Des-gamma-carboxy prothrombin increases the expression of angiogenic factors in human hepatocellular carcinoma cells

Diagnostic performance of PIVKA-II in identifying recurrent hepatocellular carcinoma following curative resection: a retrospective cohort study

Protein induced by vitamin K absence or antagonist II (PIVKA-II) plays a critical role in the diagnosis of hepatocellular carcinoma (HCC), however, studies on its efficacy in diagnosing recurrent HCC were rarely found. A multicenter, retrospective, and observational study was conducted. During the overall follow-up of 5 years, HCC patients who had curative resection were monitored every 3 months in the first year post-surgery and every 6 months thereafter if no recurrence occurred. Tumor markers were collected at the diagnosis of recurrence for those with recurrence and at the last follow-up for those without recurrence. The median serum levels of PIVKA-II and AFP in the recurrence group were significantly higher than those in the non-recurrence group (PIVKA-II: 84.62 vs. 18.76 mAU/ml, p < 0.001; AFP: 4.90 vs. 3.00 ng/ml, p < 0.001) and there is a significant correlation between PIVKA-II and AFP (R = 0.901, p < 0.001). PIVKA-II showed better accuracy than AFP in the diagnosis of overall recurrent HCC (AUC: 0.883 vs. 0.672; p < 0.0001), but also in patients with negative PIVKA-II before curative resection (AUC: 0.878 vs. 0.680, p = 0.001). Clinician should pay more attention to serum PIVKA-II values when following patients after curative HCC resection to detect early recurrence.Clinical trial registration: ChiCTR2300070874.

The Current Status of the Liver Liquid Biopsy in MASH Related HCC: Overview and Future Directions

Metabolic dysfunction-associated steatohepatitis (MASH) is one of the major risk factors for chronic liver disease and hepatocellular carcinoma (HCC). The incidence of MASH in Western countries continues to rise, driving HCC as the third cause of cancer-related death worldwide. HCC has become a major global health challenge, partly from the obesity epidemic promoting metabolic cellular disturbances but also from the paucity of biomarkers for its early detection. Over 50% of HCC cases are clinically present at a late stage, where curative measures are no longer beneficial. Currently, there is a paucity of both specific and sensitive biological markers for the early-stage detection of HCC. The search for biological markers in the diagnosis of early HCC in high-risk populations is intense. We described the potential role of surrogates for a liver biopsy in the screening and monitoring of patients at risk for nesting HCC.

Microvascular invasion risk scores affect the estimation of early recurrence after resection in patients with hepatocellular carcinoma: a retrospective study

BACKGROUND

Microvascular invasion (MVI) is a histological factor that is closely related to the early recurrence of hepatocellular carcinoma (HCC) after resection. To investigate whether a noninvasive risk score system based on MVI status can be established to estimate early recurrence of HCC after resection.

METHODS

Between January 2018 to March 2021, a total of 108 patients with surgically treated single HCC was retrospectively included in our study. Fifty-one patients were pathologically confirmed with MVI and 57 patients were absent of MVI. Univariate and multivariate logistic regression analysis of preoperative laboratory and magnetic resonance imaging (MRI) features were used to screen noninvasive risk factors in association with MVI in HCC. Risk scores based on the odds ratio (OR) values of MVI-related risk factors were calculated to estimate the early recurrence after resection of HCC.

RESULTS

In multivariate logistic regression analysis, tumor size > 2 cm (P = 0.024, OR 3.05, 95% CI 1.19-11.13), Prothrombin induced by vitamin K absence-II > 32 mAU/ml (P = 0.001, OR 4.13, 95% CI 1.23-11.38), irregular tumor margin (P = 0.018, OR 3.10, 95% CI 1.16-8.31) and apparent diffusion coefficient value < 1007 × 10^- 3mm²/s (P = 0.035, OR 2.27, 95% CI 1.14-7.71) were independent risk factors correlated to MVI in HCC. Risk scores of patients were calculated and were then categorized into high or low-risk levels. In multivariate cox survival analysis, only high-risk score of MVI was the independent risk factor of early recurrence (P = 0.009, OR 2.11, 95% CI 1.20-3.69), with a sensitivity and specificity of 0.52, 0.88, respectively.

CONCLUSION

A risk score system based on MVI status can help stratify patients in high-risk of early recurrence after resection of HCC.

Liver Transplantation for Hepatocellular Carcinoma: How Should We Improve the Thresholds?

Simple Summary

The ideal treatment for hepatocellular carcinoma (HCC) is liver transplantation (LT), which both eliminates the HCC and cures the diseased liver. Once considered an experimental treatment with dismal survival rates, LT for HCC entered a new era with the establishment of the Milan criteria over 20 years ago. However, over the last two decades, the Milan criteria, which are based on tumor morphology, have come under intense scrutiny and are now largely regarded as too restrictive, and limit the access of transplantation for many patients who would otherwise achieve good clinical outcomes. The liver transplant community has been making every effort to reach a goal of establishing more reliable selection criteria. This article addresses how the criteria have been extended, as well as the concept of pre-transplant down-staging to maximize the eligibility.

Abstract

Hepatocellular carcinoma (HCC) is the third highest cause of cancer-related mortality, and liver transplantation is the ideal treatment for this disease. The Milan criteria provided the opportunity for HCC patients to undergo LT with favorable outcomes and have been the international gold standard and benchmark. With the accumulation of data, however, the Milan criteria are not regarded as too restrictive. After the implementation of the Milan criteria, many extended criteria have been proposed, which increases the limitations regarding the morphological tumor burden, and incorporates the tumor’s biological behavior using surrogate markers. The paradigm for the patient selection for LT appears to be shifting from morphologic criteria to a combination of biologic, histologic, and morphologic criteria, and to the establishment of a model for predicting post-transplant recurrence and outcomes. This review article aims to characterize the various patient selection criteria for LT, with reference to several surrogate markers for the biological behavior of HCC (e.g., AFP, PIVKA-II, NLR, 18F-FDG PET/CT, liquid biopsy), and the response to locoregional therapy. Furthermore, the allocation rules in each country and the present evidence on the role of down-staging large tumors are addressed.

The potential of PIVKA-II as a treatment response biomarker in hepatocellular carcinoma: a prospective United Kingdom cohort study

Prothrombin induced by vitamin K absence II (PIVKA-II) has recently been validated internationally as a diagnostic biomarker for hepatocellular carcinoma (HCC), as part of the GALAD model. However, its role as a treatment response biomarker has been less well explored. We, therefore, undertook a prospective study at a tertiary centre in the UK to evaluate the role of PIVKA-II as a treatment response biomarker in patients with early, intermediate and advanced stage HCC. In a cohort of 141 patients, we found that PIVKA-II levels tracked concordantly with treatment response in the majority of patients, across a range of different treatment modalities. We also found that rises in PIVKA-II levels almost always predated radiological progression. Among AFP non-secretors, PIVKA-II was found to be informative in 60% of cases. In a small cohort of patients undergoing liver transplantation, pre-transplant PIVKA-II levels predicted for microvascular invasion and poorer differentiation. Our results demonstrate the potential utility of PIVKA-II as a treatment response biomarker and in predicting microvascular invasion, in a Western population. PIVKA-II demonstrated improved performance over AFP but, as a single biomarker, its performance was still limited. Further larger prospective studies are recommended to evaluate PIVKA-II as a treatment response biomarker, within the GALAD model.

PIVKA-II level is correlated to development of portal vein tumor thrombus in patients with HBV-related hepatocellular carcinoma

Aim

To evaluate the correlation of serum PIVKA-II levels and development of portal vein tumor thrombus (PVTT) in hepatocellular carcinoma (HCC) patients.

Methods

One hundred and twenty-three patients with newly diagnosed HCC were included in this study between March 2016 and October 2018. Thirty-five of these patients were detected with PVTT and all subjects were randomly divided to analysis group (N = 73) and validation (N = 50) group. Serum levels of PIVKA-II, laboratory tests including serum aspartate aminotransferase, total bilirubin, platelet count, albumin levels were demonstrated in all the patients. T-test, chi-squared test and logistic regression was used for analyzing data. Diagnostic efficiency and cut-off value of PIVKA-II in PVTT development of HCC patients were calculated using receiver operator curve (ROC) analysis.

Results

Serum level of PIVKA-II in HCC patients with PVTT was significantly higher than that in HCC patients without PVTT (995.8 mAU/ml vs 94.87 mAU/ml; P = 0.003), as well as D-dimer levels (2.12 mg/L vs 0.56 mg/L P = 0.001). Univariate analysis showed that high serum D-dimer level was an independent risk factor for development of PVTT (OR = 1.22, 95%CI 1.02-1.45). ROC curve showed that among analysis group, the area under ROC curve (AUROC) of PIVKA-II was 0.73 (95%CI 0.59-0.86). For the detection of PVTT in HCC, PIVKA-II had a sensitivity of 83.7% and a specificity of 69.2% at a cutoff of 221.26 mAU/ml, which had a sensitivity of 85.71% and a specificity of 55.56% in validation group, respectively.

Conclusion

Serum PIVKA-II level is a potential marker for diagnosis of PVTT in HCC patients, which may guide therapeutic strategy and assessment of tumor prognosis of HCC.

Diagnostic value of serum PIVKA-II levels for BCLC early hepatocellular carcinoma and correlation with HBV DNA

BACKGROUND

It is reported that prothrombin induced by vitamin K absence-II (PIVKA-II) has a better performance of diagnosis for HCC, and has also been known to be an independent risk factor for vascular invasion. Few studies study the relationship between PIVKA-II and HBV DNA.

OBJECTIVE

To determine the clinical value of serum Prothrombin induced by vitamin K absence-II (PIVKA-II) in early hepatocellular carcinoma (HCC), and to explore its relationship with vascular invasion and HBV DNA.

METHODS

In a Chinese cohort, we conducted a case-control study to compare the performances of a-fetoprotein (AFP) and PIVKA-II serum levels for diagnosis of HCC and early HCC. Fifty one healthy controls, 37 chronic hepatitis patients, 43 cirrhotic patients and 143 HCC cases of which 48 (33.57%) had early stage HCC (n= 19 very early, n= 29 early) were enrolled. We explored the correlation between PIVKA-II serum level and several pathological features such as vascular invasion. The serum levels of and AFP were measured by chemiluminescence assay (CLIA) and electrochemiluminescence assay (ECLA).

RESULTS

The serum levels of both PIVKA-II and AFP in HCC group were higher than that in chronic hepatitis, cirrhosis and healthy control groups. The sensitivity, specificity, positive predictive value, negative predictive value and kappa of PIVKA-II were higher than AFP in the diagnosis of HCC. Serum PIVKA-II level was correlated with tumor size, tumor cell differentiation and BCLC staging (P< 0.05). For the diagnosis of early HCC, the combination of PIVKA-II (AUC 0.812; 95% CI, 0.702-0.894) and AFP (0.797; 95% CI, 0.686-0.883) slightly improve the diagnostic performance for early HCC(AUC 0.849; 95% CI, 0.745-0.923). PIVKA-II > 166 mAU/ml is an independent risk factor for vascular invasion. The serum HBV DNA level in cirrhosis and HCC patients was significantly higher than in chronic hepatitis patients. We detected a negative association between serum PIVKA-II and serum HBV DNA levels.

CONCLUSIONS

PIVKA-II was more efficient than AFP for the diagnosis of early HCC and has no correlation with serum HBV DNA levels.

Serum biomarkers and risk of hepatocellular carcinoma recurrence after liver transplantation

Liver transplantation (LT) is the only potentially curative treatment for selected patients with cirrhosis and hepatocellular carcinoma (HCC) who are not candidates for resection. When the Milan criteria are strictly applied, 75% to 85%of 3- to 4-year actuarial survival rates are achieved, but up to 20% of the patients experience HCC recurrence after transplantation. The Milan criteria are based on the preoperative tumor macromorphology, tumor size and number on computed tomography or magnetic resonance imaging that neither correlate well with posttransplant histological study of the liver explant nor accurately predict HCC recurrence after LT, since they do not include objective measures of tumor biology. Preoperative biological markers, including alpha-fetoprotein, des-gamma-carboxiprothrombin or neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio, can predict the risk for HCC recurrence after transplantation. These biomarkers have been proposed as surrogate markers of tumor differentiation and vascular invasion, with varied risk magnitudes depending on the defined cutoffs. Different studies have shown that the combination of one or several biomarkers integrated into prognostic models predict the risk of HCC recurrence after LT more accurately than Milan criteria alone. In this review, we focus on the potential utility of these serum biological markers to improve the performance of Milan criteria to identify patients at high risk of tumoral recurrence after LT.

Prognostic value of PIVKA-II in hepatocellular carcinoma patients receiving curative ablation: A systematic review and meta-analysis

BACKGROUND

Several studies have been conducted to evaluate the prognostic value of prothrombin induced by vitamin K absence-II (PIVKA-II) overexpression in hepatocellular carcinoma patients treated with curative ablation. However, the results remain controversial. The purpose of this meta-analysis was to explore the correlation between PIVKA-II expression and survival outcomes in these patients.

METHODS

We performed a systematic literature search in PubMed, EMBASE, Medline, Cochrane Library, and Web of Science to identify the relevant articles investigating the prognostic value of PIVKA-II in patients with hepatocellular carcinoma. Combined hazard ratios (HR) and their 95% confidence intervals (CI) for overall survival and recurrence-free survival were calculated as the analysis endpoints.

RESULTS

A total of 15 cohorts encompassing 5647 patients were included. The results indicated that elevated PIVKA-II was significantly associated with poorer overall survival (HR 1.59; 95% CI 1.40, 1.82; P < 0.001) and recurrence-free survival (HR 1.76; 95% CI 1.42, 2.17; P < 0.001). Similar results were observed in the subgroup analysis based on sample size, analytical method, treatment modality, and cut-off value.

CONCLUSIONS

This meta-analysis suggests that elevated PIVKA-II is a predictor of unfavorable overall survival and recurrence-free survival in hepatocellular carcinoma patients receiving curative ablation. More rigorous studies are warranted to confirm the clinical utility of PIVKA-II in determining hepatocellular carcinoma prognosis.

Des-gamma-carboxy prothrombin antagonizes the effects of Sorafenib on human hepatocellular carcinoma through activation of the Raf/MEK/ERK and PI3K/Akt/mTOR signaling pathways

Despite significant progress, advanced hepatocellular carcinoma (HCC) remains an incurable disease, and the overall efficacy of targeted therapy by Sorafenib remains moderate. We hypothesized that DCP (des-gamma-carboxy prothrombin), a prothrombin precursor produced in HCC, might be one of the reasons linked to the low efficacy of Sorafenib. We evaluated the efficacy of Sorafenib in HLE and SK-Hep cells, both of which are known DCP-negative HCC cell lines. In the absence of DCP, Sorafenib effectively inhibited the growth of HCC and induced cancer cell apoptosis. In the presence of DCP, HCC was resistant to Sorafenib-induced inhibition and apoptosis, as determined by in vitro assays and in mice xenografted with HLE cells. Molecular analysis of HLE xenografted-nude mice showed that DCP activates the transduction of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR cascades. DCP might stimulate the formation of compensatory feedback loops in the intricately connected signaling pathways when kinases are targeted by Sorafenib. Our results indicate that DCP antagonizes the inhibitory effects of Sorafenib on HCC through activation of the Ras/Raf/MEK/ERK and Ras/PI3K/Akt/mTOR signaling pathways. Taken together, our findings define a DCP-mediated mechanism of inhibition of Sorafenib in HCC, which is critical for targeting therapy in advanced HCC.

Diagnostic value of prothrombin induced by the absence of vitamin K or antagonist-II (PIVKA-II) for early stage HBV related hepatocellular carcinoma

BACKGROUND

To evaluate the diagnostic efficacy of prothrombin induced by the absence of vitamin K or antagonist-II (PIVKA-II) for early stage hepatitis virus B (HBV) related hepatocellular carcinoma (HCC).

METHODS

Serums levels of PIVKA-II and a-Fetoprotein (AFP) was detected and compared in 113 patients with clinical confirmed Barcelona Clinic Liver Cancer (BCLC) stage 0-A HBV-related HCC and 161 chronic hepatitis B (CHB) patients. Diagnostic efficiencies as well as cut-off values of PIVKA-II, AFP and combination of the two markers were calculated using receiver operator curve (ROC) analysis.

RESULTS

The mean level of PIVKA-II among HCC patients were 79.64 ± 149.88, significantly higher than control group (P < 0.001). ROC results showed that among those AFP-negative HCC patients, the area under ROC curve (AUROC) of PIVKA-II was 0.73 (95%CI 0.640-0.815, P < 0.001). Among HCC patients diagnosed with small HCC (tumor size ≤2 cm), the AUROC of PIVKA- II was 0.692 (95%CI 0.597-0.788, P < 0.001). To evaluate the diagnostic value of PIVKA-II in HCC patient, all CHB cases were pooled together as control for analysis. The AUROC of PIVKA-II was 0.756 (95%CI 0.698-0.814, P < 0.001), and the optimal cutoff value of PIVKA-II was 32.09 mAU/ml with sensitivity of 52.21% and specificity of 81.49%. When serum levels of PIVKA-II and AFP were combined to obtain a new marker for HCC diagnosis, PIVKA-II + AFP further increased diagnostic efficiency, with AUROC of 0.868 (95%CI 0.822-0.913), higher than that of AFP (P < 0.01) or PIVKA-II (P < 0.001) alone. In addition, we found that HCC patients in poorly differentiated- undifferentiated group and in microvascular invasion group had higher levels of PIVKA-II. Multivariate analysis showed that high serum PIVKA-II level (OR = 1.003, 95%CI 1.001-1.007, P = 0.047) was an independent risk factor for microvascular invasion in HCC patients.

CONCLUSION

Serum PIVKA-II level is a potential marker for early diagnosis of HCC and microvascular invasion. The use of PIVKA-II may improve assessment of tumor prognosis and guide development of therapeutic strategy.

Clinical Impact of Vitamin K Dosing on Sorafenib Treatment for Hepatocellular Carcinoma

Background: Some researchers have suggested that vitamin K enhances the antitumor effect of sorafenib for hepatocellular carcinoma (HCC) in vitro and in vivo. In this study, we examined the clinical impact of vitamin K dosing for sorafenib treatment. Methods: Twenty-nine out of 65 patients treated with sorafenib for HCC were simultaneously dosed with vitamin K. We retrospectively investigated progression-free survival (PFS) and overall survival (OS) in the vitamin K-dosed group and sorafenib alone group. We also examined the changes in serum des-γ-carboxy prothrombin (DCP) levels, which vitamin K is involved with. Results: The median PFS was prolonged in the sorafenib + vitamin K group compared with the sorafenib alone group (6.0 months and 2.0 months, respectively; P<0.001, hazard ratio〔HR〕: 0.25). The median OS was also significantly extended (12.5 months vs. 10.0 months; P=0.009, HR: 0.47). Despite suppressed tumor growth, serum DCP levels had increased in cases of disease-controlled patients in the sorafenib alone group 8 weeks after the beginning of treatment, (2.28±0.91 to 2.64±1.03, P= 0.048). In contrast, the serum DCP levels of the sorafenib + vitamin K group had declined both in patients with controlled disease and in patients with progressive disease (1.97±0.57 to 1.29±0.28, P=0.002 and 2.90±1.32 to 1.78±0.53, P=0.034, respectively). Conclusions: To the best of our knowledge, this is the first clinical report showing enhanced antitumor action of sorafenib by vitamin K. Our clinical findings suggest that vitamin K may have the synergistic effect by suppressing production of DCP, a tumor growth and angiogenesis factor.

Roles and Signaling Pathways of Des-γ-Carboxyprothrombin in the Progression of Hepatocellular Carcinoma

Des-γ-carboxyprothrombin (DCP), an abnormal prothrombin produced in human hepatocellular carcinoma (HCC), plays crucial roles in the progression of HCC. DCP binding to cellular mesenchymal-epithelial transition factor (c-Met) is an initial event and consequently stimulates HCC through the increase of c-Met-Janus kinase 1- signal transducers and activators of transcription pathways. DCP stimulates HCC invasion through activation of matrix metalloproteinase via upregulation of extracellular signal-regulated kinase-mitogen-activated protein kinase (MAPK) pathway. DCP stimulates HCC angiogenesis through activation of the DCP-kinase insert domain receptor-phospholipaseC-γ-MAPK pathway. Identification of these pathways is important for designing the therapeutic strategy for HCC.

Post-ablation des-gamma-carboxy prothrombin level predicts prognosis in hepatitis B-related hepatocellular carcinoma

BACKGROUND & AIMS

We investigated whether pre- or post-ablation serum alpha-foetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) levels can predict prognosis in patients with curative radiofrequency ablation (RFA) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

METHODS

We retrospectively analysed 412 patients with HBV-related single HCC treated with percutaneous RFA between January 2004 and December 2013. AFP and DCP levels were measured before (pre-ablation) and 1 month after treatment (post-ablation). We assessed predictive factors for overall and recurrence-free survival.

RESULTS

On univariate analysis, Child-Pugh score, Model for End-Stage Liver Disease (MELD) score, platelet count, tumour size, Barcelona Clinic Liver Cancer (BCLC) stage, and pre- and post-ablation DCP were significant for overall survival; and age, Child-Pugh score, MELD score, platelet count, tumour size, Cancer of the Liver Italian Program (CLIP) score, BCLC stage, and pre- and post-ablation AFP and DCP were significant for recurrence-free survival. Multivariate analysis revealed significant differences in overall survival by MELD score and tumour size and in recurrence-free survival by BCLC stage. Among the tumour markers, post-ablation DCP was an independent prognostic factor for overall and recurrence-free survival [hazard ratio (HR), 3.438; 95% confidence interval (CI), 1.331-8.877; P = 0.011 and HR, 4.934; 95% CI, 2.761-8.816; P < 0.001 respectively]. Post-ablation AFP was associated with recurrence-free survival (HR, 1.995; 95% CI, 1.476-2.697; P < 0.001) but not overall survival.

CONCLUSIONS

In patients with HBV-related HCC, post-ablation serum DCP is a useful biomarker for predicting survival and recurrence after curative RFA.

Prediction of hepatocellular carcinoma biological behavior in patient selection for liver transplantation

Morphological criteria have always been considered the benchmark for selecting hepatocellular carcinoma (HCC) patients for liver transplantation (LT). These criteria, which are often inappropriate to express the tumor’s biological behavior and aggressiveness, offer only a static view of the disease burden and are frequently unable to correctly stratify the tumor recurrence risk after LT. Alpha-fetoprotein (AFP) and its progression as well as AFP-mRNA, AFP-L3%, des-γ-carboxyprothrombin, inflammatory markers and other serological tests appear to be correlated with post-transplant outcomes. Several other markers for patient selection including functional imaging studies such as ¹⁸F-FDG-PET imaging, histological evaluation of tumor grade, tissue-specific biomarkers, and molecular signatures have been outlined in the literature. HCC growth rate and response to pre-transplant therapies can further contribute to the transplant evaluation process of HCC patients. While AFP, its progression, and HCC response to pre-transplant therapy have already been used as a part of an integrated prognostic model for selecting patients, the utility of other markers in the transplant setting is still under investigation. This article intends to review the data in the literature concerning predictors that could be included in an integrated LT selection model and to evaluate the importance of biological aggressiveness in the evaluation process of these patients.

Performance of PIVKA-II for early hepatocellular carcinoma diagnosis and prediction of microvascular invasion

BACKGROUND & AIMS

Prothrombin induced by vitamin K absence-II (PIVKA-II) is a diagnostic and surveillance marker for HCC mainly used in Asia, and has also been shown to be a predictor of microvascular invasion (MVI), a major prognostic factor in HCC. However, experience with PIVKA-II in Europe remains limited.

METHODS

In a French cohort, we conducted a case-control study to compare the performances of α-fetoprotein (AFP) and PIVKA-II serum levels for diagnosis of early stage HCC, and we determined the value of PIVKA-II serum and tissue expression in pre-operative detection of MVI. 43 cirrhotic control patients and 85 HCC cases were included, of which 54 (63.5%) had early stage HCC (n=22 very early, n=32 early). PIVKA-II tissue expression was assessed by immunohistochemistry in HCC surgical samples.

RESULTS

For the diagnosis of early HCC, PIVKA-II had a sensitivity of 77% and a specificity of 82% at a cut-off of 42 mAU/ml, vs. 61% and 50% for AFP at a cut-off of 5.5 ng/ml (AUC 0.81 vs. 0.58, respectively). A PIVKA-II level >90 mAU/ml was an independent predictor of MVI (HR 3.5; 95% CI 1.08-11.8; p=0.043). High PIVKA-II tissue expression was significantly associated with the presence of MVI (p=0.001). When combining PIVKA-II immunostaining with the PIVKA-II serum level, sensitivity and specificity for the diagnosis of MVI increased from 70% to 87% and 63% to 90%, respectively.

CONCLUSIONS

PIVKA-II was more efficient than AFP for the diagnosis of early HCC, and could be used as a predictive biomarker of MVI.

Prognostic values of vascular endothelial growth factor and matrix metalloproteinase-2 in hepatocellular carcinoma after radiotherapy

OBJECTIVES

Hepatocellular carcinoma (HCC) is a highly vascularized tumor. In this study, we investigated the prognostic and predictive values of proangiogenic factors in HCC patients receiving radiotherapy.

METHODS

Between September 2008 and December 2009, a total of 50 patients treated with radiotherapy were prospectively enrolled in this study. Serum and urine samples were collected <1 week before and after radiotherapy.

RESULTS

After completion of radiotherapy, serum vascular endothelial growth factor (VEGF)/platelet (Plt) levels were significantly increased (p < 0.01). Patients who experienced hepatic tumor recurrence outside the radiation field showed higher VEGF-A/Plt levels before and after radiotherapy than patients who did not (p = 0.04), whereas patients who had hepatic tumor recurrence inside the radiation field showed significantly higher matrix metalloproteinase (MMP)-2 levels after radiotherapy (p = 0.04). On multivariate analyses, a high level of either VEGF/Plt or MMP-2 (≥median) before radiotherapy was a significant independent prognostic factor for a worse progression-free survival (p = 0.04).

CONCLUSIONS

In HCC patients receiving radiotherapy, levels of VEGF/Plt and MMP-2 before radiotherapy can be useful to predict treatment outcome. This study also suggests the necessity of anti-angiogenic therapy, such as sorafenib, since radiotherapy increases VEGF/Plt levels, and higher levels of VEGF/Plt are associated with a poor outcome.

Hepatocellualar carcinoma serum markers

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world. In most cases, HCC is diagnosed at a late stage. Therefore, the prognosis of patients with HCC is generally poor. The recommended screening strategy for patients with cirrhosis includes the determination of serum α-fetoprotein (AFP) levels and an abdominal ultrasound every 6 months to detect HCC at an earlier stage. AFP, however, is a marker characterized by poor sensitivity and specificity, and abdominal ultrasound is highly dependent on the operator's experience. In addition to AFP, Lens culinaris agglutinin-reactive AFP (AFP-L3), des-γ-carboxy prothrombin (DCP), glypican-3 (GPC-3), osteopontin (OPN), and several other biomarkers (such as squamous cell carcinoma antigen-immunoglobulin M complexes [SCCA-IgM], alpha-1-fucosidase [AFU], chromogranin A [CgA], human hepatocyte growth factor, insulin-like growth factor) have been proposed as markers for the early detection of HCC. For these markers, we describe the mechanisms of production, and their diagnostic and prognosis roles. None of them is optimal; however, when used together, their sensitivity in detecting HCC is increased. Recent research has shown that some biomarkers have mitogenic and migratory activities in the angiogenesis of HCC and are a factor of tumor growth.

Des-γ-carboxyl prothrombin is associated with tumor angiogenesis in hepatocellular carcinoma

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) is a hypervascular tumor, and angiogenesis plays an important role in its development. Previously, we demonstrated that des-γ-carboxyl prothrombin (DCP) promotes both cell proliferation and migration of human umbilical vein endothelial cells (HUVECs) by inducing the autophosphorylation of kinase insert domain receptor (KDR). In the present study, DCP-associated tumor angiogenesis was assessed by comparing hypovascular and common hypervascular HCC.

METHODS

The solitary HCCs of 827 patients were classified into two groups according to the tumor density at the arterial phase of a dynamic computed tomography scan; the initial clinical data of patients with the hyper- and hypovascular types were compared. The HCC tissues from 95 tumors were analyzed by immunohistochemical staining for DCP and phosphorylated KDR, and intratumoral microvessel density (MVD) was analyzed to evaluate microvessel angiogenesis.

RESULTS

The serum DCP levels (320 ± 3532 mAU/mL) and tumor size (18.4 ± 9.0 mm) of patients with hypervascular HCC were significantly greater than those with hypovascular HCC (38.7 ± 80 mAU/mL and 14.6 ± 5.2 mm, P < 0.001). Immunohistochemical analysis revealed that the expressions of DCP and phospho-KDR were significantly greater in hypervascular HCC (71.4% and 31.0%, respectively) than in hypovascular HCC (7.6% and 5.7%, respectively). Intratumoral MVD was significantly correlated with DCP (r = 0.48, P < 0.0001).

CONCLUSIONS

des-γ-carboxyl prothrombin production is associated with tumor angiogenesis in HCC.

Inhibition of intestinal adenoma formation in APC(Min/+) mice by Riccardin D, a natural product derived from liverwort plant Dumortiera hirsuta

BACKGROUND

Mutation of tumor suppressor gene, adenomatous polyposis coli (APC), is the primary molecular event in the development of most intestinal carcinomas. Animal model with APC gene mutation is an effective tool for study of preventive approaches against intestinal carcinomas. We aimed to evaluate the effect of Riccardin D, a macrocyclic bisbibenzyl compound, as a chemopreventive agent against intestinal adenoma formation in APC(Min/+) mice.

METHODS

APC(Min/+) mice were given Riccardin D by p.o. gavage for 7 weeks. Mice were sacrificed, and the number, size and histopathology of intestinal polyps were examined under a microscope. We performed immunohistochemical staining, western blotting, reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) in intestinal polyps to investigate the mechanism of chemopreventive effect of Riccardin D.

RESULTS

Riccardin D treatment resulted in a significant inhibition of intestinal adenoma formation, showing a reduction of polyp number by 41.7%, 31.1% and 44.4%, respectively, in proximal, middle and distal portions of small intestine. The activity of Riccardin D against polyp formation was more profound in colon, wherein Riccardin D decreased polyp number by 79.3%. Size distribution analysis revealed a significant reduction in large-size polyps (2-3 mm) by 40.0%, 42.5% and 33.3%, respectively, in proximal, middle and distal portions of small intestine, and 77.8% in colon. Histopathological analysis of the intestinal polyps revealed mostly hyperplastic morphology without obvious dysplasia in Riccardin D-treated mice. Molecular analyses of the polyps suggested that the inhibitory effect of Riccardin D on intestinal adenoma formation was associated with its abilities of reduction in cell proliferation, induction of apoptosis, antiangiogenesis, inhibition of the Wnt signaling pathway and suppression of inflammatory mediators in polyps.

CONCLUSIONS

Our results suggested that Riccardin D exerts its chemopreventive effect against intestinal adenoma formation through multiple mechanisms including anti-proliferative, apoptotic, anti-angiogenic and anti-inflammatory activity.

Targeting c-Met as a promising strategy for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a severe condition that is found worldwide. Liver transplantation, surgical resection, and local-regional therapy such as transarterial chemoembolization have made great progress and play a dominant role in HCC management. However, the high frequency of tumor recurrence and/or metastasis after those treatments acquires systematic drug intervention. The approval of sorafenib, an agent that targets receptor tyrosine kinases (RTKs), as the first effective drug for systemic treatment of HCC represents a milestone in treatment of this disease. As a typical member of the RTK family, c-Met represents an intriguing target for cancer therapy. However, the role of the c-Met signal transduction pathway is less unambiguous in HCC pathology, giving rise to concerns about the feasibility of utilizing c-Met targeting approaches for HCC treatment. Recently, studies on des-γ-carboxy prothrombin, an abnormal cytokine secreted by HCC cells, by the current authors and other researchers have highlighted the critical role of c-Met signaling in HCC progression. This review takes a second look at the c-Met signal transduction pathway and discusses the possibility of targeting c-Met as a therapeutic strategy for HCC treatment.

Effect of c-Met inhibitor SU11274 on hepatocellular carcinoma cell growth

c-Met, a type of receptor tyrosine kinase, may be significantly associated with the progression of hepatocellular carcinoma (HCC). In addition, des-γ-carboxyprothrombin (DCP) has been found to interact with c-Met and activate HCC cell growth. Therefore, the functional inhibition of c-Met expressed on HCC cells should arrest HCC cell growth. The present study found that the c-Met inhibitor SU11274 suppressed HCC cell growth by inhibiting the activation of c-Met. Furthermore, this inhibitor also neutralized the activation of HCC cell growth resulting from the addition of DCP. These results suggest that the functional inhibition of c-Met might be a target for the development of chemotherapeutic agents for HCC, and especially those that are positive for expression of DCP.

LYP, a bestatin dimethylaminoethyl ester, inhibited cancer angiogenesis both in vitro and in vivo

Our previous study revealed that LYP, a bestatin dimethylaminoethyl ester, inhibited the growth of human ovarian carcinoma ES-2 xenografts in mice and suppressed aminopeptidase N (APN/CD13) activity more potently than bestatin. In this study, we examined the inhibitory effect of LYP on migration and formation of capillary tube of human umbilical vascular endothelial cells (HUVECs) in vitro and anti-angiogenesis in ES-2 xenografts in mice. LYP did not possess cytotoxicity to HUVEC proliferation according to the MTT assay and trypan blue exclusion assay. However, APN/CD13 activity on cell surface of HUVECs was suppressed in the presence of LYP as measured by quantifying the enzymatic cleavage of the substrate l-leucine-p-nitroanilide. The assays of scratch and transwell chamber showed that LYP significantly inhibited HUVEC migration and invasion through Matrigel coated polycarbonate filters. Capillary tube formation assay revealed that the number of branch points formed by HUVECs on 3-D Matrigel was reduced after incubation with LYP. The anti-angiogenesis of LYP was verified in ES-2 xenografts in mice. The mean vascular density (MVD) and mean vascular luminal diameter (MVLD) were markedly reduced by LYP after two weeks of intravenous injection as evaluated by CD34 immunohistochemical staining. LYP suppression of cancer angiogenesis was greater than that of bestatin. The inhibition of angiogenic molecules may involve in anti-angiogenesis of LYP. The levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and transforming growth factor-alpha (TGF-α) were decreased in HUVECs and ES-2 xenografts after treatment with LYP as determined by Western blot analysis. These results indicated that the high efficacy of LYP may partially relate to the inhibition of angiogenesis.

Des-γ-carboxyl prothrombin induces matrix metalloproteinase activity in hepatocellular carcinoma cells by involving the ERK1/2 MAPK signalling pathway

Des-γ-carboxy prothrombin (DCP), an aberrant prothrombin produced by hepatocellular carcinoma (HCC) cells, has been shown to be associated with the biological malignant potential of HCC. The aim of this study was to evaluate the effect of DCP on HCC cell growth and metastasis, and to explore the underlying molecular mechanisms. DCP significantly stimulated HCC cell growth, as measured by cell counting kit-8 assay. Transwell chamber assay showed that DCP increased HCC cell migration through reconstituted extracellular matrix (Matrigel). Gelatin zymography assay and Western blot analysis demonstrated that DCP increased the secretion and expression of matrix metalloproteinase (MMP)-2 and MMP-9 in the supernatant of cultured HCC cells and on tumour cell membranes. DCP was found to bind to the cell surface receptor Met, resulting in Met phosphorylation and subsequent activation of the epidermal growth factor receptor (EGFR). Western blot analysis demonstrated that DCP stimulated a sequential kinase phosphorylation cascade including ERK1/2, MEK1/2 and c-Raf, indicating activation of the extracellular signal-regulated kinase/mitogen activated protein kinase (ERK1/2 MAPK) signalling pathway. Furthermore, blocking ERK1/2 MAPK activation with ERK1/2 inhibitor PD98059 essentially abolished the DCP-induced MMP-2 and MMP-9 activity, confirming the signalling pathway of DCP stimulation. Taken together, these results suggested that DCP stimulates HCC growth and promotes HCC metastasis by increasing the activity of MMP-2 and MMP-9 through activation of the ERK1/2 MAPK signalling pathway.

Clinical and molecular insights into the hepatocellular carcinoma tumour marker des-γ-carboxyprothrombin

Des-γ-carboxyprothrombin (DCP) is known as a tumour marker for hepatocellular carcinoma (HCC). Various tumour markers have been developed for serological diagnosis of cancers, including HCC, in order to increase the survival rate of cancer patients. The currently recommended combined testing of DCP and α-fetoprotein (AFP) or Lens culinaris agglutinin-reactive fraction of α-fetoprotein has been established to diagnose HCC. This combined testing using several tumour markers helps to increase the sensitivity of diagnosis of HCC, thus significantly increasing the clinical usefulness of DCP. The excessive production of DCP may be related to worse tumour behaviour, such as the presence of vascular invasion and intrahepatic metastasis of HCC cells. A high level of DCP was suggested to be useful as one of the factors in new recipient selection criteria of liver transplantation. The clinical use of DCP, therefore, might play a vital role in predicting tumour behaviour in patients with HCC. That said, the basic mechanism of DCP production has not been fully clarified. Various factors such as vitamin K(2) and γ-glutamyl carboxylase may contribute to the production of DCP and have a complex relationship. Moreover, recent studies have revealed that DCP functions as a growth factor and might play significant roles in cancer progression. Thus, DCP represents a potential target of drug discovery to establish new chemotherapeutic strategy for HCC. However, various issues have to be resolved to construct a novel therapy for HCC-targeting DCP. Innovation is required to make further progress in examining DCP.

Expression of KL-6 mucin, a human MUC1 mucin, in intrahepatic cholangiocarcinoma and its potential involvement in tumor cell adhesion and invasion

AIMS

Aberrant expressions of KL-6 mucin were proved to be associated with worse tumor behaviors of many carcinomas. This study was to evaluate the expression KL-6 mucin, a human MUC1 mucin, in intrahepatic cholangiocarcinoma (CC) and its significance in tumor progression.

MAIN METHODS

KL-6 mucin expressions in 21 patients with CC, 12 with combined hepatocellular and cholangiocarcinoma (cHCC-CC), and 78 with hepatocellular carcinoma (HCC) were detected by immunohistochemical staining. The effects of two glycosylation inhibitors (tunicamycin and benzyl-alpha-N-acetylgalactosamine (BAG)) on CC cell proliferations were assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assays. KL-6 mucin expressions were detected by immunocytochemical staining and western blotting after tunicamycin or BAG treatment. Cell adhesive and invasive properties were evaluated by adhesion tests and transwell chamber assays after tunicamycin or BAG treatment.

KEY FINDINGS

Positive KL-6 mucin staining was observed in all CC tissues and CC areas of cHCC-CC tissues. Immunocytochemical staining and western blotting showed that KL-6 mucin expressions were significantly reduced after both inhibitors treatment. Cell adhesive properties were significantly decreased after both inhibitors treatment, while cell invasive abilities were significantly decreased after BAG but not tunicamycin treatment.

SIGNIFICANCE

This study indicated that KL-6 mucin might be a specific tumor target for CC. Therapeutic strategies that target glycosylation of KL-6 mucin may be useful to control aggressive behaviors of CC.

Des-gamma-carboxy prothrombin stimulates human vascular endothelial cell growth and migration

Des-gamma-carboxy prothrombin (DCP) is an aberrant prothrombin produced by hepatocellular carcinoma (HCC) cells. Serum and tissue DCP expressions are thought to reflect the biological malignant potential of HCC. However, the role of DCP in the development of angiogenesis is not well understood. Herein, we report the effects of DCP on growth and migration of human vascular endothelial cells. DCP significantly stimulated the proliferation of HUVEC (ECV304) cells in a dose and time dependent manner, as measured by the MTT assay. A continuous rapid migration of ECV304 cells was observed in the presence of DCP measured by the scratch wound assay. The continuous rapid invasive activity, measured by transwell chamber assay also showed that DCP increased endothelial cells migration through the reconstituted extracellular matrix (Matrigel). Further, the tube formation of vascular endothelial cells on 3-D Matrigel showed an increased number of branch points of ECV304 cells induced by DCP in a dose dependent manner. The levels of vascular endothelial cell growth-related angiogenic factors and matrix metalloproteinase were also examined. DCP significantly stimulated the expression levels of epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and matrix metalloproteinase (MMP)-2 (latent and active). Together, these data suggest that DCP is a novel type of vascular endothelial growth factor that possesses potent mitogenic and migrative activities in angiogenesis of HCC.