMR models for predicting MVI. The predictive efficiencies of both models were compared. RESULTS: By the univariate and multivariate regression analyses of patients' clinical information, preoperative CEUS static and dynamic images, we found that serrated edge and time to peak were independent predictors of MVI. The CEUS prediction model achieved a sensitivity of 92.3%, a specificity of 83.3%, and an accuracy of 84.6% (Az: 0.934). By analyzing the clinical and CEMR information, we found that tumor morphology, fast-in and fast-out, peritumoral enhancement, and capsule were independent predictors of MVI. The CEMR prediction model achieved a sensitivity of 97.4%, a specificity of 77.8%, and an accuracy of 83.2% (Az: 0.900). The combination of the two models achieved a sensitivity of 84.6%, a specificity of 87.0%, and an accuracy of 86.2% (Az: 0.884). There was no significant statistical difference in the areas under the ROC curve of the three models. CONCLUSION: The CEUS model and the CEMR model have similar predictive efficiencies for MVI of HCC. CEUS is also an effective method to predict MVI before operation.

20(S)-Ginsenoside Rh2 inhibits hepatocellular carcinoma by suppressing angiogenesis and the GPC3-mediated Wnt/ß­catenin signaling pathway.

20(S)-Ginsenoside Rh2 has significant anti-tumor effects in various types of cancers, including human hepatocellular carcinoma (HCC). However, its molecular targets and mechanisms of action remain largely unknown. Here, we aim to elucidate the potential mechanisms by which Rh2 suppresses HCC growth. We first demonstrate the role of Rh2 in inhibiting angiogenesis. We observe that Rh2 effectively suppresses cell proliferation and induces apoptosis in HUVECs. Furthermore, Rh2 significantly inhibits HepG2-stimulated HUVEC proliferation, migration and tube formation, accompanied by the downregulation of VEGF and MMP-2 expressions. We also reveal that Rh2 inhibits HCC growth through the downregulation of glypican-3-mediated activation of the Wnt/ß-catenin pathway. We observe a dose-dependent inhibition of proliferation and induction of apoptosis in HepG2 cells upon Rh2 treatment, which is mediated by the inhibition of glypican-3/Wnt/ß-catenin signaling. Moreover, downregulation of glypican-3 expression enhances the effects of Rh2 on the glypican-3/Wnt/ß-catenin signaling pathway, resulting in greater suppression of tumor growth in HepG2 cells. Collectively, our findings shed light on the molecular mechanisms through which Rh2 modulates HCC growth, which involve the regulation of angiogenesis and the glypican-3/Wnt/ß-catenin pathway. These insights may pave the way for the development of novel therapeutic strategies targeting these pathways for the treatment of HCC.

Two-dimensional perfusion angiography permits direct visualization of redistribution of flow in hepatocellular carcinoma during b-TACE.

OBJECTIVES: To demonstrate in vivo redistribution of the blood flow towards HCC's lesions by utilizing two-dimensional perfusion angiography in b-TACE procedures. MATERIAL AND METHODS: In total, 30 patients with 35 HCC nodules treated in the period between January 2019 and November 2021. For each patient, a post-processing software leading to a two-dimensional perfusion angiography was applied on each angiography performed via balloon microcatheter, before and after inflation. On the colour map obtained, reflecting the evolution of contrast intensity change over time, five regions of interests (ROIs) were assessed: one on the tumour (ROI-t), two in the immediate peritumoural healthy liver parenchyma (ROI-ihl) and two in the peripheral healthy liver parenchyma (ROI-phl). The results have been interpreted with a novel in silico model that simulates the hemodynamics of the hepatic arterial system. RESULTS: Among the ROIs drawn inside the same segment of target lesion, the time-to-peak of the ROI-t and of the ROI-ihl have a significantly higher mean value when the balloon was inflated compared with the ROIs obtained with deflated balloon (10.33 ± 3.66 s vs 8.87 ± 2.60 s (p = 0.015) for ROI-t; 10.50 ± 3.65 s vs 9.23 ± 2.70 s (p = 0.047) for ROI-ihl). The in silico model prediction time-to-peak delays when balloon was inflated, match with those observed in vivo. The numerical flow analysis shows how time-to-peak delays are caused by the obstruction of the balloon-occluded artery and the opening of intra-hepatic collateral. CONCLUSION: The measurements identify predictively the flow redistribution in the hepatic arteries during b-TACE, supporting a proper positioning of the balloon microcatheter.

[The influence of knocking down the expression of low-density lipoprotein receptor associated proteins on the vascular abnormalities in hepatocellular carcinoma and its mechanisms].

Objectives: To investigate the effect of the expression of low-density lipoprotein receptor associated protein (LDLR) on the vascular abnormalities in hepatocellular carcinoma (HCC) and its mechanisms. Methods: Based on the information of Oncomine Cancer GeneChip database, we analyzed the correlation between the expression level of LDLR and the expression level of carcinoembryonic antigen (CEA) and CD31 in hepatocellular carcinoma tissues. Lentiviral transfection of short hairpin RNA target genes was used to construct LDLR-knockdown MHCC-97H and HLE hepatocellular carcinoma cells. The differential genes and their expression level changes in LDLR-knockdown hepatocellular carcinoma cells were detected by transcriptome sequencing, real-time fluorescence quantitative polymerase chain reaction, and protein immunoblotting. The gene-related signaling pathways that involve LDLR were clarified by enrichment analysis. The effect of LDLR on CEA was assessed by the detection of CEA content in conditioned medium of hepatocellular carcinoma cells. Angiogenesis assay was used to detect the effect of LDLR on the angiogenic capacity of human umbilical vein endothelial cells, as well as the role of CEA in the regulation of angiogenesis by LDLR. Immunohistochemical staining was used to detect the expression levels of LDLR in 176 hepatocellular carcinoma tissues, and CEA and CD31 in 146 hepatocellular carcinoma tissues, and analyze the correlations between the expression levels of LDLR, CEA, and CD31 in the tissues, serum CEA, and alanine transaminase (ALT). Results: Oncomine database analysis showed that the expressions of LDLR and CEA in the tissues of hepatocellular carcinoma patients with portal vein metastasis were negatively correlated (r=-0.64, P=0.001), whereas the expressions of CEA and CD31 in these tissues were positively correlated ( r=0.46, P=0.010). The transcriptome sequencing results showed that there were a total of 1 032 differentially expressed genes in the LDLR-knockdown group and the control group of MHCC-97H cells, of which 517 genes were up-regulated and 515 genes were down-regulated. The transcript expression level of CEACAM5 was significantly up-regulated in the cells of the LDLR-knockdown group. The Gene Ontology (GO) function enrichment analysis showed that the differential genes were most obviously enriched in the angiogenesis function. The Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analysis showed that the relevant pathways involved mainly included the cellular adhesion patch, the extracellular matrix receptor interactions, and the interactions with the extracellular matrix receptors. The CEA content in the conditioned medium of the LDLR-knockdown group was 43.75±8.43, which was higher than that of the control group (1.15±0.14, P＜0.001). The results of angiogenesis experiments showed that at 5 h, the number of main junctions, the number of main segments, and the total area of the lattice formed by HUVEC cells cultured with the conditioned medium of MHCC-97H cells in the LDLR-knockdown group were 295.3±26.4, 552.5±63.8, and 2 239 781.0±13 8211.9 square pixels, which were higher than those of the control group (113.3±23.5, 194.8±36.5, and 660 621.0±280 328.3 square pixels, respectively, all P＜0.01).The number of vascular major junctions, the number of major segments, and the total area of the lattice formed by HUVEC cells cultured in conditioned medium with HLE cells in the LDLR-knockdown group were 245.3±42.4, 257.5±20.4, and 2 535 754.5±249 094.2 square pixels, respectively, which were all higher than those of the control group (113.3±23.5, 114.3±12.2, and 1 565 456.5±219 259.7 square pixels, respectively, all P＜0.01). In the conditioned medium for the control group of MHCC-97H cells,the number of main junctions, the number of main segments, and the total area of the lattice formed by the addition of CEA to cultured HUVEC cells were 178.9±12.0, 286.9±12.3, and 1 966 990.0±126 249.5 spixels, which were higher than those in the control group (119.7±22.1, 202.7±33.7, and 1 421 191.0±189 837.8 square pixels, respectively). The expression of LDLR in hepatocellular carcinoma tissues was not correlated with the expression of CEA, but was negatively correlated with the expression of CD31 (r=-0.167, P=0.044), the level of serum CEA (r=-0.061, P=0.032), and the level of serum ALT(r=-0.147,P=0.05). The expression of CEA in hepatocellular carcinoma tissues was positively correlated with the expression of CD31 (r=0.192, P=0.020). The level of serum CEA was positively correlated with the level of serum ALT (r=0.164, P=0.029). Conclusion: Knocking down LDLR can promote vascular abnormalities in HCC by releasing CEA.

Comparison of preoperative ultrasound and MRI in the diagnosis of microvascular invasion in hepatocellular carcinoma.

Ultrasound has few reports on its application in prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC). The purpose of this study was to explore the diagnostic efficacies of preoperative ultrasound and magnetic resonance imaging (MRI) for HCC MVI and compare these two imaging methods for the diagnosis of this condition. The clinical and preoperative ultrasound and MR imaging data of 26 patients with newly diagnosed HCC were collected between October 2020 and October 2021. According to the gold standard (postoperative pathology), the patients were divided into MVI-positive and MVI-negative groups, and the efficacies of ultrasound and MRI in diagnosing HCC MVI and the consistency between the two imaging modalities were analyzed. For the preoperative diagnosis of MVI using ultrasound, the sensitivity was 93.33%, the specificity was 81.82%, and the accuracy was 88.46%. For preoperative MRI, the sensitivity was 66.67%, the specificity was 100%, and the accuracy was 80.77%. In diagnosing MVI, the two methods had significantly different efficacy (P = 0.031). Ultrasound and MRI have high diagnostic efficiency for MVI, but the accuracy of preoperative MRI was lower than that of preoperative ultrasound. These results indicate that ultrasound has a certain guiding significance in the diagnosis of HCC MVI.

Hepatocellular Carcinoma Supplied by the Inferior Phrenic Artery or Cystic Artery: Anatomic and Technical Considerations.

Intra-arterial treatment has been identified as one of the mainstays in the management of unresectable hepatocellular carcinoma. A thorough knowledge of tumor arterial supply enables selective therapy, which improves both safety and efficacy. The inferior phrenic artery (IPA) is the most common extrahepatic collateral artery that feeds hepatocellular carcinoma. The bilateral IPAs are known to have a specific vascular anatomy. A systemic-to-pulmonary shunt and a gastric branch from the IPAs may be present and should not be confused with tumor blush. The supraceliac aorta and celiac trunk are the common origin sites of the IPAs, and their orifice may be compressed by the diaphragm. Various techniques and catheters are used for catheterization of the IPAs, depending on their origin sites. Because the IPA is normally connected with the intercostal, internal mammary, retroperitoneal, and hepatic arteries, its hemodynamics may be altered when its orifice is occluded. In general, superselective chemoembolization via the target branch of the IPA is safe and effective. When a systemic-to-pulmonary shunt from the IPA is adequately embolized with coils or particles, radioembolization through the IPA can be performed safely in most cases. The cystic artery branches into deep and superficial cystic arteries; deep cystic arteries often supply tumors near the gallbladder. Chemoembolization through the cystic artery is relatively safe, with transient embolic materials. Radioembolization through the cystic artery has been recently tried, with acceptable efficacy and toxicity results, but it requires further investigation. ©RSNA, 2022.

Inhibition of Hepatic Stellate Cell Activation Suppresses Tumorigenicity of Hepatocellular Carcinoma in Mice.

Transdifferentiation (or activation) of hepatic stellate cells (HSCs) to myofibroblasts is a key event in liver fibrosis. Activated HSCs in the tumor microenvironment reportedly promote tumor progression. This study analyzed the effect of an inhibitor of HSC activation, retinol-binding protein-albumin domain III fusion protein (R-III), on protumorigenic functions of HSCs. Although conditioned medium collected from activated HSCs enhanced the migration, invasion, and proliferation of the hepatocellular carcinoma cell line Hepa-1c1c7, this effect was not observed in Hepa-1c1c7 cells treated with conditioned medium from R-III-exposed HSCs. In a subcutaneous tumor model, larger tumors with increased vascular density were formed in mice transplanted with Hepa-1c1c7+HSC than in mice transplanted with Hepa-1c1c7 cells alone. Intriguingly, when Hepa-1c1c7+HSC-transplanted mice were injected intravenously with R-III, a reduction in vascular density and extended tumor necrosis were observed. In an orthotopic tumor model, co-transplantation of HSCs enhanced tumor growth, angiogenesis, and regional metastasis accompanied by increased peritumoral lymphatic vessel density, which was abolished by R-III. In vitro study showed that R-III treatment affected the synthesis of pro-angiogenic and anti-angiogenic factors in activated HSCs, which might be the potential mechanism underlying the R-III effect. These findings suggest that the inhibition of HSC activation abrogates HSC-induced tumor angiogenesis and growth, which represents an attractive therapeutic strategy.

Analysis and Validation of Human Targets and Treatments Using a Hepatocellular Carcinoma-Immune Humanized Mouse Model.

BACKGROUND AND AIMS: Recent development of multiple treatments for human hepatocellular carcinoma (HCC) has allowed for the selection of combination therapy to enhance the effectiveness of monotherapy. Optimal selection of therapies is based on both HCC and its microenvironment. Therefore, it is critical to develop and validate preclinical animal models for testing clinical therapeutic solutions. APPROACH AND RESULTS: We established cell line-based or patient-derived xenograft-based humanized-immune-system mouse models with subcutaneous and orthotopic HCC. Mice were injected with human-specific antibodies (Abs) to deplete human immune cells. We analyzed the transcription profiles of HCC cells and human immune cells by using real-time PCR and RNA sequencing. The protein level of HCC tumor cells/tissues or human immune cells was determined by using flow cytometry, western blotting, and immunohistochemistry. The HCC tumor size was measured after single, dual-combination, and triple-combination treatment using N-(1',2-Dihydroxy-1,2'-binaphthalen-4'-yl)-4-methoxybenzenesulfonamide (C188-9), bevacizumab, and pembrolizumab. In this study, human immune cells in the tumor microenvironment were strongly selected and modulated by HCC, which promoted the activation of the IL-6/Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in tumor cells and led to augmented HCC proliferation and angiogenesis by releasing angiogenic cytokines in humanized-immune-system mice with HCC. In particular, intratumor human cluster of differentiation-positive (hCD14+ ) cells could produce IL-33 through damage-associated molecular pattern/Toll-like receptor 4/activator protein 1, which up-regulated IL-6 in other intratumor immune cells and activated the JAK2/STAT3 pathway in HCC. Specific knockdown of the CD14 gene in human monocytes could impair IL-33 production induced by cell lysates. Subsequently, we evaluated the in vivo anti-HCC effect of C188-9, bevacizumab, and pembrolizumab. The results showed that the anti-HCC effect of triple-combination therapy was superior to that of single or dual treatments. CONCLUSIONS: Humanized-immune-system HCC mouse models are suitable for identifying targets from cancer and immune components and for testing combinational therapies.

Pharmacokinetic analysis of different contrast agents on multiphase enhanced MRI for microvascular invasion: preoperative prediction in hepatocellular carcinoma.

BACKGROUND: The preoperative diagnosis of microvascular invasion (MVI) for the solitary small hepatocellular carcinoma (sHCC) is crucial for the decision of surgical strategies. PURPOSE: To compare the kinetic parameters and diagnostic effects of two contrast agents for preoperatively predicting MVI of sHCC on multiphase enhanced magnetic resonance imaging (MRI). MATERIAL AND METHODS: Two groups of patients with known solitary sHCC underwent an enhanced MRI examination before hepatic resection: Data A (n = 61) patients underwent Gd-EOB-DTPA-enhanced MRI, and Data B (n = 41) patients had a normal contrast agent. The two sets of data were processed in the same way. Arterial peritumoral enhancement measured from multiphase enhanced MRI was analyzed using quantitative kinetic parameters, including initial signal enhancement (SE1), peak signal enhancement (SEpeak), and calculation of the signal enhancement ratio (SER). RESULTS: The statistical analysis showed that the average SE1 and SER (Data A) for the MVI-positive group were significantly higher (P < 0.05) than those in the MVI-negative group. The SER (Data B) and SEpeak showed no significant difference for either group. In Data A, the receiver operating characteristic analysis between the two groups had an area under the curve of 0.74 and 0.71 for SE1 and SER, respectively, which was higher than that of Data B. The different contrast agents had the same enhancement curve trend. CONCLUSION: Gd-EOB-DTPA-enhanced MRI had a better quantitative kinetic parameter analysis effect for arterial peritumoral enhancement on predicting MVI of sHCC in clinical practice.

BMP9-ID1 Signaling Activates HIF-1α and VEGFA Expression to Promote Tumor Angiogenesis in Hepatocellular Carcinoma.

Since hepatocellular carcinoma (HCC) is a typical hypervascular malignant tumor with poor prognosis, targeting angiogenesis is an important therapeutic strategy for advanced HCC. Involvement of bone morphologic protein 9 (BMP9), a transforming growth factor-beta superfamily member, has recently been reported in the development of liver diseases and angiogenesis. Here, we aimed to elucidate the role of BMP9 signaling in promoting HCC angiogenesis and to assess the antiangiogenic effect of BMP receptor inhibitors in HCC. By analyzing HCC tissue gene expression profiles, we found that BMP9 expression was significantly correlated with angiogenesis-associated genes, including HIF-1α and VEGFR2. In vitro, BMP9 induced HCC cell HIF-1α/VEGFA expression and VEGFA secretion. Silencing of the inhibitor of DNA-binding protein 1 (ID1), a transcription factor targeted by BMP9 signaling, suppressed BMP9-induced HIF-1α/VEGFA expression and VEGFA secretion, resulting in decreased human umbilical vein endothelial cell (HUVEC) lumen formation. BMP receptor inhibitors, which inhibit BMP9-ID1 signaling, suppressed BMP9-induced HIF-1α/VEGFA expression, VEGFA secretion, and HUVEC lumen formation. In vivo, the BMP receptor inhibitor LDN-212854 successfully inhibited HCC tumor growth and angiogenesis by inhibiting BMP9-ID1 signaling. In summary, BMP9-ID1 signaling promotes HCC angiogenesis by activating HIF-1α/VEGFA expression. Thus, targeting BMP9-ID1 signaling could be a pivotal therapeutic option for advanced HCC.

The transcription factor ZFHX3 is crucial for the angiogenic function of hypoxia-inducible factor 1α in liver cancer cells.

Angiogenesis is a hallmark of tumorigenesis, and hepatocellular carcinoma (HCC) is hypervascular and therefore very dependent on angiogenesis for tumor development and progression. Findings from previous studies suggest that in HCC cells, hypoxia-induced factor 1α (HIF1A) and zinc finger homeobox 3 (ZFHX3) transcription factors functionally interact in the regulation of genes in HCC cells. Here, we report that hypoxia increases the transcription of the ZFHX3 gene and enhances the binding of HIF1A to the ZFHX3 promoter in the HCC cell lines HepG2 and Huh-7. Moreover, ZFHX3, in turn, physically associated with and was functionally indispensable for HIF1A to exert its angiogenic activity, as indicated by in vitro migration and tube formation assays of human umbilical vein endothelial cells (HUVECs) and microvessel formation in xenograft tumors of HCC cells. Mechanistically, ZFHX3 was required for HIF1A to transcriptionally activate the vascular endothelial growth factor A (VEGFA) gene by binding to its promoter. Functionally, down-regulation of ZFHX3 in HCC cells slowed their tumor growth, and addition of VEGFA to conditioned medium from ZFHX3-silenced HCC cells partially rescued the inhibitory effect of this medium on HUVEC tube formation. In human HCC, ZFHX3 expression was up-regulated, and this up-regulation correlated with both HIF1A up-regulation and worse patient survival, confirming a functional association between ZFHX3 and HIF1A in human HCC. We conclude that ZFHX3 is an angiogenic transcription factor that is integral to the HIF1A/VEGFA signaling axis in HCC cells.

Upregulation of Nogo-B by hypoxia inducible factor-1 and activator protein-1 in hepatocellular carcinoma.

Nogo-B is an important regulator of tumor angiogenesis. Expression of Nogo-B is remarkably upregulated in multiple tumor types, especially hepatocellular carcinoma (HCC). Here, we show the transcriptional regulation mechanisms of Nogo-B in liver cancer. In response to hypoxia, expression of Nogo-B significantly increased in HCC tissues and cells. The distal hypoxia-responsive element in the promoter was essential for transcriptional activation of Nogo-B under hypoxic conditions, which is the specific site for hypoxia inducible factor-1α (HIF-1α) binding. In addition, Nogo-B expression was associated with c-Fos expression in HCC tissues. Nogo-B expression was induced by c-Fos, yet inhibited by a dominant negative mutant A-Fos. Deletion and mutation analysis of the predicted activator protein-1 binding sites revealed that functional element mediated the induction of Nogo-B promoter activity, which was confirmed by ChIP. These results indicate that HIF-1α and c-Fos induce the expression of Nogo-B depending on tumor microenvironments, such as hypoxia and low levels of nutrients, and play a role in upregulation of Nogo-B in tumor angiogenesis.

RNA m6A methylation promotes the formation of vasculogenic mimicry in hepatocellular carcinoma via Hippo pathway.

Vasculogenic mimicry (VM) formed by aggressive tumor cells to mimic vasculogenic networks plays an important role in the tumor malignancy of HCC. However, the pathogenesis underlying VM is complex and has not been fully defined. m6A is a common mRNA modification and has many biological effects. However, the relationship between m6A and VM remains unclear. In this research, we found that m6A methyltransferase METTL3 in HCC tissues was positively correlated with VM. The m6A level of mRNA significantly increased in 3D cultured cells treated with VEGFa and was related to VM formation. Transcriptome sequencing analysis of 3D cultured cells with knockdown Mettl3 showed that the Hippo pathway was involved in m6A-mediated VM formation. Further mechanism research indicated that the m6A modification of YAP1 mRNA affected the translation of YAP1 mRNA. In conclusion, m6A methylation plays a key role in VM formation in HCC. METTL3 and YAP1 could be potential therapeutic targets via impairing VM formation in anti-metastatic strategies.

Gadoxetic acid-enhanced MRI of macrotrabecular-massive hepatocellular carcinoma and its prognostic implications.

BACKGROUND & AIMS: Despite the clinical and genetic significance of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC), its characteristics on imaging have not been described. This study aimed to characterise MTM-HCC on gadoxetic acid-enhanced MRI and to evaluate the diagnostic accuracy and prognostic value of these imaging characteristics. METHODS: We enrolled 3 independent cohorts from 2 tertiary care centres. The 3 cohorts consisted of a total of 476 patients who underwent gadoxetic acid-enhanced MRI and surgical resection for treatment-naïve single HCCs. Independent review of histopathology and MRI by 2 reviewers was performed for each cohort, and inter-reader agreement was evaluated. Based on the result of MRI review in the training cohort (cohort 1), we developed 2 diagnostic criteria for MTM-HCC and evaluated their prognostic significance. The diagnostic performance and prognostic significance were validated in 2 validation cohorts (cohorts 2 and 3). RESULTS: We developed 2 diagnostic MRI criteria (MRIC) for MTM-HCC: MRIC-1, ≥20% arterial phase hypovascular component; MRIC-2, ≥50% hypovascular component and 2 or more ancillary findings (intratumoural artery, arterial phase peritumoural enhancement, and non-smooth tumour margin). MRIC-1 showed high sensitivity and negative predictive value (88% and 95% in the training cohort, and 88% and 97% in the pooled validation cohorts, respectively), whereas MRIC-2 demonstrated moderate sensitivity and high specificity (47% and 94% in the training cohort, and 46% and 96% in the pooled validation cohorts, respectively). MRIC-2 was an independent poor prognostic factor for overall survival in both training and pooled validation cohorts. CONCLUSIONS: Using gadoxetic acid-enhanced MRI findings, including an arterial phase hypovascular component, we could stratify the probability of MTM-HCC and non-invasively obtain prognostic information. LAY SUMMARY: Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a histopathologic subtype of HCC characterised by aggressive biological behaviour and poor prognosis. We developed imaging criteria based on liver MRI that could be used for the non-invasive diagnosis of MTM-HCC. HCCs showing imaging findings of MTM-HCC were associated with poor outcomes after hepatic resection.

Regorafenib inhibits migration, invasion, and vasculogenic mimicry of hepatocellular carcinoma via targeting ID1-mediated EMT.

Regorafenib is approved for patients with unresectable hepatocellular carcinoma (HCC) following sorafenib. However, the effect of regorafenib on HCC metastasis and its mechanism are poorly understood. Here, our data showed that regorafenib significantly restrained the migration, invasion and vasculogenic mimicry (VM) of HCC cells, and downregulated the expression of epithelial-to-mesenchymal transition (EMT)/VM-related molecules. Using RNA-seq and cellular thermal shift assays, we found that inhibitor of differentiation 1 (ID1) was a key target of regorafenib. In HCC tissues, the protein expression of ID1 was positively correlated with EMT and VM formation (CD34- /PAS+ ). Functionally, ID1 knockdown inhibited HCC cell migration, invasion, metastasis, and VM formation in vitro and in vivo, with upregulation of E-cadherin and downregulation of Snail and VE-cadherin. Moreover, Snail overexpression promoted the migration, invasion, and VM formation of ID1 knockdown cells. Snail knockdown reduced the migration, invasion, and VM formation of ID1 overexpression cells. Finally, regorafenib suppressed VM formation and decreased the expression of ID1, VE-cadherin and Snail in HCC PDX model. In conclusion, we manifested that regorafenib distinctly inhibited EMT in HCC cells via targeting ID1, leading to the suppression of cell migration, invasion and VM formation. These findings suggest that regorafenib may be developed as a suitable therapeutic agent for HCC metastasis.