Poor outcome of hepatocellular carcinoma with stemness marker under hypoxia: resistance to transarterial chemoembolization

Molecular subtyping combined with multiomics analysis to study correlation between TACE refractoriness and tumor stemness in hepatocellular carcinoma

BACKGROUND

Transarterial chemoembolization (TACE) refractoriness is a significant challenge in treating intermediate to advanced-stage hepatocellular carcinoma (HCC). A few studies suggest that liver cancer stem cells (LCSCs) may be associated with TACE refractoriness. This study aims to explore the potential correlation between TACE refractoriness and HCC stemness, highlighting its clinical significance.

METHODS

This research encompassed the analysis of diverse HCC datasets, including RNA-sequencing, microarray, single-cell RNA-sequencing, and clinical cohorts. We identified common genes between TACE refractoriness and tumor stemness (TSGs). Unsupervised clustering was employed to classify HCC patients into different clusters based on TSGs (TRS clusters). The study explored the differences in clinical prognosis, biological characteristics, genomic variations, immune landscapes, and treatment responses among the TRS clusters.

RESULTS

Patients with TACE-refractoriness demonstrated significantly higher tumor stemness. Our study identified 33 TSGs and established two TRS clusters, including C1 and C2. C1 was associated with TACE refractoriness, elevated tumor stemness, and poorer prognosis. Genomic alterations were found to be significantly different between the TRS clusters. The C1 exhibited signs of immunosuppression and lower activity of immune effector cells, while the C2 had a more robust immune response and higher level of immune cell presence. Single-cell RNA-seq revealed distinct cell type characteristics in each subtypes, with the C1 showing a higher proportion of stem cells and malignant cells.

CONCLUSION

Our findings establish a connection between TACE refractoriness and tumor stemness in HCC, proposing a novel subtype classification to guide personalized treatment. Insights gained may facilitate overcoming TACE refractoriness and the development of innovative therapies.

CK19 protein expression: the best cutoff value on the prognosis and the prognosis model of hepatocellular carcinoma

BACKGROUND AND OBJECTIVE

In clinical practice, CK19 can be an important predictor for the prognosis of HCC. Due to the high incidence and mortality rates of HCC, more effective and practical prognostic prediction models need to be developed urgently.

METHODS

A total of 1,168 HCC patients, who underwent radical surgery at the Guangxi Medical University Cancer Hospital, between January 2014 and July 2019, were recruited, and their clinicopathological data were collected. Among the clinicopathological data, the optimal cutoff value of CK19-positive HCC was determined by calculating the area under the curve (AUC) using survival analysis and time-dependent receiver operating characteristic (timeROC) curve analysis. The predictors were screened using univariate and multivariate COX regression and least absolute shrinkage and selection operator (LASSO) regression to construct nomogram prediction models, and their predictive potentials were assessed using calibration curves and AUC values.

RESULTS

The 0% positive rate of CK19 was considered the optimal cutoff value to predict the poor prognosis of CK19-positive HCC. The survival analysis of 335 CK19-positive HCC showed no significant statistical differences in the overall survival (OS) and disease-free survival (DFS) of CK19-positive HCC patients. A five-factor risk (CK19, CA125, Edmondson, BMI, and tumor number) scoring model and an OS nomograph model were constructed and established, and the OS nomograph model showed a good predictive performance and was subsequently verified.

CONCLUSION

A 0% expression level of CK19 protein may be an optimal threshold for predicting the prognosis of CK19-positive HCC. Based on this, CK19 marker a good nomogram model was constructed to predict HCC prognosis.

Serum CYFRA 21-1 and CK19-2G2 as Predictive Biomarkers of Response to Transarterial Chemoembolization in Hepatitis C-related Hepatocellular Carcinoma Among Egyptians: A Prospective Study

Background and aim

Cytokeratin 19 (CK19)-positive HCC is a subtype of hepatocellular carcinoma (HCC) with poor biological behavior and resistance to different treatments including transarterial chemoembolization (TACE). The current study aimed to investigate the predictive value of serum CK 19 fragment 21-1 (CYFRA 21-1) and serum CK 19 fragment 2G2 (CK 19-2G2) for TACE response in patients with hepatitis C virus (HCV)-related HCC.

Methods

This prospective study assessed the pretreatment serum CYFRA 21-1 and CK 19-2G2 levels in 64 patients with HCV-related naïve HCC who underwent TACE to predict 1-year overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Additionally, 40 healthy individuals were included as controls. Pretreatment alpha-fetoprotein (AFP) was also measured for comparison.

Results

After exclusions, 60 patients completed TACE sessions, and the 1-year OS was 52%, and ORR post TACE was 71.8%. HCC patients with elevated levels of CYFRA 21-1, CK 19-2G2, or baseline AFP measuring ≥400 ng/ml have decreased 1-year OS and PFS after TACE. Serum CK19-2G2 was an independent predictor of 1-year OS using multivariate hazard regression analysis. Pretreatment normal serum CYFRA 21-1 levels (P = 0.047), serum AFP measuring <400 ng/ml (P = 0.016), and lower AST (P = 0.002) were independent predictors of ORR to TACE using multivariate logistic regression analysis. The predictive ability of pretreatment elevated serum CYFRA 21-1, AFP measuring ≥400 ng/ml, AFP + CYFRA 21-1, AFP + CK 19-2G2, or AFP + CYFRA 21-1+ CK19-2G2 to predict nonresponse (progressive disease) to TACE (area under the curve = 0.795, 0.690, 0.830, 0.725, and 0.850, respectively).

Conclusions

This study demonstrated that incorporating the measurement of serum CYFRA 21-1 or CK19-2G2 levels, along with AFP, during the initial diagnosis can aid in predicting poor 1-year OS, PFS, and ORR to TACE in patients with HCV-related HCC.

Prediction of PD-L1 expression in unresectable hepatocellular carcinoma with gadoxetic acid-enhanced MRI

OBJECTIVES

To develop a model to predict programmed death-ligand 1 (PD-L1) expression in unresectable hepatocellular carcinoma (HCC) based on gadoxetic acid-enhanced magnetic resonance imaging (MRI) findings and clinical characteristics.

MATERIALS AND METHODS

We enrolled patients with unresectable HCC who underwent gadoxetic acid-enhanced MRI between January 2021 and May 2023. Immunohistochemical staining of PD-L1 was performed on a biopsy specimen. Patients with a history of any prior treatment for HCC or those lacking an MRI scan within 30 days of the biopsy date were excluded. Using the clinical and MRI findings, we developed a PD-L1 prediction score using logistic regression.

RESULTS

This study included 49 patients with HCC (median age, 64 years; interquartile range, 57-73 years; 44 men). Among these, 15 (31 %) were positive for PD-L1 expression. The PD-L1 prediction score was defined as the sum of arterial phase hypoenhancement (score 1), necrosis (score 1), and AFP >4000 ng/mL (score 2). The AUC value of the PD-L1 prediction score was 0.838 (95 % confidence interval [CI], 0.715-0.962). When the PD-L1 prediction score was ≥3, the sensitivity, specificity, and positive predictive value of PD-L1 positivity were 67 %, 91 %, and 77 %, respectively.

CONCLUSION

We developed a PD-L1 prediction score for unresectable HCC with high specificity that could potentially contribute to the identification of effective candidates for immune checkpoint inhibitors.

A nomogram for preoperative prediction of vessels encapsulating tumor clusters (VETC) pattern and prognosis of hepatocellular carcinoma

BACKGROUND

Vessels encapsulating tumor clusters (VETC) pattern of hepatocellular carcinoma (HCC) are associated with unfavorable prognosis. This study aimed to establish a nomogram model to predict VETC patterns based on preoperative CT imaging features.

PATIENTS AND METHODS

Patients who underwent surgical resection between January 1, 2016 and August 31, 2022 were retrospectively included. Predictors associated with VETC pattern were determined by using logistic regression analyses, and a nomogram model was constructed. Prognostic factors associated with recurrence-free survival (RFS) after surgical resection were identified by using Cox regression analyses.

RESULTS

A total of 84 patients were included for CT analysis. All patients underwent radical surgical resection. AST/ALT >1.07(odds ratio [OR], 4.91; 95 ​% CI: 1.11, 21.68; P ​< ​0.05), intratumoral necrosis (OR, 4.99; 95 ​% CI: 1.25, 19.99; P ​< ​0.05) and enhancing capsule (OR, 3.32; 95 ​% CI: 1.27, 8.94; P ​< ​0.05) were independent predictors of VETC pattern. These features were used for the construction of nomogram model, which showed comparable prediction performance, with AUC value of 0.767 (95%CI [0.662, 0.852]). CK19 status (Hazard ratio [HR], 2.02; 95 ​% CI: 1.06, 3.86; P ​< ​0.05), the number of tumors (HR, 3.31; 95 ​% CI: 1.47, 7.45; P ​< ​0.05) and VETC pattern (HR, 2.52; 95 ​% CI: 1.31, 4.86; P ​< ​0.05) were independent predictors of postoperative RFS.

CONCLUSION

A nomogram model based on preoperative CT imaging features could be used for the characterization of VETC pattern, and has prognostic significance for postoperative RFS in patients with HCC.

Efficacy and safety of apatinib plus immune checkpoint inhibitors and transarterial chemoembolization for the treatment of advanced hepatocellular carcinoma

PURPOSE

The evidence of apatinib plus immune checkpoint inhibitors (ICIs) and transarterial chemoembolization (TACE) for treating advanced hepatocellular carcinoma (HCC) is limited. This study aimed to compare the treatment efficacy and safety of apatinib plus ICIs and TACE with apatinib plus TACE in these patients.

METHODS

This study retrospectively enrolled 90 patients with advanced HCC treated with apatinib plus TACE (A-TACE group, n = 52) or apatinib plus ICIs and TACE (IA-TACE group, n = 38).

RESULTS

The objective response rate was numerically higher in IA-TACE group compared with A-TACE group without statistical significance (57.9% vs. 36.5%, P = 0.055). Disease control rate was not different between groups (86.8% vs. 76.9%, P = 0.248). Progression-free survival (PFS) was improved in IA-TACE group compared with A-TACE group (P = 0.018). The median PFS (95% confidence interval) was 12.5 (8.7-16.3) months in IA-TACE group and 8.5 (5.6-11.4) months in A-TACE group. Overall survival (OS) was also prolonged in IA-TACE group compared with A-TACE group (P = 0.007). The median OS (95% confidence interval) was 21.1 (15.8-26.4) months in IA-TACE group and 14.3 (11.5-17.1) months in A-TACE group. By multivariate Cox regression model, IA-TACE was independently associated with prolonged PFS (hazard ratio = 0.539, P = 0.038) and OS (hazard ratio = 0.447, P = 0.025). Most adverse events were not different between groups. Only the incidence of reactive cutaneous capillary endothelial proliferation was higher in IA-TACE group compared with A-TACE group (10.5% vs. 0.0%, P = 0.029).

CONCLUSION

Apatinib plus ICIs and TACE may be an effective and safe treatment for patients with advanced HCC, but further large-scale studies are needed for verification.

Bioinspired Tumor Calcification-Guided Early Diagnosis and Eradication of Hepatocellular Carcinoma

Tumor calcification is found to be associated with the benign prognostic, and which shows considerable promise as a somewhat predictive index of the tumor response clinically. However, calcification is still a missing area in clinical cancer treatment. A specific strategy is proposed for inducing tumor calcification through the synergy of calcium peroxide (CaO2)-based microspheres and transcatheter arterial embolization for the treatment of hepatocellular carcinoma (HCC). The persistent calcium stress in situ specifically leads to powerful tumor calcioptosis, resulting in diffuse calcification and a high-density shadow on computed tomography that enables clear localization of the in vivo tumor site and partial delineation of tumor margins in an orthotopic HCC rabbit model. This osmotic calcification can facilitate tumor clinical diagnosis, which is of great significance in differentiating tumor response during early follow-up periods. Proteome and phosphoproteome analysis identify that calreticulin (CALR) is a crucial target protein involved in tumor calcioptosis. Further fluorescence molecular imaging analysis also indicates that CALR can be used as a prodromal marker of calcification to predict tumor response at an earlier stage in different preclinical rodent models. These findings suggest that upregulated CALR in association with tumor calcification, which may be broadly useful for quick visualization of tumor response.

Molecular mechanisms of TACE refractoriness: Directions for improvement of the TACE procedure

Transcatheter arterial chemoembolisation (TACE) is the standard of care for intermediate-stage hepatocellular carcinoma and selected patients with advanced hepatocellular carcinoma. However, TACE does not achieve a satisfactory objective response rate, and the concept of TACE refractoriness has been proposed to identify patients who do not fully benefit from TACE. Moreover, repeated TACE is necessary to obtain an optimal and sustained anti-tumour response, which may damage the patient's liver function. Therefore, studies have recently been performed to improve the effectiveness of TACE. In this review, we summarise the detailed molecular mechanisms associated with TACE responsiveness and relapse after this treatment to provide more effective targets for adjuvant therapy while helping to improve TACE regimens.

A Hypoxia-Related miRNA-mRNA Signature for Predicting the Response and Prognosis of Transcatheter Arterial Chemoembolization in Hepatocellular Carcinoma

Purpose

Transcatheter arterial chemoembolization (TACE) is commonly used in the treatment of hepatocellular carcinoma (HCC). However, not all patients respond to this treatment. TACE typically leads to hypoxia in the tumor microenvironment. Therefore, we aimed to construct a prognostic model based on hypoxia-related differentially expressed microRNA (miRNAs) in hepatocellular carcinoma (HCC) and to investigate the potential target mRNAs for predicting TACE response.

Methods

The hypoxia-related miRNAs (HRMs) were identified in liver cancer cells, then global test was performed to further select the miRNAs which were associated with recurrence and vascular invasion. A prognostic model was constructed based on multivariate Cox regression analysis; qRT-PCR analysis was used to validate the differentially expressed miRNAs in HCC cell lines under hypoxic condition. We further identified the putative target genes of the miRNAs and investigate the relationship between the target genes and TACE response, immune cells infiltration.

Results

We established a HRMs prognostic model for HCC patients, containing two miRNAs (miR-638, miR-501-5p), the patients with high-HRMs score showed worse survival in discovery and validation cohort; qRT-PCR analysis confirmed that these two miRNAs are up-regulated in hepatoma cells under hypoxic condition. Furthermore, four putative target genes of these two miRNAs were identified (ADH1B, CTH, FTCD, RCL1), which were significantly associated with TACE response, immune score, immunosuppressive immune cells infiltration, PDCD1 and CTLA4.

Conclusion

The HCC-HRMs signature may be utilized as a promising prognostic factor and may have implications for guiding TACE and immune therapy.

Preoperative Locoregional Therapy May Relate with Stemness and Distinct Transitions Between Epithelial and Mesenchymal States in Hepatocellular Carcinoma

Background/Objectives

Locoregional therapy (LRT) might impel hepatocellular carcinoma (HCC) to exhibit different phenotypes by modulating tumoral cell adaptation. HCCs presurgically treated with LRT were studied, focusing on stemness and mesenchymal features.

Methods

Clinicopathological and immunohistochemical data (Ki67, p53, EpCAM, CK19, CK7, ASMA and vimentin expression) were considered in 89 HCC nodules (30 treated with LRT; 59 non-treated), comprising 46 liver transplanted/surgically resected patients.

Results

In LRT group, well and poorly differentiated tumors without fibrous encapsulation were predominant (P < 0.05) and peritumoral necroinflammation severity tended to be greater. Peritumoral Ki67 expression was higher (P < 0.05) and p53, EpCAM, CK19 and CK7 peritumoral expression was relevant after LRT, where ablated carcinomas displayed higher peritumoral CK19 expression (P < 0.05). Tumoral ASMA and vimentin expression was higher in non-LRT group (P < 0.05). In LRT group, an exclusive association between progenitor/cholangiocytic cell and mesenchymal markers expressed by tumoral cells was observed (P < 0.05): EpCAM tumoral expression associated with vimentin stromal expression; tumoral CK19 expression associated with stromal ASMA expression; tumoral CK7 expression associated with tumoral vimentin expression.

Conclusion

Peritumoral cellular proliferation and expression of progenitor/cholangiocytic cell markers seem to be more frequent after LRT, with a distinctive epithelial-mesenchymal interplay and plasticity in peritumoral and tumoral compartments.

Radiological diagnosis of hepatocellular carcinoma does not preclude biopsy before treatment

Background & Aims

The diagnosis of hepatocellular carcinoma (HCC) in patients with cirrhosis relies on non-invasive criteria based on international guidelines. The advent of systemic therapies warrants reconsideration of the role of biopsy specimens in the diagnosis of HCC. Accordingly, we investigated the diagnostic performance of the LI-RADS 2018 and the AASLD 2011 criteria.

Methods

Consecutive patients with cirrhosis who underwent a biopsy for suspected HCC between 2015 and 2020 were included. The available imaging studies (computed tomography and/or magnetic resonance imaging) were blindly reviewed by two independent radiologists. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were assessed for LI-RADS, AASLD, and biopsies.

Results

In total, 167 patients underwent both available biopsy and imaging. Of the 137 relevant biopsies, 114 patients had HCC (83.2%), 12 (9%) had non-HCC malignant lesions, and 11 (8%) had benign nodules. The PPV and NPV of the biopsies were 100% and 62%, respectively; 30 biopsies were non-contributive. The PPV and NPV of the LI-RADS categories were 89% and 32.8% for LR-5 and 85.5% and 54.5% for LR-4 + 5 + TIV, respectively. The PPV and NPV of the 2011 AASLD criteria were 93.2% and 35.6%, respectively. The interobserver kappa (k = 0.380) for the LR-5 categories was reasonable. Of 100 LR-5 nodules, 11 were misclassified, in particular one case was a colorectal metastasis, and two cases were cholangiocarcinomas, of which nine were identified through biopsy, whereas six were correctly classified according to LI-RADS (LR-M or LR-TIV). Fifty percent of macrotrabecular HCC and 48.4% of poorly differentiated HCC (Edmonson 3 and 4) were not classified as LR-5.

Conclusions

LI-RADS 2018 did not outperform the AASLD 2011 score as a non-invasive diagnosis of HCC. Tumor biopsy allowed restoration of an accurate diagnosis in 11% of LR-5 cases. A combined radiological and histological diagnosis should be considered mandatory for good treatment assessment.

Impact and Implications

Although biopsy is not required for hepatocellular carcinoma diagnosis when the LI-RADS criteria are met according to current guidelines, our study underscores the limits of radiology and the need for biopsy when hepatocellular carcinoma is suspected. Histological findings could change therapeutics of liver tumors even if only for a small proportion of patients. Histological proof of the type of cancer is a standard in oncology.

Hepatocellular carcinoma: tumor heterogeneity and recurrence after preoperative locoregional therapy

How locoregional therapy (LRT) may change tumor compositional and functional heterogeneity, consequently contributing to treatment resistance and tumor recurrence remains largely unknown. A series of hepatocellular carcinomas (HCCs) treated with preoperative locoregional therapy (LRT) that relapsed after surgery was studied. Thirty HCCs comprising 15 patients treated with LRT prior to liver transplantation (n = 14)/surgical resection (n = 1) were studied. Five patients undergoing pre-transplant LRT, comprising 11 HCCs, presented tumor recurrence (median recurrence time = 10 months). Clinicopathological data and immunoexpression of proliferation markers (Ki67, p53), cholangiocytic/hepatic progenitor cell (HPC) markers (EpCAM)/BerEp4, CK19, CK7) and mesenchymal markers (ASMA, vimentin) were evaluated in tumoral epithelial/stromal cells and in peritumoral parenchyma. Higher grading of tumor differentiation, microvascular invasion and tumoral cell p53 expression significantly associated with recurrence (p < 0.05). Piecemeal necrosis features were more frequent in tumors that recurred (p < 0,05). Tumoral and peritumoral Ki67 expression and EpCAM, CK19 and CK7 expression in tumoral cells tended to be higher in treated tumors that recurred. Peritumoral expression of cholangiocytic/HPC markers and tumoral epithelial and stromal cellular expression of mesenchymal markers tended to be higher for tumors without recurrence. Recurrence after transplant with preoperative LRT might be associated with poor HCC differentiation, higher cellular proliferation rate, peritumoral piecemeal necrosis features and cholangiocytic/HPC phenotypes. Understanding HCC progression factors after LRT might be important for optimizing patient selection for treatment, improving surveillance after LRT and to explore synergies between LRT and systemic targeted therapies to prevent recurrence.

Advances in Histological and Molecular Classification of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a primary liver cancer characterized by hepatocellular differentiation. HCC is molecularly heterogeneous with a wide spectrum of histopathology. The prognosis of patients with HCC is generally poor, especially in those with advanced stages. HCC remains a diagnostic challenge for pathologists because of its morphological and phenotypic diversity. However, recent advances have enhanced our understanding of the molecular genetics and histological subtypes of HCC. Accurate diagnosis of HCC is important for patient management and prognosis. This review provides an update on HCC pathology, focusing on molecular genetics, histological subtypes, and diagnostic approaches.

Transarterial chemoembolization for hepatocellular carcinoma: 2023 expert consensus-based practical recommendations of the Korean Liver Cancer Association

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post- procedural patient care.

Transarterial chemoembolization for hepatocellular carcinoma: 2023 Expert consensus-based practical recommendations of the Korean Liver Cancer Association

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post- procedural patient care.

Transarterial Chemoembolization for Hepatocellular Carcinoma: 2023 Expert Consensus-Based Practical Recommendations of the Korean Liver Cancer Association

Transarterial chemoembolization (TACE) was introduced in 1977 with the administration of chemotherapeutic agent to gelatin sponge particles through the hepatic artery in patients with hepatocellular carcinoma (HCC) and was established as conventional TACE using Lipiodol in the 1980s. In the 2000s, drug-eluting beads were developed and applied clinically. Currently, TACE is a commonly used non-surgical treatment modality for patients with HCC who are unsuitable for curative treatment. Considering the vital role of TACE in the management of HCC, it is crucial to organize current knowledge and expert opinions regarding patient preparation, procedural techniques, and post-treatment care in TACE, which can enhance therapeutic efficacy and safety. A group of 12 experts in the fields of interventional radiology and hepatology, convened by the Research Committee of the Korean Liver Cancer Association (KLCA), has developed expert consensus-based practical recommendations in TACE. These recommendations have been endorsed by the Korean Society of Interventional Radiology and provide useful information and direction in performing TACE procedure as well as pre- and post-procedural patient care.

Hepatocellular Carcinoma's Molecular Markers: The New Trend as Diagnostic/Prognostic Markers!

Hepatocellular carcinoma represents one of the serious and common liver diseases that need to be early diagnosed and promptly treated; Hence various researchers have paid great attention to the utility of molecular markers in the diagnosis and/or prognosis of hepatic neoplasms. Our letter focused on summarizing their role as diagnostic/prognostic tools in patients with hepatocellular tumours for a better outcome.Image 1.

To be or not to be: The double-edged sword roles of liver progenitor cells

Given the liver's remarkable and unique regenerative capacity, researchers have long focused on liver progenitor cells (LPCs) and liver cancer stem cells (LCSCs). LPCs can differentiate into both hepatocytes and cholangiocytes. However, the mechanism underlying cell conversion and its distinct contribution to liver homeostasis and tumorigenesis remain unclear. In this review, we discuss the complicated conversions involving LPCs and LCSCs. As the critical intermediate state in malignant transformation, LPCs play double-edged sword roles. LPCs are not only involved in hepatic wound-healing responses by supplementing liver cells and bile duct cells in the damaged liver but may transform into LCSCs under dysregulation of key signaling pathways, resulting in refractory malignant liver tumors. Because LPC lineages are temporally and spatially dynamic, we discuss crucial LPC subgroups and summarize regulatory factors correlating with the trajectories of LPCs and LCSCs in the liver tumor microenvironment. This review elaborates on the double-edged sword roles of LPCs to help understand the liver's regenerative potential and tumor heterogeneity. Understanding the sources and transformations of LPCs is essential in determining how to exploit their regenerative capacity in the future.

Comparison of imaging findings of macrotrabecular-massive hepatocellular carcinoma using CT and gadoxetic acid-enhanced MRI

OBJECTIVES

To investigate the imaging findings of macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) on CT and MRI, and examine their diagnostic performance and prognostic significance.

METHODS

We retrospectively enrolled 220 consecutive patients who underwent hepatic resection between June 2009 and December 2013 for single treatment-naïve HCC, who have preoperative CT and gadoxetic acid-enhanced MRI. Independent reviews of histopathology and imaging were performed by two reviewers. Previously reported imaging findings, LI-RADS category, and CT attenuation of MTM-HCC were investigated. The diagnostic performance of the MTM-HCC diagnostic criteria was compared across imaging modalities.

RESULTS

MTM-HCC was associated with ≥ 50% arterial phase hypovascular component, intratumoral artery, arterial phase peritumoral enhancement, and non-smooth tumor margin on CT and MRI (p < .05). Arterial phase hypovascular components were less commonly observed on MRI subtraction images than on CT or MRI, while non-rim arterial phase hyperenhancement and LR-5 were more commonly observed on MRI subtraction images than on MRI (p < .05). MTM-HCC showed lower tumor attenuation in the CT arterial phase (p = .01). Rhee's criteria, defined as ≥ 50% hypovascular component and ≥ 2 ancillary findings (intratumoral artery, arterial phase peritumoral enhancement, and non-smooth tumor margin), showed similar diagnostic performance for MRI (sensitivity, 41%; specificity, 97%) and CT (sensitivity, 31%; specificity, 94%). Rhee's criteria on CT were independent prognostic factors for overall survival.

CONCLUSION

The MRI diagnostic criteria for MTM-HCC are applicable on CT, showing similar diagnostic performance and prognostic significance. For MTM-HCC, arterial phase subtraction images can aid in the HCC diagnosis by depicting subtle arterial hypervascularity.

KEY POINTS

• MTM-HCC on CT demonstrated previously described MRI findings, including arterial phase hypovascular component, intratumoral artery, arterial phase peritumoral enhancement, and necrosis. • The MRI diagnostic criteria for MTM-HCC were also applicable to CT, showing comparable diagnostic performance and prognostic significance. • On arterial phase subtraction imaging, MTM-HCC more frequently demonstrated non-rim enhancement and LR-5 and less frequently LR-M than MRI arterial phase, which may aid in the diagnosis of HCC.

SLC-0111, an inhibitor of carbonic anhydrase IX, attenuates hepatoblastoma cell viability and migration

Background

In response to hypoxia, tumor cells undergo transcriptional reprogramming including upregulation of carbonic anhydrase (CA) IX, a metalloenzyme that maintains acid-base balance. CAIX overexpression has been shown to correlate with poor prognosis in various cancers, but the role of this CA isoform in hepatoblastoma (HB) has not been examined.

Methods

We surveyed the expression of CAIX in HB specimens and assessed the impact of SLC-0111, a CAIX inhibitor, on cultured HB cells in normoxic and hypoxic conditions.

Results

CAIX immunoreactivity was detected in 15 out of 21 archival pathology HB specimens. The CAIX-positive cells clustered in the middle of viable tumor tissue or next to necrotic areas. Tissue expression of CAIX mRNA was associated with metastasis and poor clinical outcome of HB. Hypoxia induced a striking upregulation of CAIX mRNA and protein in three HB cell models: the immortalized human HB cell line HUH6 and patient xenograft-derived lines HB-295 and HB-303. Administration of SLC-0111 abrogated the hypoxia-induced upregulation of CAIX and decreased HB cell viability, both in monolayer and spheroid cultures. In addition, SLC-0111 reduced HB cell motility in a wound healing assay. Transcriptomic changes triggered by SLC-0111 administration differed under normoxic vs. hypoxic conditions, although SLC-0111 elicited upregulation of several tumor suppressor genes under both conditions.

Conclusion

Hypoxia induces CAIX expression in HB cells, and the CAIX inhibitor SLC-0111 has in vitro activity against these malignant cells.

Vessels That Encapsulate Tumor Clusters (VETC) Predict cTACE Response in Hepatocellular Carcinoma

Background

To investigate the correlation between hepatocellular carcinoma (HCC) pathological types and conventional transarterial chemoembolization (cTACE), and to evaluate the predictive value of the pathological types for efficacy of cTACE.

Methods

We investigated 186 naive HCC patients from 2 hospitals, including 63 patients with recurrence after surgical resection, and 123 unresectable cases, who underwent at least one cTACE procedure as the first treatment. All patients were histologically diagnosed with HCC by surgical resection and/or liver biopsy. Lipiodol deposition rate, ORR (objective response rate), PFS (progression-free survival), OS (overall survival) were compared among different HCC pathological types.

Results

This study evaluated 186 naive HCC patients and 189 tumor nodules. Vessels that encapsulate tumor clusters (VETC), macrotrabecular-massive (MTM), CK19-positive types were identified in 38% (72/189), 40% (76/189), and 28% (53/189) of the whole cohort, respectively. VETC, MTM and CK19-negative HCCs derived significantly better lipiodol deposition rate and ORR. cTACE prolonged the PFS of VETC and CK19-negative HCCs compared with non-VETC and CK19-positive HCCs in the recurrence, liver biopsy and combining whole cohorts, whereas the OSs of different pathological types were not significantly different. Multivariate analysis showed that VETC (OR, 4.671, 95% CI [1.954, 11.166], P<0.001) and CK19-positive type (OR, 0.127, 95% CI [0.044, 0.362], P<0.001) were independent predictive factors for the first cTACE response. However, only VETC type was significantly associated with the second cTACE response in multivariate analysis (OR, 3.31, 95% CI [1.24, 8.83], P=0.017), suggesting that VETC might be a more useful predictor of cTACE response.

Conclusion

Our study suggests that VETC is an effective predictor of cTACE response in patients with HCC.

Understanding the versatile roles and applications of EpCAM in cancers: from bench to bedside

Epithelial cell adhesion molecule (EpCAM) functions not only in physiological processes but also participates in the development and progression of cancer. In recent decades, extensive efforts have been made to decipher the role of EpCAM in cancers. Great advances have been achieved in elucidating its structure, molecular functions, pathophysiological mechanisms, and clinical applications. Beyond its well-recognized role as a biomarker of cancer stem cells (CSCs) or circulating tumor cells (CTCs), EpCAM exhibits novel and promising value in targeted therapy. At the same time, the roles of EpCAM in cancer progression are found to be highly context-dependent and even contradictory in some cases. The versatile functional modules of EpCAM and its communication with other signaling pathways complicate the study of this molecule. In this review, we start from the structure of EpCAM and focus on communication with other signaling pathways. The impacts on the biology of cancers and the up-to-date clinical applications of EpCAM are also introduced and summarized, aiming to shed light on the translational prospects of EpCAM.

Differential expression of hepatic cancer stemness and hypoxia markers in residual cancer after locoregional therapies for hepatocellular carcinoma

Transarterial chemoembolization (TACE) and transarterial radioembolization (TARE) treatment to hepatocellular carcinoma (HCC) are effective tools to control tumor growth, prolong survival, palliate symptoms, and improve quality of life for patients with intermediate-stage HCC. Nevertheless, there is high variability of local HCC responses to locoregional therapies; therefore, better and personalized prediction of tumor response to TACE is necessary for management of patients with HCC, especially when these modalities of treatment are used to bridge patients for liver transplant. Here, we investigated differential expression of hepatic cancer stem cell and hypoxia in residual HCC after TACE treatment in comparison with TARE. A publicly available gene data set was screened for differentially expressed genes (DEGs) in TACE_Response compared with TACE_Non-response HCC. Analysis of the GSE104580 data set displayed a total of 406 DEGs, including 196 down-regulated and 210 up-regulated DEGs. Of the 196 down-regulated DEGs, three hepatic cancer stem cell (CSC) markers and 11 hypoxia-related genes were identified. Immunohistochemical staining of hepatic CSC and hypoxia markers on explant liver tissues exhibited more intense positive staining of hepatic CSC markers (CD24, EpCAM) and hypoxia marker carbonic anhydrase 9 (CA9) in residual tumor nodule from patients with HCC treated with TACE compared with nontreated patients. Furthermore, Pearson's correlation analysis revealed the significant correlation between hepatic CSC markers and hypoxia marker, CA9. Conclusion: Hepatic CSC and hypoxia markers predict nonresponse to TACE and are differentially expressed in residual tumor after TACE compared with TARE. In the long term, TACE-induced hypoxia may select an aggressive HCC phenotype.

Ultrasomics prediction for cytokeratin 19 expression in hepatocellular carcinoma: A multicenter study

Objective

The purpose of this study was to investigate the preoperative prediction of Cytokeratin (CK) 19 expression in patients with hepatocellular carcinoma (HCC) by machine learning-based ultrasomics.

Methods

We retrospectively analyzed 214 patients with pathologically confirmed HCC who received CK19 immunohistochemical staining. Through random stratified sampling (ratio, 8:2), patients from institutions I and II were divided into training dataset (n = 143) and test dataset (n = 36), and patients from institution III served as external validation dataset (n = 35). All gray-scale ultrasound images were preprocessed, and then the regions of interest were then manually segmented by two sonographers. A total of 1409 ultrasomics features were extracted from the original and derived images. Next, the intraclass correlation coefficient, variance threshold, mutual information, and embedded method were applied to feature dimension reduction. Finally, the clinical model, ultrasonics model, and combined model were constructed by eXtreme Gradient Boosting algorithm. Model performance was assessed by area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy.

Results

A total of 12 ultrasomics signatures were used to construct the ultrasomics models. In addition, 21 clinical features were used to construct the clinical model, including gender, age, Child-Pugh classification, hepatitis B surface antigen/hepatitis C virus antibody (positive/negative), cirrhosis (yes/no), splenomegaly (yes/no), tumor location, tumor maximum diameter, tumor number, alpha-fetoprotein, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, glutamyl-transpeptidase, albumin, total bilirubin, conjugated bilirubin, creatinine, prothrombin time, fibrinogen, and international normalized ratio. The AUC of the ultrasomics model was 0.789 (0.621 – 0.907) and 0.787 (0.616 – 0.907) in the test and validation datasets, respectively. However, the performance of the combined model covering clinical features and ultrasomics signatures improved significantly. Additionally, the AUC (95% CI), sensitivity, specificity, and accuracy were 0.867 (0.712 – 0.957), 0.750, 0.875, 0.861, and 0.862 (0.703 – 0.955), 0.833, 0.862, and 0.857 in the test dataset and external validation dataset, respectively.

Conclusion

Ultrasomics signatures could be used to predict the expression of CK19 in HCC patients. The combination of clinical features and ultrasomics signatures showed excellent effects, which significantly improved prediction accuracy and robustness.

The dual role of transforming growth factor-beta signatures in human B viral multistep hepatocarcinogenesis: early and late responsive genes

Background/Aim

Transforming growth factor-beta (TGF-β) has a dichotomous role, functioning as a tumor suppressor and tumor promoter. TGF-β signatures, explored in mouse hepatocytes, have been reported to predict the clinical outcomes of hepatocellular carcinoma (HCC) patients; HCCs exhibiting early TGF-β signatures showed a better prognosis than those with late TGF-β signatures. The expression status of early and late TGF-β signatures remains unclear in defined lesions of human B-viral multistep hepatocarcinogenesis.

Methods

The expression of TGF-β signatures, early and late responsive signatures of TGF-β were investigated and analyzed for their correlation in cirrhosis, low-grade dysplastic nodules (DNs), high-grade DNs, early HCCs and progressed HCCs (pHCCs) by real-time PCR and immunohistochemistry.

Results

The expression levels of TGF-β signaling genes (TGFB1, TGFBR1, TGFBR2 and SMAD4) gradually increased with the progression of hepatocarcinogenesis, peaking in pHCCs. The expression of early responsive genes of TGF-β (GADD45B, FBP1, CYP1A2 and CYP3A4) gradually decreased, and that of the late TGF-β signatures (TWIST and SNAI1) significantly increased according to the progression of multistep hepatocarcinogenesis. Furthermore, mRNA levels of TWIST and SNAI1 were well correlated with those of stemness markers, with upregulation of TGF-β signaling, whereas FBP1 expression was inversely correlated with that of stemness markers.

Conclusions

The enrichment of the late responsive signatures of TGF-β with induction of stemness is considered to be involved in the progression of the late stage of multistep hepatocarcinogenesis, whereas the early responsive signatures of TGF-β are suggested to have tumor-suppressive roles in precancerous lesions of the early stage of multistep hepatocarcinogenesis.

Etiology, Pathogenesis, Diagnosis, and Practical Implications of Hepatocellular Neoplasms

Hepatocellular carcinoma (HCC), a major global contributor of cancer death, usually arises in a background of chronic liver disease, as a result of molecular changes that deregulate important signal transduction pathways. Recent studies have shown that certain molecular changes of hepatocarcinogenesis are associated with clinicopathologic features and prognosis, suggesting that subclassification of HCC is practically useful. On the other hand, subclassification of hepatocellular adenomas (HCAs), a heterogenous group of neoplasms, has been well established on the basis of genotype–phenotype correlations. Histologic examination, aided by immunohistochemistry, is the gold standard for the diagnosis and subclassification of HCA and HCC, while clinicopathologic correlation is essential for best patient management. Advances in clinico-radio-pathologic correlation have introduced a new approach for the diagnostic assessment of lesions arising in advanced chronic liver disease by imaging (LI-RADS). The rapid expansion of knowledge concerning the molecular pathogenesis of HCC is now starting to produce new therapeutic approaches through precision oncology. This review summarizes the etiology and pathogenesis of HCA and HCC, provides practical information for their histologic diagnosis (including an algorithmic approach), and addresses a variety of frequently asked questions regarding the diagnosis and practical implications of these neoplasms.

Mechanism of cancer stemness maintenance in human liver cancer

Primary liver cancer mainly includes the following four types: hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), hepatoblastoma (HB), and combined hepatocellular carcinoma and cholangiocarcinoma (cHCC-CCA). Recent studies have indicated that there are differences in cancer stem cell (CSC) properties among different types of liver cancer. Liver cancer stem cells (LCSCs), also called liver tumor-initiating cells, have been viewed as drivers of tumor initiation and metastasis. Many mechanisms and factors, such as mitophagy, mitochondrial dynamics, epigenetic modifications, the tumor microenvironment, and tumor plasticity, are involved in the regulation of cancer stemness in liver cancer. In this review, we analyze cancer stemness in different liver cancer types. Moreover, we further evaluate the mechanism of cancer stemness maintenance of LCSCs and discuss promising treatments for eradicating LCSCs.

Parafibromin Is Highly Expressed in Hepatocellular Carcinoma and Its Expression Correlates with Poor Prognosis

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. Much progress has been made regarding the understanding of hepatocarcinogenesis, yet the long-term survival rate of HCC patients remains poor. Recent efforts have shown parafibromin has a pathologic role in many human cancers, but little is known about the effects of parafibromin in HCC. This study aimed to investigate the pattern of parafibromin expression and its clinicopathologic significance in human HCC. Immunohistochemical analysis of HCC and matched non-tumor liver tissues from 50 HCC patients showed that the nuclear expression of parafibromin was higher in HCC tissues (50/50 cases) than in non-tumor liver tissues (17/50 cases). Moreover, elevated parafibromin expression was found to be significantly correlated with the presence of microvascular invasion (p = 0.017), hepatitis virus infection-induced occurrence (p = 0.005), and poorer tumor differentiation (Edmondson-Steiner grade; p = 0.000). Kaplan-Meier analysis showed that HCC patients with elevated parafibromin expression had poorer recurrence-free (p = 0.014, log-rank test = 6.079) and overall survival (p = 0.036, log-rank test = 4.414). These findings indicate parafibromin may be related to the pathogenesis of HCC and a potential prognostic marker for HCC patients after hepatectomy.

Repeated loco-regional therapies for hepatocellular carcinoma is associated with inferior outcome after living donor liver transplantation in cirrhotic patients

BACKGROUND

Liver transplantation is the definitive treatment for defined stage hepatocellular carcinoma (HCC) in cirrhotic patients. Loco-regional therapy (LRT) may be considered before transplantation to prevent the disease progression and the patient from dropping out of the waiting list. This study aims to evaluate the impact of repeated pretransplant LRTs on the long-term outcomes in HCC liver transplant recipients.

METHODS

Between 2004 and 2019, living donor liver transplantation (LDLT) recipients with viable HCC on the explant livers were enrolled. Uni- and multivariate analysis was performed with the Cox regression model to stratify the risk factors associated with HCC recurrence and patent survival after LDLT.

RESULTS

A total of 124 patients were enrolled, in which 65.3% (n = 81) were Barcelona Clinic Liver Cancer classification stage B or D and 89% (n = 110) had advanced fibrosis or cirrhosis on the explanted livers. After a median follow-up of 41 months (IQR: 24-86.5), there were 18 cases (13.7%) of HCC recurrence. Univariate analysis showed that the model of end-stage liver disease and Child-Turcotte-Pugh score, pretransplant alpha-fetoprotein value (>500 ng/ml), repeated pretransplant LRTs (N > 4), increased tumor numbers and maximal size, presence of microvascular invasion, and the histological grading of the tumors are risk factors of inferior outcomes. In multivariate analysis, only repeated pretransplant LRTs (N > 4) had a significant impact on both the overall- and recurrence-free survival. The impact of pretransplant LRT was consistently significant among subgroups based on their LRT episodes (N = 0, 1-4, >4 respectively).

CONCLUSION

Repeated LRT for HCC can be associated with the risk of tumor recurrence and inferior patient survival after LDLT in cirrhotic patients. Early referral of those eligible for transplantation may improve the treatment outcomes in these patients.

Drug-eluting bead transarterial chemoembolization (TACE) exhibits superior efficacy and equal tolerance to conventional TACE in hepatocellular carcinoma patients with conventional TACE history

OBJECTIVE

Multiple conventional transarterial chemoembolization (cTACE) procedures would cause treatment resistance in hepatocellular carcinoma (HCC) patients, whether drug-eluting bead transarterial chemoembolization (DEB-TACE) would resolve this issue is a necessary topic. Thus, this study aimed to compare the efficacy and safety between DEB-TACE and cTACE in HCC patients with cTACE treatment history.

METHODS

Totally, 134 HCC patients with cTACE treatment history were retrospectively reviewed. They were categorized into DEB-TACE group (N = 70) and cTACE group (N = 64) based on the current treatment they received.

RESULTS

After 1-month treatment, DEB-TACE group exhibited an elevated objective response rate (ORR) (71.9% vs. 47.3%, P = 0.008) while similar disease control rate (DCR) (93.0% vs. 81.8%, P = 0.074) compared to cTACE group. Besides, after 3-month treatment, DEB-TACE group also displayed higher ORR (68.4% vs. 44.1%, P = 0.038) and DCR (81.6% vs. 58.8%, P = 0.034) compared to cTACE group. Furthermore, the median progression-free survival (PFS) (11.5 months vs. 6.5 months P = 0.014) and overall survival (OS) (18.5 months vs. 13.0 months, P = 0.025) were longer in DEB-TACE group compared to cTACE group. Moreover, DEB-TACE (vs. cTACE) independently correlated with prolonged PFS (P = 0.021) and OS (P = 0.017) after adjustment by multivariate Cox's regression. Besides, most of liver function indexes were similar before and after treatment between these two groups. Also, the commonly observed adverse events were pain, fever, nausea/vomiting and blood pressure elevation with similar incidence between these two groups (all P > 0.050).

CONCLUSION

DEB-TACE exhibits superiority over cTACE in HCC patients with cTACE treatment history.

The Expression and Prognostic Value of Cancer Stem Cell Markers, NRF2, and Its Target Genes in TAE/TACE-Treated Hepatocellular Carcinoma

Background and Objectives: Activation of NRF2, a key transcription factor of cytoprotectant against oxidative stress, and its target genes are associated with aggressive tumor progression, metastasis and poor survival. In addition, NRF2 signaling mediates cancer stem cell (CSC)-like properties in hepatocellular carcinoma (HCC) cells. Moreover, CSCs have been associated with HCC onset and unfavorable prognosis. Transcatheter arterial embolization (TAE) and/or transcatheter arterial chemoembolization (TACE), which attempt to restrict blood supply to diminish tumor growth, can create a hypoxic environment. However, its effect on NRF2 signaling and CSC marker CD133 in the context of prognosis of HCCs have not been investigated. Therefore, we studied the possible role of the expressions of NRF2, its target genes and CSC markers CD133 and EpCAM on the survival of HCC patients after TAE/TACE. Materials and Methods: RT-qPCR was performed with 120 tumor (T) and adjacent tumor (N) tissue pairs. Expression of a single marker or combination was assessed for associations with survival of HCC patients after TAE/TACE. Results: The result of multivariate Cox regression showed that vascular invasion (HR, 1.821; p = 0.015), metastasis (HR, 2.033; p = 0.049) and CD133 overexpression (HR, 2.013; p = 0.006) were associated with poor survival. In a Kaplan–Meier survival analysis, patients with high expression of CD133 had shorter overall survival (OS) than those with low expression of CD133 in post-TAE/TACE HCC (p < 0.001). In contrast, neither NRF2 nor components of its signaling pathway correlated with survival. Combination marker analysis showed that co-expression of NQO1 and CD133 was associated with poor outcome. Conclusions: This study suggests that analyzing the expression status of CD133 alone and co-expression of NQO1 and CD133 may have additional value in predicting the outcome of TAE/TACE-treated HCC patients.

A 10-Gene Signature Identified by Machine Learning for Predicting the Response to Transarterial Chemoembolization in Patients with Hepatocellular Carcinoma

Background

Transarterial chemoembolization (TACE) is recommended for intermediate-stage HCC patients. Owing to substantial variation in its efficacy, indicators of patient responses to TACE need to be determined.

Methods

A Gene Expression Omnibus (GEO) dataset consisting of patients of different TACE-response status was retrieved. Differentially expressed genes (DEGs) were calculated and variable gene ontology analyses were conducted. Potential drugs and response to immunotherapy were predicted using multiple bioinformatic algorithms. We built and compared 5 machine-learning models with finite genes to predict patients' response to TACE. The model was also externally validated to discern different survival outcomes after TACE. Tumor-infiltrating lymphocytes (TILs) and tumor stemness index were evaluated to explore potential mechanism of our model.

Results

The gene set variation analysis revealed enhanced pathways related to G2/M checkpoint, E2F, mTORC1, and myc in TACE nonresponders. TACE responders had better immunotherapy response too. 373 DEGs were detected and the upregulated DEGs in nonresponders were enriched in IL-17 signal pathway. 5 machine-learning models were constructed and evaluated, and a linear support vector machine (SVM)-based model with 10 genes was selected (AQP1, FABP4, HERC6, LOX, PEG10, S100A8, SPARCL1, TIAM1, TSPAN8, and TYRO3). The model achieved an AUC and accuracy of 0.944 and 0.844, respectively, in the development cohort. In the external validation cohort comprised of patients receiving adjuvant TACE and postrecurrence TACE treatment, the predicted response group significantly outlived the predicted nonresponse counterparts. TACE nonresponders tend to have more macrophage M0 cells and lower resting mast cells in the tumor tissue and the stemness index is also higher than responders. Those characteristics were successfully captured by our model.

Conclusion

The model based on expression data of 10 genes could potentially predict HCC patients' response and prognosis after TACE treatment. The discriminating power was TACE-specific.

Autophagy-Induced HDAC6 Activity During Hypoxia Regulates Mitochondrial Energy Metabolism Through the β-Catenin/COUP-TFII Axis in Hepatocellular Carcinoma Cells

Hypoxia is one of the main driving forces that results in poor outcomes and drug resistance in hepatocellular carcinoma (HCC). As the critical cellular oxygen sensor, mitochondria respond to hypoxic stress by sending retrograde signals to the nucleus that initiate adaptive metabolic responses and maintain the survival of HCC cells. Increasing evidence suggested autophagy contributes to sustain mitochondrial metabolic and quality control. Understanding how mitochondria communicate with the nucleus and alter transcription may provide promising targets for HCC treatment. In this study, we found mitochondrial undergoes selective degradation by autophagy under hypoxia. Furthermore, autophagy-activated HDAC6 not only promoted the nuclear translocation of β-catenin but also increased the affinity of β-catenin to the transcription repressor chicken ovalbumin upstream promoter-transcription factor 2 (COUP-TF II), which suppressed mitochondrial oxidative phosphorylation-related genes transcription. Our data showed that autophagy served as a critical mediator of integrating mitochondrial energy metabolism and nuclear transcription. HDAC6 may be a potential target for reducing the survival of HCC cells by interrupting mitochondria-nucleus crosstalk.

Circulating Tumor Cells in Hepatocellular Carcinoma: A Comprehensive Review and Critical Appraisal

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm and a major cause of cancer-related death worldwide. There is no ideal biomarker allowing early diagnosis of HCC and tumor surveillance in patients receiving therapy. Liquid biopsy, and particularly circulating tumor cells (CTCs), have emerged as a useful tool for diagnosis and monitoring therapeutic responses in different tumors. In the present manuscript, we evaluate the current evidence supporting the quantitative and qualitative assessment of CTCs as potential biomarkers of HCC, as well as technical aspects related to isolation, identification, and classification of CTCs. Although the dynamic assessment of CTCs in patients with HCC may aid the decision-making process, there are still many uncertainties and technical caveats to be solved before this methodology has a true impact on clinical practice guidelines. More studies are needed to identify the optimal combination of surface markers, to increase the efficiency of ex-vivo expansion of CTCs, or even to target CTCs as a potential therapeutic strategy to prevent HCC recurrence after surgery or to hamper tumor progression and extrahepatic spreading.

[Up-to-date Knowledge on the Pathological Diagnosis of Hepatocellular Carcinoma]

Hepatocellular carcinoma (HCC) has heterogeneous molecular and pathological features and biological behavior. Large-scale genetic studies of HCC were accumulated, and a pathological-molecular classification of HCC was proposed. Approximately 35% of HCCs can be classified into distinct histopathological subtypes according to their molecular characteristics. Among recently identified subtypes, macrotrabecular massive HCC, neutrophil-rich HCC, vessels encapsulating tumor clusters HCC, and progenitor phenotype HCC (HCC with CK19 expression) are associated with a poor prognosis, whereas the lymphocyte-rich HCC subtype is related to a better prognosis. This review provides up-to-date knowledge on the pathological diagnosis of HCC according to the updated World Health Organization Classification of Digestive System Tumors 5th ed.

miR-130-3p Promotes MTX-Induced Immune Killing of Hepatocellular Carcinoma Cells by Targeting EPHB4

The vast majority of primary hepatocellular cancer is hepatocellular carcinomas (HCCs). Currently, HCC is one of the more common cancers in humans, and it has a high mortality and disability rate. Mitoxantrone (MTX) is an antitumor drug that can block type II topoisomerase. It has been reported that immunogenic cell death evoked by MTX can induce the discharge of damage associated with molecular patterns (DAMPs) and subsequently influence immune cell infiltration in the tumor microenvironment. High mobilities aggregation box 1 (HMGB1) is the prototypical extracellular DAMP. Many cellular processes have been reported to involve EPHB4 receptor tyrosine kinases, but the relation of DAMP and EPHB4 is uncertain. In this research, we assessed the impact of miR-130-3p by Edu incorporation test on cell proliferation, and we have proven its impact on HCC cell migration through Transwell and wound healing tests. Flow cytometry was applied to study its influence on apoptosis. Luciferase report test was integrated in detecting the miR-130-3p target gene. The influence of miR-130-3p on the manifestation of classical DAMPs was studied, such as HMGB1, ATP, and Calreticulin. A coculture experiment was carried out to further confirm its effects on immune cell infiltration. The result displayed that miR-130-3p overexpression considerably facilitates apoptosis and suppresses the migration or proliferation of HCC cells. EPHB4 was confirmed as the target gene of miR-130-3p. Overexpression of this target gene promotes emission of Calreticulin, ATP, and HMGB1 and subsequently promotes DCs maturation and proliferation of CD4+ T cells. In summary, our results demonstrated that miR-130-3p inhibits HCC cell proliferation and migration by targeting EPHB4 and promotes drug-induced immunogenic cell death.

Multifunctional Microspheres Dual-Loaded with Doxorubicin and Sodium Bicarbonate Nanoparticles to Introduce Synergistic Trimodal Interventional Therapy

Lactic acid in the tumor microenvironment is highly correlated with the prognosis of tumor chemoembolization, but there are limited clinical strategies to deal with it. To improve the efficacy, NaHCO₃ nanoparticles are innovatively introduced into drug-loaded microspheres to neutralize lactic acid in the tumor microenvironment. Here we showed that multifunctional ethyl cellulose microspheres dual-loaded with doxorubicin (DOX) and NaHCO₃ nanoparticles (DOX/NaHCO₃-MS) presented excellent antitumor effects by improving the pH of the tumor microenvironment. The homeostasis of the tumor microenvironment was continuously disturbed due to the sustained release of NaHCO₃ nanoparticles, which also led to a significant increase in tumor cell apoptosis (compared with the control and DOX-MS groups). We also showed that the administration of DOX/NaHCO₃-MS via the hepatic artery in a rabbit model of VX2 orthotopic liver cancer resulted in optimal antitumor efficacy, and the area of tumor necrosis at the embolization site was significantly increased and the proliferation of tumor cells was significantly weakened. The designed DOX/NaHCO₃-MS exhibited strong synergistic antitumor effects of embolization, chemotherapy, and tumor microenvironment improvement. The present microspheres provided a strategy for the enhancement of the chemoembolization of hepatocellular carcinoma, which could also be extended to other clinical embolization treatments for blood-rich solid tumors.

The Clinicopathological Significance of YAP/TAZ Expression in Hepatocellular Carcinoma with Relation to Hypoxia and Stemness

Background/Aims: Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) activation has been implicated in hepatocarcinogenesis and hepatic progenitor cell differentiation, and hypoxia has been shown to induce nuclear translocation of YAP in cancer cells. Here, we aimed to investigate the relationship between hypoxia, YAP and TAZ expression and stemness-related marker expression in human hepatocellular carcinomas (HCCs) and its clinical implications.

Methods: Immunohistochemical stains were performed on tissue microarrays from 305 surgically resected HCCs, and the expression status of YAP and TAZ were correlated with CAIX, stemness markers (K19, EpCAM) and epithelial-mesenchymal transition (EMT)-related markers (uPAR, ezrin). The clinicopathological significance of YAP/TAZ expression was analyzed with relation to CAIX expression status.

Results: YAP and TAZ expression were seen in 13.4 and 4.3% of HCCs, respectively. YAP/TAZ-positive HCCs frequently demonstrated higher serum AFP levels, microvascular invasion, advanced tumor stage, increased proliferative activity and expression of stemness- and EMT-related markers, CAIX, p53 and Smad2/3 (p < 0.05, all). Interestingly, YAP/TAZ-positivity was associated with microvascular invasion, higher serum AFP levels, stemness and EMT-related marker expression only in tumors expressing CAIX (p < 0.05, all), while these associations were not seen in CAIX-negative HCCs.

Conclusions: YAP/TAZ expression is associated with vascular invasion, stemness and EMT in HCCs with hypoxia marker expression. The effect of Hippo signaling pathway deregulation in HCC may depend on the presence or absence of a hypoxic microenvironment, and hypoxia marker expression status should be taken into account when considering the use of YAP/TAZ as markers of aggressive biologic behavior in HCC.

Clinico-Radio-Pathological and Molecular Features of Hepatocellular Carcinomas with Keratin 19 Expression

Hepatocellular carcinoma (HCC) is a heterogeneous neoplasm, both from the molecular and histomorphological aspects. One example of heterogeneity is the expression of keratin 19 (K19) in a subset (4-28%) of HCCs. The presence of K19 expression in HCCs has important clinical implications, as K19-positive HCCs have been associated with aggressive tumor biology and poor prognosis. Histomorphologically, K19-positive HCCs demonstrate a more infiltrative appearance, poor histological differentiation, more frequent vascular invasion, and more intratumoral fibrous stroma than K19-negative conventional HCCs. From the molecular aspect, K19-positive HCCs have been matched with various gene signatures that have been associated with stemness and poor prognosis, including the G1-3 groups, S2 class, cluster A, proliferation signature, and vascular invasion signature. K19-positive HCCs also show upregulated signatures related to transforming growth factor-β pathway and epithelial-to-mesenchymal transition. The main regulators of K19 expression include hepatocyte growth factor-MET paracrine signaling by cancer-associated fibroblast, epidermal growth factor-epidermal growth factor receptor signaling, laminin, and DNA methylation. Clinically, higher serum alpha-fetoprotein levels, frequent association with chronic hepatitis B, more invasive growth, and lymph node metastasis have been shown to be characteristics of K19-positive HCCs. Radiologic features including atypical enhancement patterns, absence of tumor capsules, and irregular tumor margins can be a clue for K19-positive HCCs. From a therapeutic standpoint, K19-positive HCCs have been associated with poor outcomes after curative resection or liver transplantation, and resistance to systemic chemotherapy and locoregional treatment, including transarterial chemoembolization and radiofrequency ablation. In this review, we summarize the currently available knowledge on the clinico-radio-pathological and molecular features of K19-expressing HCCs, including a detailed discussion on the regulation mechanism of these tumors.

The Clinicopathological and Prognostic Significance of Nrf2 and Keap1 Expression in Hepatocellular Carcinoma

Nuclear factor E2-related factor2 (Nrf2) activation is associated with both cytoprotective effects and malignant behavior of cancer cells. This study aimed to evaluate the clinicopathological implications of the expression of Nrf2, pNrf2, and its regulator Keap1 in human hepatocellular carcinomas (HCCs). Tissue microarrays consisting of 285 surgically resected HCCs were immunohistochemically stained with pNrf2, Nrf2, Keap1, stemness-related markers (keratin 19 (K19), epithelial cell adhesion molecule (EpCAM)), carbonic anhydrase IX (CAIX), epithelial–mesenchymal transition (EMT)-related markers (ezrin, uPAR, E-cadherin), and p53, and the results were correlated with the clinicopathological features. pNrf2 expression was significantly associated with increased proliferative activity, as well as EpCAM, ezrin, p53, and CAIX expression and E-cadherin loss (p < 0.05, all). Strong cytoplasmic Nrf2 expression was associated with CAIX and ezrin expression (p < 0.05, both). Keap1 was associated with increased proliferative activity, portal vein invasion, EMT-related markers, and p53 expression in CAIX-negative HCCs (p < 0.05, all). Both pNrf2 and cytoplasmic Nrf2 expression were associated with decreased overall survival (p < 0.05, both), and cytoplasmic Nrf2 expression was an independent predictor of decreased overall survival on multivariate analysis (hazard ratio 4.15, p < 0.001). Both pNrf2 and cytoplasmic Nrf2 expression were associated with poor survival and aggressive behavior of HCC. In addition, Keap1 expression was also associated with aggressive HCC behavior in CAIX-negative HCCs, suggesting that Keap1 expression should be interpreted in the context of hypoxia status.

Tumor necrosis as a poor prognostic predictor on postoperative survival of patients with solitary small hepatocellular carcinoma

Background

Small hepatocellular carcinoma (sHCC) is a special subtype of HCC with the maximum tumor diameter ≤ 3 cm and excellent long-term outcomes. Surgical resection or radiofrequency ablation provides the greatest chance for cure; however, many patients still undergo tumor recurrence after primary treatment. To date, there is no clinical applicable method to assess biological aggressiveness in solitary sHCC.

Methods

In the current study, we retrospectively evaluated tumor necrosis of 335 patients with solitary sHCC treated with hepatectomy between December 1998 and 2010 from Sun Yat-sen University Cancer Center.

Results

The presence of tumor necrosis was observed in 157 of 335 (46.9%) sHCC patients. Further correlation analysis showed that tumor necrosis was significantly correlated with tumor size and vascular invasion (P = 0.026, 0.003, respectively). The presence of tumor necrosis was associated closely with poorer cancer-specific overall survival (OS) and recurrence-free survival (RFS) as evidenced by univariate (P <  0.001; hazard ratio, 2.821; 95% CI, 1.643–4.842) and multivariate analysis (P = 0.005; hazard ratio, 2.208; 95% CI, 1.272–3.833). Notably, the combined model by tumor necrosis, vascular invasion and tumor size can significantly stratify the risk for RFS and OS and improve the ability to discriminate sHCC patients’ outcomes (P <  0.0001 for both).

Conclusions

Our results provide evidence that tumor necrosis has the potential to be a parameter for cancer aggressiveness in solitary sHCC. The combined prognostic model may be a useful tool to identify solitary sHCC patients with worse outcomes.

CK19-positive Hepatocellular Carcinoma is a Characteristic Subtype

The heterogeneity of hepatocellular carcinoma (HCC) commonly leads to therapeutic failure of HCC. Cytokeratin 19 (CK19) is well acknowledged as a biliary/progenitor cell marker and a marker of tumor stem cell. CK19-positive HCCs demonstrate aggressive behaviors and poor outcomes which including worse overall survival and early tumor recurrence after hepatectomy and liver transplantation. CK19-positive HCCs are resistant to chemotherapies as well as local treatment. This subset of HCC is thought to derive from liver progenitor cells and can be induced by extracellular stimulation such as hypoxia. Besides being a stemness marker, CK19 plays an important role in promoting malignant property of HCC. The regulatory network associated with CK19 expression has been summarized that extracellular stimulations which transmit into cytoplasm through signal transduction pathways (TGF-β, MAKP/JNK and MEK-ERK1/2), further induce important nuclear transcriptional factors (SALL4, AP1, SP1) to activate CK19 promoter. Novel noncoding RNAs are also involved in the regulation of CK19 expression. TGFβR1 becomes a therapeutic target for CK19-positive HCC. In conclusion, CK19 can be a potential biomarker for predicting poor prognosis after surgical and adjuvant therapies. CK19-pisitive HCCs exhibit distinctive molecular profiling, should be diagnosed and treated as a separate subtype of HCCs.

A Novel Pre-treatment Model Predicting Risk of Developing Refractoriness to Transarterial Chemoembolization in Unresectable Hepatocellular Carcinoma

Background and aim: Refractoriness to transarterial chemoembolization is common during the therapeutic process of hepatocellular carcinoma, which is an intractable issue and may compromise the prognosis. We aim to establish a pre-treatment model to identify patients with high risks of refractoriness.

Methods: From 2010 to 2016, 824 treatment-naive patients who had initially underwent at least two sessions of transarterial chemoembolization in Zhongshan Hospital, Fudan University were retrospectively enrolled. These patients were randomly allocated into a training cohort and a validation cohort. The pre-treatment scoring model was established based on the clinical and radiological variables using logistic regression and nomogram. The discrimination and calibration of the model were also evaluated.

Results: Logistic regression identified vascularization pattern, ALBI grade, serum alpha-fetoprotein level, serum γ-glutamyl transpeptidase level and major tumor size as the key parameters related to refractoriness. The p-TACE model was established using these variables (risk score range: 0-19.5). Patients were divided into six risk subgroups based on their scores (<4, ≥4, ≥7, ≥10, ≥13, ≥16). The discriminative ability, as determined by the area under receiver operating characteristic curve was 0.784 (95% confidence interval: 0.741-0.827) in the training cohort and 0.743 (95% confidence interval: 0.696-0.789) in the validation cohort. Moreover, satisfactory calibration was confirmed by Hosmer-Lemeshow test with P values of 0.767 and 0.913 in the training cohort and validation cohort.

Conclusions: This study presents a pre-treatment model to identify patients with high risks of refractoriness after transarterial chemoembolization and shed light on clinical decision making.

Noninvasive prediction of HCC with progenitor phenotype based on gadoxetic acid-enhanced MRI

OBJECTIVES

To explore the noninvasive prediction of hepatocellular carcinoma (HCC) with progenitor phenotype based on gadoxetic acid-enhanced magnetic resonance imaging (MRI).

METHODS

This retrospective study included 115 surgery-proven HCCs with preoperative gadoxetic acid-enhanced MRI from August 2015 to September 2018. Image features were reviewed. Quantitative image analysis was performed using histogram analysis. HCC with progenitor phenotype was defined as positive for either cytokeratin 19 (CK19) or epithelial cell adhesion molecule (EpCAM) expression. Statistically significant variables for identifying HCCs with progenitor phenotype were determined at multivariate analyses. ROC analyses were used to determined cutoff values and the diagnostic performance of significant variables and combinations. Prediction nomogram was constructed based on multivariate analysis.

RESULTS

At multivariate regression analyses, AFP ≥ 155.25 ng/mL (p < 0.001), skewness on T2WI ≤ 1.10 (p = 0.024), uniformity on pre-T1WI ≤ 0.91 (p = 0.024), irregular tumor margin (p = 0.006), targetoid appearance (p = 0.001), and the absence of mosaic architecture (p = 0.014) were significant predictors of HCCs expressing progenitor cell markers. Combing any three of those significant variables, it provides a diagnostic accuracy of 0.86 (95% CI 0.78-0.92) with sensitivity of 0.97 (95% CI 0.86-1.00), and specificity of 0.74 (95% CI 0.63-0.83). The C-index of the regression coefficient-based nomogram was 0.94 (95% CI 0.91-0.98).

CONCLUSIONS

Noninvasive prediction of HCCs with progenitor phenotype can be achieved with high accuracy by integrated interpretation of biochemical and radiological information, representing a handy tool for precise patient management and the prediction of prognosis.

KEY POINTS

• Qualitative image features of irregular tumor margin, targetoid appearance, and the absence of mosaic architecture are significant predictors of hepatocellular carcinoma with progenitor phenotype. • Quantitative analyses using whole-lesion histogram analysis provides additional information for the prediction of hepatocellular carcinoma with progenitor phenotype. • Noninvasive prediction of hepatocellular carcinoma with progenitor phenotype can be achieved with high accuracy by integrated interpretation of clinical information and qualitative and quantitative imaging analyses.

Gross type of hepatocellular carcinoma reflects the tumor hypoxia, fibrosis, and stemness-related marker expression

BACKGROUND

Hepatocellular carcinoma (HCC) is subclassified into five gross types, namely, vaguely nodular (VN), single nodular (SN), single nodular with extranodular growth (SNEG), confluent multinodular (CM), and infiltrative (INF) type. However, the pathological background underlying differences in biological behavior of different gross types of HCC remains unclear.

METHODS

The histopathological features, clinical outcomes of HCC gross types, and their relationships with stemness-related marker status and fibrotic/hypoxic tumor microenvironment (TME) were evaluated in 266 resected HCCs. The stemness-related markers (CD24, CD44, CD133, SALL4, YAP1, K19 and EpCAM), fibrous tumor stroma (αSMA), and hypoxia (CAIX) were evaluated with immunohistochemistry.

RESULTS

Poorer differentiation, reduced capsule formation, higher microvascular invasion, larger tumor size and larger area of necrosis were observed in order of VN-SN-SNEG-CM-INF type (p = 0.005 for all, linear-by-linear association). The expression of summed stemness-related markers and hypoxic/fibrotic TME showed an increasing trend in order of VN-SN-SNEG-CM-INF type (p < 0.005), and their expression well correlated with each other. INF type was found only in HCCs with hypoxic/fibrotic TME or high expression of stemness-related markers. CAIX expression and tumor necrosis ≥ 30% were independent prognostic markers for disease-specific survival. Early recurrence-free survival showed a significant difference based on gross types, revealing best outcome with VN type and worst outcome with INF type.

CONCLUSION

The marker expression of stemness-related and hypoxic/fibrotic TME of HCC showed an increasing trend in order of VN-SN-SNEG-CM-INF gross types, and their cross-talk may be involved in the determination of various gross-morphological features and their distinct biological behavior.

Increased Expression of the Matrix-Modifying Enzyme Lysyl Oxidase-Like 2 in Aggressive Hepatocellular Carcinoma with Poor Prognosis

Background/Aims

Lysyl oxidase-like 2 (LOXL2), a collagen-modifying enzyme, has been implicated in cancer invasiveness and metastasis.

Methods

We evaluated the expression of LOXL2 protein, in addition to carbonic anhydrase IX (CAIX), keratin 19, epithelial cell adhesion molecule, and interleukin 6, in 105 resected hepatocellular carcinomas (HCCs) by immunohistochemistry.

Results

LOXL2 positivity was found in 14.3% (15/105) of HCCs, and it was significantly associated with high serum α-fetoprotein levels, poor differentiation, fibrous stroma, portal vein invasion, and advanced TNM stage (p＜0.05 for all). Additionally, LOXL2 positivity was significantly associated with CAIX (p=0.005) and stromal interleukin 6 expression (p=0.001). Survival analysis of 99 HCC patients revealed LOXL2 positivity to be a poor prognostic factor; its prognostic impact appeared in progressed HCCs. Furthermore, LOXL2 positivity was shown to be an independent predictor of overall survival and disease-specific survival (p＜0.05 for all). Interestingly, co-expression of LOXL2 and CAIX was also an independent predictor for overall survival, disease-specific survival, disease-free survival, and extrahepatic recurrence-free survival (p＜0.05 for all).

Conclusions

LOXL2 expression represents a subgroup of HCCs with more aggressive behavior and is suggested to be a poor prognostic marker in HCC patients.

Update on hepatocellular carcinoma: Pathologists’ review

Histopathologic diversity and several distinct histologic subtypes of hepatocellular carcinoma (HCC) are well-recognized. Recent advances in molecular pathology and growing knowledge about the biology associated with distinct histologic features and immuno-profile in HCC allowed pathologists to update classifications. Improving sub-classification will allow for more clinically relevant diagnoses and may allow for stratification into biologically meaningful subgroups. Therefore, immuno-histochemical and molecular testing are not only diagnostically useful, but also are being incorporated as crucial components in predicting prognosis of the patients with HCC. Possibilities of targeted therapy are being explored in HCC, and it will be important for pathologists to provide any data that may be valuable from a theranostic perspective. Herein, we review and provide updates regarding the pathologic sub-classification of HCC. Pathologic diagnostic approach and the role of biomarkers as prognosticators are reviewed. Further, the histopathology of four particular subtypes of HCC: Steatohepatitic, clear cell, fibrolamellar and scirrhous - and their clinical relevance, and the recent consensus on combined HCC-cholangiocarcinoma is summarized. Finally, emerging novel biomarkers and new approaches to HCC stratification are reviewed.

Hepatocellular Carcinoma with Irregular Rim-Like Arterial Phase Hyperenhancement: More Aggressive Pathologic Features

BACKGROUND AND AIMS

The purpose of our study was to examine the histopathologic characteristics of hepatocellular carcinoma (HCC) with irregular rim-like arterial phase enhancement (IRE), which has been reported to be associated with more aggressive tumor behavior.

METHODS

We investigated 84 pathologically confirmed HCCs in 84 patients who underwent curative hepatic resection after gadoxetate-enhanced magnetic resonance imaging between January 2008 and February 2013. Two abdominal radiologists independently reviewed these images and classified HCCs into two categories: HCC showing IRE (IRE-HCC) and HCC showing hypoenhancement or diffuse arterial enhancement (non-IRE-HCC). Twenty-two HCCs were classified as IRE-HCCs, and 51 were classified as non-IRE-HCCs concordantly by both reviewers. The remaining 11 HCCs, on whose radiologic classifications the reviewers disagreed, were classified as HCCs with intermediate enhancement patterns. The HCC clinicopathologic characteristics and patient outcomes were then compared.

RESULTS

IRE-HCCs showed more frequent microvascular invasion (91 vs. 35%), lower microvascular density (246.5 vs. 426.5/mm²), higher proportions of sinusoid-like microvascular pattern (55 vs. 0%) and macrotrabecular pattern (45 vs. 0%), and larger areas of tumor necrosis (15 vs. 0%) and fibrous stroma (8.3 vs. 2.1%) than non-IRE-HCCs. IRE-HCCs also expressed higher levels of immunomarkers of hypoxia (carbonic anhydrase IX, 64 vs. 8%) and stemness (EpCAM, 50 vs. 20%). p values were < 0.001 for all comparisons except for EpCAM (p = 0.026). HCCs with intermediate enhancement patterns showed mixed/intermediate pathologic features from both IRE- and non-IRE-HCCs. IRE-HCC patients showed poorer 5-year disease-free survival after curative resection than non-IRE-HCC patients (p = 0.005).

CONCLUSIONS

IRE-HCCs demonstrate aggressive histopathologic features, including more hypoxic and fibrotic tumor microenvironments and increased stemness, compared to non-IRE-HCCs. IRE might therefore serve as a noninvasive imaging biomarker for aggressive HCC.

Metformin attenuates hypoxia-induced resistance to cisplatin in the HepG2 cell line

Hepatoblastoma is the most commonly occurring liver tumor in children. Preoperative chemotherapy and surgery have improved treatment outcomes; however, further improvements are required in the treatment of advanced cases. Recently, the efficacy of transarterial chemoembolization (TACE) has garnered attention. TACE increases the local concentration of drugs by transcatheterically administering antitumor agents, and induces necrosis in the tumor by embolizing the feeding artery. However, studies have revealed that tumors exhibit resistance to anticancer drugs in hypoxic environments. Metformin is a drug used to treat type 2 diabetes; however, recent reports have indicated that it may also exhibit antitumor effects in various cancer cell lines. These effects are hypothesized to be mediated by the activation of adenosine monophosphate-activated protein kinase and reduction of mammalian target of rapamycin signaling, but these effects occur at high concentrations that are not suitable for use in a clinical setting. The potential efficacy of metformin at increased physiological concentrations has not been evaluated. The present study investigated the therapeutic effect of low concentrations of metformin in combination with cisplatin on liver cancer HepG2 cells in hypoxic conditions. HepG2 cells were treated with cisplatin alone, metformin alone, or a combination of these two drugs and cultured in normoxia or hypoxia. Treatment with either 5 µM cisplatin or 1 mM metformin alone did not significantly affect cell proliferation or apoptosis in hypoxic conditions. However, when 5 µM cisplatin was combined with 1 mM metformin, a significant inhibition of cell proliferation and induction of apoptosis was observed in hypoxic HepG2 cells. In conclusion, a low concentration of metformin attenuates hypoxia-induced resistance to cisplatin in HepG2 cells. Selective delivery of an effective dose of metformin to a hepatoblastoma tumor may be achievable and clinically useful with TACE.