Circulating tumor cells measurements in hepatocellular carcinoma

Liquid biopsy in chronic liver disease

Chronic liver diseases account for a considerable toll of incapacities, suffering, deaths, and resources of the nation's health systems. They can be prevented, treated or even cured when the diagnosis is made on time. Traditional liver biopsy remains the gold standard to diagnose liver diseases, but it has several limitations. Liquid biopsy is emerging as a superior alternative to surgical biopsy given that it surpasses the limitations: it is more convenient, readily and repeatedly accessible, safe, cheap, and provides a more detailed molecular and cellular representation of the individual patient's disease. Progress in understanding the molecular and cellular bases of diseased tissues and organs that normally release cells and cellular components into the bloodstream is catapulting liquid biopsy as a source of biomarkers for diagnosis, prognosis, and prediction of therapeutic response, thus supporting the realization of the promises of precision medicine. The review aims to summarize the evidence of the usefulness of liquid biopsy in liver diseases, including the presence of different biomarkers as circulating epithelial cells, cell-free nucleic acids, specific species of DNA and RNA, and the content of extracellular vesicles.

Early dynamic changes in circulating tumor cells and prognostic relevance following interventional radiological treatments in patients with hepatocellular carcinoma

The aim of this study was to investigate the dynamic changes of circulating tumor cells (CTCs) in patients with hepatocellular carcinoma (HCC) before and immediately after conducting a microwave ablation (MWA) and conventional transarterial chemoembolization (C-TACE). Additionally, the CTCs short-term dynamics were compared with the clinical course of the HCC-patients. Blood samples from 17 patients with HCC who underwent MWA (n = 10) or C-TACE (n = 7) were analyzed. Venous blood was taken before and immediately after the radiological interventions to isolate and quantify CTCs using flow cytometry. CTCs were identified as CD45- and positive for the markers ASGPR, CD146 and CD274 (PD-L1). Patients were followed of up to 2.2 years after the radiological intervention. CTCs were detected in 13 HCC patients (76%) prior to the radiological interventions. The rate of CTCs was significantly decreased after the intervention in patients treated with MWA (0.4 CTCs/mL of blood, p = 0.031). However, no significant differences were observed in patients who received C-TACE (0.3 CTCs/mL of blood, p = 0.300). Overall, no correlation was found between the CTCs rate before and after the radiological intervention and recurrence rate of HCC. This preliminary data could confirm the tumoricidal effects of MWA in patients with HCC by significantly decreasing CTCs rate. In our study, we were able to detect CTCs in HCC patients using 3 different tumor markers. This preliminary data shows significant lower CTCs detected in response to MWA. However, large-scale randomized clinical trials are needed to determine the future role and the prognostic relevance of CTCs following this treatment.

Impact of Bridging Locoregional Therapies for Hepatocellular Carcinoma on Post-transplant Clinical Outcome

Long waiting times due to ongoing organ shortage have led to increased utilization of locoregional therapies (LRTs) to bridge patients with hepatocellular carcinoma (HCC) to liver transplantation (LT). We performed this study to evaluate the impact of LRTs on post-LT outcomes. We conducted a retrospective study of patients who were transplanted for HCC at Stanford University Hospital between 2008 and 2018 (n = 302). We found that receipt of ≥5 LRTs was an independent and significant predictor of poor overall 5-year survival (58.3% vs. 83.3%; HR 2.26, p = .03), poor recurrence-free 5-year survival (51.9% vs. 80.4%; HR 2.12, p = .03), and was associated with higher rates of recurrence (25.0% vs. 7.4%, p = .001). Moreover, recurrent HCC was more likely to be the cause of death (58.3% vs. 41.7%, p = .04) in patients who received ≥5 LRTs. Also, patients who required ≥5 LRTs showed an overall lower rate of radiological complete response (46.9% vs. 97.8%, p = .001) and were more likely to have more advanced pathological stage tumors in the explant (65.6% vs. 29.6%, p < .001). In conclusion, receipt of ≥5 bridging LRTs prior to LT is associated with worse post-transplant clinical outcomes.

Biomarkers for hepatocellular cancer

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. If diagnosed early, curative treatment options such as surgical resection, loco-regional therapies, and liver transplantation are available to patients, increasing their chances of survival and improving their quality of life. Unfortunately, most patients are diagnosed with late stage HCC where only palliative treatment is available. Therefore, biomarkers which could detect HCC early with a high degree of sensitivity and specificity, may play a crucial role in the diagnosis and management of the disease. This review will aim to provide an overview of the different biomarkers of HCC comprising those used in the diagnosis of HCC in at risk populations, as well as others with potential for prognosis, risk predisposition and prediction of response to therapeutic intervention.

Mitotic quiescence in hepatic cancer stem cells: An incognito mode

Hepatocellular carcinoma represents one of the most aggressive cancers with high recurrence rates. The high recurrence is a major problem in the management of this disease. Cancer stem cells (CSCs) are often regarded as the basis of cancer recurrence. The anti-proliferative therapy kills the proliferating cells but induces mitotic quiescence in CSCs which remain as residual dormant CSCs. Later on, withdrawal of treatment reactivates the residual CSCs from dormancy to produce new cancer cells. The proliferation of these newly formed cancer cells initiates new tumor formation in the liver leading to tumor recurrence. HCC cells evade the immune surveillance via modulating the key immune cells by alpha feto-protein (AFP) secreted from CSCs or hepatic progenitor cells. This AFP mediated immune evasion assists in establishing new tumors by cancer cells in the liver. In this review, we will summarise the CSC mechanisms of recurrence, mitotic quiescence, dormancy and reactivation of CSCs, metastasis and immune evasion of hepatocellular carcinoma.

Circulating tumor cells undergoing EMT are poorly correlated with clinical stages or predictive of recurrence in hepatocellular carcinoma

Experimental and clinical studies have highlighted that circulating tumor cell (CTC) with phenotypic hallmarks of epithelial-mesenchymal transition (EMT) plays a critical role in the metastatic and recurrence of solid malignancy. Here we retrospectively evaluated the presence of CTC and its EMT phenotypes in hepatocellular carcinoma (HCC) patients and investigated their clinical relevance. We optimized the Canpatrol^TM CTC analysis system to enumerate CTC and classify EMT phenotypes in 113 HCC patients before curative treatment and 143 HCC patients after curative treatment. The relationships between CTC and clinical characteristics were statistically analyzed. None of total CTC or its EMT phenotypes in HCC patients was correlated with clinical characteristics, such as age, sex, HBsAg, Child-Pugh score, liver cirrhosis, AFP, number of tumors, tumor size, vascular invasion and BCLC stage. Neither the level of total CTC nor its EMT phenotypes in HCC patients before or after curative treatment were predictive of recurrence. Additionally, dynamic changes of CTC and its EMT phenotypes were not relevant to HCC recurrence after curative treatment in our study. Wefound CTC count and EMT classification were not correlated with clinical stages or predictive of HCC recurrence, but further large, multicenter studies are needed to confirm these results.

Aptamer-Based Sandwich Assay for Measurement of Thymidine Kinase 1 in Serum of Cancerous Patients

Thymidine kinase 1 (TK1) is traditionally a serum biomarker that is elevated in the early stages of malignancies. The diagnostic and prognostic role of TK1 for screening and monitoring human malignancies has recently been investigated. Anti-human TK1 aptamers were selected through 12 iterative rounds of systematic evolution of ligands by exponential enrichment from a DNA library. The aptamer pool of round 12 was amplified, and the polymerase chain reaction product was cloned on the TA vector. Of the 85 colonies obtained, 52 were identified as positive clones. These aptamers were screened for TK1 with surface plasmon resonance, where apta37 and apta69 showed the highest affinity for TK1. The TK1_apta37 and TK1_apta69 aptamers were used in a sandwich assay platform and successfully detected TK1 in the concentration range of 54-3500 pg mL^-1. Clinical samples from 60 cancerous patients were also tested with this assay system and compared using the conventional antibody-based enzyme-linked immunosorbent assay kit. The aptamer sandwich assay demonstrated a dynamic range for TK1 at clinically relevant serum levels, covering subpicogram per milliliter concentrations. The new approach offers a simple and robust method for detecting serum biomarkers that have low and moderate abundance. The results of this study demonstrate the screening capability of the aptamer sandwich assay platform and its potential applicability to the point-of-care testing system.

Golgi protein 73 and its diagnostic value in liver diseases

Golgi protein 73 (GP73, also referred to as Golph 2) with 400 amino acids is a 73 kDa transmembrane glycoprotein typically found in the cis-Golg complex. It is primarily expressed in epithelial cells, which has been found upregulated in hepatocytes in patients suffering from both viral and non-viral liver diseases. GP73 has drawn increasing attention for its potential application in the diagnosis of liver diseases such as hepatitis, liver cirrhosis and liver cancer. Herein, we reviewed the discovery history of GP73 and summarized studies by many groups around the world, aiming at understanding its structure, expression, function, detection methods and the relationship between GP73 and liver diseases in various settings.

Modulatory effect of luteolin on redox homeostasis and inflammatory cytokines in a mouse model of liver cancer

Liver cancer is one of the leading causes of cancer-associated mortality worldwide. Due to changes in lifestyle and daily exposure to various chemicals, which may lead to chemical intoxication, liver cancer has become a prominent disease in humans. Chemical-induced carcinogenesis in experimental animals has become a reliable model for the investigation of liver cancer-associated biological alterations that may mimic human hepatic cancer. Liver cancer in BALB/c mice was induced by administering diethylnitrosamine (DN) in drinking water for 6 weeks. Luteolin (LUT) is a flavone that is found in the leaves of the majority of spice-associated plants. In the present study, 20 µg/kg of body weight LUT was administered intraperitoneally every alternate day to treat the DN-induced liver cancer in mice. LUT improved the host system by modifying the levels of α-fetoprotein, enzymatic antioxidants, such as superoxide dismutase and catalase, marker enzymes, such as AST and ALT, and lipid peroxides in the plasma or liver tissue. LUT also reduced the levels of glutathione and the inflammatory cytokines interleukin-2 and interferon-γ in the plasma or liver tissue. These findings augmented the treatment against liver cancer and supported the effective anticancer activity of LUT against DN-induced liver carcinogenesis in mice.

Comparison of Two Types of Liquid Biopsies in Patients With Hepatocellular Carcinoma Awaiting Orthotopic Liver Transplantation

INTRODUCTION

Orthotopic liver transplantation (OLT) is considered one of the few curative treatments available for early stages of hepatocellular carcinoma (HCC). It has been shown that more than 10% of transplanted individuals suffer relapse during the first year after surgery and most of them die because of the tumor. The circulating tumor cells (CTCs) are the main source of recurrences as they disseminate from a primary or metastatic tumor lesion through peripheral blood. We aimed to determine the concentration of CTCs in peripheral blood in these patients by 2 different approaches: the CellSearch and the IsoFlux systems to assess their applicability to this disease monitoring.

PATIENTS AND METHODS

A comparative study was conducted in 21 patients with HCC eligible for liver transplantation according to the Milan criteria, whose peripheral blood was processed by the CellSearch and the IsoFlux systems.

RESULTS

CTCs were isolated in 1 of the 21 patients (4.7%) by the CellSearch system and in 19 of the 21 patients (90.5%) by the IsoFlux method. The comparison of both methods using Bland-Altman plot shows that there is not consistency in the determination of CTCs in our patients, finding a proportional bias between them.

CONCLUSION

The results obtained by both CTCs isolation systems are not interchangeable nor transferable. The CellSearch system does not seem to be the ideal approach for studying CTCs in patients with HCC. The IsoFlux system displays greater sensitivity in the identification of CTCs and might become an important tool in patient management.

Technological advances in precision medicine and drug development

New technologies are rapidly becoming available to expand the arsenal of tools accessible for precision medicine and to support the development of new therapeutics. Advances in liquid biopsies, which analyze cells, DNA, RNA, proteins, or vesicles isolated from the blood, have gained particular interest for their uses in acquiring information reflecting the biology of tumors and metastatic tissues. Through advancements in DNA sequencing that have merged unprecedented accuracy with affordable cost, personalized treatments based on genetic variations are becoming a real possibility. Extraordinary progress has been achieved in the development of biological therapies aimed to even further advance personalized treatments. We provide a summary of current and future applications of blood based liquid biopsies and how new technologies are utilized for the development of biological therapeutic treatments. We discuss current and future sequencing methods with an emphasis on how technological advances will support the progress in the field of precision medicine.

A New Cell Block Method for Multiple Immunohistochemical Analysis of Circulating Tumor Cells in Patients with Liver Cancer

PURPOSE

We developed a new method of detecting circulating tumor cells (CTCs) in liver cancer patients by constructing cell blocks from peripheral blood cells, including CTCs, followed by multiple immunohistochemical analysis.

MATERIALS AND METHODS

Cell blockswere constructed from the nucleated cell pellets of peripheral blood afterremoval of red blood cells. The blood cell blocks were obtained from 29 patients with liver cancer, and from healthy donor blood spikedwith seven cell lines. The cell blocks and corresponding tumor tissues were immunostained with antibodies to seven markers: cytokeratin (CK), epithelial cell adhesion molecule (EpCAM), epithelial membrane antigen (EMA), CK18, α-fetoprotein (AFP), Glypican 3, and HepPar1.

RESULTS

The average recovery rate of spiked SW620 cells from blood cell blocks was 91%. CTCs were detected in 14 out of 29 patients (48.3%); 11/23 hepatocellular carcinomas (HCC), 1/2 cholangiocarcinomas (CC), 1/1 combined HCC-CC, and 1/3 metastatic cancers. CTCs from 14 patients were positive for EpCAM (57.1%), EMA (42.9%), AFP (21.4%), CK18 (14.3%), Gypican3 and CK (7.1%, each), and HepPar1 (0%). Patients with HCC expressed EpCAM, EMA, CK18, and AFP in tissue and/or CTCs, whereas CK, HepPar1, and Glypican3 were expressed only in tissue. Only EMA was significantly associated with the expressions in CTC and tissue. CTC detection was associated with higher T stage and portal vein invasion in HCC patients.

CONCLUSION

This cell block method allows cytologic detection and multiple immunohistochemical analysis of CTCs. Our results show that tissue biomarkers of HCC may not be useful for the detection of CTC. EpCAM could be a candidate marker for CTCs in patients with HCC.

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.

Circulating Tumor Cells in Gastrointestinal Cancer: Current Practices and Future Directions

GI cancers are the leading cause of cancer-related death worldwide primarily due to a combination of late presentation and aggressive biology. The lack of adequate biomarkers for screening, diagnosis, staging, and prognosis confounds clinical decision-making and delays potentially effective therapies. Circulating tumor cells (CTCs) are a new biomarker with particular promise in GI cancers, potentially offering clinicians and researchers real-time access to tumor tissue in a reliable, safe, and cost-effective manner. Preliminary studies have investigated the potential clinical utility of CTCs for all GI cancer types with promising results. Furthermore, advances in single cell analytics have been successfully applied to CTCs, allowing for exciting new clinical and research applications. In this chapter, we will review the current state of CTC research in GI cancers as well as the potential future applications that are currently being developed.

The clinical role of 'liquid biopsy' in hepatocellular carcinoma

Circulating free tumor DNA (ctDNA) is DNA released from necrotic or apoptotic tumor cells into the bloodstream. Absolute levels of ctDNA, as well as genetic mutations and epigenetic changes detected in ctDNA are useful biomarkers of tumor biology, progression and response to therapy in many tumor types and recent evidence suggests they may be useful in hepatocellular carcinoma (HCC). ctDNA detected in blood, therefore, offers a minimally invasive, easily repeated 'liquid biopsy' of cancer, providing real-time dynamic analysis of tumor behavior and treatment response that could revolutionize both clinical and research practice in HCC. In this review, we provide a critical summary of the evidence for the utility of ctDNA as a diagnostic and prognostic biomarker in HCC.

Overexpression of OCT4 contributes to progression of hepatocellular carcinoma

The abnormal change of octamer transcription factor 4 (OCT4) is associated with tumor progression; however, its effect on hepatocellular carcinoma (HCC) behavior remains unclear. The purpose of this study was to determine the correlation between HCC and OCT4. In the present study, IHC, western blot analysis, and QRT-PCR were performed to identify differentially expressed OCT4 in a series of HCC tissues and adjacent non-cancerous tissues. In addition, the functions of OCT4 on HCC progression were studied in vitro. Silencing of OCT4 with siRNA was performed in HCC cell lines, and the impact on proliferation, migration, and the EMT marker of HCC was analyzed. Our results found that OCT4 levels were significantly higher in HCC tissues compared with the adjacent non-cancerous tissues. Furthermore, OCT4 siRNA significantly reduced the proliferation rate of SMMC-7721 and HepG2 cells, inhibited the migration and inversion, and could reverse EMT in HCC cells, indicating that OCT4 plays a critical role in HCC progression. Our data suggest that the pathogenesis of human HCC may be mediated by OCT4, and thus, OCT4 could represent selective targets for the molecularly targeted treatments of HCC.

MRC-5 fibroblast-conditioned medium influences multiple pathways regulating invasion, migration, proliferation, and apoptosis in hepatocellular carcinoma

Background

Carcinoma associated fibroblasts (CAFs), an important component of tumor microenvironment, are capable of enhancing tumor cells invasion and migration through initiation of epithelial–mesenchymal transition (EMT). MRC-5 fibroblasts are one of the CAFs expressing alpha-smooth muscle actin. It is ascertained that medium conditioned by MRC-5 fibroblasts stimulate motility and invasion of breast cancer cells. However, its role in hepatocellular carcinoma (HCC) is less clear. The aim of our study was to investigate the effect of MRC-5-CM on HCC and explore the underlying mechanisms.

Methods and results

Using a combination of techniques, the role of MRC-5-CM in HCC was evaluated. We determined that MRC-5-CM induced the non-classical EMT in Bel-7402 and MHCC-LM3 cell lines. Initiation of the non-classical EMT was mainly via quintessential redistribution of α-, β- and γ-catenin, P120 catenin, E-cadherin, and N-cadherin, rather than up-regulation of typical EMT-related transcription factors (i.e., Snail, Twist1, ZEB-1 and ZEB2). We also found that MRC-5-CM potentiated both the migration and invasion of Bel-7402 and MHCC-LM3 cells in mesenchymal movement mode through activation of the α6, β3, β4, β7 integrin/FAK pathway and upregulation of MMP2. The flow cytometric analysis showed that MRC-5-CM induced G1 phase arrest in Bel-7402 cells with a concomitant reduction of S phase cells. In contrast, MRC-5-CM induced S phase arrest in MHCC-LM3 cells with a concomitant reduction of cells in the G2/M phase. MRC-5-CM also inhibited apoptosis in Bel-7402 cells while inducing apoptosis in MHCC-LM3 cells.

Conclusion

Collectively, MRC-5-CM promoted HCC cell motility and invasiveness through initiation of the non-classical EMT, including redistribution of α-, β- and γ-catenin, P120 catenin, E-cadherin, and N-cadherin, activation of the integrin/FAK pathway, and upregulation of MMP2. Hence, MRC-5-CM exerted distinct roles in Bel-7402 and MHCC-LM3 cell viability by regulating cyclins, cyclin dependent kinases (CDKs), CDK inhibitors (CKIs), Bcl-2 family proteins and other unknown mechanosensors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0588-8) contains supplementary material, which is available to authorized users.

Aptamer-based Sandwich Assay and its Clinical Outlooks for Detecting Lipocalin-2 in Hepatocellular Carcinoma (HCC)

We validated a single-stranded, DNA aptamer-based, diagnostic method capable of detecting Lipocalin-2 (LCN2), a biomarker from clinically relevant hepatocellular carcinoma (HCC) patient serum, in the sandwich assay format. Nine aptamers (LCN2_apta1 to LCN2_apta9) for LCN2 were screened with SELEX processes, and a sandwich pair (LCN2_apta2 and LCN2_apta4) was finally chosen using surface plasmon resonance (SPR) and dot blotting analysis. The result of the proposed aptamer sandwich construction shows that LCN2 was sensitively detected in the concentration range of 2.5–500 ng mL⁻¹ with a limit of detection of 0.6 ng mL⁻¹. Quantitative measurement tests in HCC patients were run on straight serum and were compared with the performance of the conventional antibody-based ELISA kit. The aptamer sandwich assay demonstrated an excellent dynamic range for LCN2 at clinically relevant serum levels, covering sub-nanogram per mL concentrations. The new approach offers a simple and robust method for detecting serum biomarkers that have low and moderate abundance. It consists of functionalization, hybridization and signal read-out, and no dilution is required. The results of the study demonstrate the capability of the aptamer sandwich assay platform for diagnosing HCC and its potential applicability to the point-of-care testing (POCT) system.

Circulating tumor and cancer stem cells in hepatitis C virus-associated liver disease

AIM: To assess the role of circulating tumor cells (CTCs) and cancer stem cells (CSCs) in hepatitis C virus (HCV)-associated liver disease.

METHODS: Blood and/or tissue samples were obtained from HCV (genotype 4)-associated hepatocellular carcinoma patients (HCC; n = 120), chronic hepatitis C patients (CH; n = 30) and 33 normal control subjects (n = 33). Serum levels of alpha-fetoprotein (AFP), alkaline phosphatase, and alanine and aspartate aminotransferases were measured. Cytokeratin 19 (CK19) monoclonal antibody was used to enumerate CTCs, and CD133 and CD90 were used to enumerate CSCs by flow cytometry. The expression levels of the CSCs markers (CD133 and CD90) as well as telomerase, melanoma antigen encoding gene 1 (MAGE1) and MAGE3 were assessed by RT-PCR and quantitative real-time polymerase chain reactions. The number of CTCs and/or the expression levels of CK19, CD133, telomerase, MAGE1 and MAGE3 were correlated to the standard clinicopathologic prognostic factors and disease progression.

RESULTS: Levels of AFP, alkaline phosphatase and aspartate aminotransferase were significantly different among the HCC, CH and control groups (P < 0.001), whereas alanine aminotransferase differed significantly between patient (HCC and CH) and control groups (P < 0.001). At the specified cutoff values determine by flow cytometry, CK19 (49.8), CD90 (400) and CD133 (73) were significantly higher in the blood of HCC patients compared to those in the CH and control groups (P < 0.001). On the other hand, CD133 at a 69.5 cutoff was significantly higher in the CH compared to the control group (P≤ 0.001). Telomerase, MAGE1 and MAGE3 RNA were expressed in 55.71%, 60.00% and 62.86% of the HCC patients, respectively, but were not detected in patients in the CH or control groups, which were statistically significant (Ps < 0.001). The expression levels of telomerase, CD90, MAGE3, CD133 and CK19 were all significantly associated with high tumor grade and advanced stage in HCC patients (all Ps < 0.05).

CONCLUSION: CTC counts and AFP, CK19, telomerase, and MAGE1/MAGE3 expression predict disease progression in patients with HCV, whereas telomerase, MAGE3, CD90, CD133 and CK19 are prognostic markers in HCC.

CD26-positive/CD326-negative circulating cancer cells as prognostic markers for colorectal cancer recurrence

The present study evaluated the presence and clinical relevance of a cluster of differentiation (CD)26⁺/CD326^- subset of circulating tumor cells (CTCs) in pre- and post-operative blood samples of colorectal cancer patients, who had undergone curative or palliative intervention, in order to find a novel prognostic factor for patient management and follow-up. In total, 80 colorectal cancer patients, along with 25 healthy volunteers were included. The easily transferable methodology of flow cytometry, along with multiparametric antibody staining were used to selectively evaluate CD26⁺/CD326^- CTCs in the peripheral blood samples of colorectal cancer patients. The multiparametric selection allowed any enrichment methods to be avoided thus rendering the whole procedure suitable for clinical routine. The presence of CD26⁺/CD326^- cells was higher in advanced Dukes' stages and was significantly associated with poor survival and high recurrence rates. Relapsing and non-surviving patients showed the highest number of CD26⁺/CD326^- CTCs. High pre-operative levels of CD26⁺/CD326^- CTCs correctly predicted tumor relapse in 44.4% of the cases, while 69% of post-operative CD26⁺/CD326^- CTC-positive patients experienced cancer recurrence, with a test accuracy of 88.8%. By contrast, post-operative CD26⁺/CD326^- CTC-negative patients showed an increase in the three-year progression-free survival rate of 86%, along with a reduced risk of tumor relapse of >90%. In conclusion, CD26⁺/CD326^- CTCs are an independent prognostic factor for tumor recurrence rate in multivariate analysis, suggesting that their evaluation could be an additional factor for colorectal cancer recurrence risk evaluation in patient management.

Inflammatory cytokines promote the retrodifferentiation of tumor-derived hepatocyte-like cells to progenitor cells

Human hepatocellular carcinoma (HCC) heterogeneity promotes recurrence and resistance to therapies. Recent studies have reported that HCC may be derived not only from adult hepatocytes and hepatoblasts but also hepatic stem/progenitors. In this context, HepaRG cells may represent a suitable cellular model to study stem/progenitor cancer cells and the retrodifferentiation of tumor-derived hepatocyte-like cells. Indeed, they differentiate into hepatocyte- and biliary-like cells. Moreover, tumor-derived HepaRG hepatocyte-like cells (HepaRG-tdHep) differentiate into both hepatocyte- and biliary-like cells through a hepatic progenitor. In this study we report the mechanisms and molecular effectors involved in the retrodifferentiation of HepaRG-tdHep into bipotent progenitors. Gene expression profiling was used to identify genomic changes during the retrodifferentiation of HepaRG-tdHep into progenitors. We demonstrated that gene expression signatures related to a poor-prognosis HCC subclass, proliferative progenitors, or embryonic stem cells were significantly enriched in HepaRG progenitors derived from HepaRG-tdHep. HepaRG-tdHep retrodifferentiation is mediated by crosstalk between transforming growth factor beta 1 (TGFβ1) and inflammatory cytokine pathways (e.g., tumor necrosis factor alpha [TNFα] and interleukin 6 [IL6]). Signatures related to TNFα, IL6, and TGFβ activation pathways are induced within the first hour of retrodifferentiation. Moreover, specific activation or inhibition of these signaling pathways allowed us to determine that TNFα and IL6 contribute to the loss of hepatic-specific marker expression and that TGFβ1 induces an epithelial-to-mesenchymal transition of HepaRG-tdHep. Interestingly, the retrodifferentiation process is blocked by the histone deacetylase inhibitor trichostatin A, opening new therapeutic opportunities.

CONCLUSION

Cancer progenitor cells (or metastasis progenitors) may derive from tumor-derived hepatocyte-like cells in an inflammatory environment that is frequently associated with HCC.

Role of circulating tumor cells and cancer stem cells in hepatocellular carcinoma

Circulating tumor cells (CTC) and cancer stem cells (CSC) have been proposed as tools for detection and characterization of disease and individualization of therapy in patients with many solid tumors. Several automated and semi-automated techniques for identification and isolation of these cells from blood have been proposed and reviewed mostly focusing on their feasibility. In this mini review we summarize the recent relevant literature on this topic and discuss the clinical usability of measuring CTC and CSC in peripheral blood in patients with hepatocellular carcinoma (HCC). Besides literature, the basis for this evaluation was the authors' experience with treating HCC and research experience on CSC and CTC. Few original reports and reviews have been published focusing on CTC and CSC in HCC. Though HCC is one of the five most common malignancies worldwide only recently these cells have come into focus for detection and characterization of this disease that is characterized by high plasticity and malignancy. A focused and prospective validation of the clinical usability of detecting these cells in HCC is still needed, but results seem promising that they may add great benefit for early detection and individualization of therapy.

Targeting of circulating hepatocellular carcinoma cells to prevent postoperative recurrence and metastasis

Currently, the main treatment for hepatocellular carcinoma (HCC) involves the surgical removal of tumors or liver transplantation. However, these treatments are often not completely curative, as they are associated with a risk for postoperative recurrence and metastasis. Circulating tumor cells (CTCs) are increasingly recognized as the main source for recurrence and metastasis after radical hepatectomies are performed. Many studies have demonstrated the association between the presence of either pre- or postoperative CTCs and an increased risk for HCC recurrence. To improve the therapeutic outcome of HCC, a personalized, comprehensive and multidisciplinary approach should be considered, involving the application of appropriate diagnostic and therapeutic measures targeting HCC CTCs in different stages throughout the course of treatment. This article proposes some HCC CTC-based strategies for the treatment of HCC, including the monitoring of HCC CTCs before, during and after radical hepatectomy, therapeutic targeting of HCC CTCs, prevention of the generation and colonization of CTCs, as well as the use of CTC indexes for the selection of indications, prediction of prognoses, and planning of individualized therapeutic regimens. Innovation and technological development of therapies targeting CTCs, as well as their translation into clinical practice, will help to effectively reduce postoperative recurrence and metastasis, and significantly prolong the survival of HCC patients.

Water soluble fluorescence quantum dot probe labeling liver cancer cells

Water soluble quantum dots (QDs) have been prepared by hydrothermal method and characterized by ultraviolet irradiation, XRD, TEM, UV-Vis absorption spectrometer and fluorescence spectrometer. Then the QD-antibody-AFP probes (QD-Ab-AFP) were synthesized by chemical process and specifically labeled AFP antigen in PLC/PRF/5 liver cancer cells. The results showed that the QDs were cubic structure and had excellent optical properties. Moreover, the QD-Ab-AFP with good stability could specifically label liver cancer cells. This work provides strong foundation for further studying and developing new approach to detect liver cancer at early stage.

Postoperative detection of circulating tumor cells predicts tumor recurrence in colorectal cancer patients

INTRODUCTION

Circulating tumor cells are thought to play a crucial role in the development of distant metastases. Their detection in the blood of colorectal cancer patients may be linked to poor outcome, but current evidence is controversial.

MATERIALS AND METHODS

Pre- and postoperative flow cytometric analysis of blood samples was carried out in 76 colorectal cancer patients undergoing surgical resection. The EpCAM/CD326 epithelial surface antigen was used to identify circulating tumor cells.

RESULTS

Fifty-four (71%) patients showed circulating tumor cells preoperatively, and all metastatic patients showed high levels of circulating tumor cells. Surgical resection resulted in a significant decrease in the levels of circulating tumor cells. Among 69 patients undergoing radical surgery, 16 had high postoperative levels of circulating tumor cells, and 12 (75%) experienced tumor recurrence. High postoperative level of circulating tumor cells was the only independent variable related to cancer relapse. In patients without circulating tumor cells, the progression-free survival rate increased from 16 to 86%, with a reduction in the risk of tumor relapse greater than 90%.

CONCLUSIONS

High postoperative levels of circulating tumor cells accurately predicted tumor recurrence, suggesting that assessment of circulating tumor cells could optimize tailored management of colorectal cancer patients.

Circulating tumor cells: utopia or reality?

Circulating tumor cells (CTCs) could be considered a sign of tumor aggressiveness, but highly sensitive and specific methods of CTC detection are necessary owing to the rarity and heterogeneity of CTCs in peripheral blood. This review summarizes recent studies on tumor biology, with particular attention to the metastatic cascade, and the molecular characterization and clinical significance of CTCs. Recent technological approaches to enrich and detect these cells and challenges of CTCs for individualized cancer treatment are also discussed. This review also provides an insight into the positive and negative features of the future potential applications of CTC detection, which sometimes remains still a ‘utopia’, but its actual utility remains among the fastest growing research fields in oncology.

Recognition and capture of metastatic hepatocellular carcinoma cells using aptamer-conjugated quantum dots and magnetic particles

Metastatic recurrence is the most important biological behavior of hepatocellular carcinoma (HCC) and the main cause of treatment failure. Early prediction of metastasis is currently impossible due to the lack of specific molecular probes to recognize metastatic HCC cells. Aptamers have recently emerged as promising potential molecular probes for biomedical applications. Two well-matched HCC cell lines including HCCLM9 with high metastatic potential and MHCC97-L with low metastatic potential, were used to select aptamers for HCC metastasis. With a whole-cell-SELEX strategy, in which HCCLM9 cells were used as target cells and MHCC97-L cells as subtractive cell, 6 potential aptamers had been generated. Detailed study on selected aptamer LY-1 revealed that it could bind metastatic HCC cells with high affinity and specificity, not only in cells culture and animal models of HCC metastasis, but also in clinical HCC specimens. Moreover, the aptamer LY-1 and magnetic particles conjugates could efficiently capture the HCC cells from complex mixture whole blood. These studies demonstrated that this HCC specific aptamer LY-1 could be a promising molecular probe to recognize metastatic HCC cells.

Combined analysis of serum γ-glutamyl transferase isoenzyme II, α-L-fucosidase and α-fetoprotein detected using a commercial kit in the diagnosis of hepatocellular carcinoma

γ-glutamyl transferase isoenzyme II (GGT-II) is a sensitive biomarker of hepatocellular carcinoma (HCC). However, numerous disadvantages of the traditional manual method affected its application. The commercial kit provided a convenient and fast method for the determination of GGT-II levels. The purposes of the present study were to compare the reproducibility and sensitivity between the manual and commercial kit methods and to evaluate the diagnostic efficiency for HCC with the combined analysis of GGT-II, α-L-fucosidase (AFU) and α-fetoprotein (AFP). In patients with various liver diseases (HCC, liver cirrhosis and chronic hepatitis) and normal subjects, GGT-II was detected by manual and commercial polyacrylamide gel electrophoresis (PAGE). The levels of AFU and AFP were assayed by colorimetry and a chemiluminescence immunoassay, respectively. The commercial PAGE had equal diagnostic efficiency with traditional manual PAGE and no significant differences were observed in intra- and average-gel reproducibility and GGT-II sensitivities between the manual and commercial PAGE (P>0.05). The incidence of GGT-II detected by commercial PAGE in HCC patients was 84.1% and <8% in benign liver disease. The levels of AFU and AFP in the benign liver diseases and normal subjects were lower than those in HCC. According to the cut-off value obtained by receiver operating characteristic curves, a total of 56.6 and 59.3% of HCC patients (64 out of 113 and 67 out of 113) had AFU >636.5 μmol/l h and AFP >44.0 μg/l, respectively. There were no significant correlations between GGT-II and AFU or AFP. Combined detection of GGT-II with AFU or AFP increased the diagnostic sensitivity to 92.9 and 93.8%, respectively. These results suggest that commercial PAGE provides a simple and reproducible method for GGT-II detection. Combined determination of GGT-II with AFU or AFP exhibited superior sensitivity and specificity for the diagnosis of HCC.

Mast cells, disease and gastrointestinal cancer: A comprehensive review of recent findings

Paul Ehrlich, a German scientist, discovered what is known as the mast cell in the late 1800's, which has proven to be an important player in the immune system of vertebrates. Mast cells are ubiquitous throughout the tissues of the human body and play numerous roles, both beneficial and destructive. We know they are important in our army of immunity warrior cells, which defend us against viruses, bacteria and parasitic invaders. They are also very well known for the havoc they wreak, causing uncomfortable symptoms due to their release of histamine and other mediators which cause the all too familiar itching, sneezing, urticaria and rhinorrhea of allergic responses. Mast cell activities are diverse and include painful inflammatory reactions in autoimmune conditions such as rheumatoid arthritis. In the gastrointestinal system, mast cells are implicated in diverse actions such as increased gastric acid secretion, polyp formation and uncomfortable conditions such as Irritable Bowel Syndrome. The role of immunology and mast cells in these areas is intriguing but less well understood than their role in allergic responses. Because mast cells have been implicated in both physiologic as well as pathogenic processes, they have been the subjects of avid study. Review of the current literature on mast cell biology reveals that there are many studies of their presence within the tumor microenvironment and evidence, which supports mast cell influence on tumor angiogenesis, tumor invasion, and immune suppression. The studies reviewed in this article concentrate largely on mast cells in human GI malignancies. This review also provides background information regarding mast cells, such as their origination, their location within the body, how they are activated and how they function as mediators.