Prognostic factors and recurrence of small hepatocellular carcinoma after hepatic resection or microwave ablation: a retrospective study

Laparoscopic-assisted microwave ablation in treatment of small hepatocellular carcinoma: safety and efficacy in comparison with laparoscopic hepatectomy

Laparoscopic-assisted microwave ablation (LAMWA), as one of the locoregional therapies, has been employed to treat hepatocellular carcinoma (HCC). This study aims to compare the efficacy and safety of LAMWA and laparoscopic hepatectomy in the treatment of small HCC.This study included 140 patients who met the inclusion criteria. Among them, 68 patients received LAMWA and 72 patients underwent laparoscopic hepatectomy. The perioperative condition, liver function recovery, the alpha fetoprotein (AFP) level, morbidities, hospitalization time, overall survival (OS), disease-free survival (DFS) and recurrence rate between the two groups were compared. The rate of complete elimination of tumor tissue was 100% and the AFP level was returned to normal within 3 months after surgery in both groups (P > 0.05). The mean alanine transaminase (ALT) and aspartate transaminase (AST) peak in the LAMWA group was lower than that in the laparoscopic hepatectomy group (259.51 ± 188.75 VS 388.9 ± 173.65, P = 0.000) and (267.34 ± 190.65 VS 393.1 ± 185.67, P = 0.000), respectively. The mean operation time in the LAMWA group was shorter than that in the laparoscopic hepatectomy group (89 ± 31 min VS 259 ± 48 min, P = 0.000). The blood loss in the LAMWA group was less than that in the laparoscopic hepatectomy group (58.4 ± 64.0 ml VS 213.0 ± 108.2 ml, P = 0.000). Compared with the laparoscopic hepatectomy group, patients in the LAMWA group had lower mean hospital stay (4.8 ± 1.2d VS 11.5 ± 2.9d, P = 0.000). The morbidities of the LAMWA group and the hepatectomy group were 14.7%(10/68) and 34.7%(25/72), respectively (P = 0.006). The one-, three-, and five-year OS rates were 88.2%, 69.9%, 45.6% for the LAMWA group and 86.1%, 72.9%, 51.4% for the laparoscopic hepatectomy group (P = 0.693). The corresponding DFS rates for the two groups were 76.3%, 48.1%, 27.9% and 73.2%, 56.7%, 32.0% (P = 0.958). Laparoscopic-assisted microwave ablation is a safe and effective therapeutic option for selected small HCC.

Advanced hepatocellular carcinoma with MET-amplified contained excellent response to crizotinib: a case report

Introduction

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide. Several novel therapeutic strategies have been developed to prolong the survival of patients with advanced HCC. However, therapeutic decision-making biomarkers owing to the extensive heterogeneity of HCC. Next-generation sequencing (NGS) is generally used in treatment decisions to help patients benefit from genome-directed targeting.

Case presentation

A 56 year-old male with type-B hepatitis for more than 20 years was admitted to our department and underwent laparoscopic left lateral hepatic lobectomy for hepatocellular carcinoma. Unfortunately, the tumor recurred 1 year later. Despite multiple treatments, the tumor continued to progress and invaded the patient's 5th thoracic vertebras, leading to hypoesthesia and hypokinesia below the nipple line plane 2 years later. NGS revealed MET amplification, and crizotinib, an inhibitor of MET, was recommended. After administration for a month, tumor marker levels decreased, and the tumor shrunk. The patient has remained in remission since that time.

Conclusions

We report that a patient with high MET amplification benefited from its inhibitor, which was recommended by NGS. This indicates the potential clinical decision support value of NGS and the satisfactory effect of MET inhibitors.

An epigenetic modulator with promising therapeutic impacts against gastrointestinal cancers: A mechanistic review on microRNA-195

Due to their high prevalence, gastrointestinal cancers are one of the key causes of cancer-related death globally. The development of drug-resistant cancer cell populations is a major factor in the high mortality rate, and it affects about half of all cancer patients. Because of advances in our understanding of cancer molecular biology, non-coding RNAs (ncRNAs) have emerged as critical factors in the initiation and development of gastrointestinal cancers. Gene expression can be controlled in several ways by ncRNAs, including through epigenetic changes, interactions between microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) and proteins, and the function of lncRNAs as miRNA precursors or pseudogenes. As lncRNAs may be detected in the blood, circulating ncRNAs have emerged as a promising new class of non-invasive cancer biomarkers for use in the detection, staging, and prognosis of gastrointestinal cancers, as well as in the prediction of therapy efficacy. In this review, we assessed the role lncRNAs play in the progression, and maintenance of colorectal cancer, and how they might be used as therapeutic targets in the future.

Clinical Results, Risk Factors, and Future Directions of Ultrasound-Guided Percutaneous Microwave Ablation for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, with a relatively poor prognosis, especially for advanced HCC. With the availability of a variety of treatment options, the treatment strategies for HCC have become more and more diversified. Microwave ablation (MWA) has gradually been considered as a viable alternative to surgical resection (SR) owing to its comparable long-term survival, reduced complications, and greater preservation of hepatic parenchyma. However, clinical outcomes, tumor progression, and recurrence of HCC after MWA remain major concerns. Here, after reviewing the current therapeutic options for HCC, we focus on MWA, describing the advantages and challenges of MWA and the clinical results after treatment. We then focused on prognostic factors that influence post-ablation clinical outcomes and briefly presented the strategy of MWA for future clinical treatment.

Percutaneous ultrasound-guided microwave ablation for treatment of hepatocellular carcinomas in dogs: four cases (2019-2020)

OBJECTIVES

To describe ultrasound-guided microwave ablation as a minimally invasive treatment option for primary or metastatic hepatocellular carcinomas.

METHODS

Four client-owned dogs underwent percutaneous ultrasound-guided microwave ablation of three primary and one metastatic hepatocellular carcinoma, diagnosed on cytology/histopathology. In each case, multiple ultrasound-guided thermal lesions were created in a 10 to 40 minutes ablation at 30 to 35 W. Real-time monitoring was performed using 10 MHz diagnostic ultrasound transducers. The procedures were performed without complication and CT scans or abdominal ultrasounds were repeated immediately after. Patients were discharged on oral analgesia on the same day or 24 hours later.

RESULTS

Hepatocellular carcinomas were successfully ablated, which in some cases resulted in an improvement in clinical signs and laboratory values. The patients were followed up for a time ranging between 39 and 649 days and no evidence of disease progression was found. Three out of four patients are still alive at the time of writing.

CLINICAL SIGNIFICANCE

In these four patients, minimally invasive ultrasound-guided microwave ablation was feasible and resulted in no immediate complications. Regular imaging follow-up is recommended after the procedure and further studies on microwave ablation are warranted to establish its effectiveness in dogs with hepatocellular carcinomas.

HGF-mediated elevation of ETV1 facilitates hepatocellular carcinoma metastasis through upregulating PTK2 and c-MET

Background

Metastasis is a major determinant of death in patients with hepatocellular carcinoma (HCC). Dissecting key molecular mediators that promote this malignant feature may help yield novel therapeutic insights. Here, we investigated the role of E-twenty-six transformation-specific variant 1 (ETV1), a member of the E-twenty-six transformation-specific (ETS) family, in HCC metastasis. 

Methods

The clinical significance of ETV1 and its target genes in two independent cohorts of HCC patients who underwent curative resection were assessed by Kaplan–Meier analysis and Multivariate Cox proportional hazards model. Luciferase reporter assay and chromatin immunoprecipitation assay were used to detect the transcriptional regulation of target gene promoters by ETV1. The effect of ETV1 on invasiveness and metastasis of HCC were detected by transwell assays and the orthotopically metastatic model.

Results

ETV1 expression was frequently elevated in human HCC specimens. Increased ETV1 expression was associated with the malignant biological characteristics and poor prognosis of HCC patients. ETV1 facilitated invasion and metastasis of HCC cells in vitro and in vivo. Mechanistically, ETV1 promoted HCC metastasis via upregulating metastasis-related genes, including protein tyrosine kinase 2 (PTK2) and MET. Down-regulated the expression of PTK2 or tyrosine protein kinase Met (c-MET) decreased ETV1-mediated HCC metastasis. Hepatocyte growth factor (HGF) upregulated ETV1 expression through activating c-MET-ERK1/2-ELK1 pathway. Notably, in two independent cohorts, patients with positive coexpression of ETV1/PTK2 or ETV1/c-MET had worse prognosis. Furthermore, the combination of PTK2 inhibitor defactinib and c-MET inhibitor capmatinib significantly suppressed HCC metastasis induced by ETV1.

Conclusion

This study uncovers functional and prognostic roles for ETV1 in HCC and exposes a positive feedback loop of HGF-ERK1/2-ETV1-c-MET. Targeting this pathway may provide a potential therapeutic intervention for ETV1-overexpressing HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02475-2.

Effects of microwave ablation on serum Golgi protein 73 in patients with primary liver cancer

BACKGROUND

Microwave ablation (MWA) is an effective treatment option for patients with primary liver cancer. However, it has been reported that the MWA procedure induces a hepatic inflammatory response and injury, which may negatively affect the efficacy of MWA. As such, the discovery of reliable markers to monitor the patient’s response to MWA is needed. Golgi protein 73 (GP73) has been shown to be associated with chronic liver disease. To date, the potential value of serum GP73 in the dynamic monitoring during MWA of liver cancer remains unclear.

AIM

To examine the effects of MWA on the serum levels of GP73 in patients with primary liver cancer.

METHODS

A total of 150 primary liver cancer patients with a single small lesion (≤ 3 cm in diameter) were retrospectively enrolled spanning the period between January 2016 and October 2018. All of the patients received MWA for the treatment of primary liver cancer. Serum GP73, alpha-fetoprotein (AFP), and widely used liver biochemical indicators [serum albumin, total bilirubin (TBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST)] were compared before MWA and at different time points, including 1, 2, and 4 wk following the ablation procedure.

RESULTS

Complete tumor ablation was achieved in 95.33% of the patients at 1 mo after MWA. The 1-, 2-, and 3-year disease-free survival rates were 74.67%, 59.33%, and 54.00%, respectively. The serum AFP levels were significantly decreased at 1, 2, and 4 wk after MWA; they returned to the normal range at 12 wk after MWA; and they remained stable thereafter during follow-up in those cases without recurrence. In contrast, the serum GP73 levels were significantly increased at 1 and 2 wk after MWA. The serum GP73 levels reached the peak at 2 wk after MWA, started to decline after hepatoprotective treatment with glycyrrhizin and reduced glutathione, and returned to the pretreatment levels at 12 and 24 wk after MWA. Notably, the changes of serum GP73 in response to MWA were similar to those of TBIL, ALT, and AST.

CONCLUSION

Serum GP73 is markedly increased in response to MWA of liver cancer. Thus, serum GP73 holds potential as a marker to monitor MWA-induced inflammatory liver injury in need of amelioration.

Recurrence Outcome in Hepatocellular Carcinoma within Milan Criteria Undergoing Microwave Ablation with or without Transarterial Chemoembolization

Background and Objectives: The recurrence outcome in patients who underwent microwave ablation (MWA) with or without transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) within Milan criteria remains unclear. The aim of this retrospective study was to identify the predictive factors of recurrence in these patients. Materials and Methods: From May 2018 to April 2021, 66 patients with HCC within Milan criteria were enrolled. Local tumor progression (LTP) and recurrence-free survival (RFS) were evaluated. Univariate and multivariate analyses were used to evaluate the risk factors of recurrence. The propensity score analysis was conducted to reduce potential confounding bias. Results: During the median follow-up of 25.07 months (95% confidence interval [CI], 21.85, 28.28), the median time to LTP and RFS were 20.10 (95%CI, 14.67, 25.53) and 13.03 (95%CI, 6.36, 19.70) months. No group difference (MWA vs. MWA + TACE) was found in 1-year cumulative LTP (p = 0.575) and RFS (p = 0.515), but meaningful significant differences were found in two-year recurrence (LTP, p = 0.007 and RFS, p = 0.037). Univariate and multivariate analyses revealed that treatment received before ablation was an independent risk factor of LTP (hazard ratio [HR] 4.37, 95%CI, 1.44, 13.32) and RFS (HR 3.41, 95%CI, 1.49, 7.81). Conclusions: The LTP and RFS in the MWA group were similar to that in the MWA combined with TACE. For HCC within Milan criteria, both groups preferentially selected MWA. More endeavor and rigorous surveillance should be taken to relapse prevention, in patients who have received previous treatment.

ARID1A expression in hepatocellular carcinoma and relation to tumor recurrence after microwave ablation

Aim of the study

AT-rich interactive domain 1A (ARID1A) is a subunit of the switch/sucrose non-fermentable chromatin remodeling complex, which is commonly mutated in human cancers. The clinical and pathological significance of ARID1A alteration in hepatocellular carcinoma (HCC) has not yet been clarified. The present study aimed to evaluate the clinical significance of the ARID1A gene signature in HCC and its relation to the likelihood of tumor recurrence after microwave ablation (MWA).

Material and methods

This study included 50 patients with cirrhotic HCC of Barcelona Clinic Liver Cancer stages 0/A eligible for MWA. Tumor and peri-tumor biopsies were obtained just prior to MWA and assessed for tumor pathological grade and ARID1A expression by immunohistochemistry. Patients were followed for one year after complete tumor ablation to detect any recurrence.

Results

Tumor size (^MCp = 0.010) and α-fetoprotein level (p = 0.013) can effectively predict the response to MWA. Nuclear expression of ARID1A was significantly lower in HCC compared to the corresponding peri-tumor cirrhotic liver tissues (p = 0.002), but no significant difference in ARID1A cytoplasmic expression was found. Nuclear ARID1A expression level in HCC showed a significantly negative relation to tumor size (^MCp = 0.006), pathological grade (^MCp = 0.046) and post-MWA tumor recurrence (^FEp = 0.041).

Conclusions

ARID1A loss may enhance HCC aggressiveness and post-MWA tumor recurrence. ARID1A could be a potential target to select HCC patients for future therapies.

The hepatocyte growth factor/mesenchymal epithelial transition factor axis in high-risk pediatric solid tumors and the anti-tumor activity of targeted therapeutic agents

Clinical trials completed in the last two decades have contributed significantly to the improved overall survival of children with cancer. In spite of these advancements, disease relapse still remains a significant cause of death in this patient population. Often, increasing the intensity of current protocols is not feasible because of cumulative toxicity and development of drug resistance. Therefore, the identification and clinical validation of novel targets in high-risk and refractory childhood malignancies are essential to develop effective new generation treatment protocols. A number of recent studies have shown that the hepatocyte growth factor (HGF) and its receptor Mesenchymal epithelial transition factor (c-MET) influence the growth, survival, angiogenesis, and metastasis of cancer cells. Therefore, the c-MET receptor tyrosine kinase and HGF have been identified as potential targets for cancer therapeutics and recent years have seen a race to synthesize molecules to block their expression and function. In this review we aim to summarize the literature that explores the potential and biological rationale for targeting the HGF/c-MET pathway in common and high-risk pediatric solid tumors. We also discuss selected recent and ongoing clinical trials with these agents in relapsed pediatric tumors that may provide applicable future treatments for these patients.

Fis1 phosphorylation by Met promotes mitochondrial fission and hepatocellular carcinoma metastasis

Met tyrosine kinase, a receptor for a hepatocyte growth factor (HGF), plays a critical role in tumor growth, metastasis, and drug resistance. Mitochondria are highly dynamic and undergo fission and fusion to maintain a functional mitochondrial network. Dysregulated mitochondrial dynamics are responsible for the progression and metastasis of many cancers. Here, using structured illumination microscopy (SIM) and high spatial and temporal resolution live cell imaging, we identified mitochondrial trafficking of receptor tyrosine kinase Met. The contacts between activated Met kinase and mitochondria formed dramatically, and an intact HGF/Met axis was necessary for dysregulated mitochondrial fission and cancer cell movements. Mechanically, we found that Met directly phosphorylated outer mitochondrial membrane protein Fis1 at Tyr38 (Fis1 pY38). Fis1 pY38 promoted mitochondrial fission by recruiting the mitochondrial fission GTPase dynamin-related protein-1 (Drp1) to mitochondria. Fragmented mitochondria fueled actin filament remodeling and lamellipodia or invadopodia formation to facilitate cell metastasis in hepatocellular carcinoma (HCC) cells both in vitro and in vivo. These findings reveal a novel and noncanonical pathway of Met receptor tyrosine kinase in the regulation of mitochondrial activities, which may provide a therapeutic target for metastatic HCC.

Magnetite Fe3O4 Nanoparticles Enhance Mild Microwave Ablation of Tumor by Activating the IRE1-ASK1-JNK Pathway and Inducing Endoplasmic Reticulum Stress

Purpose

With the development of nanomedicine, microwave ablation enhanced by multifunctional nanoplatforms has been widely studied for synergistic cancer therapy. Though scientists have got a lot of significant achievements in this field, the detailed molecular mechanisms and potential targets of microwave ablation enhanced by multifunctional nanoplatforms still need further exploration. In this study, we found that a kind of magnetite Fe₃O₄ nanoparticles (Fe₃O₄ NPs) could induce severe endoplasmic reticulum stress and activate cancer apoptosis under the irradiation of mild microwave.

Methods

In this study, plenty of studies including cell immunofluorescence, mitochondrial membrane potential, electron microscopy, atomic force microscopy and microwave ablation in vivo were conducted to explore the molecular mechanisms and potential targets of microwave ablation enhanced by the Fe₃O₄ NPs.

Results

The IRE1-ASK1-JNK pathway was strongly activated in A375 cells treated with both Fe₃O₄ NPs and mild microwave. The endoplasmic reticulum of the A375 cells was significantly dilated and exhibited ballooning degeneration. By investigating the mitochondrial membrane potential (ΔΨm), we found that the mitochondria of cancer cells had been significantly damaged under microwave treatment coupled with Fe₃O₄ NPs. In addition, melanoma of B16F10-bearing mice had also been effectively inhibited after being treated with Fe₃O₄ NPs and microwave.

Conclusion

In this study, we found that a kind of magnetite Fe₃O₄ nanoparticles could induce severe ER stress and activate cancer apoptosis under mild microwave irradiation. Apparent apoptosis had been observed in the A375 cells under a scanning electron microscope and transmission electron microscope. Moreover, melanoma had also been inhibited effectively in vivo. As a result, the endoplasmic reticulum stress is a promising target with clinical potential in nanomedicine and cancer therapy.

Association between the HGF/c‑MET signaling pathway and tumorigenesis, progression and prognosis of hepatocellular carcinoma (Review)

Hepatocellular carcinoma (HCC) is one of the most aggressive and lethal malignancies with a rising incidence, and is characterized by rapid progression, frequent metastasis, late diagnosis, high postoperative recurrence and poor prognosis. Therefore, novel treatment strategies for HCC, particularly advanced HCC, are urgently required. The hepatocyte growth factor (HGF)/c‑mesenchymal‑epithelial transition receptor (c‑MET) axis is a key signaling pathway in HCC and is strongly associated with its highly malignant features. Available treatments based on HGF/c‑MET inhibition may prolong the lifespan of patients with HCC; however, they do not achieve the desired therapeutic effects. The aim of the present article was to review the basic knowledge regarding the role of the HGF/c‑MET signaling pathway in HCC, and examine the association between the HGF/c‑MET signaling pathway and the tumorigenesis, progression and prognosis of HCC.

A randomized, double-blind, placebo-controlled, phase 3 study of tivantinib in Japanese patients with MET-high hepatocellular carcinoma

A previous randomized phase 2 study of hepatocellular carcinoma revealed that the c‐Met inhibitor tivantinib as second‐line treatment significantly prolonged progression‐free survival in a subpopulation whose tumor samples highly expressed c‐Met (MET‐high). Accordingly, this phase 3 study was conducted to evaluate the efficacy of tivantinib as a second‐line treatment for Japanese patients with MET‐high hepatocellular carcinoma. This randomized, double‐blind, placebo‐controlled study was conducted at 60 centers in Japan. Hepatocellular carcinoma patients with one prior sorafenib treatment and those with MET‐high tumor samples were eligible for inclusion. Registered patients were randomly assigned to either the tivantinib or placebo group at a 2:1 ratio and were treated with twice‐a‐day oral tivantinib (120 mg bid) or placebo until the discontinuation criteria were met. The primary endpoint was progression‐free survival while the secondary endpoints included overall survival and safety. Between January 2014 and June 2016, 386 patients provided consent, and 195 patients were randomized to the tivantinib (n = 134) or placebo (n = 61) group. Median progression‐free survival was 2.8 (95% confidence interval: 2.7‐2.9) and 2.3 (1.5‐2.8) mo in the tivantinib and placebo groups, respectively (hazard ratio = 0.74, 95% confidence interval: 0.52‐1.04, P = .082). Median overall survival was 10.3 (95% confidence interval: 8.1‐11.6) and 8.5 (6.2‐11.4) mo in the tivantinib and placebo group, respectively (hazard ratio = 0.82, 95% confidence interval: 0.58‐1.15). The most common tivantinib‐related grade ≥3 adverse events were neutropenia (31.6%), leukocytopenia (24.8%), and anemia (12.0%). This study did not confirm the significant efficacy of tivantinib as a second‐line treatment for Japanese patients with MET‐high hepatocellular carcinoma. (NCT02029157).

Predictors for hepatocellular carcinoma recurrence after microwave ablation

Aim of the study

Microwave ablation (MWA) for treatment of hepatocellular carcinoma (HCC) is a new promising modality. The prognosis after treatment is mainly linked to the recurrence. We aimed to investigate the predictive value of α-fetoprotein (AFP) score and Aurora B kinase (AURKB) in HCC recurrence after MWA.

Material and methods

A cross-sectional study where 25 early-stage HCC patients (Barcelona Clinic Liver Cancer 0/A-B) were treated with MWA. Tumor biopsies were obtained just prior to MWA and assessed for WHO pathological grade and AURKB expression by immunohistochemistry. AFP score was calculated and a cut-off value of 2 classifies patients into high and low risk of recurrence. After achieving complete ablation, patients were followed every 3 months for 1 year by triphasic CT to detect recurrence.

Results

Child-Pugh classification has no significant impact on prognosis of HCC after MWA (χ² = 1.924, p = 0.165). Serum AFP level and AFP score can effectively predict the response to MWA among HCC patients (χ² = 6.451, ^MCp = 0.031) (χ² = 9.0, p = 0.003), respectively. AFP score was strongly associated with the pathological grade of the tumor (r = 0.467, p = 0.019). AURKB was over-expressed in tumoral more than non-tumoral specimens (p < 0.001). It was correlated with the size of the tumor, the number of tumor nodules and the pathological grade of the tumor (p < 0.05) but has no role in predicting recurrence after MWA (p = 0.869).

Conclusions

AFP score but not AURKB can predict the risk of recurrence of HCC after MWA.

The efficacy of microwave ablation versus liver resection in the treatment of hepatocellular carcinoma and liver metastases: A systematic review and meta-analysis

BACKGROUND

Microwave ablation (MWA) is an important method in the treatment of liver cancer. This systematic review compared MWA with liver resection (LR) for liver cancer treatment. In recent years, the MWA has been also reported to play an important role. Studies comparing MWA and LR are lacking. This study aims to compare the efficacy of MWA and LR in the treatment of hepatocellular carcinoma (HCC).

METHODS

A systematic search of PubMed, Embase, Cochrane Library and Web of Science up to April 1, 2019 was conducted for relevant studies that compared the efficacy of MWA and LR in the treatment of HCC. The primary outcomes were local tumor recurrence (LTR) and overall survival (OS) of patients. The secondary outcomes included disease free survival (DFS), extrahepatic metastasis, intrahepatic de novo lesions, length of stay, complications, intraoperative blood loss and operative time.

RESULTS

A total of 16 studies including 2622 patients were identified. Incidence of LTR was significantly higher in patients with MWA than LR, with a pooled OR of 2.69 (95% CI 1.33-5.41; P = 0.006). No significant difference in 1-year OS was found. However, patients with MWA experienced higher 3- and 5-year OS, with pooled ORs of 1.40 (95% CI 1.07-1.84; P = 0.01) and 1.41 (95% CI 1.10-1.80; P = 0.007) respectively. In secondary measures, the 1- and 3-year DFS were significantly higher in patients with MWA. However, no significant difference of 5-year DFS was observed. In addition, lower incidence of complications, less intraoperative blood loss and shorter operative time and shorter length of stay were observed in MWA.

CONCLUSIONS

Though MWA may lead to higher incidence of recurrence, it may be an effective and safe alternative in patients with HCC or liver metastases. MWA may have benefits in patients' survival and safety. Randomized studies should be performed to determine the target population that benefits most from MWA in the future.

A review of conventional and newer generation microwave ablation systems for hepatocellular carcinoma

Although microwave ablation (MWA) exhibits a high thermal efficiency, the major limitation of conventional MWA systems is the lack of predictability of the ablation zone size and shape. Therefore, a specific newer generation MWA system, The Emprint™ Ablation System with Thermosphere™ Technology, was designed to create predictable large spherical zones of ablation that are not impacted by varying tissue environments. The time required for ablation with MWA systems is short, and the shape of the necrosis is elliptical with the older systems and spherical with the new system. In addition, because MWA has no heat-sink effect, it can be used to ablate tumors adjacent to major vessels. Although these factors yield a large ablation volume and result in good local control, excessive ablation of liver tissue and unexpected ablation of surrounding organs are possible. Therefore, MWA should be carefully performed. This review highlights the efficacy and complications of MWA performed with conventional systems and the newer generation system in patients with hepatocellular carcinoma (HCC). MWA with the newer generation system seems to be a promising treatment option for large HCCs and secondary hepatic malignancies, with several advantages over other available ablation techniques, including conventional MWA. However, further randomized controlled trials are necessary to fully clarify the benefits and pitfalls of this new system.

Hepatic resection versus operative microwave ablation for single hepatocellular carcinoma ≤5 cm: A propensity score-matched analysis

BACKGROUND

Little evidence exists regarding the perioperative and oncologic benefits of microwave ablation for hepatocellular carcinoma. The aim of this study was to compare the efficacy of hepatic resection and operative microwave ablation (microwave coagulo-necrotic therapy) for single hepatocellular carcinoma ≤5 cm.

METHODS

Between 1994 and 2015, a total of 551 patients with a single hepatocellular carcinoma ≤5 cm were treated in our institution (hepatic resection: n = 128; microwave coagulo-necrotic therapy: n = 423). We compared overall survival and recurrence-free survival between hepatic resection and microwave coagulo-necrotic therapy. Propensity score matching analysis identified 94 matched pairs of patients to compare outcomes.

RESULTS

After propensity score matching, baseline variables, including liver function and tumor size, were well-balanced between the 2 groups. The 5- and 10-year overall survival rates were 76% and 47% for hepatic resection and 77% and 48% for microwave coagulo-necrotic therapy, respectively (P = .865). The 5- and 10-year recurrence-free survival rates were 55% and 41% for hepatic resection and 47% and 32% for microwave coagulo-necrotic therapy, respectively (P = .377). In the subgroup analysis, the hepatic resection group had better recurrence-free survival than the microwave coagulo-necrotic therapy group in patients with tumor size >3 cm, with 5-year recurrence-free survival rates of 56.5% and 32.4% in the hepatic resection and microwave coagulo-necrotic therapy group, respectively (P = .029).

CONCLUSION

Our propensity score matching study confirmed no statistically significant differences in both overall survival and recurrence-free survival between hepatic resection and microwave coagulo-necrotic therapy for single hepatocellular carcinoma ≤5 cm; however, hepatic resection is recommended for hepatocellular carcinoma with tumor size >3 cm when patients have good liver function.

Microwave ablation compared with hepatic resection for the treatment of hepatocellular carcinoma and liver metastases: a systematic review and meta-analysis

Background

Hepatic resection (HR) is the gold standard liver cancer treatment, but few patients are eligible due to comorbidities or tumor location. Microwave ablation (MWA) is an important complementary liver cancer treatment to HR. This systematic review compared MWA with HR for liver cancer treatment.

Methods

A systematic search of MEDLINE, EMBASE, and CENTRAL was conducted for randomized and observational studies published from 2006 onwards. The primary outcome was local tumor recurrence (LTR), and a random effects model was used for meta-analyses.

Results

Of the 1845 studies identified, 1 randomized and 15 observational studies met the inclusion criteria. LTR was significantly increased with MWA versus HR (risk ratio (RR) = 2.49; P = 0.016). In secondary measures, HR provided significantly higher 3- and 5-year overall survival (RR = 0.94; P = 0.03 and RR = 0.88; P = 0.01, respectively) and 3-year disease-free survival (RR = 0.78; P = 0.009). MWA exhibited significantly shorter length of stay (weighted mean difference (WMD) = − 6.16 days; P < 0.001) and operative time (WMD = − 58.69 min; P < 0.001), less intraoperative blood loss (WMD = − 189.09 mL; P = 0.006), and fewer complications than HR (RR = 0.31; P < 0.001). When MWA was combined with HR and compared with either modality alone, complications and blood loss were significantly lower with the combination treatment; however, there were no differences in other outcomes. Subgroup and sensitivity analyses were generally aligned with the main results.

Conclusions

MWA can be an effective and safe alternative to HR in patients/tumors that are not amenable to resection. More randomized and economic studies should be performed that compare the two treatments, especially to determine the target population that benefits most from MWA.

Electronic supplementary material

The online version of this article (10.1186/s12957-019-1632-6) contains supplementary material, which is available to authorized users.

M2 macrophages mediate sorafenib resistance by secreting HGF in a feed-forward manner in hepatocellular carcinoma

Background

Sorafenib is the only approved first line systemic therapy for advanced hepatocellular carcinoma (HCC) in the last decade. Tumour resistance to sorafenib has been of major obstacles to improve HCC patient survival.

Methods

We polarised THP-1 cells to M1 and M2 macrophages, performed various in vitro assays and developed sorafenib-resistant xenograft models to investigate the role of tumour-associated macrophages (TAM)-secreted molecules in HCC resistance to the targeted therapy.

Results

We demonstrated M2, but not M1, macrophages not only promote proliferation, colony formation and migration of hepatoma cells but also significantly confer tumour resistance to sorafenib via sustaining tumour growth and metastasis by secreting hepatocyte growth factor (HGF). HGF activates HGF/c-Met, ERK1/2/MAPK and PI3K/AKT pathways in tumour cells. Tumour-associated M2 macrophages were accumulated in sorafenib-resistance tumours more than in sorafenib-sensitive tumours in vivo and produced abundant HGF. HGF chemoattracts more macrophages migrated from surrounding area, regulates the distribution of M2 macrophages and increases hepatoma resistance to sorafenib in a feed-forward manner.

Conclusions

Our results provide new insights into the mechanisms of sorafenib resistance in HCC and rationale for developing new trials by combining sorafenib with a potent HGF inhibitor such as cabozantinib to improve the first line systemic therapeutic efficacy.

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.

CT-based peritumoral radiomics signatures to predict early recurrence in hepatocellular carcinoma after curative tumor resection or ablation

OBJECTIVE

To construct a prediction model based on peritumoral radiomics signatures from CT images and investigate its efficiency in predicting early recurrence (ER) of hepatocellular carcinoma (HCC) after curative treatment.

MATERIALS AND METHODS

In total, 156 patients with primary HCC were randomly divided into the training cohort (109 patients) and the validation cohort (47 patients). From the pretreatment CT images, we extracted 3-phase two-dimensional images from the largest cross-sectional area of the tumor. A region of interest (ROI) was manually delineated around the lesion for tumoral radiomics (T-RO) feature extraction, and another ROI was outlined with an additional 2 cm peritumoral area for peritumoral radiomics (PT-RO) feature extraction. The least absolute shrinkage and selection operator (LASSO) logistic regression model was applied for feature selection and model construction. The T-RO and PT-RO models were constructed. In the validation cohort, the prediction efficiencies of the two models and peritumoral enhancement (PT-E) were evaluated qualitatively by receiver operating characteristic (ROC) curves, calibration curves and decision curves and quantitatively by area under the curve (AUC), the category-free net reclassification index (cfNRI) and integrated discrimination improvement values (IDI).

RESULTS

By comparing AUC values, the prediction accuracy in the validation cohort was good for the PT-RO model (0.80 vs. 0.79, P = 0.47) but poor for the T-RO model (0.82 vs. 0.62, P < 0.01), which was significantly overfitted. In the validation cohort, the ROC curves, calibration curves and decision curves indicated that the PT-RO model had better calibration efficiency and provided greater clinical benefits. CfNRI indicated that the PT-RO model correctly reclassified 47% of ER patients and 32% of non-ER patients compared to the T-RO model (P < 0.01); additionally, the PT-RO model correctly reclassified 24% of ER patients and 41% of non-ER patients compared to PT-E (P = 0.02). IDI indicated that the PT-RO model could improve prediction accuracy by 0.22 (P < 0.01) compared to the T-RO model and by 0.20 (P = 0.01) compared to PT-E.

CONCLUSION

The CT-based PT-RO model can effectively predict the ER of HCC and is more efficient than the T-RO model and the conventional imaging feature PT-E.

Biomarker-Driven and Molecular Targeted Therapies for Hepatobiliary Cancers

The recent accumulation of molecular profiling data for primary hepatobiliary malignancies, including hepatocellular carcinoma and biliary tract cancers, has led to a proliferation of promising therapeutic investigations in recent years. Treatment with pathway-specific targeted inhibitors and immunotherapeutic agents have demonstrated promising early clinical results. Key molecular alterations in common hepatobiliary cancers and ongoing interventional clinical trials of molecularly targeted systemic agents focusing on hepatocellular carcinoma and biliary tract cancer are reviewed.

Function of the c-Met receptor tyrosine kinase in carcinogenesis and associated therapeutic opportunities

c-Met is a receptor tyrosine kinase belonging to the MET (MNNG HOS transforming gene) family, and is expressed on the surfaces of various cells. Hepatocyte growth factor (HGF) is the ligand for this receptor. The binding of HGF to c-Met initiates a series of intracellular signals that mediate embryogenesis and wound healing in normal cells. However, in cancer cells, aberrant HGF/c-Met axis activation, which is closely related to c-Met gene mutations, overexpression, and amplification, promotes tumor development and progression by stimulating the PI3K/AKT, Ras/MAPK, JAK/STAT, SRC, Wnt/β-catenin, and other signaling pathways. Thus, c-Met and its associated signaling pathways are clinically important therapeutic targets. In this review, we elaborate on the molecular structure of c-Met and HGF and the mechanism through which their interaction activates the PI3K/AKT, Ras/MAPK, and Wnt signaling pathways. We also summarize the connection between c-Met and RON and EGFR, which are also receptor tyrosine kinases. Finally, we introduce the current therapeutic drugs that target c-Met in primary tumors, and their use in clinical research.

VEGF Overexpression Predicts Poor Survival in Hepatocellular Carcinoma

Objective

The aim of this study was to investigate the clinicopathological and immunohistochemical (including VEGF, Akt, HSP70, and HSP20 expression) factors that affect the overall and disease-free survival of HCC patients following surgical resection.

Methods

234 patients with HCC following surgical resection were enrolled. Clinicopathological and survival data were analyzed, and immunohistochemical staining was performed on tissue microarray sections using the anti-VEGF, anti-Akt, anti-HSP70, and anti-HSP27 antibodies.

Results

The 3- and 5-year overall survival rates were 86.5 and 81.54%, respectively. Multivariate analysis revealed that VEGF expression (P = 0.017, HR = 2.573) and T stage (P < 0.001, HR = 4.953) were independent prognostic factors for overall survival. Immunohistochemical staining showed that the expression of Akt, HSP70, and HSP27 did not affect the overall survival rate. The 3- and 5-year disease-free survival rates were 58.2 and 49.4%, respectively. Compared to the VEGF(−)/(+) group, the VEGF(++)/(+++) group demonstrated significantly higher proportion of patients with AFP levels > 400 ng/mL, capsule invasion, and microvascular invasion.

Conclusion

VEGF overexpression was associated with capsule invasion, microvascular invasion, and a poor overall survival rate.

Comparison of microwave ablation and hepatic resection for hepatocellular carcinoma: a meta-analysis

BACKGROUND AND AIMS

Hepatic resection (HRN) and microwave ablation (MWA) have significant advantages in treating hepatocellular carcinoma; however, it remains unclear which way produces better outcomes. This meta-analysis of cohort studies compared the treatments in terms of effectiveness and safety.

METHODS

Six electronic databases (PubMed, Medline, EMBASE, Web of Science, EBSCO, and The Cochrane Library) were retrieved for studies comparing MWA and HRN. The meta-analysis was conducted based on statement of preferred reporting items for systematic reviews and meta-analyses.

RESULTS

Nine studies met the inclusion criteria, with a total of 1,480 patients. The overall meta-analysis demonstrated no significant difference in overall survival between the MWA group and the HRN group (HR =0.98, 95% CI =0.76-1.26, P=0.878). There was no difference in disease-free survival between the MWA group and the HRN group (HR =1.16, 95% CI =0.79-1.71, P=0.442). Meanwhile, the meta-analysis demonstrated that MWA was associated with shorter operation time (standardized mean difference [SMD] =-1.37, 95% CI =-1.92 to -0.81, P=0.000), less amount of blood loss in operation (SWD =-1.19, 95% CI =-1.76 to -0.61, P=0.000), and less complications (OR =0.22, 95% CI =0.12-0.40, P=0.000) than HRN.

CONCLUSION

In conclusion, our meta-analysis suggests that MWA may be superior to HRN as it is as effective as HRN in terms of overall survival, disease-free survival, tumor recurrence, and is associated with shorter operation time, less amount of blood loss, and fewer complications.

Prognostic value of c-Met overexpression in hepatocellular carcinoma: a meta-analysis and review

The overexpression of c-Met protein has been detected in hepatocellular carcinoma (HCC). However, its prognostic impact remains uncertain. We performed this meta-analysis to evaluate the prognostic value of c-Met overexpression in patients who underwent curative surgical resection for HCC. A systematic computerized search of the electronic databases was carried out. From 5 studies, 1,408 patients who underwent surgical resection for HCC were included in the meta-analysis. Compared with patients with HCC having low c-Met expression, patients with c-Met-high tumor showed significantly worse relapse-free survival (hazard ratio = 1.26 [95% confidence interval, 1.02–1.56], P = 0.03) and overall survival (hazard ratio = 1.16 [95% confidence interval, 1.03–1.31], P = 0.01). In conclusion, our meta-analysis indicates that c-Met overexpression is a significant adverse prognostic factor for recurrence and survival in patients who underwent surgical resection for HCC.

Microwave ablation combined with OK-432 induces Th1-type response and specific antitumor immunity in a murine model of breast cancer

Background

Minimally invasive therapies, such as microwave ablation (MWA), are widely used for the treatment of solid tumors. Previous studies suggest that MWA is feasible for the treatment of small breast cancer, and thermal ablation may induce adaptive antitumor immunity. However, the induced immune responses are mostly weak, and the immunomodulation effects of MWA in breast cancer are unclear. Immunostimulant OK-432 can induce tumor-specific T-cell responses and may augment the immunity induced by MWA.

Methods

We treated 4T1 breast cancer bearing BALB/c mice with MWA, OK-432, MWA plus OK-432, or left without treatment. Survival time was evaluated with the Kaplan–Meyer method comparing survival curves by log-rank test. On day 25 after ablation, surviving mice received tumor rechallenge, and the rechallenged tumor volumes were calculated every 5 days. Immunohistochemistry and flow cytometry were used to evaluate the T-cell immune responses in ablated tissues and spleens. The tumor-specific immunity was assessed by enzyme-linked immunospot assays. Besides, the cytokine patterns were identified from enzyme-linked immunosorbent assay.

Results

Microwave ablation plus OK-432 resulted in longer survival than single treatment and protect most surviving mice from tumor rechallenge. Both local and systemic T-cell responses were induced by MWA and were further enhanced by subsequent administration of OK-432. Moreover, the combination of MWA and OK-432 induced stronger tumor-specific immune responses than MWA alone. In addition, OK-432 and MWA synergistically promoted the production of Th1-type but not Th2-type cytokines, and polarized T-cell responses to Th1-dominant state.

Conclusions

The T-cell immune responses were activated by MWA in breast cancer. Furthermore, the combination of MWA and OK-432 induced Th1-type response and elicited specific antitumor immunity.

Status and advancement of microwave ablation in China

Tumour ablation is defined as the direct application of chemical or thermal therapy to eradicate or substantially destroy a tumour. Currently, minimally invasive ablation techniques are available for the local destruction of focal tumours in multiple organ sites. Microwave ablation (MWA) is premised on the biological response of solid tumours to tissue hyperthermia, and it is a relatively low-risk procedure. Due to several advantages of MWA, including higher thermal efficiency, higher capability for coagulating blood vessels, faster ablation time and the simultaneous application of multiple antennae, MWA could be a promising minimally invasive ablation technique for the treatment of solid tumours. Therefore, the use of MWA has developed rapidly in China during the last decade. Many successful studies have been performed, and widespread use has been achieved for multiple types of tumours in China, especially for liver cancer. This review will describe the state-of-the-art of MWA in China, including the development of MWA equipment and its application in the treatment of multiple types of tumours.

Current role of microwave ablation in the treatment of small hepatocellular carcinomas

Percutaneous radiofrequency ablation (RFA) can be as effective as surgical resection in terms of overall survival and recurrence-free survival rates in patients with small hepatocellular carcinoma (HCC). Effectiveness of RFA is adversely influenced by heat-sink effect. Other ablative therapies could be considered for larger tumors or for tumors located near the vessels. In this regard, recent improvements in microwave energy delivery systems seem to open interesting perspectives to percutaneous ablation, which could become the ablation technique of choice in the near future. Microwave ablation (MWA) has the advantages of possessing a higher thermal efficiency. It has high efficacy in coagulating blood vessels and is a relatively fast procedure. The time required for ablation is short and the shape of necrosis is elliptical with the older systems and spherical with the new one. There is no heat-sink effect and it can be used to ablate tumors adjacent to major vessels. These factors yield a large ablation volume, and result in good local control and fewer complications. This review highlights the most relevant updates on MWA in the treatment of small (<3 cm) HCC. Furthermore, we discuss the possibility of MWA as the first ablative choice, at least in selected cases.

Biomarker development in MET-targeted therapy

Activation of the MET receptor tyrosine kinase by its ligand, hepatocyte growth factor (HGF), has been implicated in a variety of cellular processes, including cell proliferation, survival, migration, motility and invasion, all of which may be enhanced in human cancers. Aberrantly activated MET/HGF signaling correlates with tumorigenesis and metastasis, and is regarded as a robust target for the development of novel anti-cancer treatments. Various clinical trials were conducted to evaluate the safety and efficacy of selective HGF/MET inhibitors in cancer patients. There is currently no optimal or standardized method for accurate and reliable assessment of MET levels, or other biomarkers that are predictive of the patient response to MET-targeted therapeutics. In this review, we discuss the importance of accurate HGF/MET signal detection as a predictive biomarker to guide patient selection for clinical trials of MET-targeted therapies in human cancers.

Radiofrequency and microwave ablation in combination with transarterial chemoembolization induce equivalent histopathologic coagulation necrosis in hepatocellular carcinoma patients bridged to liver transplantation

BACKGROUND

Bridging therapy plays an increasingly important role in the management of patients with hepatocellular carcinoma (HCC) awaiting liver transplantation (LT). Combination therapy with drug-eluting bead transarterial chemoembolization (DEB-TACE) and percutaneous thermal ablation, such as radiofrequency ablation (RFA) or microwave ablation (MWA), has shown success at prolonging survival and bridging patients to LT. However, few studies have evaluated the two combination therapy regimens head-to-head at a single institution, and fewer have compared histopathology. This retrospective study compares tumor coagulation on explanted livers in patients with HCC treated with DEB-TACE sequentially combined with RFA versus MWA.

METHODS

From 2005 to 2015, 42 sequential patients underwent combination therapy prior to LT by Milan criteria, with 11 patients (11 tumors; mean, 2.9 cm; range, 1.8-4.3 cm) in the DEB-TACE/RFA cohort and 31 patients (40 tumors; mean, 2.4 cm; range, 1.1-5.4 cm) in the DEB-TACE/MWA cohort. The mean TACE procedures in the RFA and MWA cohorts were 1.3 (range, 1-2) and 1.3 (range, 1-3), respectively. The mean thermal ablations in the RFA and MWA cohorts were 1.2 (range, 1-2) and 1.3 (range, 1-3), respectively. Tumor coagulation was evaluated on explanted livers.

RESULTS

Mean tumor coagulation in the RFA and MWA cohorts were 88.9% (range, 0-100%) and 90.5% (range, 30-100%), respectively (P=0.82). Rates of complete tumor coagulation in the RFA and MWA cohorts were 45% and 53%, respectively (P=0.74). No difference in tumor coagulation was found between the cohorts when separating tumors <3 cm (P=0.21) and >3 cm (P=0.09). Among all 51 tumors, the 36 in complete response (CR) on imaging at LT demonstrated mean tumor coagulation of 95.8%. No correlation was found between tumor coagulation and initial tumor size or time interval to LT. No tumor seeding was seen along the ablation tracts.

CONCLUSIONS

RFA and MWA in sequential combination with DEB-TACE, used as a bridge to LT, are equally efficacious at inducing HCC tumor coagulation.

Gene of the month: HGF

Hepatocyte growth factor (HGF) is a multifunctional cytokine with important roles in cell proliferation, survival, motility and morphogenesis. Secreted by cells of mesenchymal origin, HGF is the specific ligand for the tyrosine-kinase receptor c-MET (cellular mesenchymal-epithelial transition), also called MET, which is expressed in different types of epithelial, endothelial and haematopoietic progenitor cells. The HGF/MET axis is involved in several biological processes, such as embryogenesis, organogenesis, adult tissue regeneration (including wound healing and liver regeneration) and carcinogenesis, for both solid and haematological malignancies.1 2 HGF and its particular interaction with the MET receptor have been extensively investigated in the last decades and remain the focus of numerous clinical trials.3–8 This short review focuses on HGF structure and function, as well as its roles in liver regeneration and different types of tumours.

Preclinical Evaluation of AMG 337, a Highly Selective Small Molecule MET Inhibitor, in Hepatocellular Carcinoma

Aberrant hepatocyte growth factor (HGF)/MET signaling has been implicated in hepatocarcinogenesis, suggesting that MET may serve as an attractive therapeutic target in hepatocellular carcinoma. We sought to investigate the in vitro and in vivo antitumor activity of AMG 337, a potent and highly selective small molecule MET kinase inhibitor, in preclinical models of hepatocellular carcinoma. The antiproliferative activity of AMG 337 was evaluated across a panel of hepatocellular carcinoma cell lines in a viability assay. Daily oral administration was used to evaluate the in vivo antitumor activity of AMG 337 in two patient-derived xenograft (PDX) models of hepatocellular carcinoma (LI0612 and LI1078). AMG 337 exerted potent antiproliferative activity against 2 of 40 hepatocellular carcinoma cell lines, namely, MHCC97H (IC50, 0.015 μmol/L) and HCCLM3 (IC50, 0.025 μmol/L). Both sensitive cell lines showed MET amplification (MET/CEN-7 >2.0) assessed by FISH, and high MET expression (3+ IHC) assessed by IHC. AMG 337 potently inhibited p-MET in all cell lines with detectable levels of total MET. However, the dose-dependent inhibition of downstream effectors of HGF/MET signaling, including p-GAB1, p-AKT, and p-ERK, was limited to those cell lines sensitive to AMG 337 in a viability assay (MHCC97H and HCCLM3). AMG 337 significantly inhibited tumor growth at all doses tested in the MET-amplified and MET-high-expressing hepatocellular carcinoma PDX model LI0612 and had no effect on tumor growth in the non-MET-amplified and MET-low-expressing hepatocellular carcinoma PDX model LI1078. AMG 337 represents a promising and novel therapeutic strategy for targeting hepatocellular carcinomas with a dependence on HGF/MET signaling. Mol Cancer Ther; 15(6); 1227-37. ©2016 AACR.

Impact of MET targeting on tumor-associated angiogenesis and growth of MET mutations-driven models of liver cancer

Deregulated expression of the MET receptor tyrosine kinase has been reported in up to 50% of patients with hepatocellular carcinoma, the most abundant form of liver cancers, and is associated with decreased survival. Consequently, MET is considered as a molecular target in this malignancy, whose progression is highly dependent on extensive angiogenesis. Here we studied the impact of MET small molecule inhibitors on angiogenesis-associated parameters and growth of xenograft liver models consisting of cells expressing MET-mutated variants M1268T and Y1248H, which exhibit constitutive kinase activity. We demonstrate that MET mutations expression is associated with significantly increased production of vascular endothelial growth factor, which is blocked by MET targeting only in cells expressing the M1268T inhibitor-sensitive but not in the Y1248H inhibitor-resistant variant. Decrease in vascular endothelial growth factor production is also associated with reduction of tyrosine phopshorylation of the vascular endothelial growth factor receptor 2 expressed on primary liver sinusoidal endothelial cells and with inhibition of vessel formation. Furthermore, MET inhibition demonstrated an efficient anti-tumor activity and considerable reduction in microvessel density only against the M1268T-derived intrahepatic tumors. Collectively, our data support the role of targeting MET-associated angiogenesis as a major biological determinant for liver tumor growth control.

The EGFR/ErbB3 Pathway Acts as a Compensatory Survival Mechanism upon c-Met Inhibition in Human c-Met+ Hepatocellular Carcinoma

Background

c-Met, a high-affinity receptor for Hepatocyte Growth Factor (HGF), plays a critical role in tumor growth, invasion, and metastasis. Hepatocellular carcinoma (HCC) patients with activated HGF/c-Met signaling have a significantly worse prognosis. Targeted therapies using c-Met tyrosine kinase inhibitors are currently in clinical trials for HCC, although receptor tyrosine kinase inhibition in other cancers has demonstrated early success. Unfortunately, therapeutic effect is frequently not durable due to acquired resistance.

Methods

We utilized the human MHCC97-H c-Met positive (c-Met⁺) HCC cell line to explore the compensatory survival mechanisms that are acquired after c-Met inhibition. MHCC97-H cells with stable c-Met knockdown (MHCC97-H c-Met KD cells) were generated using a c-Met shRNA vector with puromycin selection and stably transfected scrambled shRNA as a control. Gene expression profiling was conducted, and protein expression was analyzed to characterize MHCC97-H cells after blockade of the c-Met oncogene. A high-throughput siRNA screen was performed to find putative compensatory survival proteins, which could drive HCC growth in the absence of c-Met. Findings from this screen were validated through subsequent analyses.

Results

We have previously demonstrated that treatment of MHCC97-H cells with a c-Met inhibitor, PHA665752, results in stasis of tumor growth in vivo. MHCC97-H c-Met KD cells demonstrate slower growth kinetics, similar to c-Met inhibitor treated tumors. Using gene expression profiling and siRNA screening against 873 kinases and phosphatases, we identified ErbB3 and TGF-α as compensatory survival factors that are upregulated after c-Met inhibition. Suppressing these factors in c-Met KD MHCC97-H cells suppresses tumor growth in vitro. In addition, we found that the PI3K/Akt signaling pathway serves as a negative feedback signal responsible for the ErbB3 upregulation after c-Met inhibition. Furthermore, in vitro studies demonstrate that combination therapy with PHA665752 and Gefitinib (an EGFR inhibitor) significantly reduced cell viability and increased apoptosis compared with either PHA665752 or Gefitinib treatment alone.

Conclusion

c-Met inhibition monotherapy is not sufficient to eliminate c-Met⁺ HCC tumor growth. Inhibition of both c-Met and EGFR oncogenic pathways provides superior suppression of HCC tumor growth. Thus, combination of c-Met and EGFR inhibition may represent a superior therapeutic regimen for c-Met⁺ HCC.

c-MET receptor tyrosine kinase as a molecular target in advanced hepatocellular carcinoma

c-MET is the membrane receptor for hepatocyte growth factor (HGF), also known as scatter factor or tumor cytotoxic factor, a mitogenic growth factor for hepatocytes. HGF is mainly produced by cells of mesenchymal origin and it mainly acts on neighboring epidermal and endothelial cells, regulating epithelial growth and morphogenesis. HGF/MET signaling has been identified among the drivers of tumorigenesis in human cancers. As such, c-MET is a recognized druggable target, and against it, targeted agents are currently under clinical investigation. c-MET overexpression is a common event in a wide range of human malignancies, including gastric, lung, breast, ovary, colon, kidney, thyroid, and liver carcinomas. Despite c-MET overexpression being reported by a large majority of studies, no evidence for a c-MET oncogenic addiction exists in hepatocellular carcinoma (HCC). In particular, c-MET amplification is a rare event, accounting for 4%–5% of cases while no mutation has been identified in c-MET oncogene in HCC. Thus, the selection of patient subgroups more likely to benefit from c-MET inhibition is challenging. Notwithstanding, c-MET overexpression was reported to be associated with increased metastatic potential and poor prognosis in patients with HCC, providing a rationale for its therapeutic inhibition. Here we summarize the role of activated HGF/MET signaling in HCC, its prognostic relevance, and the implications for therapeutic approaches in HCC.

Clinical outcome of medium-sized hepatocellular carcinoma treated with microwave ablation

AIM: To evaluate the outcomes of patients with medium-sized hepatocellular carcinoma (HCC) who underwent percutaneous microwave ablation (MWA).

METHODS: We retrospectively reviewed all patients with a single medium-sized HCC who underwent percutaneous MWA from January 2010 to January 2013. Technical success, technical effectiveness and complications were subsequently observed. Survival curves were constructed using the Kaplan-Meier method. The Cox proportional hazards model was fitted to each variable. The relative prognostic significance of the variables for predicting overall survival rate, recurrence-free survival rate and local tumor recurrence(s) was assessed using univariate analysis. All variables with a P value < 0.20 were subjected to multivariate analysis.

RESULTS: The study included 182 patients (mean age, 58 years; age range: 22-86 years) with a single HCC (mean size, 3.72 ± 0.54 cm; range: 3.02-5.00 cm). The estimated technical effectiveness rate was 93% in 182 patients. The major complication rate was 2.7% (5/182), including liver abscess in 4 cases, and abdominal bleeding at the puncture site in 1 case. Thirty-day mortality rate was 0.5% (1/182). One patient died due to liver abscess-related septicemia. Cumulative recurrence-free survival and overall survival (OS) rates were 51%, 36%, 27% and 89%, 74%, 60% at 1, 2, and 3 years, respectively. Age (P = 0.017) and tumor diameter (P = 0.029) were independent factors associated with local tumor recurrence. None of the factors had a statistically significant impact on recurrence-free survival. Serum albumin level (P = 0.009) and new lesion(s) (P = 0.029) were independently associated with OS.

CONCLUSION: Percutaneous MWA is a relatively safe and effective treatment for patients with medium-sized HCC.

Preclinical trials for prevention of tumor progression of hepatocellular carcinoma by LZ-8 targeting c-Met dependent and independent pathways

Hepatocellular carcinoma (HCC) is among the most lethal cancers. Mounting studies highlighted the essential role of the HGF/c-MET axis in driving HCC tumor progression. Therefore, c-Met is a potential therapeutic target for HCC. However, several concerns remain unresolved in c-Met targeting. First, the status of active c-Met in HCC must be screened to determine patients suitable for therapy. Second, resistance and side effects have been observed frequently when using conventional c-Met inhibitors. Thus, a preclinical system for screening the status of c-Met signaling and identifying efficient and safe anti-HCC agents is urgently required. In this study, immunohistochemical staining of phosphorylated c-Met (Tyr1234) on tissue sections indicated that HCCs with positive c-Met signaling accounted for approximately 46% in 26 cases. Second, many patient-derived HCC cell lines were established and characterized according to motility and c-Met signaling status. Moreover, LZ8, a medicinal peptide purified from the herb Lingzhi, featuring immunomodulatory and anticancer properties, was capable of suppressing cell migration and slightly reducing the survival rate of both c-Met positive and negative HCCs, HCC372, and HCC329, respectively. LZ8 also suppressed the intrahepatic metastasis of HCC329 in SCID mice. On the molecular level, LZ8 suppressed the expression of c-Met and phosphorylation of c-Met, ERK and AKT in HCC372, and suppressed the phosphorylation of JNK, ERK, and AKT in HCC329. According to receptor array screening, the major receptor tyrosine kinase activated in HCC329 was found to be the epidermal growth factor receptor (EGFR). Moreover, tyrosine-phosphorylated EGFR (the active EGFR) was greatly suppressed in HCC329 by LZ8 treatment. In addition, LZ8 blocked HGF-induced cell migration and c-Met-dependent signaling in HepG2. In summary, we designed a preclinical trial using LZ8 to prevent the tumor progression of patient-derived HCCs with c-Met-positive or -negative signaling.

Preoperative ultrasound features as prognostic factors for patients with hepatocellular carcinoma

PURPOSE

Ultrasound is the most common imaging tool used to scan the tumours of hepatic carcinoma patients. However, very few studies have been performed to evaluate ultrasound imaging features for predicting tumour prognosis. Therefore, the goal of the current study was to evaluate preoperative ultrasound characteristics as prognostic factors that could affect survival rate after liver resection for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

A total of 104 HCC patients who underwent resection were retrospectively reviewed with regard to their clinical data, preoperative ultrasound characteristics, and survival rate. Preoperative ultrasound parameters included cirrhosis, tumour site, size, echo pattern, portal vein thrombosis, intra-tumour blood flow signal, peak systolic velocity (V max), and resistance index (RI). The Kaplan-Meier method was used to calculate survival. Pre-resection prognostic factors were assessed using univariate log-rank test and a multivariate Cox proportional hazards model.

RESULTS

The median survival was 37 months. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 78.85, 53.85, and 26.92 %, respectively, and the overall survival (OS) rates at 1, 3, and 5 years were 85.58, 69.23, and 46.15 %, respectively. On univariate analysis, shorter survival was associated with mixed echo pattern, larger tumour size, portal vein thrombus, affluent flow signal, and higher V max. Application of the Cox multivariate proportional hazards model indicated that tumour size and blood flow signal in the tumours were independent prognostic factors.

CONCLUSIONS

The overall survival for HCC patients undergoing hepatic resection can be stratified on a sonographic basis of tumour size and intra-nodular vasculature. These prognostic factors may be useful to determine appropriate treatment for HCC patients.

Review of angiogenesis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a hypervascular tumor, and its vascularity is unique and greatly different from peripheral parenchyma of liver. Afferent and efferent vessels of HCC lesions come to differ as the lesion develops. The characteristic of the flow regulates the common style of metastasis. The portal tract of the HCC lesion is the first site of the intrahepatic metastasis, because cancer cells roll into the portal vein via efferent flow. On microscopic observation, HCC displays marked vascular abnormalities, arteriogenesis and capillarization. Arteriogenesis is defined as the growth of functional collateral arteries covered with smooth muscle cells from pre-existing arteries. Sinusoidal capillarization involves the transformation of fenestrated hepatic sinusoids into continuous capillaries. Several angiogenic factors have been reported, and some of them are studied as prognostic factors or target molecules of chemotherapeutic reagents. However, the mechanism of neovascularization during HCC development is still unclear. This review discusses the characteristics of angiogenesis in HCC and known angiogenic factors of HCC.

A simulator for percutaneous hepatic microwave thermal ablation under ultrasound guidance

The purpose of this study was to provide a simulation therapy environment for microwave thermal ablation (MWA) under the guidance of ultrasound, and to present an inexpensive and portable simulator built on real patient-based pre-operative computed tomography (CT) data. We established an experimental simulation system for teaching MWA and present the results of a preliminary evaluation of the simulator's realism and utility for training. The system comprises physical elements of an electromagnetic tracking device and an abdominal phantom, and software elements providing three-dimensional (3D) image processing tools, real-time navigation functions and objective evaluation function module. Details of the novel aspects of this system are presented, including a portable electromagnetic tracking device, adoption of real patient-based pre-operative CT data of liver, operation simulation of MWA, and recording and playback of the operation simulation. Patients with liver cancer were selected for evaluation of the clinical application value of the experimental simulation system. A total of 50 consultant interventional radiologists and 20 specialist registrars in radiology rated the simulator's hardware reality and overall ergonomics. Results show that the simulator system we describe can be used as a training tool for MWA. It enables training with real patient cases prior to surgery, and it can provide a realistic simulation of the actual procedure.

Dissecting signaling pathways in hepatocellular carcinoma: new perspectives in medical therapy

Prognosis of patients with advanced hepatocellular carcinoma (HCC) is poor and is largely influenced by associated liver comorbidities. Moreover, effective treatment alternatives are limited; with the exception of the multitargeted inhibitor sorafenib, established options in the treatment of advanced HCC no longer amenable with ablative or locoregional procedures are lacking. In light of the limited efficacy of chemotherapy in this setting, great efforts have been made in the definition of targetable molecular pathways with a central role in the progression of HCC. Targeting angiogenesis, growth factor receptors, intracellular transduction pathways, or mechanisms of gene-expression regulation represents the main way to improve patient outcome. At the same time, identifying clinical and biological factors, which may help selecting patients with higher chances of benefit, is essential in order to hasten drug development and maximize treatment efficacy.

Role of local ablative therapy for hepatocellular carcinoma

Percutaneous local ablation (PLA) techniques are currently considered as the best treatment option for patients with early-stage hepatocellular carcinoma (HCC) who are not candidates for surgical resection. They are safe, minimally invasive, efficacious and cost-effective. Radiofrequency ablation (RFA) is considered as the first line treatment in some centers, though most of the guidelines recommend it for small HCCs, where surgical resection is not feasible. In developing countries percutaneous ethanol injection (PEI) and percutaneous acetic acid injection (PAI) may be used instead of RFA. For large HCCs, advances in electrode designs and newer techniques of ablation, including microwave ablation, are increasingly been used. Combination treatment modalities have shown promising results as compared to single modality for large tumors. The selection of the most appropriate modality depends on the size, number of lesions, the liver function status, patient's financial resources, availability of a particular technique and the expertise available.

Comparison of microwave ablation and surgical resection for treatment of hepatocellular carcinomas conforming to Milan criteria

BACKGROUND AND AIM

To compare the efficacy of microwave ablation (MWA) and surgical resection (RES) in the treatment of hepatocellular carcinoma (HCC) conforming to Milan criteria.

METHODS

Two hundred twenty-four patients met the inclusion criteria and were enrolled in the study. One hundred and seventeen patients received MWA, and 107 patients underwent RES. The primary endpoints were overall survival (OS) and disease-free survival (DFS).

RESULTS

The 1-, 3-, and 5-year OS rates were 94%, 70%, 52% for the MWA group and 94%, 72%, 60% for the RES group (P = 0.513). The corresponding DFS rates for the two groups were 77%, 38%, 18% and 85%, 57%, 31% (P = 0.005). In subgroup analyses of patients with solitary HCC ≤ 3 cm, there were no significant differences in OS rates and DFS rates between the two groups (P = 0.577 and P = 0.140). For patients with solitary HCC 3 to 5 cm, there was no significant differences in OS rates between the two groups (P = 0.820), the DFS rates was significantly higher in the RES group than in the MWA group (P = 0.014).

CONCLUSIONS

MWA results in lower DFS rates than RES for HCC conforming to Milan criteria. However, the OS rates are comparable between the two therapies. For solitary HCC ≤ 3 cm, MWA is as effective as RES.

Emerging molecular targets in oncology: clinical potential of MET/hepatocyte growth-factor inhibitors

The MET/hepatocyte growth-factor (HGF) signaling pathway plays a key role in the processes of embryogenesis, wound healing, and organ regeneration. Aberrant activation of MET/HGF occurs through multiple mechanisms including gene amplification, mutation, protein overexpression, and abnormal gene splicing interrupting autocrine and paracrine regulatory feedback mechanisms. In many cancers including non-small-cell lung cancer, colorectal, gastric, renal, and hepatocellular cancer, dysregulation of MET may lead to a more aggressive cancer phenotype and may be a negative prognostic indicator. Successful therapeutic targeting of the MET/HGF pathway has been achieved using monoclonal antibodies against the MET receptor and its ligand HGF in addition to MET-specific and multitargeted small-molecule tyrosine-kinase inhibitors with several drugs in late-phase clinical trials including onartuzumab, rilotumumab, tivantinib, and cabozantinib. MET frequently interacts with other key oncogenic tyrosine kinases including epidermal growth-factor receptor (EGFR) and HER-3 and these interactions may be responsible for resistance to anti-EGFR therapies. Similarly, resistance to MET inhibition may be mediated through EGFR activation, or alternatively by increasing levels of MET amplification or acquisition of novel "gatekeeper" mutations. In order to optimize development of effective inhibitors of the MET/HGF pathway clinical trials must be enriched for patients with demonstrable MET-pathway dysregulation for which robustly standardized and validated assays are required.