EpCAM and alpha-fetoprotein expression defines novel prognostic subtypes of hepatocellular carcinoma

Multi-omics analysis revealed the role of extracellular vesicles in hepatobiliary & pancreatic tumor

Liquid biopsy is rapidly growing into a hot research field due to its unique advantages of minimal invasiveness, and extracellular vesicle (EVs) are also expected to become an important pillar in the diagnostic technology system as a newly discovered active substance carrier. More and more research has highlighted the important contribution of EVs in the progress of tumor. Molecular changes during disease progression could be detected in EVs. However, the diagnostic applications of EVs are not generally understood. Combined with the characteristics of hepatobiliary and pancreatic tumor, we summarized the recent developments in various omics analysis of EVs. Furtherly, we explored the role of EVs in the early diagnosis of hepatobiliary and pancreatic tumors by multi-omics analysis.

Ablation of high-mobility group box-1 in the liver reduces hepatocellular carcinoma but causes hyperbilirubinemia in Hippo signaling-deficient mice

Silencing the Hippo kinases mammalian sterile 20-like 1 and 2 (MST1/2) activates the transcriptional coactivator yes-associated protein (YAP) in human hepatocellular carcinoma (HCC). Hepatocyte-derived high-mobility group box-1 (HMGB1) regulates YAP expression; however, its contribution to HCC in the context of deregulated Hippo signaling is unknown. Here, we hypothesized that HMGB1 is required for hepatocarcinogenesis by activating YAP in Hippo signaling-deficient (Mst1/2ΔHep ) mice. Mst1/2ΔHep mice developed HCC within 3.5 months of age and had increased hepatic expression of HMGB1 and elevated YAP activity compared to controls. To understand the contribution of HMGB1, we generated Mst1/2&Hmgb1ΔHep mice. They exhibited decreased YAP activity, cell proliferation, inflammation, fibrosis, atypical ductal cell expansion, and HCC burden at 3.5 months compared to Mst1/2∆Hep mice. However, Mst1/2&Hmgb1ΔHep mice were smaller, developed hyperbilirubinemia, had more liver injury with intrahepatic biliary defects, and had reduced hemoglobin compared to Mst1/2ΔHep mice. Conclusion: Hepatic HMGB1 promotes hepatocarcinogenesis by regulation of YAP activity; nevertheless, it maintains intrahepatic bile duct physiology under Hippo signaling deficiency.

MRI features of histologic subtypes of hepatocellular carcinoma: correlation with histologic, genetic, and molecular biologic classification

HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression. Advancements in imaging techniques have allowed imaging diagnosis to become a critical part of managing HCC in the clinical setting, even without pathologic diagnosis. With the identification of many HCC subtypes, there is increasing correlative evidence between imaging phenotypes and histologic, molecular, and genetic characteristics of various HCC subtypes. In this review, current knowledge of histologic heterogeneity of HCC correlated to features on gadolinium-enhanced dynamic liver MRI will be discussed. In addition, HCC subtype classification according to transcriptomic profiles will be outlined with descriptions of histologic, genetic, and molecular characteristics of some relatively well-established morphologic subtypes, namely the low proliferation class (steatohepatitic HCC and CTNNB1-mutated HCC) and the high proliferation class (macrotrabecular-massive HCC (MTM-HCC), scirrhous HCC, and CK19-positive HCC). Characteristics of sarcomatoid HCC and fibrolamellar HCC will also be discussed. Further research on radiological characteristics of HCC subtypes may ultimately enable non-invasive diagnosis and serve as a biomarker in predicting prognosis, molecular characteristics, and therapeutic response. In the era of precision medicine, a multidisciplinary effort to develop an integrated radiologic and clinical diagnostic system of various HCC subtypes is necessary. KEY POINTS: • HCC is a heterogeneous group of tumors in terms of histology, genetic aberration, and protein expression, which can be divided into many subtypes according to transcriptome profiles. • There is increasing evidence of a correlation between imaging phenotypes and histologic, genetic, and molecular biologic characteristics of various HCC subtypes. • Imaging characteristics may ultimately enable non-invasive diagnosis and subtype characterization, serving as a biomarker for predicting prognosis, molecular characteristics, and therapeutic response.

FOXM1 Is a Novel Molecular Target of AFP-Positive Hepatocellular Carcinoma Abrogated by Proteasome Inhibition

Alpha-fetoprotein (AFP) is an oncofetal protein that is elevated in a subset of hepatocellular carcinoma (HCC) with poor prognosis, but the molecular target activated in AFP-positive HCC remains elusive. Here, we demonstrated that the transcription factor forkhead box M1 (FOXM1) is upregulated in AFP-positive HCC. We found that FOXM1 expression was highly elevated in approximately 40% of HCC cases, and FOXM1-high HCC was associated with high serum AFP levels, a high frequency of microscopic portal vein invasion, and poor prognosis. A transcriptome and pathway analysis revealed the activation of the mitotic cell cycle and the inactivation of mature hepatocyte metabolism function in FOXM1-high HCC. The knockdown of FOXM1 reduced AFP expression and induced G2/M cell cycle arrest. We further identified that the proteasome inhibitor carfilzomib attenuated FOXM1 protein expression and suppressed cell proliferation in AFP-positive HCC cells. Carfilzomib in combination with vascular endothelial growth factor receptor 2 (VEGFR2) blockade significantly prolonged survival by suppressing AFP-positive HCC growth in a subcutaneous tumor xenotransplantation model. These data indicated that FOXM1 plays a pivotal role in the proliferation of AFP-positive liver cancer cells. Carfilzomib can effectively inhibit FOXM1 expression to inhibit tumor growth and could be a novel therapeutic option in patients with AFP-positive HCC who receive anti-VEGFR2 antibodies.

PI3Kδ activity controls plasticity and discriminates between EMT and stemness based on distinct TGFβ signaling

The stem cells involved in formation of the complex human body are epithelial cells that undergo apicobasal polarization and form a hollow lumen. Epithelial plasticity manifests as epithelial to mesenchymal transition (EMT), a process by which epithelial cells switch their polarity and epithelial features to adopt a mesenchymal phenotype. The connection between the EMT program and acquisition of stemness is now supported by a substantial number of reports, although what discriminates these two processes remains largely elusive. In this study, based on 3D organoid culture of hepatocellular carcinoma (HCC)-derived cell lines and AAV8-based protein overexpression in the mouse liver, we show that activity modulation of isoform δ of phosphoinositide 3-kinase (PI3Kδ) controls differentiation and discriminates between stemness and EMT by regulating the transforming growth factor β (TGFβ) signaling. This study provides an important tool to control epithelial cell fate and represents a step forward in understanding the development of aggressive carcinoma.

CRISPR/Cas9 Screens Reveal that Hexokinase 2 Enhances Cancer Stemness and Tumorigenicity by Activating the ACSL4-Fatty Acid β-Oxidation Pathway

Metabolic reprogramming is often observed in carcinogenesis, but little is known about the aberrant metabolic genes involved in the tumorigenicity and maintenance of stemness in cancer cells. Sixty-seven oncogenic metabolism-related genes in liver cancer by in vivo CRISPR/Cas9 screening are identified. Among them, acetyl-CoA carboxylase 1 (ACC1), aldolase fructose-bisphosphate A (ALDOA), fatty acid binding protein 5 (FABP5), and hexokinase 2 (HK2) are strongly associated with stem cell properties. HK2 further facilitates the maintenance and self-renewal of liver cancer stem cells. Moreover, HK2 enhances the accumulation of acetyl-CoA and epigenetically activates the transcription of acyl-CoA synthetase long-chain family member 4 (ACSL4), leading to an increase in fatty acid β-oxidation activity. Blocking HK2 or ACSL4 effectively inhibits liver cancer growth, and GalNac-siHK2 administration specifically targets the growth of orthotopic tumor xenografts. These results suggest a promising therapeutic strategy for the treatment of liver cancer.

Direct Conversion of Human Endothelial Cells Into Liver Cancer-Forming Cells Using Nonintegrative Episomal Vectors

Liver cancer is an aggressive cancer associated with a poor prognosis. Development of therapeutic strategies for liver cancer requires fundamental research using suitable experimental models. Recent progress in direct reprogramming technology has enabled the generation of many types of cells that are difficult to obtain and provide a cellular resource in experimental models of human diseases. In this study, we aimed to establish a simple one-step method for inducing cells that can form malignant human liver tumors directly from healthy endothelial cells using nonintegrating episomal vectors. To screen for factors capable of inducing liver cancer-forming cells (LCCs), we selected nine genes and one short hairpin RNA that suppresses tumor protein p53 (TP53) expression and introduced them into human umbilical vein endothelial cells (HUVECs), using episomal vectors. To identify the essential factors, we examined the effect of changing the amounts and withdrawing individual factors. We then analyzed the proliferation, gene and protein expression, morphologic and chromosomal abnormality, transcriptome, and tumor formation ability of the induced cells. We found that a set of six factors, forkhead box A3 (FOXA3), hepatocyte nuclear factor homeobox 1A (HNF1A), HNF1B, lin-28 homolog B (LIN28B), MYCL proto-oncogene, bHLH transcription factor (L-MYC), and Kruppel-like factor 5 (KLF5), induced direct conversion of HUVECs into LCCs. The gene expression profile of these induced LCCs (iLCCs) was similar to that of human liver cancer cells, and these cells effectively formed tumors that resembled human combined hepatocellular-cholangiocarcinoma following transplantation into immunodeficient mice. Conclusion: We succeeded in the direct induction of iLCCs from HUVECs by using nonintegrating episomal vectors. iLCCs generated from patients with cancer and healthy volunteers will be useful for further advancements in cancer research and for developing methods for the diagnosis, treatment, and prognosis of liver cancer.

Prognostic impact of C-reactive protein and alpha-fetoprotein in immunotherapy score in hepatocellular carcinoma patients treated with atezolizumab plus bevacizumab: a multicenter retrospective study

AIM

This study aimed to investigate the utility of C-reactive protein (CRP) and alpha-fetoprotein (AFP) in immunotherapy (CRAFITY) score in hepatocellular carcinoma (HCC) patients receiving atezolizumab and bevacizumab (Atez/Bev).

METHODS

This retrospective cohort study included a total of 297 patients receiving Atez/Bev from September 2020 to November 2021 at 21 different institutions and hospital groups in Japan. Patients with AFP ≥ 100 ng/mL and those with CRP ≥ 1 mg/dL were assigned a CRAFITY score of 1 point.

RESULTS

The patients were assigned CRAFITY scores of 0 points (n = 147 [49.5%]), 1 point (n = 111 [37.4%]), and 2 points (n = 39 [13.1%]). AFP ≥ 100 ng/mL and CRP ≥ 1.0 mg/dL were significantly associated with progression-free survival (PFS) and overall survival (OS). The median PFS in the CRAFITY score 0, 1, and 2 groups was 11.8 months (95% confidence interval [CI] 6.4-not applicable [NA]), 6.5 months (95% CI 4.6-8.0), and 3.2 months (95% CI 1.9-5.0), respectively (p < 0.001). The median OS in patients with CRAFITY score 0, 1 and 2 was not reached, 14.3 months (95% CI 10.5-NA), and 11.6 months (95% CI 4.9-NA), respectively. The percentage of patients with grade ≥ 3 liver injury, any grade of decreased appetite, any grade of proteinuria, any grade of fever, and any grade of fatigue was lowest in patients with a CRAFITY score of 0, followed by patients with CRAFITY scores of 1 and 2.

CONCLUSIONS

The CRAFITY score is simple and could be useful for predicting therapeutic outcomes and treatment-related adverse events.

Liver cancer heterogeneity modeled by in situ genome editing of hepatocytes

Mechanistic study and precision treatment of primary liver cancer (PLC) are hindered by marked heterogeneity, which is challenging to recapitulate in any given liver cancer mouse model. Here, we report the generation of 25 mouse models of PLC by in situ genome editing of hepatocytes recapitulating 25 single or combinations of human cancer driver genes. These mouse tumors represent major histopathological types of human PLCs and could be divided into three human-matched molecular subtypes based on transcriptomic and proteomic profiles. Phenotypical characterization identified subtype- or genotype-specific alterations in immune microenvironment, metabolic reprogramming, cell proliferation, and expression of drug targets. Furthermore, single-cell analysis and expression tracing revealed spatial and temporal dynamics in expression of pyruvate kinase M2 (Pkm2). Tumor-specific knockdown of Pkm2 by multiplexed genome editing reversed the Warburg effect and suppressed tumorigenesis in a genotype-specific manner. Our study provides mouse PLC models with defined genetic drivers and characterized phenotypical heterogeneity suitable for mechanistic investigation and preclinical testing.

In situ growth of WO3/BiVO4 nanoflowers onto cellulose fibers to construct photoelectrochemical/colorimetric lab-on-paper devices for the ultrasensitive detection of AFP

In this work, novel dual-mode lab-on-paper devices based on in situ grown WO₃/BiVO₄ heterojunctions onto cellulose fibers, as signal amplification probes, were successfully fabricated by the integration of photoelectrochemical (PEC)/colorimetric analysis technologies into a paper sensing platform for the ultrasensitive detection of alpha-fetoprotein (AFP). Specifically, to achieve an impressive PEC performance of the lab-on-paper device, the WO₃/BiVO₄ heterojunction was in situ grown onto the surface of cellulose fibers assisted with Au nanoparticle (Au NP) functionalization for enhancing the conductivity of the working zone of the device. With the target concentration increased, more immune conjugates could be captured by the proposed paper photoelectrode, which could lead to a quantitative decrease in the photocurrent intensity, eventually realizing the accurate PEC signal readout. To meet the requirement of end-user application, a colorimetric signal readout system was designed for the lab-on-paper device based on the color reaction of 3,3'5,5'-tetramethylbenzidine (TMB) oxidized by WO₃/BiVO₄ nanoflowers in the presence of H₂O₂. Noticeably, it is the first time that the WO₃/BiVO₄ heterojunction is in situ grown onto cellulose fibers, which enhances the sensitivity in view of both their PEC activity and catalytic ability. By controlling the conversion process of hydrophobicity and hydrophilicity on the lab-on-paper device combined with diverse origami methods, the dual-mode PEC/colorimetric signal output for the ultrasensitive AFP detection was realized. Under optimal conditions, the proposed dual-mode lab-on-paper device could enable the sensitive PEC/colorimetric diagnosis of AFP in the linear range of 0.09-100 ng mL^-1 and 5-100 ng mL^-1 with the limit of detection of 0.03 and 1.47 ng mL^-1, respectively.

Deciphering cancer stem cells in liver cancers: new tools with improved resolution

Hepatocellular carcinoma (HCC) is the major form of liver cancer in the world with the highest prevalence in Asia. Intra-tumoral heterogeneity is a fundamental characteristic of liver cancer that impacts on its disease progression and treatment response. The cancer stem cell (CSC) subpopulation is one of the driving forces of tumor cell heterogeneity because it can regenerate cells of different properties as to maintain the tumor bulk of origin. Tremendous effort has been made in the past two decades to identify liver CSCs and promote corresponding treatment strategies for HCC. From xenotransplantation and lineage tracing techniques to the current state-of-the-art single-cell sequencing technologies, advances in research tools fuel the exciting new discoveries in the field of CSCs. In particular, single-cell analysis has spearheaded a new era, with the ability to detect heterogeneity, cellular dynamics, and transition of CSCs and their progenies at a high resolution. This commentary attempts to briefly review the evolution of tools to evaluate CSCs in liver cancers, discuss their contributions and limitations, as well as their combined and complementary utilization with techniques like human tumor organoid culture. By recognizing the shortcomings of each technique, we can reassess the blind spots of CSC studies and with this knowledge, hopefully contribute to a better understanding of hepatocarcinogenesis.

Facile Synthesis of NaYF4:Yb Up-Conversion Nanoparticles Modified with Photosensitizer and Targeting Antibody for In Vitro Photodynamic Therapy of Hepatocellular Carcinoma

Rare Earth up-conversion nanoparticles NaYF4:20%Yb,2%Er@PEI (UCNPs) were generated via a one-step hydrothermal technique at relatively reduced temperatures. Photosensitizer Ce6 and anti-EpCAM, a highly expressed monoclonal antibody in cancer stem cells of hepatocellular carcinoma, were linked to UCNP surfaces via the formation of amide linkage between carboxyl from Ce6 or anti-EpCAM and abundant amino from PEI, leading to the formation of Ps-Ce6 and anti-EpCAM-UCNPs-Ce6 nanoparticles. The synthesized nanoparticles characterized by XRD, TEM, and IR, and their zeta potential, ROS generation ability, Ce6 loading rate, and up-conversion fluorescence properties were investigated. It has been revealed that all the products were uniformly dispersed nanoparticles (25–32 nm), which crystallized primarily as hexagonal structures, and their up-conversion fluorescence spectra were similar to that of NaYF4:20%Yb,2%Er. The Ce6 loading rate in the anti-EpCAM-UCNPs-Ce6 nanoparticles was about 2.9%, thereby resulting in good ROS generation ability. For anti-EpCAM-UCNPs-Ce6, the biosafety, targeting effect, and PDT effect exposed under near-infrared (NIR) laser (980 nm) were evaluated using human liver cancer cells (BEL-7404). The results showed that it has good biocompatibility and biosafety as well as high targeting and PDT treatment efficiencies, which renders it a potential experimental material for the near-infrared PDT study.

Comprehensive Analysis Identified Mutation-Gene Signature Impacts the Prognosis Through Immune Function in Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is a life-threatening and refractory malignancy with poor outcome. Genetic mutations are the hallmark of cancer. Thus far, there is no comprehensive prognostic model constructed by mutation-gene transcriptome in HCC. The prognostic value of mutation-gene signature in HCC remains elusive.

Methods

RNA expression profiles and the corresponding clinical information were recruited from The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. The least absolute shrinkage and selection operator (LASSO) Cox regression analysis was employed to establish gene signature. Kaplan–Meier curve and time-dependent receiver operating characteristic curve were implemented to evaluate the prognostic value. The Wilcoxon test was performed to analyze the expression of immune checkpoint genes, cell cycle genes, and tumor drug resistance genes in different risk groups. Finally, quantitative real-time PCR (qRT-RCR) and immunohistochemistry (IHC) were performed to validate the mRNA and protein expression between HCC and adjacent nontumorous tissues in an independent cohort.

Results

A prognostic model consisting of five mutated genes was established by LASSO Cox regression analysis. The prognostic model classified patients into high- and low-risk groups. Compared with the low‐risk group, patients in the high‐risk group had significantly worse survival results. The prognostic model can accurately predict the overall survival of HCC patients and predict overall survival more accurately when combined with stage. Furthermore, the immune checkpoint genes, cell cycle genes, and tumor drug resistance genes were higher expressed in the high-risk group compared in the low-risk group. In addition, the expression level of prognostic signature genes was validated in an independent sample cohort, which was consistent with RNA sequencing expression in the TCGA database.

Conclusion

The prediction model of HCC constructed using mutation-related genes is of great significance for clinical decision making and the personalized treatment of patients with HCC.

Dickkopf-1 Promotes Angiogenesis and is a Biomarker for Hepatic Stem Cell-like Hepatocellular Carcinoma

Cancer stemness evinces interest owing to the resulting malignancy and poor prognosis. We previously demonstrated that hepatic stem cell-like hepatocellular carcinoma (HpSC-HCC) is associated with high vascular invasion and poor prognosis. Dickkopf-1 (DKK-1), a Wnt signaling regulator, is highly expressed in HpSC-HCC. Here, we assessed the diagnostic and prognostic potential of serum DKK-1. Its levels were significantly higher in 391 patients with HCC compared with 205 patients with chronic liver disease. Receiver operating characteristic curve analysis revealed the optimal cutoff value of DKK-1 to diagnose HCC and predict the 3-year survival as 262.2 and 365.9 pg/mL, respectively. HCC patients with high-serum DKK-1 levels showed poor prognosis. We evaluated the effects of anti-DKK-1 antibody treatment on tumor growth in vivo and of recombinant DKK-1 on cell proliferation, invasion, and angiogenesis in vitro. DKK-1 knockdown decreased cancer cell proliferation, migration, and invasion. DKK-1 supplementation promoted angiogenesis in vitro; this effect was abolished by an anti-DKK-1 antibody. Co-injection of the anti-DKK-1 antibody with Huh7 cells inhibited their growth in NOD/SCID mice. Thus, DKK-1 promotes proliferation, migration, and invasion of HCC cells and activates angiogenesis in vascular endothelial cells. DKK-1 is a prognostic biomarker for HCC and a functional molecule for targeted therapy.

rs62139665 Polymorphism in the Promoter Region of EpCAM Is Associated With Hepatitis C Virus-Related Hepatocellular Carcinoma Risk in Egyptians

Hepatocellular carcinoma (HCC) is a universal health problem that is particularly alarming in Egypt. The major risk factor for HCC is hepatitis C virus (HCV) infection which is a main burden in Egypt. The epithelial cell adhesion molecule (EpCAM) is a stem cell marker involved in the tumorigenesis and progression of many malignancies, including HCC. We investigated the association of -935 C/G single nucleotide polymorphism in EpCAM promoter region (rs62139665) with HCC risk, EpCAM expression and overall survival in Egyptians. A total of 266 patients (128 HCV and 138 HCC cases) and 117 age- and sex-matched controls participated in this study. Genotyping, performed using allelic discrimination and confirmed by sequencing, revealed a significant association between EpCAM rs62139665 and HCC susceptibility, with higher GG genotype and G allele distribution in HCC patients than in non-HCC subjects. Such association was not detected in HCV patients compared to controls. EpCAM gene expression levels, determined in blood by RT-qPCR, and its serum protein expression levels, determined by ELISA, were significantly higher in GG relative to GC+CC genotype carriers in HCV and HCC patients in a recessive model. ROC analysis of EpCAM protein levels revealed significant discriminatory power between HCC patients and non-HCC subjects, with improved diagnostic accuracy when combining α-fetoprotein and EpCAM compared to that of α-fetoprotein alone. Altogether, EpCAM rs62139665 polymorphism is significantly associated with HCC and with EpCAM gene and protein expression levels in the Egyptian population. Moreover, serum EpCAM levels may hold promise for HCC diagnosis and for improving the diagnostic accuracy of α-fetoprotein.

The Landscape Of Alpha Fetoprotein In Hepatocellular Carcinoma: Where Are We?

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has been acknowledged as a leading cause of death among cirrhosis patients. Difficulties in early diagnosis and heterogeneity are obstacles to effective treatment, especially for advanced HCC. Liver transplantation (LT) is considered the best therapy for HCC. Although many biomarkers are being proposed, alpha-fetoprotein (AFP), which was identified over 60 years ago, remains the most utilized. Recently, much hope has been placed in the immunogenicity of AFP to develop novel therapies, such as AFP vaccines and AFP-specific adoptive T-cell transfer (ACT). This review summarizes the performance of AFP as a biomarker for HCC diagnosis and prognosis, as well as its correlation with molecular classes. In addition, the role of AFP in LT is also described. Finally, we highlight the mechanism and application prospects of two immune therapies (AFP vaccine and ACT) for HCC. In general, our review points out the prevalence of AFP in HCC, accompanied by some controversies and novel directions for future research.

Recent advances in systemic therapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and lethal malignant tumors in the world. Therapeutic options for advanced HCC are limited. Systemic treatment, especially with conventional cytotoxic drugs, is usually ineffective. For more than a decade, sorafenib has been the only systemic drug that has been proven to be clinically effective for treating advanced HCC. However, over the past three years, the rapid progress of molecular targeted therapies has dramatically changed the treatment landscape for advanced HCC. Immune checkpoint therapies are now being incorporated into HCC therapies, and their combination with molecular targeted therapy is emerging as a tool to enhance the immune response. In this review, we summarize the development and progress of molecular targeted agents and immunotherapies in HCC.

Cancer stem cells in hepatocellular carcinoma - from origin to clinical implications

Hepatocellular carcinoma (HCC) is an aggressive disease with a poor clinical outcome. The cancer stem cell (CSC) model states that tumour growth is powered by a subset of tumour stem cells within cancers. This model explains several clinical observations in HCC (as well as in other cancers), including the almost inevitable recurrence of tumours after initial successful chemotherapy and/or radiotherapy, as well as the phenomena of tumour dormancy and treatment resistance. The past two decades have seen a marked increase in research on the identification and characterization of liver CSCs, which has encouraged the design of novel diagnostic and treatment strategies for HCC. These studies revealed novel aspects of liver CSCs, including their heterogeneity and unique immunobiology, which are suggestive of opportunities for new research directions and potential therapies. In this Review, we summarize the present knowledge of liver CSC markers and the regulators of stemness in HCC. We also comprehensively describe developments in the liver CSC field with emphasis on experiments utilizing single-cell transcriptomics to understand liver CSC heterogeneity, lineage-tracing and cell-ablation studies of liver CSCs, and the influence of the CSC niche and tumour microenvironment on liver cancer stemness, including interactions between CSCs and the immune system. We also discuss the potential application of liver CSC-based therapies for treatment of HCC.

Efficacy and Safety of Second-line Treatments in Patients with Advanced Hepatocellular Carcinoma after Sorafenib Failure: A Meta-analysis

BACKGROUND AND AIMS

In the last decade, several second-line therapies followed by sorafenib in patients with advanced hepatocellular carcinoma (HCC) have been reported. But the outcomes were different from each other. This meta-analysis aimed to evaluate the efficacy and safety of the second-line therapies followed by sorafenib in patients with advanced HCC.

METHODS

Embase (1974 to October 2019) and Ovid MEDLINE (1946 to October 2019) were searched for randomized clinical trials on second-line therapies followed by sorafenib in patients with advanced HCC. The quality of each study was assessed by the modified Jadad scale. Statistical analysis was carried out by RevMan5.3 software. Efficacy and safety were analyzed. Efficacy included overall survival (OS), disease control rate, time to progression, and progression-free survival.

RESULTS

Eight studies involving 3,173 patients were eligible. No difference in OS was found between the second-line treatment group and the control group (HR=0.87, 95% CI: 0.74-1.01, p=0.06). Disease control rate (relative risk (RR)=1.36, 95% CI: 1.16-1.60, p=0.0002), time to progression (HR=0.64, 95% CI: 0.51-0.81, p=0.0002) and progression-free survival (HR=0.60, 95% CI: 0.46-0.77, p<0.0001) were significantly improved by the second-line therapies. There was a slight difference in adverse events of any grade (RR=1.07, 95% CI: 1.00-1.14, p=0.03) between the two groups.

CONCLUSIONS

These second-line therapies followed by sorafenib may potentially improve the prognosis in patients with advanced HCC. Compared with other second-line therapies, regorafenib seemed to be more effective.

Role of Biobanks for Cancer Research and Precision Medicine in Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular carcinoma (HCC) is a highly complex and deadly cancer. There is an urgent need for new and effective treatment modalities. Since the primary goal in the management of cancer is to cure and improve survival, personalized therapy can increase survival, reduce mortality rates, and improve quality of life. Biobanks hold potential in leading to breakthroughs in biomedical research and precision medicine (PM). They serve as a biorepository, collecting, processing, storing, and supplying specimens and relevant data for basic, translational, and clinical research.

OBJECTIVE

We aimed to highlight the fundamental role of biobanks, harboring high quality, sustainable collections of patient samples in adequate size and variability, for developing diagnostic, prognostic, and predictive biomarkers to develop and PM approaches in the management of HCC.

METHOD

We obtained information from previously published articles and BBMRI directory.

RESULTS AND CONCLUSION

Biobanking of high-quality biospecimens along with patient clinical information provides a fundamental scientific infrastructure for basic, translational, and clinical research. Biobanks that control and eliminate pre-analytical variability of biospecimens, provide a platform to identify reliable biomarkers for the application of PM. We believe, establishing HCC biobanks will empower to underpin molecular mechanisms of HCC and generate strategies for PM. Thus, first, we will review current therapy approaches in HCC care. Then, we will summarize challenges in HCC management. Lastly, we will focus on the best practices for establishing HCC biobanking to support research, translational medicine in the light of new experimental research conducted with the aim of delivering PM for HCC patients.

Recent updates on chimeric antigen receptor T cell therapy for hepatocellular carcinoma

Chimeric antigen receptor T cell (CAR-T) therapy is novel tumor immunotherapy that enables T cells to specifically recognize tumor-associated antigens through genetic engineering technology, thus exerting antitumor effects, and it has achieved encouraging outcomes in leukemia and lymphoma. Building on excellent progress, CAR-T therapy is also expected to work well in solid tumors. Hepatocellular carcinoma (HCC), the most common primary liver cancer, is usually diagnosed at an advanced stage. Current management options for HCC remain limited, and although previous studies have indicated the feasibility of CAR-T cells, ideal therapeutic effects have not yet been achieved. This is, in part, due to the heterogeneity of tumor antigens, high intratumor pressure, immunosuppressive microenvironment, CAR-T cell exhaustion, and serious adverse reactions, which compromise the therapeutic efficiency of CAR-T immunotherapy in HCC. To overcoming these challenges, many ongoing preclinical and clinical studies were conducted. This review summarizes current CAR-T therapy targets in the treatment of HCC, discusses current obstacles and possible solutions in the process, and describes potential strategies to improve the efficacy of CAR-T cells for patients with HCC.

Dynamic phenotypic heterogeneity and the evolution of multiple RNA subtypes in hepatocellular carcinoma: the PLANET study

Intra-tumor heterogeneity (ITH) is a key challenge in cancer treatment, but previous studies have focused mainly on the genomic alterations without exploring phenotypic (transcriptomic and immune) heterogeneity. Using one of the largest prospective surgical cohorts for hepatocellular carcinoma (HCC) with multi-region sampling, we sequenced whole genomes and paired transcriptomes from 67 HCC patients (331 samples). We found that while genomic ITH was rather constant across stages, phenotypic ITH had a very different trajectory and quickly diversified in stage II patients. Most strikingly, 30% of patients were found to contain more than one transcriptomic subtype within a single tumor. Such phenotypic ITH was found to be much more informative in predicting patient survival than genomic ITH and explains the poor efficacy of single-target systemic therapies in HCC. Taken together, we not only revealed an unprecedentedly dynamic landscape of phenotypic heterogeneity in HCC, but also highlighted the importance of studying phenotypic evolution across cancer types.

Molecular classification of hepatocellular carcinoma: prognostic importance and clinical applications

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

Pathologic, Molecular, and Prognostic Radiologic Features of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a malignancy with variable biologic aggressiveness based on the tumor grade, presence or absence of vascular invasion, and pathologic and molecular classification. Knowledge and understanding of the prognostic implications of different pathologic and molecular phenotypes of HCC are emerging, with therapeutics that promise to provide improved outcomes in what otherwise remains a lethal cancer. Imaging has a central role in diagnosis of HCC. However, to date, the imaging algorithms do not incorporate prognostic features or subclassification of HCC according to its biologic aggressiveness. Emerging data suggest that some imaging features and further radiologic, pathologic, or radiologic-molecular phenotypes may allow prediction of the prognosis of patients with HCC. An invited commentary by Bashir is available online. Online supplemental material is available for this article. ^©RSNA, 2021.

The Relevance of SOCS1 Methylation and Epigenetic Therapy in Diverse Cell Populations of Hepatocellular Carcinoma

The suppressor of cytokine signaling 1 (SOCS1) is a tumor suppressor gene found to be hypermethylated in cancers. It is involved in the oncogenic transformation of cirrhotic liver tissues. Here, we investigated the clinical relevance of SOCS1 methylation and modulation upon epigenetic therapy in diverse cellular populations of hepatocellular carcinoma (HCC). HCC clinical specimens were evaluated for SOCS1 methylation and mRNA expression. The effect of 5-Azacytidine (5-AZA), a demethylation agent, was assessed in different subtypes of HCC cells. We demonstrated that the presence of SOCS1 methylation was significantly higher in HCC compared to peri-HCC and non-tumoral tissues (52% vs. 13% vs. 14%, respectively, p < 0.001). In vitro treatment with a non-toxic concentration of 5-AZA significantly reduced DNMT1 protein expression for stromal subtype lines (83%, 73%, and 79%, for HLE, HLF, and JHH6, respectively, p < 0.01) compared to cancer stem cell (CSC) lines (17% and 10%, for HepG2 and Huh7, respectively), with the strongest reduction in non-tumoral IHH cells (93%, p < 0.001). 5-AZA modulated the SOCS1 expression in different extents among the cells. It was restored in CSC HCC HepG2 and Huh7 more efficiently than sorafenib. This study indicated the relevance of SOCS1 methylation in HCC and how cellular heterogeneity influences the response to epigenetic therapy.

Lenvatinib with or without immune checkpoint inhibitors for patients with unresectable hepatocellular carcinoma in real-world clinical practice

BACKGROUND

Lenvatinib is regarded as the first-line therapy for patients with unresectable hepatocellular carcinoma (HCC). This study assessed the efficacy and safety of lenvatinib with or without immune checkpoint inhibitors (ICIs) in patients with unresectable HCC.

METHODS

In this multicentric retrospective study, patients with unresectable HCC who treated with lenvatinib with or without ICIs would be enrolled. Overall survival, progression-free survival, objective response rate, and disease control rate were calculated to assess the antitumor response.

RESULTS

Between January 2019 and August 2020, 65 patients received lenvatinib plus ICIs while other 45 patients received lenvatinib. The baseline characteristics were comparable between the two groups. Lenvatinib plus ICIs provided significantly higher overall survival (hazard ratio = 0.47, 95% CI 0.26-0.85; p = 0.013) and progression-free survival (hazard ratio = 0.35, 95% CI 0.20-0.63; p < 0.001) than lenvatinib monotherapy. Moreover, patients with lenvatinib plus ICIs had significantly higher objective response rate (41.5% vs 20.0%, p = 0.023) and disease control rate (72.3% vs 46.7%, p = 0.009) per RECIST v1.1 than those with lenvatinib. No treatment-related deaths were observed. Grade 3 or greater adverse events occurring in 10% or more of patients in either treatment group were hypertension [13 (20.0%) of 65 patients treated with lenvatinib plus ICIs vs 8 (17.8%) of 45 patients treated with lenvatinib], and palmar-plantar erythrodysesthesia [seven (10.8%) vs two (4.4%)].

CONCLUSIONS

In this real-world study, lenvatinib combined with ICIs showed significantly promising efficacy and manageable safety than lenvatinib alone in patients with unresectable HCC.

Second-Line Treatment Options for Hepatocellular Carcinoma: Current Landscape and Future Direction

Hepatocellular carcinoma is a leading cause of mortality worldwide, and its incidence is rising. The last few years have witnessed a proliferation of available systemic therapeutic options, with the approval of multiple agents, including immune checkpoint inhibitors and drugs targeting vascular endothelial growth factor, such as cabozantinib, regorafenib, and ramucirumab. Most recently, the combination of atezolizumab plus bevacizumab has resulted in the longest overall survival yet known in hepatocellular carcinoma, therefore changing the preferred first-line treatment from the previous options of sorafenib and lenvatinib. The aim of this review is to summarize the available clinical data for the current second-line systemic treatment options and the future perspectives in the treatment landscape of hepatocellular carcinoma.

Hepatic Cancer Stem Cells: Molecular Mechanisms, Therapeutic Implications, and Circulating Biomarkers

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. HCC is associated with multiple risk factors and is characterized by a marked tumor heterogeneity that makes its molecular classification difficult to apply in the clinics. The lack of circulating biomarkers for the diagnosis, prognosis, and prediction of response to treatments further undermines the possibility of developing personalized therapies. Accumulating evidence affirms the involvement of cancer stem cells (CSCs) in tumor heterogeneity, recurrence, and drug resistance. Owing to the contribution of CSCs to treatment failure, there is an urgent need to develop novel therapeutic strategies targeting, not only the tumor bulk, but also the CSC subpopulation. Clarification of the molecular mechanisms influencing CSC properties, and the identification of their functional roles in tumor progression, may facilitate the discovery of novel CSC-based therapeutic targets to be used alone, or in combination with current anticancer agents, for the treatment of HCC. Here, we review the driving forces behind the regulation of liver CSCs and their therapeutic implications. Additionally, we provide data on their possible exploitation as prognostic and predictive biomarkers in patients with HCC.

An Overview of the Genomic Characterization of Hepatocellular Carcinoma

Tumor classifications based on alterations in the genome, epigenome, or proteome have revealed distinct tumor subgroups that are associated with clinical outcomes. Several landmark studies have demonstrated that such classifications can significantly improve patient outcomes by enabling tailoring of therapy to specific alterations in cancer cells. Since cancer cells accumulate numerous alterations in many cancer-related genes, it is a daunting task to find and confirm important cancer-promoting alterations as therapeutic targets or biomarkers that can predict clinical outcomes such as survival and response to treatments. To aid further advances, we provide here an overview of the current understanding of molecular and genomic subtypes of hepatocellular carcinoma (HCC). System-level integration of data from multiple studies and development of new technical platforms for analyzing patient samples hold great promise for the discovery of new targets for treatment and correlated biomarkers, leading to personalized medicine for treatment of HCC patients.

Serum Laminin γ2 Monomer as a Diagnostic and Predictive Biomarker for Hepatocellular Carcinoma

BACKGROUNDS AND AIMS

Structural dynamics of basement membrane components are still to be elucidated in the process of hepatocarcinogenesis. We evaluated the characteristics of HCC expressing laminin γ2 monomer (LG2m), a basement membrane component not detected in normal tissues, for HCC diagnosis. We further determined whether elevated serum LG2m is a risk factor for HCC development in patients with chronic hepatitis C (CHC).

APPROACH AND RESULTS

In HCC cell lines, LG2m was expressed in alpha-fetoprotein (AFP)-negative, CD90-positive cells characterized by highly metastatic natures. Using 14 cell lines and 258 HCC microarray data, we identified that LG2m gene signature was associated with Hoshida's S1/Boyault's G3 molecular subclasses with poor prognosis, which could not be recognized by AFP. Serum LG2m was assessed in 24 healthy donors, 133 chronic liver disease patients, and 142 HCC patients, and sensitivity and specificity of LG2m testing for HCC diagnosis were 62.9% and 70.5%, respectively (cutoff, 30 pg/mL). We evaluated the consequence of LG2m elevation in two independent HCC cohorts (n = 47 and n = 81), and LG2m-high HCC showed poor prognosis with later development of distant organ metastasis (cutoff, 60 pg/mL). LG2m was slightly elevated in a subset of CHC patients, and Kaplan-Meier analysis indicated a high incidence of HCC (n = 70). For validation, we enrolled 399 CHC patients with sustained virological response (SVR) as a multicenter, prospective study, and serum LG2m elevation correlated with a high incidence of HCC in the CHC patients with SVR (P < 0.0001).

CONCLUSIONS

LG2m is a predictive biomarker for the development of metastatic HCC. Elevated serum LG2m is an HCC risk in CHC patients who have achieved SVR.

Immunotherapy against programmed death-1/programmed death ligand 1 in hepatocellular carcinoma: Importance of molecular variations, cellular heterogeneity, and cancer stem cells

Hepatocellular carcinoma (HCC) is a heterogeneous malignancy related to diverse etiological factors. Different oncogenic mechanisms and genetic variations lead to multiple HCC molecular classifications. Recently, an immune-based strategy using immune checkpoint inhibitors (ICIs) was presented in HCC therapy, especially with ICIs against the programmed death-1 (PD-1) and its ligand PD-L1. However, despite the success of anti-PD-1/PD-L1 in other cancers, a substantial proportion of HCC patients fail to respond. In this review, we gather current information on biomarkers of anti-PD-1/PD-L1 treatment and the contribution of HCC heterogeneity and hepatic cancer stem cells (CSCs). Genetic variations of PD-1 and PD-L1 are associated with chronic liver disease and progression to cancer. PD-L1 expression in tumoral tissues is differentially expressed in CSCs, particularly in those with a close association with the tumor microenvironment. This information will be beneficial for the selection of patients and the management of the ICIs against PD-1/PD-L1.

Evolving therapeutic strategies for advanced hepatocellular carcinoma

Introduction: While sorafenib dominated the therapeutic arena in advanced hepatocellular carcinoma (HCC) for almost a decade, newer agents and combinations have been changing the therapeutic landscape in the last years.Areas covered: The authors outline the etiopathogenesis and evaluate the diagnostics in HCC, followed by a comprehensive review of the currently approved and experimental treatment approaches, with a focus on various systemic agents and combinations of agents. The manuscript was subdivided into relevant categories, thus making it applicable for both clinical practice and research endeavors.Expert opinion: Recently, combination therapies including immune checkpoint inhibitors with anti-VEGF/R agents have shown superior clinical efficacy in HCC. The Atezolizumab-bevacizumab combination is currently the preferred first-line therapy. Single-agents cabozantinib and regorafenib as well as nivolumab-ipilimumab combination are favored as second-line therapies. Further research is needed to identify the predictors of response to various treatments and establish the distinct patient profiles that will derive most benefit. Tumor mutation analysis and germline mutation testing could identify rational therapeutic targets in HCC in the near future. As the skyline for new therapeutic agents and combinations in HCC continues to expand, the outlook as of today is cautiously optimistic in this still difficult-to-treat malignant neoplastic disease.

Sorafenib and hepatocellular carcinoma: is alpha-fetoprotein a biomarker predictive of tumor biology and primary resistance?

Background: Alpha-fetoprotein (AFP) is the only biomarker with proven prognostic value in advanced hepatocellular carcinoma. Preliminary data indicate crosstalk between AFP and VEGF signaling. Methods: The authors looked at 69 patients with advanced hepatocellular carcinoma who were previously tested for VEGFR2 expression, had available baseline AFP serum concentrations and were treated with sorafenib within clinical trials. Results: Shorter progression-free survival and overall survival were associated with increased AFP level and elevated VEGFR2 staining. At multivariate analysis of AFP level was the only independent prognostic factor for progression-free survival and overall survival. Conclusion: The authors' study confirms the adverse prognostic role of elevated baseline AFP and also suggests a possible role of AFP in primary resistance to sorafenib therapy.

Tumor metabolism and associated serum metabolites define prognostic subtypes of Asian hepatocellular carcinoma

Treatment effectiveness in hepatocellular carcinoma (HCC) depends on early detection and precision-medicine-based patient stratification for targeted therapies. However, the lack of robust biomarkers, particularly a non-invasive diagnostic tool, precludes significant improvement of clinical outcomes for HCC patients. Serum metabolites are one of the best non-invasive means for determining patient prognosis, as they are stable end-products of biochemical processes in human body. In this study, we aimed to identify prognostic serum metabolites in HCC. To determine serum metabolites that were relevant and representative of the tissue status, we performed a two-step correlation analysis to first determine associations between metabolic genes and tissue metabolites, and second, between tissue metabolites and serum metabolites among 49 HCC patients, which were then validated in 408 additional Asian HCC patients with mixed etiologies. We found that certain metabolic genes, tissue metabolites and serum metabolites can independently stratify HCC patients into prognostic subgroups, which are consistent across these different data types and our previous findings. The metabolic subtypes are associated with β-oxidation process in fatty acid metabolism, where patients with worse survival outcome have dysregulated fatty acid metabolism. These serum metabolites may be used as non-invasive biomarkers to define prognostic tumor molecular subtypes for HCC.

Diagnostic and prognostic impact of cytokeratin 19 expression analysis in human tumors: a tissue microarray study of 13,172 tumors

To evaluate cytokeratin 19 (CK19) expression in normal and cancerous tissues, 15,977 samples from 122 tumor types and 608 samples of 76 normal tissue types were analyzed by immunohistochemistry (IHC). In normal tissues, CK19 expression occurred in epithelial cells of most glandular organs but was strictly limited to the basal cell layer of nonkeratinizing squamous epithelium and absent in the skin. CK19 expression in ≥90% of cases was seen in 34% of the tumor entities including the adenocarcinomas of the pancreas (99.4%), colorectum (99.8%), esophagus (98.7%), and stomach (97.7%), as well as breast cancer (90.0%-100%), high-grade serous (99.1%) or endometrioid (97.8%) ovarian cancer, and urothelial carcinoma (92.6%-100%). A low CK19 positivity rate (0.1-10%) was seen in 5 of 122 tumor entities including hepatocellular carcinoma and seminoma. A comparison of tumor versus normal tissue findings demonstrated that upregulation and downregulation of CK19 can occur in cancer and that both alterations can be linked to unfavorable phenotypes. CK19 downregulation was linked to high grade (p = 0.0017) and loss of estrogen receptor- and progesterone receptor-expression (p < 0.0001 each) in invasive breast carcinoma of no special type. CK19 upregulation was linked to nodal metastases in neuroendocrine tumors and papillary thyroid carcinomas (p < 0.05 each) and to poor grade in clear cell renal cell carcinoma (p < 0.05). CK19 upregulation was particularly common in squamous cell carcinomas. We concluded that CK19 IHC might separate primary liver cell carcinoma from liver metastases, seminoma from other testicular tumors, and helps in the detection of early neoplastic transformation in squamous epithelium.

The Endless Sources of Hepatocellular Carcinoma Heterogeneity

Hepatocellular carcinoma (HCC) represents a global health problem. The incidence keeps increasing and current therapeutic options confer limited benefits to the patients. Tumor heterogeneity plays a central role in this context, limiting the availability of predictive biomarkers and complicating the criteria used to choose the most suitable therapeutic option. HCC heterogeneity occurs at different levels: within the population (inter-patient heterogeneity) and within tumors from the same patient (intra-patient and intra-tumor heterogeneity). Experts in the field have made many efforts to classify the patients based on clinicopathological characteristics and molecular signatures; however, there is still much work ahead to be able to integrate the extra-tumor heterogeneity that emerges from the complexity of the tumor microenvironment, which plays a critical role in the pathogenesis of the disease and therapy responses. In this review, we summarize tumor intrinsic and extrinsic sources of heterogeneity of the most common etiologies of HCC and summarize the most recent discoveries regarding the evolutionary trajectory of liver cancer cells and the influence of tumor-extrinsic factors such as the microbiome and the host immune system. We further highlight the potential of novel high-throughput methodologies to contribute to a better understanding of this devastating disease and to the improvement of the clinical management of patients.

Clearance of Circulating Tumor Cells in Patients with Hepatocellular Carcinoma Undergoing Surgical Resection or Liver Transplantation

BACKGROUND

In patients with hepatocellular carcinoma (HCC), a complete clearance of circulating tumor cells (CTCs) early after liver transplantation (LT) or surgical resection (LR) could prevent tumor recurrence.

METHODS

prospective pilot study including patients with HCC who underwent LR or LT from September 2017 to May 2020. Enumeration of CTCs was performed in peripheral blood samples (7 mL) using the Isoflux^® system (Fluxion Biosciences) immediately before surgery, at post-operative day 5 and at day 30. A clinically relevant number of CTCs was defined as >30 CTCs/sample.

RESULTS

41 HCC patients were included (mean age 58.7 ± 6.3; 82.9% male). LR was performed in 10 patients (24.4%) and 31 patients (75.6%) underwent LT. The main etiology of liver disease was chronic hepatitis C (31.7%). Patients undergoing LR and LT were similar in terms of preoperative CTC count (p = 0.99), but clearance of CTCs within the first month was more pronounced in the LT group. Clusters of CTCs at baseline were associated with incomplete clearance of CTCs at day 30 (54.2% vs. 11.8%, p = 0.005), which in turn impacted negatively on survival (p = 0.038).

CONCLUSION

Incomplete clearance of CTCs after surgery could be a surrogate marker of HCC aggressiveness.

Systemic immune-inflammation index predicts prognosis of sequential therapy with sorafenib and regorafenib in hepatocellular carcinoma

Background

Regorafenib has shown promising results as a second-line therapy for patients with hepatocellular carcinoma (HCC) who progressed on sorafenib. Although there have been several data regarding the efficacy of sequential therapy with sorafenib and that of regorafenib in real-life, specific inflammation markers for predicting the prognosis have not been studied. This study aimed to investigate prognostic value of systemic inflammatory markers in patients with HCC who received sorafenib-regorafenib sequential therapy.

Methods

We retrospectively analyzed medical data of patients who received regorafenib for the treatment of HCC after sorafenib failure. Progression free survival (PFS) and overall survival (OS) were assessed using the Kaplan–Meier survival curves. Univariate and multivariate analyses were performed to analyze the factors associated with survival.

Results

A total of 58 patients who received at least one dose of regroafenib and fulfilled the eligibility criteria, good performance status (Eastern Cooperative Oncology Group [ECOG] 0–1) and preserved liver function (Child-Pugh-A), were included in the analysis. The median PFS was 3 months (95% confidence interval [CI] = 0.981–5.019) and the median OS was 8 months (95% CI = 5.761–10.239). Elevated systemic immune-inflammation index (SII ≥340) was independently associated with poor OS. In multivariate analysis, the SII (hazard ratio [HR] = 2.211, 95% CI = 1.089–4.489, P = 0.028) and alpha-fetoprotein (AFP) (HR = 2.750, 95% CI = 1.259–6.010, P = 0.011) were independent predictors of OS.

Conclusion

Elevated SII is associated with poor OS in patients with HCC who received sequential therapy with sorafenib and regorafenib. In addition, when selecting a treatment strategy, the SII can be used in combination with the AFP level as a promising prognostic tool for HCC.

The clinical, prognostic and therapeutic significance of liver cancer stem cells and their markers

Hepatocellular carcinoma (HCC) is the fourth most common cause of death among cancers. The poor prognosis of HCC might be caused by a population of cancer stem cells (CSC). CSC have similar characteristics to normal stem cells and are responsible for cancer recurrence, chemoresistance, radioresistance and metastasis. Liver cancer stem cells (LCSC) are identified via specific surface markers, such as CD44, CD90, CD133, and EpCAM (CD326). Recent studies suggested a complex interaction between mentioned LCSC markers and clinical features of HCC. A high expression of CSC is correlated with a negative prognostic factor after surgical resection of HCC and is connected with more aggressive tumor behavior. Moreover, LCSC might be responsible for increasing resistance to sorafenib, a kinase inhibitor drug. A reduction in the LCSC population may be crucial to successful advanced HCC therapy.

Detection of oncogenic mutations in paired circulating tumor DNA and circulating tumor cells in patients with hepatocellular carcinoma

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In paired analysis CTCs were detected in 27% and ctDNA in 77% of HCC patients.

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The TERT promoter mutation C228T was present in all patients with one or more ctDNA mutations, or detectable CTCs.

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CtDNA (or TERT C228T) positivity was associated with macrovascular invasion and poor survival of advanced HCC patients.

Background and aims

Circulating tumor cells (CTCs) or circulating tumor DNA (ctDNA) may be used for diagnostic or prognostic purposes in patients with hepatocellular carcinoma (HCC). We aim to determine whether CTCs or ctDNA are suitable to determine oncogenic mutations in HCC patients.

Methods

Twenty-six mostly advanced HCC patients were enrolled. 30 mL peripheral blood from each patient was obtained. CellSearch system was used for CTC detection. A sequencing panel covering 14 cancer-relevant genes was used to identify oncogenic mutations. TERT promoter C228T and C250T mutations were determined by droplet digital PCR.

Results

CTCs were detected in 27% (7/26) of subjects but at low numbers (median: 2 cells, range: 1–15 cells) and ctDNA in 77% (20/26) of patients. Mutations in ctDNA were identified in several genes: TERT promoter C228T (77%, 20/26), TP53 (23%, 6/26), CTNNB1 (12%, 3/26), PIK3CA (12%, 3/26) and NRAS (4%, 1/26). The TERT C228T mutation was present in all patients with one or more ctDNA mutations, or detectable CTCs. The TERT C228T and TP53 mutations detected in ctDNA were present at higher levels in matched primary HCC tumor tissue. The maximal variant allele frequency (VAF) of ctDNA was linearly correlated with largest tumor size and AFP level (Log10). CtDNA (or TERT C228T) positivity was associated with macrovascular invasion, and positivity of ctDNA (or TERT C228T) or CTCs (≥ 2) correlated with poor patient survival.

Conclusions

Oncogenic mutations could be detected in ctDNA from advanced HCC patients. CtDNA analysis may serve as a promising liquid biopsy to identify druggable mutations.

3D Culture of Circulating Tumor Cells for Evaluating Early Recurrence and Metastasis in Patients with Hepatocellular Carcinoma

Purpose

Circulating tumor cells (CTCs) are considered to be a key factor involved in tumor metastasis. However, the isolation and culture of CTCs in vitro remains challenging, and their clinical application for predicting prognosis and survival is still limited. The development of accurate evaluating system for CTCs will benefit for clinical assessment of HCC.

Methods

Density gradient centrifugation and magnetic separation based on CD45 antibody were used to isolate CTCs. 3D culture was used to maintain and amplify CTCs and HCC cells. Cellular immunofluorescence was used to identify CTCs and spheroids. The cutoff value of CTC spheroid was calculated using X-tile software. The relationship between clinicopathological variables and CTC spheroids in HCC patients is analyzed. In vivo models were used to evaluate tumor growth and metastasis of CTC spheroids.

Results

Patient-derived CTCs/HCC cells were isolated and expanded to form spheroids using 3D culture. CTC spheroids could be used to predict short-term recurrence of CTCs compared with conventional CTC enumeration. Different cell lines exhibited different formation rates and grew to different sizes. Identification of CTC spheroids revealed that EpCAM and β-catenin were expressed in spheroids derived from HCC cells and in the HCC/CTCs. EpCAM-positive HCC cells exhibited improved spheroid formation in 3D culture and were more tumorigenic and likely to metastasize to the lung in vivo. Abnormal activation of the Wnt/β-catenin signaling pathway was observed in EpCAM positive cells.

Conclusion

CTC spheroids could predict prognosis of HCC more precisely compared with conventional CTC enumeration. EpCAM may participate in the formation and survival of CTC spheroids which dependent on Wnt/β-catenin signaling pathway.

Role of Alpha-Fetoprotein in Hepatocellular Carcinoma Drug Resistance

Hepatocellular carcinoma (HCC) is a major type of primary liver cancer and a major cause of cancer-related deaths worldwide because of its high recurrence rate and poor prognosis. Surgical resection is currently the major treatment measure for patients in the early and middle stages of the disease. Because due to late diagnosis, most patients already miss the opportunity for surgery upon disease confirmation, conservative chemotherapy (drug treatment) remains an important method of comprehensive treatment for patients with middle- and late-stage liver cancer. However, multidrug resistance (MDR) in patients with HCC severely reduces the treatment effect and is an important obstacle to chemotherapeutic success. Alpha-fetoprotein (AFP) is an important biomarker for the diagnosis of HCC. The serum expression levels of AFP in many patients with HCC are increased, and a persistently increased AFP level is a risk factor for HCC progression. Many studies have indicated that AFP functions as an immune suppressor, and AFP can promote malignant transformation during HCC development and might be involved in the process of MDR in patients with liver cancer. This review describes drug resistance mechanisms during HCC drug treatment and reviews the relationship between the mechanism of AFP in HCC development and progression and HCC drug resistance.

Serum alpha-fetoprotein and clinical outcomes in patients with advanced hepatocellular carcinoma treated with ramucirumab

BACKGROUND

Post hoc analyses assessed the prognostic and predictive value of baseline alpha-fetoprotein (AFP), as well as clinical outcomes by AFP response or progression, during treatment in two placebo-controlled trials (REACH, REACH-2).

METHODS

Serum AFP was measured at baseline and every three cycles. The prognostic and predictive value of baseline AFP was assessed by Cox regression models and Subpopulation Treatment Effect Pattern Plot method. Associations between AFP (≥ 20% increase) and radiographic progression and efficacy were assessed.

RESULTS

Baseline AFP was confirmed as a continuous (REACH, REACH-2; p < 0.0001) and dichotomous (≥400 vs. <400 ng/ml; REACH, p < 0.01) prognostic factor, and was predictive for ramucirumab survival benefit in REACH (p = 0.0042 continuous; p < 0.0001 dichotomous). Time to AFP (hazard ratio [HR] 0.513; p < 0.0001) and radiographic (HR 0.549; p < 0.0001) progression favoured ramucirumab. Association between AFP and radiographic progression was shown for up to 6 (odds ratio [OR] 5.1; p < 0.0001) and 6-12 weeks (OR 1.8; p = 0.0065). AFP response was higher with ramucirumab vs. placebo (p < 0.0001). Survival was longer in patients with an AFP response than patients without (13.6 vs. 5.6 months, HR 0.451; 95% confidence interval, 0.354-0.574; p < 0.0001).

CONCLUSIONS

AFP is an important prognostic factor and a predictive biomarker for ramucirumab survival benefit. AFP ≥ 400 ng/ml is an appropriate selection criterion for ramucirumab.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, REACH (NCT01140347) and REACH-2 (NCT02435433).

MiR-125b Loss Activated HIF1α/pAKT Loop, Leading to Transarterial Chemoembolization Resistance in Hepatocellular Carcinoma

BACKGROUND AND AIMS

Transarterial chemoembolization (TACE) is a standard locoregional therapy for patients with hepatocellular carcinoma (HCC) patients with a variable overall response in efficacy. We aimed to identify key molecular signatures and related pathways leading to HCC resistance to TACE, with the hope of developing effective approaches in preselecting patients with survival benefit from TACE.

APPROACH AND RESULTS

Four independent HCC cohorts with 680 patients were used. MicroRNA (miRNA) transcriptome analysis in patients with HCC revealed a 41-miRNA signature related to HCC recurrence after adjuvant TACE, and miR-125b was the top reduced miRNA in patients with HCC recurrence. Consistently, patients with HCC with low miR-125b expression in tumor had significantly shorter time to recurrence following adjuvant TACE in two independent cohorts. Loss of miR-125b in HCC noticeably activated the hypoxia inducible factor 1 alpha subunit (HIF1α)/pAKT loop in vitro and in vivo. miR-125b directly attenuated HIF1α translation through binding to HIF1A internal ribosome entry site region and targeting YB-1, and blocked an autocrine HIF1α/platelet-derived growth factor β (PDGFβ)/pAKT/HIF1α loop of HIF1α translation by targeting the PDGFβ receptor. The miR-125b-loss/HIF1α axis induced the expression of CD24 and erythropoietin (EPO) and enriched a TACE-resistant CD24-positive cancer stem cell population. Consistently, patients with high CD24 or EPO in HCC had poor prognosis following adjuvant TACE therapy. Additionally, in patients with HCC having TACE as their first-line therapy, high EPO in blood before TACE was also noticeably related to poor response to TACE.

CONCLUSIONS

MiR-125b loss activated the HIF1α/pAKT loop, contributing to HCC resistance to TACE and the key nodes in this axis hold the potential in assisting patients with HCC to choose TACE therapy.

Liver cancer stem cells: Recent progress in basic and clinical research

The cancer stem cell (CSC) hypothesis was proposed over 4 decades ago and states that tumor growth is maintained by a small subset of cancer cells analogous to normal tissue stem cells in terms of self-renewal and differentiation capacity. Advances in CSC isolation were initially achieved in hematological malignancies and later in solid tumors, including hepatocellular carcinoma (HCC), the major histological type of liver cancer. Increasing evidence suggests the importance of liver CSCs for tumor growth, metastasis, and chemo/radiation resistance in HCC, but the application of the liver CSC concept for the clinical diagnosis and treatment of HCC has not yet been achieved to the extent initially expected. Furthermore, the heterogeneity and plasticity of liver CSCs has recently been noted and might be related to drug resistance and the rapid growth and/or metastasis of the tumor after treatment. Here, we introduce our recent advancement in liver CSC research and discuss the clinical implications, which may lead to the development of improved diagnostics and treatment in HCC.

Roles Played by YY1 in Embryonic, Adult and Cancer Stem Cells

Accumulating evidence strongly indicates that the presence of cancer stem cells (CSCs) leads to the emergence of worse clinical scenarios, such as chemo- and radiotherapy resistance, metastasis, and cancer recurrence. CSCs are a highly tumorigenic population characterized by self-renewal capacity and differentiation potential. Thus, CSCs establish a hierarchical intratumor organization that enables tumor adaptation to evade the immune response and resist anticancer therapy. YY1 functions as a transcription factor, RNA-binding protein, and 3D chromatin regulator. Thus, YY1 has multiple effects and regulates several molecular processes. Emerging evidence indicates that the development of lethal YY1-mediated cancer phenotypes is associated with the presence of or enrichment in cancer stem-like cells. Therefore, it is necessary to investigate whether and to what extent YY1 regulates the CSC phenotype. Since CSCs mirror the phenotypic behavior of stem cells, we initially describe the roles played by YY1 in embryonic and adult stem cells. Next, we scrutinize evidence supporting the contributions of YY1 in CSCs from a number of various cancer types. Finally, we identify new areas for further investigation into the YY1-CSCs axis, including the participation of YY1 in the CSC niche.