Therapeutic strategies for hepatocellular carcinoma: new advances and challenges

Direct-Acting Antivirals Improve Overall Survival in Interventional Oncology Patients with Hepatitis C and Hepatocellular Carcinoma

PURPOSE

To investigate the impact of direct-acting antivirals (DAAs) and 12-week sustained virologic response (SVR12) in patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) treated by interventional oncology (IO) therapies.

MATERIALS AND METHODS

Retrospective analysis of patients diagnosed from 2005 to 2016 with HCC and receiving IO therapies. A total of 478 patients met inclusion criteria. Patients were age 29-90 years (mean 63.6 ± 9.4 years) and 78.9% (n =3 77) male. Two hundred and eighty-five (57%) patients had chronic HCV, 93 (33%) received DAAs, and 63 (68%) achieved SVR12. Liver function, tumor characteristics, and IO therapy including ablation, image-guided transcatheter tumor therapies (ITTT) (eg, chemoembolization and radioembolization), and combination locoregional therapy were assessed in analysis.

RESULTS

Median overall survival (OS) of the cohort was 26.7 months (95% confidence interval [CI] 21.9-29.9). OS for ablation, combination locoregional therapy and ITTT, was 37.3 (CI 30.7-49.9), 29.3 (CI 24.2-38.0), and 19.7 months (CI 16.5-22.8), respectively (P < .0001). OS in patients with HCV was 30.7 months (CI 24.2-35.2) versus 22.2 months in non-HCV patients (CI 17.8-27.8, P = .03). Patients with HCV who received DAA had higher survival, 49.2 months (CI 36.5-not reached) versus those not receiving DAA, 18.5 months (CI 14.1-25.3, P < .0001). OS was 71.8 months (CI 42.3-not reached) for patients who achieved SVR12 after DAA versus 26.7 months in the non-SVR12 group (CI 15.9-31.1, P < .0001). Multivariable analysis revealed independent factors for OS including IO treatment type, DAA use and achieving SVR12 (P < .05).

CONCLUSIONS

DAA use and SVR12 is associated with higher OS in patients with HCV-related HCC treated by IO therapies.

Polo-like kinase 1 as a promising diagnostic biomarker and potential therapeutic target for hepatocellular carcinoma

Hepatocellular carcinoma is a major cause of cancer mortality worldwide. The outcome of hepatocellular carcinoma depends mainly on its early diagnosis. To date, the performance of traditional biomarkers is unsatisfactory. Polo-like kinase 1 is a serine/threonine kinase that plays essential roles in cell cycle progression and deoxyribonucleic acid damage. Moreover, polo-like kinase 1 knockdown decreases the survival of hepatocellular carcinoma cells; therefore, polo-like kinase 1 is an attractive target for anticancer treatments. Nobiletin, a natural polymethoxy flavonoid, exhibits a potential antiproliferative effect against a wide variety of cancers. This study targets to identify a reliable diagnostic biomarker for hepatocellular carcinoma and provide a potential therapeutic target for its treatment. Polo-like kinase 1 levels were analyzed in 44 hepatocellular carcinoma patients, 33 non-hepatocellular carcinoma liver cirrhosis patients and 15 healthy controls using the enzyme-linked immunosorbent assay method. Receiver operating characteristics curve analysis was used to establish a predictive model for polo-like kinase 1 relative to α-fetoprotein in hepatocellular carcinoma diagnosis. Furthermore, in the in vitro study, gene expressions were assessed by quantitative polymerase chain reaction in two human hepatocellular carcinoma cell lines after treatment with doxorubicin and polo-like kinase 1 inhibitor volasertib (Vola) either alone or in combination with nobiletin. Cell viability was also determined using the crystal violet assay.: Serum polo-like kinase 1 levels in hepatocellular carcinoma patients were significantly higher than liver cirrhosis and control groups (p < 0.0001). Polo-like kinase 1 showed a reasonable sensitivity, specificity, positive predictive value, and negative predictive value in hepatocellular carcinoma diagnosis. Moreover, nobiletin improved inhibition of cell growth induced by Vola and doxorubicin. Regarding reverse transcription polymerase chain reaction results, nobiletin suppressed expressions of polo-like kinase 1 and proliferating cell nuclear antigen and elevated expressions of P53, poly (ADPribose) polymerase 1, and caspase-3. Nobiletin/doxorubicin and nobiletin/Vola showed a significant increase in caspase-3 activity indicating cell apoptosis. Polo-like kinase 1 may be a potential biomarker for hepatocellular carcinoma diagnosis and follow-up during treatment with chemotherapies. In addition, nobiletin synergistically potentiates the doxorubicin and Vola-mediated anticancer effect that may be attributed partly to suppression of polo-like kinase 1 and proliferating cell nuclear antigen expression and enhancement of chemotherapy-induced apoptosis.

Significance of PD-L1 clones and C-MET expression in hepatocellular carcinoma

Programmed cell death ligand 1 (PD-L1) is an essential immune checkpoint protein implicated in immune evasion by malignant tumors. Overexpression of programmed cell death protein 1 (PD-1) and its ligand PD-L1 is associated with poor prognosis in various types of cancer. Recently, multiple advances have occurred in the area of cancer immunotherapy. Inhibiting the ligation of PD-1 by PD-L1 has been the major focus of anti-tumor immunotherapy. In diagnostic pathology, it has become crucial to detect PD-L1⁺ tumor cases using a validated immunohistochemistry (IHC) approach. Preliminary data demonstrate that C-MET promotes survival of some (e.g., renal) cancer types through regulation of PD-L1. However, C-MET expression, and its association with PD-L1, has not been well-characterized in the context of hepatocellular carcinoma (HCC), and no anti-HCC immunotherapy is currently available in Korea. Therefore, it is crucial to investigate the expression of C-MET and PD-L1, and their association with clinicopathologic factors, to facilitate the development of targeted treatments for HCC. PD-L1 expression was examined in tumor cells (TC) and immune cells (IC) of 70 patient-derived HCC specimens using IHC. Two anti-PD-L1 monoclonal antibodies (MAbs), SP263 and SP142, were utilized. Additionally, TC C-MET expression was assessed. Correlations between PD-L1 expression (as identified by both MAbs), C-MET expression and clinicopathologic factors were assessed. More PD-L1⁺ cases were identified via SP263 than via SP142 when assessing both TC and IC; in the former group, SP236 identified 14/70 positive cases, while SP142 identified only 2/70. In the latter group, SP236 identified 49/70 positive cases, while SP142 identified 30/70. Both MAbs demonstrated a higher frequency of PD-L1 expression by IC than TC. The Edmondson-Steiner grade statistically correlated with a higher frequency of SP236-detected TC PD-L1 expression. C-MET was significantly associated with advanced tumor size and was positively correlated with SP263-detected PD-L1 expression in TC. These results suggest that C-MET may serve a role in regulating PD-L1 expression in HCC. Furthermore, while SP263 generally exhibited a higher sensitivity for PD-L1 detection, concordance in PD-L1⁺ case detection between the two different MAbs was generally good. These background data may be helpful in the development of targeted anti-HCC immunotherapy focused on PD-L1 or C-MET, and in evaluating selection criteria for target populations best suited to such treatments.

Gain of UBE2D1 facilitates hepatocellular carcinoma progression and is associated with DNA damage caused by continuous IL-6

Background

Hepatocellular carcinoma (HCC) is the most common type of liver cancer with increasing incidence and poor prognosis. Ubiquitination regulators are reported to play crucial roles in HCC carcinogenesis. UBE2D1, one of family member of E2 ubiquitin conjugating enzyme, mediates the ubiquitination and degradation of tumor suppressor protein p53. However, the expression and functional roles of UBE2D1 in HCC was unknown.

Methods

Immunohistochemistry (IHC), western blotting, and real-time PCR were used to detect the protein, transcription and genomic levels of UBE2D1 in HCC tissues with paired nontumor tissues, precancerous lesions and hepatitis liver tissues. Four HCC cell lines and two immortalized hepatic cell lines were used to evaluate the functional roles and underlying mechanisms of UBE2D1 in HCC initiation and progression in vitro and in vivo. The contributors to UBE2D1 genomic amplification were first evaluated by performing a correlation analysis between UBE2D1 genomic levels with clinical data of HCC patients, and then evaluated in HCC and hepatic cell lines.

Results

Expression of UBE2D1 was significantly increased in HCC tissues and precancerous lesions and was associated with reduced survival of HCC patients. Upregulation of UBE2D1 promoted HCC growth in vitro and in vivo by decreasing the p53 in ubiquitination-dependent pathway. High expression of UBE2D1 was attributed to the recurrent genomic copy number gain, which was associated with high serum IL-6 level of HCC patients. Further experiments showed that continuous IL-6 activated the DNA damage response and genomic instability by repressing DNA damage checkpoint protein RAD51B. Moreover, continuous IL-6 could significantly facilitate the HCC growth especially with the genomic gain of UBE2D1.

Conclusions

Our findings showed that UBE2D1 played a crucial role in HCC progression, and suggested a novel pattern of continuous IL-6 to promote cancers by inducing the genomic alterations of specific oncogenes.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0951-8) contains supplementary material, which is available to authorized users.

Upregulation of UBE2Q1 via gene copy number gain in hepatocellular carcinoma promotes cancer progression through β-catenin-EGFR-PI3K-Akt-mTOR signaling pathway

Hepatocellular carcinoma (HCC) is the most common type of liver cancer and represents a highly malignant tumor with a poor prognosis. Therapeutic modalities for HCC are limited and generally ineffective. UBE2Q1 is a putative E2 ubiquitin conjugating enzyme, and has been shown to be overexpressed in various types of cancers including HCC. How UBE2Q1 contributes to hepatocarcinogenesis remains unknown. Here, we show that UBE2Q1 is up-regulated in HCC cell lines and in a subset of human HCC tissues. Up-regulation of UBE2Q1 in primary HCC tumors was significantly correlated with shorter overall survival and disease-free survival. Mechanistically, we showed that the frequent up-regulation of UBE2Q1 in HCCs was attributed to the recurrent UBE2Q1 gene copy gain at chromosome 1q21. Functionally, we showed that knockdown of UBE2Q1 reduced HCC cell proliferation, promoted apoptosis via induction of GADD45α, and suppressed orthotopic tumorigenicity both in vitro and in vivo. Inactivation of UBE2Q1 also impeded HCC cell migration and invasion in vitro through regulating EMT process, and suppressed HCC metastasis in vivo. Interestingly, our data revealed a role of UBE2Q1 in the regulation of β-catenin-EGFR-PI3K-Akt-mTOR signaling pathway. Our findings indicate that UBE2Q1 is a candidate oncogene involved in HCC development and progression and therefore a potential therapeutic target in applicable HCC patients.

Pretransplant Intra-arterial Liver-Directed Therapy Does Not Increase the Risk of Hepatic Arterial Complications in Liver Transplantation: A Single-Center 10-Year Experience

PURPOSE

To investigate the association between pretransplant intra-arterial liver-directed therapy (IAT) for hepatocellular carcinoma (HCC) and hepatic arterial complications (HAC) in orthotopic liver transplantation (OLT) [namely hepatic artery thrombosis (HAT) and/or the need for hepatic arterial conduit].

METHODS

A total of 175 HCC patients (mean age: 60 years) underwent IAT with either transarterial chemoembolization or yttrium-90 (90Y) transarterial radioembolization prior to OLT between 2003 and 2013. A matched control cohort of 159 HCC patients who underwent OLT without prior IAT was selected. Incidence of HAC in both cohorts was investigated. The categorical differences between both cohorts were calculated by chi-square test.

RESULTS

Among the 175 patients (chemoembolization, n = 82; radioembolization, n = 93), 8 (5%) required conduits due to HA disease (chemoembolization, n = 6; radioembolization, n = 2), 3 (2%) developed HAT (chemoembolization, n = 2; radioembolization, n = 1). Eleven of 175 patients (6.7%) had HAC. Of the 159 control patients, 6 (4%) needed conduits for HA disease and 3 (2%) developed HAT. Nine of 159 patients (5.7%) had HAC. Chi-square analysis between the IAT cohort and the control group yielded a p value of 0.810. When comparing chemoembolization to radioembolization, p = 0.076 (not significant at p < 0.05).

CONCLUSION

Although aggressive pretransplant radioembolization and chemoembolization are both utilized in most liver transplant centers, neither appears to increase the risk of peri-transplant hepatic arterial complications in HCC patients.

Evaluation of 99mTc-3PRGD2 integrin receptor imaging in hepatocellular carcinoma tumour-bearing mice: comparison with 18F-FDG metabolic imaging

Objective

Our study was designed to explore the utility of ^99mTc-HYNIC-PEG₄-E[PEG₄-c(RGDfK)]₂ (^99mTc-3PRGD₂) for the detection of hepatocellular carcinoma (HCC) and specifically to compare the diagnostic performance of ^99mTc-3PRGD₂ integrin receptor imaging and 2-18-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) metabolic imaging in a nude mouse model.

Methods

^99mTc-3PRGD₂ was synthesized using a HYNIC-3PRGD₂ lyophilized kit with ^99mTcO₄ labelling. The nude mouse animal model was established by subcutaneously injecting 5 × 10⁷/ml HepG2 cells into the shoulder flank of each mouse. Biodistribution studies were performed at 0.5, 1, 2 and 4 h after intravenous administration of 0.37 MBq of ^99mTc-3PRGD₂. Immunohistochemistry was performed to evaluate the expression level of integrin αvβ3 in the HCC tissues. Dynamic imaging was performed using list-mode after the administration of 55.5 MBq of ^99mTc-3PRGD₂, to reconstruct the multiphase images and acquire the best initial scan time. At 8, 12, 16, 20 and 24 days after inoculation with HepG2 cells, 55.5 MBq of ^99mTc-3PRGD₂ and 37 MBq of ¹⁸F-FDG were injected successively into the nude mouse model, subsequently, simultaneous SPECT/PET imaging was performed to calculate the tumour volume and tumour uptake of ^99mTc-3PRGD₂ and ¹⁸F-FDG.

Results

The biodistribution study first validated that the tumour uptake of ^99mTc-3PRGD₂ at the different time points was higher than that of all the other organs tested in the experiment, except for the kidney. Integrin αvβ3 expressed highly in early stage HCC and declined for further necrosis of the tumour tissue. Subcutaneous tumours were visualized clearly with excellent contrast under ^99mTc-3PRGD₂ SPECT/CT imaging, and the multiphase imaging comparison showed the tumours were prominent at 0.5 h, suggesting that the best initial scan time is 0.5 h post-injection. The comparison of the imaging results of the two methods showed that ^99mTc-3PRGD₂ integrin receptor imaging was more sensitive than ¹⁸F-FDG metabolic imaging for the detection of early stage HCC, meanwhile the tumour uptake of ^99mTc-3PRGD₂ was consistently higher than that of ¹⁸F-FDG. However, as tumour necrosis further increased in HCC tissues, the uptake of ¹⁸F-FDG was higher than that of ^99mTc-3PRGD₂.

Conclusion

Our study demonstrated that ^99mTc-3PRGD₂ is a valuable tumour molecular probe for the detection of early stage HCC compared with ¹⁸F-FDG, meriting further investigation of ^99mTc-3PRGD₂ as a novel SPECT tracer for tumour imaging.

Treating hepatocellular carcinoma with 90Y-bearing microspheres: a review

Hepatocellular carcinoma (HCC) is a disease usually diagnosed in its advanced-stage, and is frequently not amenable to curative surgical treatment. Also, HCC is resistant to chemotherapy and less vulnerable to radiation therapy compared to normal hepatic parenchyma. Both of these facts render the efficacy of adjuvant and palliative treatments problematic. Selective internal radiation therapy (SIRT) with ⁹⁰Y-bearing microspheres is characterized by preferentially delivering substantially high doses of radiation to a liver tumor dose simultaneously limiting the damage to its non-tumorous cells, providing an opportunity for effective local tumor control and even tumor regression therapy. The current article reviews the specific characters, dosimetry, possible applications, and special considerations toward the pre-existing radiation therapy of ⁹⁰Y microsphere SIRT in treating HCC.

68Ga and 188Re Starch-Based Microparticles as Theranostic Tool for the Hepatocellular Carcinoma: Radiolabeling and Preliminary In Vivo Rat Studies

PURPOSE

This work aims to develop, validate and optimize the radiolabeling of Starch-Based Microparticles (SBMP) by 188Re and 68Ga in the form of ready-to-use radiolabeling kits, the ultimate goal being to obtain a unique theranostic vector for the treatment of Hepatocellular Carcinoma.

METHODS

Optimal labeling conditions and composition of freeze-dried kits were defined by monitoring the radiochemical purity while varying several parameters. In vitro stability studies were carried out, as well as an in vivo biodistribution as a preliminary approach with the intra-arterial injection of 68Ga radiolabeled SBMP into the hepatic artery of DENA-induced rats followed by PET/CT imaging.

RESULTS

Kits were optimized for 188Re and 68Ga with high and stable radiochemical purity (>95% and >98% respectively). The in vivo preliminary study was successful with more than 95% of activity found in the liver and mostly in the tumorous part.

CONCLUSION

SBMP are a promising theranostic agent for the Selective Internal Radiation Therapy of Hepatocellular carcinoma.

Overexpression of PD-L1 and PD-L2 Is Associated with Poor Prognosis in Patients with Hepatocellular Carcinoma

Purpose

Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies. Recently, the overexpression of programmed cell death 1 (PD-1) and PD-1 ligand 1 (PD-L1) has been shown to correlate with poor prognosis in many cancers. However, the expression of PD-L1 or PD-1 ligand 2 (PD-L2) and clinical outcomes have not been fully investigated in HCC.

Materials and Methods

Formalin-fixed paraffin-embedded samples were obtained from 85 patients with HCC who underwent surgery. The expression of PD-Ls (PD-L1, PD-L2) was evaluated by immunohistochemical analysis.

Results

The proportion of high expression groups of PD-L1 and PD-L2 was 27.1% and 23.5%, respectively. Univariate analysis revealed that tumor size (p < 0.001), histological differentiation (p=0.010), PD-L1 expression (p < 0.001), and PD-L2 expression (p=0.039) were significant prognostic factors of overall survival in patients with HCC. Multivariate analysis revealed that overall tumor size (hazard ratio [HR], 4.131; 95% confidence interval [CI], 2.233 to 7.643; p < 0.001 and HR, 3.455; 95% CI, 1.967 to 6.067; p < 0.001) and PD-L1 expression (HR, 5.172; 95% CI, 2.661 to 10.054; p < 0.001 and HR, 3.730; 95% CI, 1.453 to 9.574; p=0.006) were independent prognostic values for overall and disease-free survival. Patients with high expression of PD-Ls had a significantly poorer survival than those with low expression (p < 0.001, p=0.034).

Conclusion

The overexpression of PD-Ls in HCC patients is correlated with survival and tumor recurrence. Further evaluation of PD-1 and PD-Ls as therapeutic targets and predictive biomarkers for HCC is warranted.

Hepatic imaging following intra-arterial embolotherapy

PURPOSE

To discuss guidelines and salient imaging findings of solid tumors treated with common intra-arterial procedures used in interventional oncology.

METHODS

A meticulous literature search of PubMed-indexed articles was conducted. Key words included "imaging + embolization," "imaging + TACE," "imaging + radioembolization," "imaging + Y90," "mRECIST," and "EASL." Representative post-treatment cross-sectional images were obtained from past cases in this institution.

RESULTS

Intra-arterial therapy (IAT) in interventional oncology includes bland embolization, chemoembolization, and radioembolization. Solid tumors of the liver are the primary focus of these procedures. Cross-sectional CT and/or MR are the main modalities used to image tumors after treatment. Traditional size-based response criteria (WHO and RECIST) alone are of limited utility in determining response to IAT; tumoral necrosis and enhancement must be considered. Specifically for HCC, the EASL and mRECIST guidelines are becoming widely adopted response criteria to assess these factors. DWI, FDG-PET, and CEUS are modalities that play an adjunctive but controversial role.

CONCLUSIONS

Radiologists must be aware that the different forms of intra-arterial therapy yield characteristic findings on cross-sectional imaging. Knowledge of these findings is integral to accurate assessment of tumor response and progression.

Expression profile and prognostic value of glypican-3 in post-operative South Korean hepatocellular carcinoma patients

Hepatocellular carcinoma (HCC) patients commonly experience poor overall survival (OS) and disease-free survival (DFS) after curative surgical resection. Glypican-3 (GPC3) has been suggested as a prognostic biomarker for post-operative survival. However, few to none of these studies have included South Korean patients. This study aimed to determine GPC3 expression rate, clinical correlation, and post-operative prognostic value in South Korean HCC patients who underwent curative surgical resection. Surgically resected tissues from 185 HCC patients were collected and assembled into tissue microarrays (TMAs), which were stained for GPC3 by immunohistochemistry. GPC3 expression rates were correlated with clinicopathological information, and survival analyses were performed to assess the prognostic value of GPC3. GPC3 expression was present in 153 patients (82.7%). GPC3-positive patients were younger with higher frequencies of microvascular invasion and higher AFP levels than GPC3-negative patients. There was no significant difference in survival between GPC3-negative and GPC3-positive patients. Based on multivariate analysis, GPC3 expression was not a prognostic marker for post-operative survival. In South Korean HCC patients, GPC3 expression was more frequent in HCCs with aggressive features, but it was not an independent prognostic biomarker.