The biology of cancer stem cells and its clinical implication in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly malignant tumor with limited treatment options in its advanced state. The molecular mechanisms underlying HCC remain unclear because of the complexity of its multi-step development process. Cancer stem cells (CSCs) are defined as a small population of cells within a tumor that possess the capability for self-renewal and the generation of heterogeneous lineages of cancer cells. To date, there have been two theories concerning the mechanism of carcinogenesis, i.e., the stochastic (clonal evolution) model and the hierarchical (cancer stem cell-driven) model. The concept of the CSC has been established over the past decade, and the roles of CSCs in the carcinogenic processes of various cancers, including HCC, have been emphasized. Previous experimental and clinical evidence indicated the existence of liver CSCs; however, the potential mechanistic links between liver CSCs and the development of HCC in humans are not fully understood. Although definitive cell surface markers for liver CSCs have not yet been found, several putative markers have been identified, which allow the prospective isolation of CSCs from HCC. The identification and characterization of CSCs in HCC is essential for a better understanding of tumor initiation or progression in relation to signaling pathways. These markers could be used along with clinical parameters for the prediction of chemoresistance, radioresistance, metastasis and survival and may represent potential targets for the development of new molecular therapies against HCC. This review describes the current evidence for the existence and function of liver CSCs and discuss the clinical implications of CSCs in patients demonstrating resistance to conventional anti-cancer therapies, as well as clinical outcomes. Such data may provide a future perspective for targeted therapy in HCC.     

人肝细胞癌细胞亚群的克隆分离及异质性机制的初步研究

目的:通过原代培养人肝癌细胞、克隆分离异质性亚群细胞,探讨肝癌异质性机制．方法:原代培养人肝细胞癌细胞,应用有限稀释法对培养的肝癌细胞进行单细胞克隆分离异质性亚群,并应用细胞计数法测定其细胞倍增时间及倍增数,流式细胞仪检测其DNA含量确定细胞周期分布,裸鼠异体移植检测其成瘤能力．结果:分离到LCSC-1及LCSC-2两个细胞亚群．LCSC-1亚群细胞呈长梭形,裸鼠异体移植不能成瘤(0／8);LCSC-2亚群细胞呈多角形、多突起,裸鼠异体移植可成瘤(8／8)．LCSC-1与 LCSC-2相比,体外增殖能力强,倍增时间(18．6 ±3．2 h vs 25．9±4．7 h)和最大倍增倍数(16．1 ±1.4 vs 12．2±1．6)有显著差异(均P<0．01);而且LCSC-1处于细胞周期S(28．4％±3．3％vs 20．2％±1．9％,P<0．01)和G2M(25．0％±6．3％ vs 16．6％±4．7％,P<0．05)的比例明显高于 LCSC-2．结论:原发性肝细胞癌中存在着异质性的肿瘤细胞亚群,可能来源于肿瘤干细胞的分化．     

Gene therapy of liver cancer

INTRODUCTION Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy. This new discipline is based on the transfer of gen…     

Prognostic implication of early posttransplant hypercholesterolemia in liver transplantation for patients with hepatocellular carcinoma

Background: Hyperlipidemia is a common complication after liver transplantation(LT) and develops mostly in the early posttransplant period. Recently, some studies have reported a positive correlation between hyperlipidemia and favorable prognosis in patients with hepatocellular carcinoma(HCC) undergoing hepatectomy. This study aimed to evaluate the possibility of predicting prognosis in HCC patients receiving LT by early posttransplant dyslipidemia. Methods: From January 2015 to December 2017, a...     

Hepatic cancer stem cells and drug resistance: Relevance in targeted therapies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of most common malignancies in the world. Systemic treatments for HCC, particularly for advanced stages, are limited by the drug resistance phenomenon which ultimately leads to therapy failure. Recent studies have indicated an association between drug resistance and the existence of the cancer stem cells (CSCs) as tumor initiating cells. The CSCs are resistant to conventional chemotherapies and might be related to the mechanisms of the ATP Binding Cassette (ABC) transporters and alterations in the CSCs signaling pathways. Therefore, to contribute to the development of new HCC treatments, further information on the characterization of CSCs, the modulation of the ABC transporters expression and function and the signaling pathway involved in the self renewal, initiation and maintenance of the cancer are required. The combination of transporters modulators/inhibitors with molecular targeted therapies may be a potent strategy to block the tumoral progression. This review summarizes the association of CSCs, drug resistance, ABC transporters activities and changes in signaling pathways as a guide for future molecular therapy for HCC.     

免疫治疗时代下的肝癌肝移植

我国大部分肝癌患者在就诊时不能获得根治性手术治疗,近年来肝癌免疫治疗的突破性进展为这些中晚期肝癌患者带来了曙光。在肝癌肝移植领域,免疫治疗更是因为在肿瘤免疫和移植免疫中扮演的双重角色而备受关注。在术前降期治疗和移植术后肿瘤复发的治疗中均有创新性的应用。在免疫治疗的时代下如何应用移植肿瘤学思维使肝癌肝移植患者获益是一个崭新的课题,这需要在临床实践中进行多学科团队协作,探讨最佳的肝癌肝移植患者治疗策略,最终改善中晚期肝癌患者的预后。     

Hepatocellular carcinoma and synchronous liver metastases from colorectal cancer in cirrhosis: A case report

A 68-year-old Caucasian man with hepatitis C virus-related cirrhosis was admitted to our Unit in February 2010 for a diagnostic evaluation of three centimetric hypoechoic focal liver lesions detected by regular surveillance ultrasound. The subsequent computer tomography (CT) led to a diagnosis of unifocal hepatocellular carcinoma (HCC) in VI hepatic segment, defined the other two nodules in the VI and VII segment as suspected metastases, and showed a luminal narrowing with marked segmental circumferential thickening of the hepatic flexure of the colon. Colonoscopy detected an ulcerated, bleeding and stricturing lesion at the hepatic flexure, which was subsequently defined as adenocarcinoma with a moderate degree of differentiation at histological examination. Finally, ultrasound-guided liver biopsy of the three focal liver lesions confirmed the diagnosis of HCC for the nodule in the VI segment, and characterized the other two lesions as metastases from colorectal cancer. The patient underwent laparotomic right hemicolectomy with removal of thirty-nine regional lymph nodes (three of them tested positive for metastasis at histological examination), and simultaneous laparotomic radio-frequency ablation of both nodule of HCC and metastases. The option of adjuvant chemotherapy was excluded because of the post-surgical onset of ascites. Abdomen CT and positron emission tomography/CT scans performed after 1, 6 and 12 mo highlighted a complete response to treatments without any radiotracer accumulation. After 18 mo, the patient died due to progressive liver failure. Our experience emphasizes the potential coexistence of two different neoplasms in a cirrhotic liver and the complexity in the proper diagnosis and management of the two tumours.     

Surgical treatment for liver cancer

Primary liver cancer is amongst the commonest tumors worldwide,particularly in parts of the developing world,and is increasing in incidence. Over the past three decades,surgical hepatic resection has evolved from a high risk,resource intensive procedure with limited application,to a safe and commonly performed operation with a range of indications. This article reviews the approach to surgical resection for malignancies such as hepatocellular cancer,metastatic liver de-posits and neuroendocrine tumors. Surv...     

Up-to-seven criteria for hepatocellular carcinoma liver transplantation:A single center analysis

AIM:To detect whether the up-to-seven should be used as inclusion criteria for liver transplantation for hepatocellular carcinoma.METHODS:Between April 2002 and July 2008,220hepatocellular carcinoma(HCC)patients who were diagnosed with HCC and underwent liver transplantation(LT)at our liver transplantation center were included.These patients were divided into three groups according to the characteristics of their tumors(tumor diameter,tumor number):the Milan criteria group(Group 1),the in up-to-seven group(Group 2)and the out up-toseven group(Group 3).Then,we compared long-term survival and tumor recurrence of these three groups.RESULTS:The baseline characteristics of transplant recipients were comparable among these three groups,except for the type of liver graft(deceased donor liver transplant or live donor liver transplantation).There were also no significant differences in the pre-operativeα-fetoprotein level.The 1-,3-,and 5-year overall survival and tumor-free survival rate for the Milan criteriagroup were 94.8%,91.4%,89.7%and 91.4%,86.2%,and 86.2%respectively;in the up-to-seven criteria group,these rates were 87.8%,77.8%,and 76.6%and 85.6%,75.6%,and 75.6%respectively(P<0.05).However,the advanced HCC patients’(in the group out of up-to-seven criteria)overall and tumor-free survival rates were much lower,at 75%,53.3%,and 50%and65.8%,42.5%,and 41.7%,respectively(P<0.01).CONCLUSION:Considering that patients in the up-toseven criteria group exhibited a considerable but lower survival rate compared with the Milan criteria group,the up-to-seven criteria should be used carefully and selectively.     

肝癌组织乙酰肝素酶的表达及其与微血管密度的关系

目的观察乙酰肝素酶（Hpa）在肝癌组织中的表达,并探讨其与微血管密度（MVD）的关系。方法采用RT-PCR法检测47例原发性肝癌组织、癌旁组织1（A组）和癌旁组织2（B组）Hpa mRNA水平;采用免疫组织化学法检测肝癌组织Hpa蛋白和CD34表达水平,并分析Hpa蛋白与肝癌临床病理特征的关系,以及Hpa mRNA水平与MVD值的相关性。结果在不同直径和分化程度、不同临床分期、是否转移复发、AFP水平和有无门脉癌栓等肿瘤组织,Hpa蛋白表达存在明显的差异（P<0.05）;肝癌组织Hpa mRNA水平（0.793±0.184）和MVD值（34.5±12.2）均明显高于A组和B组（P<0.05）,而A组Hpa mRNA水平（0.577±0.145）和MVD值（22.2±10.7）又明显高于B组[（0.384±0.117）和（14.7±7.4）,P<0.05];各组Hpa mRNA水平与MVD值呈正相关（r=0.627,P<0.05）。结论Hpa在肝癌的生长、侵袭和血管生成中发挥着重要作用。     

Prognostic value of 18F-FDG PET/CT in liver transplantation for hepatocarcinoma

AIM:To evaluate the prognostic value of pretreatment F D G p o s i t r o n e m i s s i o n t o m o g ra p h y c o m p u t e d tomography(PET-CT) in patients with hepatocarcinoma treated by liver transplantation(LT).METHODS:The authors retrospectively analyzed the data of 27 patients(mean age 58 ± 9 years) who underwent FDG PET-CT before LT for hepatocarcinoma.Mean follow-up was 26 ± 18 mo.The FDG PET/CT was performed according to a standard clinical protocol:4 MBq FDG/kg body weight,uptake 60 min,low-dose non-enhanced CT.The authors measured the SUVmax and SUVmean of the tumor and the normal liver.The tumor/liver activity ratios(RSUVmax and RSUVmean) were tested as prognostic factors and compared to the following conventional prognostic factors:MILAN,CLIP,OKUDA,TNM stage,alphafoetoprotein level,portal thrombosis,size of the largest nodule,tumor differentiation,microvascular invasion,underlying cirrhosis and liver function.RESULTS:Overall and recurrence free survivals were80.7%and 67.4%at 3 years,and 70.6%and 67.4%at 5 years,respectively.According to a multivariate Cox model,only FDG PET/CT RSUVmax predicted recurrence free survival.Even though the MILAN criteria alone were not predictive,it is worth noting that none of the patients outside the MILAN criteria and with RSUVmax1.15 relapsed.CONCLUSION:FDG PET/CT with an RSUVmax cutoff value of 1.15 is a strong prognostic factor for recurrence and death in patients with HCC treated by LT in this retrospective series.Further prospectivestudies should test whether this metabolic index should be systematically included in the preoperative assessment.     

Use of a saline-coupled bipolar sealer open liver resection for hepatic malignancy: Medical resource use and costs

AIM To evaluate outcomes associated with use of a saline coupled bipolar sealer during open partial liver resection.METHODS This retrospective analysis utilized the United States Premier? insurance claims database(2010-2014). Patients were selected with codes for liver malignancy and partial hepatectomy or lobectomy. Cases were defined by use the saline-coupled bipolar sealer; controls had no use. A Propensity Score algorithm was used to match one case to five controls. A deviationbased cost modeling(DBCM) approach provided an estimate of cost-effectiveness.RESULTS One hundred and forty-four cases and 720 controls were available for analysis. Patients in the case cohort received fewer transfusions vs controls(18.1% vs 29.4%, P = 0.007). In DBCM, more patients in the case cohort experienced "on-course" hospitalizations(53.5% vs 41.9%, P = 0.009). The cost calculation showed an average savings in total hospitalization costs of $1027 for cases vs controls. In multivariate analysis, cases had lower odds of receiving a transfusion(OR = 0.44, 95%CI: 0.27-0.71, P = 0.0008).CONCLUSION Use of a saline-coupled bipolar sealer was associated with a greater proportion of patients with an "on course" hospitalization.     

A prediction model for liver abscess developing after transarterial chemoembolization in patients with hepatocellular carcinoma

BackgroundLiver abscess is a rare but potentially fatal complication of transarterial chemoembolization. Other than for biliary abnormalities, risk factors for liver abscess formation after transarterial chemoembolization have rarely been discussed.AimsTo identify other risk factors of liver abscess after transarterial chemoembolization in patients with hepatocellular carcinoma.MethodsData for 5299 patients with hepatocellular carcinoma who underwent transarterial chemoembolization from July 1999 to December 2009 were retrospectively reviewed. 72 patients who experienced liver abscess after transarterial chemoembolization were enrolled as a case group, which was compared with a randomly selected control group (n = 1009) of patients who did not develop liver abscess after transarterial chemoembolization.ResultsPneumobilia, type 2 biliary abnormality, type 1 biliary abnormality, diabetes mellitus, tumour number (≥3), tumour size (≥3 cm), and tumour necrosis on the pre-transarterial chemoembolization computed tomography, and gelfoam embolization and vessel injury during transarterial chemoembolization were all significant predisposing factors for liver abscess after transarterial chemoembolization. A prediction model for postembolization liver abscess was developed from these risk factors.ConclusionThe group of patients with risk scores greater than 71 showed a significantly increased risk of liver abscess after transarterial chemoembolization. These high-risk patients should be monitored carefully after transarterial chemoembolization.     

Prediction of post-hepatectomy liver failure and long-term prognosis after curative resection of hepatocellular carcinoma using liver stiffness measurement

Background and study aimsPost-hepatectomy liver failure (PHLF) is the main cause of perioperative death after hepatocellular carcinoma (HCC) resection. PHLF occurrence is related to both the hepatectomy volume and the degree of cirrhosis. Accurate preoperative assessment of the degree of cirrhosis may aid in reducing the incidence of PHLF. Several studies have shown that the liver stiffness measurement (LSM) is well correlated with cirrhosis. This study explored the relationship between LSM and PHLF occurrence after radical HCC resection and the effect on long-term prognosis.Patients and methodsWe retrospectively analyzed the clinical data of 164 patients who underwent radical HCC resection at our center from January 2017 to January 2020. The related postoperative PHLF factors were analyzed. The LSM threshold in postoperative PHLF was calculated through receiver operating characteristic (ROC) curve analysis. Patients were grouped according to different LSM thresholds and survival analysis was performed.ResultsForty-six patients experienced PHLF, of whom 19, 21, and 6 were classified as grades A, B, and C, respectively. Multivariate analysis indicated that LSM was an independent risk factor for PHLF after HCC surgery (OR = 1.174, P < 0.000). LSM (OR = 1.219, P < 0.000) and intraoperative bleeding (OR = 1.001, P = 0.047) were risk factors for grade B-C PHLF. The LSM threshold that predicted PHLF occurrence was 17.9 kPa (AUC = 0.831, P < 0.000) and 24.5 kPa (AUC = 0.867, P < 0.000) for grade B-C PHLF. LSM was correlated with PHLF severity (r = 0.439, P < 0.001). The median survival times were 32 vs 26 months (P = 0.016) for patients with LSM ≤ 17.9 kPa vs those with LSM > 17.9 kPa and 28 vs 24 months (P = 0.004) for patients with LSM ≤ 24.5 kPa vs those with LSM > 24.5 kPa.ConclusionLSM is related to PHLF occurrence in patients undergoing HCC resection; a higher LSM is associated with the occurrence of more severe PHLF after surgery. In addition, LSM may aid in predicting long-term survival after liver resection in patients with HCC.     

Assessment of hepatic functional reserve by cirrhosis grading and liver volume measurement using CT

AIM： To explore a method for quantitative assessment of hepatic functional reserve by combining computed tomography （CT） volumetry with CT grading of liver cirrhosis before liver resection in patients with hepatocellular carcinoma.
METHODS： CT images of 55 patients undergoing liver resection were studied prospectively. The degree of liver cirrhosis was referred as ＂CT grade＂ and the percentage of remnant liver volume （PRLV） [PRLV = predicted RLV/predicted total liver volume （PTLV） × 100%; PTLV （mL） = 121.75 ＋ 16.49 × body mass （kg）] were calculated by adding slice by slice of CT liver images. The postoperative RLV, pathologic stages of liver fibrosis in non-tumor area and survival time in these cases were analyzed.
RESULTS： There was a significant difference in survival time between the group with PRLV ≤ 50% and the group with PRLV 〉 50% （X^2= 4.988, P = 0.026）, and between the group with CT grade 0/1 and the group with CT grade 2/3 （X^2= 5.429, P = 0.026）. With combination of the both parameters, an oblique line was identified according to the distribution of 32 survivors versus 23 deceased subjects. The mortality rate above the line was 7.1% （1/14）, and that below the line was 53.7% （22/41）, indicating a significant difference between the two rates （X^2 = 9.281, P = 0.002, P 〈 0.05）. CONCLUSION： PRLV and CT grades are significantly correlated with hepatic functional reserve. The predicted line using these two parameters is useful in candidates undergoing liver resection for judging hepatic functional reserve.     

Association of nonalcoholic fatty liver disease and liver cancer

AIM:To investigate the association between nonalcoholic fatty liver disease(NAFLD) and liver cancer,and NAFLD prevalence in different liver tumors.METHODS:This is a retrospective study of the clinical,laboratory and histological data of 120 patients diagnosed with primary or secondary hepatic neoplasms and treated at a tertiary center where they underwent hepatic resection and/or liver transplantation,with subsequent evaluation of the explant or liver biopsy.The following criteria were used to exclude patients from the study:a history of alcohol abuse,hepatitis B or C infection,no tumor detected in the liver tissue examined by histological analysis,and the presence of chronic autoimmune hepatitis,hemochromatosis,Wilson’s disease,or hepatoblastoma.The occurrence of NAFLD and the association with its known risk factors were studied.The risk factors considered were diabetes mellitus,impaired glucose tolerance,impaired fasting glucose,body mass index,dyslipidemia,and arterial hypertension.Presence of reticulin fibers in the hepatic neoplasms was assessed by histological analysis using slide-mounted specimens stained with either hematoxylin and eosin or Masson’s trichrome and silver impregnation.Analysis of tumor-free liver parenchyma was carried out to determine the association between NAFLD and its histological grade.RESULTS:No difference was found in the association of NAFLD with the general population(34.2% and 30.0% respectively,95%CI:25.8-43.4).Evaluation by cancer type showed that NAFLD was more prevalent in patients with liver metastasis of colorectal cancer than in patients with hepatocellular carcinoma and intrahepatic cholangiocarcinoma(OR = 3.99,95%CI:1.78-8.94,P < 0.001 vs OR = 0.60,95%CI:0.18-2.01,P = 0.406 and OR = 0.70,95%CI:0.18-2.80,P = 0.613,respectively).There was a higher prevalence of liver fibrosis in patients with hepatocellular carcinoma(OR = 3.50,95%CI:1.06-11.57,P = 0.032).Evaluation of the relationship between the presence of NAFLD,nonalcoholic steatohepatitis,and liver fibrosis,and their risk factors,showed no significant statistical association for any of the tumors studied.CONCLUSION:NAFLD is more common in patients with liver metastases caused by colorectal cancer.     

Research progress and prospects of markers for liver cancer stem cells

Liver cancer is a common malignancy and surgery is the main treatment strategy. However, the prognosis is still poor because of high frequencies of postoperative recurrence and metastasis. In recent years, cancer stem cell(CSC) theory has evolved with the concept of stem cells, and has been applied to oncological research. According to cancer stem cell theory, liver cancer can be radically cured only by eradication of liver cancer stem cells(LCSCs). This notion has lead to the isolation and identification of LCSCs, which has become a highly researched area. Analysis of LCSC markers is considered to be the primary method for identification of LCSCs. Here, we provide an overview of the current research progress and prospects of surface markers for LCSCs.