New insights into the pathophysiology and clinical care of rare primary liver cancers

Therapeutic potential of SOX9 dysruption in Combined Hepatocellular Carcinoma-Cholangiocarcinoma

Combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA) represents a challenging subtype of primary liver cancer with limited treatment options and a poor prognosis. Recently, we and others have highlighted the context-dependent roles of the biliary-specific transcription factor SOX9 in the pathogenesis of liver cancers using various Cre applications in Sox9 (flox/flox) strains, to achieve elimination for exon 2 and 3 of the Sox9 gene locus as a preventive manner. Here, we reveal the contrasting responses of developmental Sox9 elimination using Alb-Cre;Sox9 (flox/flox) ( Sox9 LKO) versus CRISPR/Cas9 -based tumor specific acute Sox9 CKO in SB-HDTVI-based Akt-YAP1 and Akt-NRAS cHCC-CCA formation. Sox9 LKO specifically abrogates the Akt-YAP1 CCA region while robustly stimulating the proliferation of remaining poorly differentiated HCC pertaining liver progenitor cell characteristics, whereas Sox9 CKO potently prevents Akt-YAP1 and Akt-NRAS cHCC-CCA development irrespective of fate of tumor cells compared to respective controls. Additionally, we find that Akt-NRAS , but not Akt-YAP1 , tumor formation is partially dependent on the Sox9-Dnmt1 cascade. Pathologically, SOX9 is indispensable for Akt-YAP1 -mediated HC-to-BEC/CCA reprogramming but required for the maintenance of CCA nodules. Lastly, therapeutic elimination of Sox9 using the OPN-CreERT2 strain combined with an inducible CRISPR/Cas9 -based Sox9 iKO significantly reduces Akt-YAP1 cHCC-CCA tumor burden, similar to Sox9 CKO. Thus, we contrast the outcomes of acute Sox9 deletion with developmental Sox9 knockout models, emphasizing the importance of considering adaptation mechanisms in therapeutic strategies. This necessitates the careful consideration of genetic liver cancer studies using developmental Cre and somatic mutant lines, particularly for genes involved in hepatic commitment during development. Our findings suggest that SOX9 elimination may hold promise as a therapeutic approach for cHCC-CCA and underscore the need for further investigation to translate these preclinical insights into clinical applications.

Proposed diagnostic and prognostic markers of primary malignant hepatic vascular neoplasms

INTRODUCTION

Primary malignant hepatic vascular tumors with various malignant potentials include epithelioid hemangioendothelioma (EHE) and angiosarcoma (AS), which may overlap pathologically. This study aimed to compare the pathological findings of hepatic EHE with those of AS, in association with patient outcomes.

METHODS

Fifty-nine histologically confirmed patients with 34 EHE and 25 AS were admitted to a tertiary hospital from 2003 to 2020. Their EHE and AS pathological features were compared. Immunohistochemistry for CD31, ERG, CAMTA-1, TFE3, P53, and Ki-67 labeling was performed on paraffin-embedded blocks. Markers, along with histological findings, were analyzed for the purposes of diagnostic and prognostic significance by multivariate analysis.

RESULTS

CAMTA-1 was 91.2% positive in EHE, but negative in AS (p = < 0.001). AS was significantly correlated to an aberrant p53 expression, high Ki-67 labeling, and high mitotic activity, compared to EHE (all, p = < 0.001). EHE can be classified as low grade (LG) and high grade (HG) using the prognostic values of mitotic activity and ki-67 labeling (sensitivity = 1, specificity = 1). Low grade-EHE showed significantly better overall survival than high grade-EHE (p = 0.020).

CONCLUSIONS

Immunohistochemistry for CAMTA-1, P53, and Ki-67 labeling may help distinguish EHE and AS in histologically ambiguous cases, especially small biopsied tissue. Moreover, the combination of mitotic activity and Ki-67 labeling can be a prognostic factor for EHE with various clinical features.

Atezolizumab and bevacizumab for non-resectable or metastatic combined hepatocellular-cholangiocarcinoma: A multicentric retrospective study

BACKGROUNDS

The efficacy of atezolizumab/bevacizumab has never been reported in patients with metastatic/unresectable combined hepatocellular-cholangiocarcinoma (cHCC-CCA).

PATIENTS AND METHODS

We retrospectively included patients with a histological diagnosis of unresectable/metastatic cHCC-CCA and treated with atezolizumab/bevacizumab (2020-2022) in 7 centers. Clinical and radiological features were collected at the beginning of atezolizumab/bevacizumab. We reported the radiological response using RECIST criteria, overall survival (OS) and progression-free survival (PFS).

RESULTS

Sixteen patients with cHCC-CCA were included and were predominantly male (75%) with advanced fibrosis/cirrhosis (69%). Nine patients received atezolizumab/bevacizumab as a first-line systemic treatment, 5 as a second line, 1 as a third line and 1 as a fifth line. Severe digestive bleeding occurred in 2 patients. Among the 9 patients treated in the first line, 4 experienced radiological progression, 3 partial response and 1 had stable disease. Patients treated with atezolizumab/bevacizumab in the first line had a median OS of 13 months and a median PFS of 3 months. Among the 7 patients receiving atezolizumab/bevacizumab as a second line or more, 4 patients harbored a stable disease, 2 a partial response, and 1 a progressive disease.

CONCLUSIONS

The combination of atezolizumab and bevacizumab showed signs of anti-tumor efficacy in patients with unresectable/metastatic cHCC-CCA.

Platycodin D2 enhances P21/CyclinA2-mediated senescence of HCC cells by regulating NIX-induced mitophagy

BACKGROUND

Hepatocellular carcinoma (HCC) cells usually show strong resistance to chemotherapy, which not only reduces the efficacy of chemotherapy but also increases the side effects. Regulation of autophagy plays an important role in tumor treatment. Cell senescence is also an important anti-cancer mechanism, which has become an important target for tumor treatment. Therefore, it is of great clinical significance to find anti-HCC drugs that act through this new mechanism. Platycodin D2 (PD2) is a new saponin compound extracted from the traditional Chinese medicine Platycodon grandiflorum.

PURPOSE

Our study aimed to explore the effects of PD2 on HCC and identify the underlying mechanisms.

METHODS

First, the CCK8 assay was used to detect the inhibitory effect of PD2 on HCC cells. Then, different pathways of programmed cell death and cell cycle regulators were measured. In addition, we assessed the effects of PD2 on the autophagy and senescence of HCC cells by flow cytometry, immunofluorescence staining, and Western blotting. Finally, we studied the in vivo effect of PD2 on HCC cells by using a mouse tumor-bearing model.

RESULTS

Studies have shown that PD2 has a good anti-tumor effect, but the specific molecular mechanism has not been clarified. In this study, we found that PD2 has no obvious toxic effect on normal hepatocytes, but it can significantly inhibit the proliferation of HCC cells, induce mitochondrial dysfunction, enhance autophagy and cell senescence, upregulate NIX and P21, and downregulate CyclinA2. Gene silencing and overexpression indicated that PD2 induced mitophagy in HCC cells through NIX, thereby activating the P21/CyclinA2 pathway and promoting cell senescence.

CONCLUSIONS

These results indicate that PD2 induces HCC cell death through autophagy and aging. Our findings provide a new strategy for treating HCC.

Transplant oncology - Current indications and strategies to advance the field

Liver transplantation (LT) was originally described by Starzl as a promising strategy to treat primary malignancies of the liver. Confronted with high recurrence rates, indications drifted towards non-oncologic liver diseases with LT finally evolving from a high-risk surgery to an almost routine surgical procedure. Continuously improving outcomes following LT and evolving oncological treatment strategies have driven renewed interest in transplant oncology. This is not only reflected by constant refinements to the criteria for LT in patients with HCC, but especially by efforts to expand indications to other primary and secondary liver malignancies. With new patient-centred oncological treatments on the rise and new technologies to expand the donor pool, the field has the chance to come full circle. In this review, we focus on the concept of transplant oncology, current indications, as well as technical and ethical aspects in the context of donor organs as precious resources.

MALDI Imaging, a Powerful Multiplex Approach to Decipher Intratumoral Heterogeneity: Combined Hepato-Cholangiocarcinomas as Proof of Concept

Combined hepato-cholangiocarcinomas (cHCC-CCA) belong to the spectrum of primary liver carcinomas, which include hepatocellular carcinomas (HCC) and intrahepatic cholangiocarcinomas (iCCA) at both ends of the spectrum. Mainly due to the high intratumor heterogeneity of cHCC-CCA, its diagnosis and pathological description remain challenging. Taking advantage of in situ non-targeted molecular mapping provided by MALDI (Matrix Assisted Laser Desorption Ionization) imaging, we sought to develop a multiscale and multiparametric morphological approach, integrating molecular and conventional pathological analysis. MALDI imaging was applied to five representative cases of resected cHCC-CCA. Principal component analysis and segmentations with MALDI imaging techniques identified areas related to either iCCA or HCC and also hidden tumor areas not visible microscopically. In addition, the overlap between MALDI segmentation and immunostaining provided a comprehensive description of cHCC-CCA tumor heterogeneity by identifying transitional and micro-metastatic areas. Moreover, a list of peptides derived from in silico digestion was obtained for each immunohistochemical marker and was matched within the peptide peak list acquired by MALDI. Comparison of immunostaining images with ions from in silico digestion revealed an accurate identification of iCCA and HCC areas. Our study provides further evidence on the performance of MALDI imaging in exploring intratumor heterogeneity and offering virtual multiplex immunostaining through a single acquisition.

Liver Organoids as an In Vitro Model to Study Primary Liver Cancer

Primary liver cancers (PLC), including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), are among the leading causes of cancer-related mortality worldwide. Bi-dimensional in vitro models are unable to recapitulate the key features of PLC; consequently, recent advancements in three-dimensional in vitro systems, such as organoids, opened up new avenues for the development of innovative models for studying tumour's pathological mechanisms. Liver organoids show self-assembly and self-renewal capabilities, retaining essential aspects of their respective in vivo tissue and allowing modelling diseases and personalized treatment development. In this review, we will discuss the current advances in the field of liver organoids focusing on existing development protocols and possible applications in regenerative medicine and drug discovery.

Combined hepatocellular carcinoma-cholangiocarcinoma with a predominant HCC component: better survival and MRI-based prediction

OBJECTIVES

To determine the optimal cutoff value of HCC% for predicting the outcome of patients with combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA) and to investigate how preoperative MR features based on the Liver Imaging Reporting and Data System (LI-RADS ver. 2018) are related to the HCC% in cHCC-CCA.

METHODS

The study enrolled 107 patients pathologically confirmed to have single cHCC-CCA according to the 2019 WHO classification. A receiver operating characteristic (ROC) curve was used to find the optimal cutoff value of HCC% based on overall survival (OS). The preoperative MR imaging features and clinicopathological findings were retrospectively evaluated and compared between the high HCC% and low HCC% groups.

RESULTS

In total, 107 patients (mean age, males vs. females: 56.6 ± 10.7 years vs. 54.2 ± 12.8 years) were evaluated. Analysis of the relationship between HCC% and OS by ROC curve suggested that the optimal cutoff value was 65%, by which 51 (47.7%) patients were assigned to the high HCC% group. LI-RADS categorization (OR = 3.657, p = 0.006 vs. OR = 4.075, p = 0.004) and serum carcinoembryonic antigen (CEA) >5 ng/mL (OR = 0.348, p = 0.089 vs. OR = 0.298, p = 0.040) were significant predictors for HCC% in cHCC-CCA in both univariate and multivariate analysis.

CONCLUSIONS

cHCC-CCA patients with HCC components higher than 65% tend to exhibit better overall survival, and MRI-based LI-RADS categorization and serum CEA level are valuable for identifying HCC% in cHCC-CCA preoperatively.

KEY POINTS

• cHCC-CCA patients with HCC components higher than 65% tend to exhibit better overall survival. • MRI-based LI-RADS categorization and serum CEA level were significant predictors for HCC% in cHCC-CCA in both univariate and multivariate analyses and valuable for identifying HCC% in cHCC-CCA preoperatively.

Holistic management of hepatocellular carcinoma: The hepatologist's comprehensive playbook

Hepatocellular carcinoma (HCC) is a common complication in patients with chronic liver disease and leads to significant morbidity and mortality. Liver disease and liver cancer are preventable by mitigating and managing common risk factors, including chronic hepatitis B and C infection, alcohol use, diabetes, obesity and other components of the metabolic syndrome. The management of patients with HCC requires treatment of the malignancy and adequate control of the underlying liver disease, as preserving liver function is critical for successful cancer treatment and may have a relevant prognostic role independent of HCC management. Hepatologists are the ideal providers to guide the care of patients with HCC as they are trained to identify patients at risk, apply appropriate surveillance strategies, assess and improve residual liver function, evaluate candidacy for transplant, provide longitudinal care to optimize and preserve liver function during and after HCC treatment, survey for cancer recurrence and manage its risk factors, and prevent and treat decompensating events. We highlight the need for a team-based holistic approach to the patient with liver disease and HCC and identify necessary gaps in current care and knowledge.

Updated information regarding management of hepatic epithelioid hemangioendothelioma

Hepatic epithelioid hemangioendothelioma (HEHE) is a rare hepatic vascular tumor with a borderline biological behavior between hemangioma and hemangiosarcoma. It tends to be multiple or diffuse subcapsular lesions across the liver but has no characteristic clinical manifestations or imaging findings. On computed tomography and magnetic resonance imaging, these lesions usually have a hypodense appearance with heterogeneous enhancement and a "halo sign" or "lollipop sign" may be evident in some cases. HEHE is diagnosed mainly based on a pathological examination along with differential immunohistochemical markers such as CAMTA1, CD31, CD34, CD10, vimentin, and factor VIII antigen. Currently, there are no standardized treatment guidelines for HEHE, and surgery (curative resection and liver transplantation) remains the mainstay of treatment. Studies have indicated that extra-hepatic metastasis might not be a contraindication for resection or transplantation. Systemic chemotherapeutic agents including doxorubicin, vincristine, interferon-a, 5-fluorouracil, and thalidomide, as well as VEGF-related agents are being investigated, but no agents have been approved for the treatment of HEHE.

Identification and Validation of Novel Biomarkers and Potential Targeted Drugs in Cholangiocarcinoma: Bioinformatics, Virtual Screening, and Biological Evaluation

Cholangiocarcinoma (CCA) is a complex and refractor type of cancer with global prevalence. Several barriers remain in CCA diagnosis, treatment, and prognosis. Therefore, exploring more biomarkers and therapeutic drugs for CCA management is necessary. CCA gene expression data was downloaded from the TCGA and GEO databases. KEGG enrichment, GO analysis, and protein-protein interaction network were used for hub gene identification. miRNA were predicted using Targetscan and validated according to several GEO databases. The relative RNA and miRNA expression levels and prognostic information were obtained from the GEPIA. The candidate drug was screened using pharmacophore-based virtual screening and validated by molecular modeling and through several in vitro studies. 301 differentially expressed genes (DEGs) were screened out. Complement and coagulation cascades-related genes (including AHSG, F2, TTR, and KNG1), and cell cycle-related genes (including CDK1, CCNB1, and KIAA0101) were considered as the hub genes in CCA progression. AHSG, F2, TTR, and KNG1 were found to be significantly decreased and the eight predicted miRNA targeting AHSG, F2, and TTR were increased in CCA patients. CDK1, CCNB1, and KIAA0101 were found to be significantly abundant in CCA patients. In addition, Molport-003-703-800, which is a compound that is derived from pharmacophores-based virtual screening, could directly bind to CDK1 and exhibited anti-tumor activity in cholangiocarcinoma cells. AHSG, F2, TTR, and KNG1 could be novel biomarkers for CCA. Molport-003-703-800 targets CDK1 and work as potential cell cycle inhibitors, thereby having potential for consideration for new chemotherapeutics for CCA.

Systemic Treatments with Tyrosine Kinase Inhibitor and Platinum-Based Chemotherapy in Patients with Unresectable or Metastatic Hepatocholangiocarcinoma

BACKGROUNDS AND AIMS

Even if no systemic treatment is currently validated for unresectable hepatocellular-cholangiocarcinoma (cHCC-CCA), tyrosine kinase inhibitors (TKIs) and platinum-based chemotherapy are frequently used in clinical practice. Our study aims to describe the effectiveness of first-line systemic treatments in patients with cHCC-CCA.

PATIENTS AND METHODS

Patients with histological diagnosis of unresectable or metastatic cHCC-CCA confirmed by a centralized review (WHO classification 2019) and who received systemic treatment from 2009 to 2020 were included retrospectively in 11 centers. The outcomes of patients with cHCC-CCA were compared with patients with hepatocellular carcinoma (HCC) treated by sorafenib (n = 117) and with intrahepatic cholangiocarcinoma (iCCA, n = 94) treated mainly by platinum-based chemotherapy using a frailty Cox model. The efficacy of TKIs and platinum-based chemotherapies in patients with cHCC-CCA was assessed using a doubly robust estimator.

RESULTS

A total of 83 patients with cHCC-CCA were included and were predominantly male (72%) with underlying cirrhosis (55%). 67% of patients had extrahepatic metastases and 31% macrovascular tumor invasion. cHCC-CCAs were more often developed on cirrhosis (55.4%) than iCCA (26.6%) but less frequently than HCC (80.2%) (p < 0.001). Both HCC (36.8% and cHCC-CCA (66.2%) had less frequent extrahepatic metastases than iCCA (81%) (p < 0.001). Unadjusted overall survival (OS) was better in iCCA (13 months) compared to cHCC-CCA (12 months) and HCC (11 months) (p = 0.130). In multivariable analysis, after adjustment by a Cox frailty model, patients with cHCC-CCA had the same survival as HCC and iCCA (HR = 0.67, 95% CI: 0.37-1.22, p = 0.189 and HR = 0.66, 95% CI: 0.43-1.02, p = 0.064, respectively). ALBI score (HR = 2.15; 95% CI: 1.23-3.76; p = 0.009), ascites (HR = 3.45, 95% CI: 1.31-9.03, p = 0.013), and tobacco use (HR = 2.29, 95% CI: 1.08-4.87, p = 0.032) were independently associated with OS in patients with cHCC-CCA. Among patients with cHCC-CCA, 25 patients treated with TKI were compared with 54 patients who received platinum-based chemotherapies. Patients treated with TKI had a median OS of 8.3 months compared to 11.9 months for patients treated with platinum-based chemotherapy (p = 0.86). After a robust doubly adjustment on tumor number and size, vascular invasion, ALBI, MELD, and cirrhosis, the type of treatment did not impact OS (HR = 0.92, 95% CI: 0.27-3.15, p = 0.88) or progression-free survival (HR = 1.24, 95% CI: 0.44-3.49, p = 0.67).

CONCLUSIONS

First-line systemic treatments with TKIs or platinum-based chemotherapies have similar efficacy in patients with unresectable/metastatic cHCC-CCA. The ALBI score predicts OS.

diTFPP, a Phenoxyphenol, Sensitizes Hepatocellular Carcinoma Cells to C2-Ceramide-Induced Autophagic Stress by Increasing Oxidative Stress and ER Stress Accompanied by LAMP2 Hypoglycosylation

Simple Summary

Chemotherapy is the major treatment modality for advanced or unresectable hepatocellular carcinoma (HCC). Unfortunately, chemoresistance carries a poor prognosis in HCC patients. Exogenous ceramide, a sphingolipid, has been well documented to exert anticancer effects; however, recent reports showed ceramide resistance, which limits the development of the ceramide-based cancer treatment diTFPP, a novel phenoxyphenol compound that has been shown to sensitize HCC cells to ceramide treatment. Here, we further clarified the mechanism underlying diTFPP-mediated sensitization of HCC to C₂-ceramide-induced stresses, including oxidative stress, ER stress, and autophagic stress, especially the modulation of LAMP2 glycosylation, the lysosomal membrane protein that is crucial for autophagic fusion. This study may shed light on the mechanism of ceramide resistance and help in the development of adjuvants for ceramide-based cancer therapeutics.

Abstract

Hepatocellular carcinoma (HCC), the most common type of liver cancer, is the leading cause of cancer-related mortality worldwide. Chemotherapy is the major treatment modality for advanced or unresectable HCC; unfortunately, chemoresistance results in a poor prognosis for HCC patients. Exogenous ceramide, a sphingolipid, has been well documented to exert anticancer effects. However, recent reports suggest that sphingolipid metabolism in ceramide-resistant cancer cells favors the conversion of exogenous ceramides to prosurvival sphingolipids, conferring ceramide resistance to cancer cells. However, the mechanism underlying ceramide resistance remains unclear. We previously demonstrated that diTFPP, a novel phenoxyphenol compound, enhances the anti-HCC effect of C₂-ceramide. Here, we further clarified that treatment with C₂-ceramide alone increases the protein level of CERS2, which modulates sphingolipid metabolism to favor the conversion of C₂-ceramide to prosurvival sphingolipids in HCC cells, thus activating the unfolded protein response (UPR), which further initiates autophagy and the reversible senescence-like phenotype (SLP), ultimately contributing to C₂-ceramide resistance in these cells. However, cotreatment with diTFPP and ceramide downregulated the protein level of CERS2 and increased oxidative and endoplasmic reticulum (ER) stress. Furthermore, insufficient LAMP2 glycosylation induced by diTFPP/ceramide cotreatment may cause the failure of autophagosome–lysosome fusion, eventually lowering the threshold for triggering cell death in response to C₂-ceramide. Our study may shed light on the mechanism of ceramide resistance and help in the development of adjuvants for ceramide-based cancer therapeutics.

Molecular Mechanisms Linking Risk Factors to Cholangiocarcinoma Development

The poor prognosis of cholangiocarcinoma in humans is related to several factors, such as (i) the heterogeneity of the disease, (ii) the late onset of symptoms and (iii) the limited comprehension of the carcinogenic pathways determining neoplastic changes, which all limit the pursuit of appropriate treatment. Several risk factors have been recognized, including different infective, immune-mediated, and dysmorphogenic disorders of the biliary tree. In this review, we report the details of possible mechanisms that lead a specific premalignant pathological condition to become cholangiocarcinoma. For instance, during liver fluke infection, factors secreted from the worms may play a major role in pathogenesis. In primary sclerosing cholangitis, deregulation of histamine and bile-acid signaling may determine important changes in cellular pathways. The study of these molecular events may also shed some light on the pathogenesis of sporadic (unrelated to risk factors) forms of cholangiocarcinoma, which represent the majority (nearly 75%) of cases.

Establishment and validation of prognostic nomograms to predict the overall and cancer-specific survival in patients with hepatic malignant vascular tumors

OBJECTIVE

To characterize the clinicopathologic features and to investigate the prognostic nomograms for overall survival (OS) and cancer-specific survival (CSS) in patients with Hepatic malignant vascular tumors (HMVT).

METHOD

Patients diagnosed with HMVT between 1973 and 2015 were screened from the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan-Meier (KM) was used for survival analysis. The univariate and multivariate Cox analyses were performed to identify independent predictors. Furthermore, the prognostic nomograms were established and evaluated.

RESULTS

A total of 510 HMVT patients were collected, and randomly divided into HMVT-training (N=308) and validation cohort (N=202) groups. The 3- and 5-year OS for overall HMVT were 21.3% and 19.8%, and the corresponding CSS was 29.8% and 27.7% respectively. Age at diagnosis, grade, tumor size, and histological type were identified as prognostic factors for OS and CSS in patients with HMVT. However, sex was just for predicting CSS, and T stage was only an indicator of OS. These factors were further utilized to construct the nomograms for OS and CSS in the HMVT-training cohort showing credible performance with the C-index of 0.763 and 0.762, respectively. Moreover, the AUC value for 1-, 3-, 5-year OS was 0.873, 0.905 and 0.898, and the corresponding value for CSS was 0.808, 0.794 and 0.788 respectively. Additionally, the calibration curves demonstrated a favorable agreement between the predicted and actual 1-, 3- and 5-year survival rates both in the training and validated cohorts.

CONCLUSION

This was the largest population-based study to describe the clinicopathologic characteristics in patients with HMVT. Moreover, we established and validated prognostic nomograms that indicated an accurate prediction for 1-, 3- and 5-year of OS and CSS.

Pediatric vascular tumors of the liver: Review from the pathologist’s point of view

Differential diagnosis of pediatric vascular liver tumors can be challenging due to inconsistent nomenclature, histologic overlap and the rarity of some entities. Here we give an up-to-date overview of the most important entities. We discuss the clinic, histology and pathophysiology of hepatic congenital and infantile heman gioma, hepatic epithelioid hemangioendothelioma and hepatic angiosarcoma.

Resistomycin Induced Apoptosis and Cycle Arrest in Human Hepatocellular Carcinoma Cells by Activating p38 MAPK Pathway In Vitro and In Vivo

Resistomycin, a quinone-related natural antibiotic, has shown strong inhibitory activity against human hepatocellular carcinoma (HCC) in vitro. Here, we investigated the role of p38 MAPK in the pro-apoptotic and G2/M phase arrest action of HCC HepG2 cells upon treatment with resistomycin in vitro and in vivo. Our results showed that resistomycin dose- and time-dependently reduced the viability of HepG2 cells and also showed lower cytotoxicity in normal human kidney cells (293T) and hepatocyte cells (HL-7702). Resistomycin treatment induced apoptosis and cell cycle arrest in HepG2 cells, accompanied by changes in the expression of related proteins, including Bax, Cyclin B1, etc. Surprisingly, resistomycin-mediated apoptotic cell death and cell cycle arrest were impeded by SB203580 (an inhibitor of p38 catalytic activity), suggesting that p38 MAPK signaling may play an important role that impedes eventual cell death. In this connection, data in vitro and in vivo demonstrated that resistomycin increased the phosphorylation of p38 and MAPKAPK-2 in HepG2 cells. Furthermore, we provided evidence that p38 signaling is involved in resistomycin-induced p38 MAPK pathway effects in HCC, using computer docking models. Our study indicated that resistomycin activates the p38 MAPK signaling pathway by which the growth of HepG2 cells is suppressed for apoptosis and G2/M phase arrest in vitro and in vivo, and it is a promising therapeutic leading compound for drug development in HCC treatment.

Rare variants of primary liver cancer: Fibrolamellar, combined, and sarcomatoid hepatocellular carcinomas

Hepatocellular carcinoma (HCC) constitutes 80% of all primary liver cancers. Based on key developments in the understanding of its carcinogenesis and the advancement of treatment options, detailed algorithms and practice guidelines have been published to guide the clinical management of HCC. Furthermore, several subclasses of HCC have been described based on molecular profiles and linked to pathological characteristics, clinical features, and disease aggressiveness. Most recently, the combination of the checkpoint inhibitor atezolizumab plus bevacizumab has significantly increased treatment response in the first line systemic treatment of HCC. Unfortunately, rare HCC variants, in particular fibrolamellar liver cancer (FLC), combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CCA), and sarcomatoid hepatocellular carcinoma (sHCC), were excluded from phase III studies. Therefore, data for decision-making and treatment allocation for these distinct entities, representing 1-5% of all primary liver cancers, is scarce. Moreover, most of the knowledge available for these rare HCC variants is based on registry data and retrospective studies. In this position paper, we briefly summarize the current clinical knowledge regarding FLC, cHCC-CCA, and sHCC. Based on our summary, we propose future clinical research activities within the framework of the European Reference Network on Hepatological Diseases (ERN RARE-LIVER).

Update on the association of hepatitis B with intrahepatic cholangiocarcinoma: Is there new evidence?

Intrahepatic cholangiocarcinoma (iCCA) is a subgroup of cholangiocarcinoma that accounts for about 10%-20% of the total cases. Infection with hepatitis B virus (HBV) is one of the most important predisposing factors leading to the formation of iCCA. It has been recently estimated based on abundant epidemiological data that the association between HBV infection and iCCA is strong with an odds ratio of about 4.5. The HBV-associated mechanisms that lead to iCCA are under intense investigation. The diagnosis of iCCA in the context of chronic liver disease is challenging and often requires histological confirmation to distinguish from hepatocellular carcinoma. It is currently unclear whether antiviral treatment for HBV can decrease the incidence of iCCA. In terms of management, surgical resection remains the mainstay of treatment. There is a need for effective treatment modalities beyond resection in both first- and second-line treatment. In this review, we summarize the epidemiological evidence that links the two entities, discuss the pathogenesis of HBV-associated iCCA, and present the available data on the diagnosis and management of this cancer.

Clinicopathologic and MRI features of combined hepatocellular-cholangiocarcinoma in patients with or without cirrhosis

BACKGROUND AND AIMS

Differences in combined hepatocellular-cholangiocarcinomas (cHCC-CCAs) arising in high-risk patients with or without liver cirrhosis have not been elucidated. This study aimed to compare the clinicopathologic and imaging characteristics of cHCC-CCAs in patients with or without cirrhosis and to determine the prognostic factors for recurrence-free survival (RFS) after curative resections of single cHCC-CCAs.

METHODS

This retrospective study included 113 patients with surgically resected single cHCC-CCAs who underwent preoperative magnetic resonance imaging from January 2008 to December 2019 at two tertiary referral centres. Clinical, pathologic and imaging features of tumours were compared in high-risk patients with or without cirrhosis. Imaging features were assessed using the Liver Imaging Reporting and Data System (LI-RADS) version 2018. RFS and associated factors were evaluated using Cox proportional hazards regression analysis, Kaplan-Meier analysis and log-rank test.

RESULTS

cHCC-CCAs arising from cirrhotic livers had a smaller mean tumour size (2.9 cm vs. 4.5 cm; P < .001) and were more frequently categorized as LR-5 or 4 (41.2% vs. 20.0%; P = .024) than those arising from non-cirrhotic livers. In multivariable analysis, a tumour size of > 3 cm (hazard ratio [HR], 2.081; 95% confidence interval [CI], 1.180-3.668; P = .011) and the LR-M category (HR, 2.302; 95% CI, 1.198-4.424; P = .012) were independent predictors associated with worse RFS.

CONCLUSIONS

The tumour size and distribution of LI-RADS categories of cHCC-CCAs differed in high-risk patients with or without cirrhosis. And LR-M category was a worse prognosis predictor after curative resections than LR-5 or 4 category.