Molecular Imaging of Tumor Microenvironment to Assess the Effects of Locoregional Treatment for Hepatocellular Carcinoma

Assessment of viable tumours by [68Ga]Ga-FAPI-04 PET/CT after local regional treatment in patients with hepatocellular carcinoma

PURPOSE

To investigate the efficacy of [68Ga]Ga-FAPI-04 PET/CT for assessing viable tumours (VTs) after local regional treatment (LRT) in hepatocellular carcinoma (HCC) patients. The related imaging features of HCC after LRT are preliminarily discussed.

METHODS

A cohort of 37 LRT patients with HCC (encompassing 51 lesions) was retrospectively included from a prospective parent study (ChiCTR2000039099), and sequential PET/CT using [18F]FDG and [68Ga]Ga-FAPI-04 was performed. The diagnostic accuracies of [68Ga]Ga-FAPI-04 and [18F]FDG PET/CT and multiphasic CT/MRI for detecting VTs after LRT were calculated and analysed. Pathological examination was considered the gold standard for VT diagnosis, and clinical follow-up was used as the reference standard. The SUVmax and tumour-to-background ratio (TBR) derived from [18F]FDG and [68Ga]Ga-FAPI-04 PET/CT were calculated and compared. Moreover, the SUVmax, target-to-normal liver ratio (TNR) of VT, tumour necrosis (TN), benign rim (BR), and normal liver (NL) from different imaging modalities after LRT for HCC were compared.

RESULTS

Both the sensitivity (96.0% [24/25] vs. 36.0% [9/25], p < 0.001) and accuracy (94.1%, [48/51] vs. 68.6% [35/51], p = 0.004) of [68Ga]Ga-FAPI-04 PET/CT for detecting VTs after LRT were greater than those of [18F]FDG PET/CT, whereas their specificities were comparable (92.3% [24/26] vs. 100% [26/26]). Notably, [68Ga]Ga-FAPI-04 PET/CT had a greater SUVmax (9.80 vs. 3.60) and TBR (9.93 vs. 1.57) than [18F]FDG PET/CT in VT patients (all p < 0.001). Furthermore, VT had a greater SUVmax and TNR than did TN, BR, and NL on [68Ga]Ga-FAPI-04 PET/CT (all p < 0.001) and exhibited morphologic nodular, mass-like, or irregular tracer uptake. Although no significant differences were observed for VT detection (all p > 0.05), [68Ga]Ga-FAPI-04 PET/CT and multiphasic CT/MRI complemented each other in some cases.

CONCLUSION

[68Ga]Ga-FAPI-04 PET/CT not only presented higher sensitivity and accuracy than [18F]FDG PET/CT for diagnosing VTs after LRT for HCC but also showed comparable diagnostic accuracy and complementary roles with multiphasic CT/MRI. Overall, [68Ga]Ga-FAPI-04 PET/CT may play an essential role in surveillance after LRT for HCC.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2000039099. Registered 17 October 2020.

Exploring the microRNA-mitochondrial nexus in hepatocellular carcinoma

MicroRNAs (miRNAs) are double-edged swords in hepatocellular carcinoma (HCC) that play a dual role in disease progression and suppression. The pivotal role of miRNAs in gene regulation emphasizes their potential to disrupt critical cellular processes, including mitochondrial function. Given the indispensable role of mitochondria in energy production, apoptosis, and metabolic control, all of which are central to HCC progression, understanding the miRNA-mitochondria axis is crucial. MiRNAs emerge as pivotal regulators of mitochondrial function, exerting profound influence over HCC progression. This comprehensive review delves into the multifaceted roles of miRNAs in modulating mitochondrial biogenesis, dynamics, and apoptosis. MiRNA impacts key metabolic pathways, including energy metabolism, fatty acid metabolism, and oxidative stress. The intricate interplay between miRNAs and mitochondrial function extends to the regulation of mitophagy and ferroptosis. By exploring the microRNA-mitochondrial axis, this review offers insights for identifying novel diagnostic and therapeutic targets.

Association of LR treatment response category with outcome of patients with hepatocellular carcinoma on explant pathology

OBJECTIVES

Liver transplant (LT) is an effective treatment for hepatocellular carcinoma (HCC) in appropriately selected patients. Locoregional therapy (LRT) is often performed to extend a patient's eligibility for LT. Imaging has a modest sensitivity of approximately 40-77% for detecting pathologically viable HCC in post-LRT patients. The impact on overall survival (OS) and disease-free survival (DFS) is unclear. We hypothesize that Liver Imaging Reporting & Data Systems Treatment Response (LI-RADS TR) category is equivalently correlated with long-term survival and overall disease-free progression when compared to explant pathology findings. We additionally hypothesize that neoadjuvant LRT can improve OS and DFS in LT patients initially within MC.

METHODS

Patients found to have HCC on explant between January 2005 and December 2021 were included. A total of 167 patients were divided into treatment (any pre-LT LRT except for Y-90 therapy) and control (no pre-LT LRT) groups. Of the patients who received pre-LT LRT, imaging studies were reviewed by two abdominal radiologists using 2018 LI-RADS criteria. Statistical analysis was performed using Kaplan-Meier survival curves and Cox proportional hazard models to assess OS and DFS.

RESULTS

No statistically significant difference in OS or DFS (p = 0.23 and p = 0.22 respectively) was initially found. Given significant difference in age between the groups (p < 0.0001), Cox proportional hazard models were used to adjust for age with statistical significance reached for better OS and DFS in the treatment group (p = 0.05 and p = 0.05 respectively). Contrary to our hypothesis, there was no difference between treatment response groups regarding overall survival or disease-free survival, presumably because of low number of HCC recurrences in our patient population (4%).

CONCLUSION

Despite not reaching statistical significance, LI-RADS TR categorization demonstrates a good interreader agreement (Kappa 0.6), helping radiologists feel comfortable that modest sensitivity of the LI-RADS TR treatment response category for detecting pathologically active malignancy does not confer a negative clinical outcome.

Interventional Oncology Meets Immuno-oncology: Combination Therapies for Hepatocellular Carcinoma

The management of hepatocellular carcinoma (HCC) is undergoing transformational changes due to the emergence of various novel immunotherapies and their combination with image-guided locoregional therapies. In this setting, immunotherapy is expected to become one of the standards of care in both neoadjuvant and adjuvant settings across all disease stages of HCC. Currently, more than 50 ongoing prospective clinical trials are investigating various end points for the combination of immunotherapy with both percutaneous and catheter-directed therapies. This review will outline essential tumor microenvironment mechanisms responsible for disease evolution and therapy resistance, discuss the rationale for combining locoregional therapy with immunotherapy, summarize ongoing clinical trials, and report on developing imaging end points and novel biomarkers that are relevant to both diagnostic and interventional radiologists participating in the management of HCC.

Radioiodine-131-Labeled Theranostic Nanoparticles for Transarterial Radioembolization and Chemoembolization Combination Therapy of VX2 Liver Tumor

In interventional treatment, materials are administered into the blood supply artery and directly delivered to tumors, offering proper scenarios for nanomedicine potential clinical applications. Transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) are effective treatment methods for hepatocellular carcinoma (HCC), but postoperative residual tumor may result in intrahepatic recurrence and distant metastasis. The combination therapy of TACE and TARE based on multifunctional nanoparticles (NPs) is expected to overcome the drug resistance in hypoxic tumors and improve the therapeutic effect. Herein, BaGdF5 NPs are synthesized and then coated with polydopamine (PDA), conjugated with the chemotherapeutic drug cis-diamminedichloride platinum (CDDP), radio-labeled with therapeutic radionuclide 131 I, yielding 131 I-BaGdF5 @PDA-CDDP NPs. The in vitro anti-cancer effects of 131 I-BaGdF5 @PDA-CDDP NPs are confirmed using CCK-8 and γ-H2AX assays in Huh7 cells. Mixed with Lipiodol, 131 I-BaGdF5 @PDA-CDDP NPs are injected into the hepatic artery via a microcatheter to realize the TACE and TARE combination therapy in a rabbit VX2 liver tumor model. The results indicate that glucose metabolism is clearly decreased based on 18 F-FDG PET imaging and the apoptosis of tumor cells is increased. Furthermore, 131 I and BaGdF5 NPs can be used for SPECT imaging and CT/MR imaging respectively, facilitating real-time monitoring of the in vivo biodistribution of 131 I-BaGdF5 @PDA-CDDP NPs.

Decreased B4GALT1 promotes hepatocellular carcinoma cell invasiveness by regulating the laminin-integrin pathway

Beta1,4-galactosyltransferases (B4GALTs) play a crucial role in several diseases, including cancer. B4GALT1 is highly expressed in the liver, and patients with mutations in B4GALT1 exhibit hepatopathy. However, the role of B4GALT1 in liver cancer remains unclear. Here, we found that B4GALT1 was significantly downregulated in hepatocellular carcinoma (HCC) tissue compared with the adjacent liver tissue, and low B4GALT1 expression was associated with vascular invasion and poor overall survival in patients with HCC. Additionally, silencing or loss of B4GALT1 enhanced HCC cell migration and invasion in vitro and promoted lung metastasis of HCC in NOD/SCID mice. Moreover, B4GALT1 knockdown or knockout increased cell adhesion to laminin, whereas B4GALT1 overexpression decreased the adhesion. Through a mass spectrometry-based approach and Griffonia simplicifolia lectin II (GSL-II) pull-down assays, we identified integrins α6 and β1 as the main protein substrates of B4GALT1 and their N-glycans were modified by B4GALT1. Further, the increased cell migration and invasion induced by B4GALT1 knockdown or knockout were significantly reversed using a blocking antibody against integrin α6 or integrin β1. These results suggest that B4GALT1 downregulation alters N-glycosylation and enhances the laminin-binding activity of integrin α6 and integrin β1 to promote invasiveness of HCC cells. Our findings provide novel insights into the role of B4GALT1 in HCC metastasis and highlight targeting the laminin-integrin axis as a potential therapeutic strategy for HCC with low B4GALT1 expression.

Hepatocellular Carcinoma cells: activity of Amygdalin and Sorafenib in Targeting AMPK /mTOR and BCL-2 for anti-angiogenesis and apoptosis cell death

BACKGROUND

Sorafenib (Sor) is the only approved multikinase inhibitor indicated for the treatment of HCC. Previous studies have shown that amygdalin (Amy) possesses anticancer activities against several cancer cell lines; we suggested that these compounds might disrupt AMPK/mTOR and BCL-2. Therefore, the current study used integrated in vitro and in silico approaches to figure out Amy and Sor's possible synergistic activity in targeting AMPK/mTOR and BCL-2 for anti-angiogenesis and apoptosis cell death in HepG2 cells.

RESULTS

Notably, Amy demonstrated exceptional cytotoxic selectivity against HepG2 cells in comparison to normal WI-38 cells (IC50 = 5.21 mg/ml; 141.25 mg/ml), respectively. In contrast, WI-38 cells were far more sensitive to the toxicity of Sor. A substantial synergistic interaction between Amy and Sor was observed (CI50 = 0.56), which was connected to cell cycle arrest at the S and G2/M stages and increased apoptosis and potential necroptosis. Amy and Sor cotreatment resulted in the highest glutathione levels and induction of pro-autophagic genes AMPK, HGMB1, ATG5, Beclin 1, and LC3, suppressed the mTOR and BCL2 anti-apoptotic gene. Finally, the docking studies proposed that Amy binds to the active site of the AMPK enzyme, thus inhibiting its activity. This inhibition of AMPK ultimately leads to inhibition of mTOR and thus induces apoptosis in the HepG2 cells.

CONCLUSION

Although more in vivo research using animal models is needed to confirm the findings, our findings contribute to the evidence supporting Amy's potential anticancer effectiveness as an alternative therapeutic option for HCC.

Recent Trends in Diagnostic Biomarkers of Tumor Microenvironment

The tumor microenvironment (TME) play critical roles in tumor survival, progression, and metastasis and can be considered potential targets for molecular imaging of cancer. The targeting agents for imaging of TME components (e.g., fibroblasts, mesenchymal stromal cells, immune cells, extracellular matrix, blood vessels) provide a promising strategy to target these biomarkers for the early diagnosis of cancers. Moreover, various cancer types have similar tumor immune microenvironment (TIME) features that targeting those biomarkers and offer clinically translatable molecular imaging of cancers. In this review, we categorize and summarize the components in TME which have been targeted for molecular imaging. Moreover, this review updated the recent progress in targeted imaging of TIME biological molecules by various modalities for the early detection of cancer.

Immune checkpoint and angiogenic inhibitors for the treatment of hepatocellular carcinoma: It takes two to tangle

Immunotherapy represents an effective and promising option in various cancers, including in hepatocellular carcinoma (HCC). The immune checkpoint inhibitors (ICIs) have shown a remarkable breakthrough in the last decade, in addition to molecular targeted therapy of angiogenesis such as tyrosine kinases inhibitors. ICIs provide new regimen that can be applied in different stages of the disease. In parallel, HCC progression is related to the tumor microenvironment (TME), involving the cross-talk between various cellular and non-cellular components within the TME niche. It appears logical to synergistically target several HCC components to increase the efficacy of the treatment. In this paper, we summarize evidence that the combination therapy of ICIs and angiogenesis inhibitors would be a potentially better strategy for HCC treatment.

Multiscale biomechanics and mechanotransduction from liver fibrosis to cancer

A growing body of multiscale biomechanical studies has been proposed to highlight the mechanical cues in the development of hepatic fibrosis and cancer. At the cellular level, changes in mechanical microenvironment induce phenotypic and functional alterations of hepatic cells, initiating a positive feedback loop that promotes liver fibrogenesis and hepatocarcinogenesis. Tumor mechanical microenvironment of hepatocellular carcinoma facilitates tumor cell growth and metastasis, and hinders the drug delivery and immunotherapy. At the molecular level, mechanical forces are sensed and transmitted into hepatic cells via allosteric activation of mechanoreceptors on the cell membrane, leading to the activation of various mechanotransduction pathways including integrin and YAP signaling and then regulating cell function. Thus, the application of mechanomedicine concept in the treatment of liver diseases is promising for rational design and cell-specific delivery of therapeutic drugs. This review mainly discusses the correlation between biomechanical cues and liver diseases from the viewpoint of mechanobiology.

Limitations of Fluorine 18 Fluoromisonidazole in Assessing Treatment-induced Tissue Hypoxia after Transcatheter Arterial Embolization of Hepatocellular Carcinoma: A Prospective Pilot Study

Purpose To determine the variance and correlation with tumor viability of fluorine 18 (¹⁸F) fluoromisonidazole (FMISO) uptake in hepatocellular carcinoma (HCC) prior to and after embolization treatment. Materials and Methods In this single-arm, single-center, prospective pilot study between September 2016 and March 2017, participants with at least one tumor measuring 1.5 cm or larger with imaging or histologic findings diagnostic for HCC were enrolled (five men; mean age, 68 years; age range, 61-76 years). Participants underwent ¹⁸F-FMISO PET/CT before and after bland embolization of HCC. A tumor-to-liver ratio (TLR) was calculated by using standardized uptake values of tumor and liver. The difference in mean TLR before and after treatment was compared by using a Wilcoxon rank sum test, and correlation between TLR and tumor viability was assessed by using the Spearman rank correlation coefficient. Results Four participants with five tumors were included in the final analysis. The median tumor diameter was 3.2 cm (IQR, 3.0-3.9 cm). The median TLR before treatment was 0.97 (IQR, 0.88-0.98), with a variance of 0.02, and the median TLR after treatment was 0.85 (IQR, 0.79-1), with a variance of 0.01; both findings indicate a narrow range of ¹⁸F-FMISO uptake in HCC. The Spearman rank correlation coefficient was 0.87, indicating a high correlation between change in TLR and nonviable tumor. Conclusion Although there was a correlation between change in TLR and response to treatment, the low signal-to-noise ratio of ¹⁸F-FMISO in the liver limited its use in HCC. Keywords: Molecular Imaging-Clinical Translation, Embolization, Abdomen/Gastrointestinal, Liver Clinical trial registration no. NCT02695628 © RSNA, 2022.

The Detection and Verification of Two Heterogeneous Subgroups and a Risk Model Based on Ferroptosis-Related Genes in Hepatocellular Carcinoma

^#Background. Because of the heterogeneity of hepatocellular carcinoma (HCC) and the complex nature of the tumor microenvironment (TME), the long-term efficacy of therapy continues to be a clinical challenge. It is necessary to classify and refine the appropriate treatment intervention decision-making in this kind of tumor. Methods. We used “ConsensusClusterPlus” to establish a stable molecular classification based on the ferroptosis-related genes (FRGs) expression obtained from FerrDb. The clinical features, immune infiltration, DNA damage, and genomic changes of different subclasses were evaluated. The least absolute shrinkage and selection operator regression (LASSO) method and univariate Cox regression were utilized to construct the ferroptosis-related prognosis risk score (FPRS) model, and the association between the FPRS model and HCC molecular characteristics, immune features, and immunotherapy was studied. Results. We identified two ferroptosis subclasses, C1 with poor prognosis and a higher proportion of patients in the middle and late stages infected with HBV and HCV, having higher DNA damage including aneuploidy, HRD, fraction altered, and the number of segments, and higher probability of gene mutation and copy number mutation. FPRS model was constructed on the basis of differentially expressed genes (DEGs) between C1 and C2, which showed a higher area under the curve (AUC) in predicting overall survival rate in the training set and independent verification cohort and could reflect the clinical characteristics and response to immunotherapy of different patients, being an independent prognostic factor of HCC. Conclusion. Here, we revealed two novel molecular subgroups based on FRGs and develop an FPRS model consisting of six genes that can help predict prognosis and select patients suitable for immunotherapy.