Silencing alpha-fetoprotein expression induces growth arrest and apoptosis in human hepatocellular cancer cell

Alpha-fetoprotein: Past, present, and future

Alpha-fetoprotein (AFP) is a glycoprotein that plays an important role in immune regulation with critical involvement in early human development and maintaining the immune balance during pregnancy. Postfetal development, the regulatory mechanisms controlling AFP undergo a shift and AFP gene transcription is suppressed. Instead, these enhancers refocus their activity to maintain albumin gene transcription throughout adulthood. During the postnatal period, AFP expression can increase in the setting of hepatocyte injury, regeneration, and malignant transformation. It is the first oncoprotein discovered and is routinely used as part of a screening strategy for HCC. AFP has been shown to be a powerful prognostic biomarker, and multiple HCC prognosis models confirmed the independent prognostic utility of AFP. AFP is also a useful predictive biomarker for monitoring the treatment response of HCC. In addition to its role as a biomarker, AFP plays important roles in immune modulation to promote tumorigenesis and thus has been investigated as a therapeutic target in HCC. In this review article, we aim to provide an overview of AFP, encompassing the discovery, biological role, and utility as an HCC biomarker in combination with other biomarkers and how it impacts clinical practice and future direction.

Lysosomes Initiating and DNAzyme-Assisted Intracellular Signal Amplification Strategy for Quantification of Alpha-Fetoprotein in a Single Cell

Cellular trace proteins are critical for maintaining normal cell functions, with their quantitative analysis in individual cells aiding our understanding of the role of cell proteins in biological processes. This study proposes a strategy for the quantitative analysis of alpha-fetoprotein in single cells, utilizing a lysosome microenvironment initiation and a DNAzyme-assisted intracellular signal amplification technique based on electrophoretic separation. A nanoprobe targeting lysosomes was prepared, facilitating the intracellular signal amplification of alpha-fetoprotein. Following intracellular signal amplification, the levels of alpha-fetoprotein (AFP) in 20 HepG2 hepatoma cells and 20 normal HL-7702 hepatocytes were individually evaluated using microchip electrophoresis with laser-induced fluorescence detection (MCE-LIF). Results demonstrated overexpression of alpha-fetoprotein in hepatocellular carcinoma cells. This strategy represents a novel technique for single-cell protein analysis and holds significant potential as a powerful tool for such analyses.

Intracellular alpha-fetoprotein mitigates hepatocyte apoptosis and necroptosis by inhibiting endoplasmic reticulum stress

BACKGROUND

Endoplasmic reticulum (ER) stress contributes to the pathogenesis of chronic liver diseases, but how hepatocytes respond to ER stress has not been clarified. Alpha-fetoprotein (AFP) is secreted by hepatoma cells and elevated levels of serum AFP are associated with development of liver malignancies.

AIM

To investigate whether and how AFP could regulate ER stress and hepatocyte injury.

METHODS

The distribution of AFP and the degrees of ER stress in liver tissues and liver injury were characterized by histology, immunohistochemistry, and Western blot in biopsied human liver specimens, two mouse models of liver injury and a cellular model. The levels of AFP in sera and the supernatants of cultured cells were quantified by chemiluminescence.

RESULTS

High levels of intracellular AFP were detected in liver tissues, particularly in the necrotic areas, from patients with chronic liver diseases and mice after carbon tetrachloride (CCl₄) administration or induction of ER stress, but not from the controls. The induced intracellular AFP was accompanied by elevated activating transcription factor-6 (ATF6) expression and protein kinase R-like ER kinase (PERK) phosphorylation in mouse livers. ER stress induced AFP expression in LO2 cells and decreased their viability. ATF6, but not PERK, silencing mitigated the ER-stress-induced AFP expression in LO2 cells. Conversely, AFP silencing deteriorated the ER stress-mediated LO2 cell injury and CCl₄ administration-induced liver damages by increasing levels of cleaved caspase-3, the C/enhancer binding protein homologous protein expression, mixed lineage kinase domain-like pseudokinase and PERK phosphorylation, but decreasing ATF6 expression.

CONCLUSION

ER stress upregulated intra-hepatocyte AFP expression by activating ATF6 during the process of liver injury and intracellular AFP attenuated hepatocyte apoptosis and necroptosis by alleviating ER stress.

The Emerging Influences of Alpha-Fetoprotein in the Tumorigenesis and Progression of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide, and its mortality rate is the third-highest, after lung cancer and colorectal cancer. Currently, systematic targeted therapies for HCC mainly include multiple kinase inhibitors and immunotherapy. However, these drugs carry a black-box warning about the potential for inducing severe toxicity, and they do not significantly prolong the survival period of patients due to the highly heterogeneous characteristics of HCC etiology. In order to improve the prediction, effective treatment and prognosis of HCC, the tools and different biomarkers in clinical practices are recommended. Alpha-fetoprotein (AFP) is the earliest and the most widely used serum marker in the detection of HCC. Interestingly, serum AFP and cytoplasmic AFP show different, even opposite, roles in the cancer progression of HCC. This review focuses on biological characteristics, regulatory mechanisms for gene expression, emerging influences of AFP in HCC and its possible implications in HCC-targeted therapy.

Integrated analysis of the rhesus monkey liver transcriptome during development and human primary HCC AFP-related gene expression

Embryonic development and tumorigenesis have a certain degree of similarity. Alpha-fetoprotein (AFP), a protein related to embryonic development, is a well-known biomarker for the diagnosis and prognosis of hepatocellular carcinoma (HCC). In this study, we analyzed the differences in gene expression profiles and molecular mechanisms in human HCC tissues from patients in AFP^high (serum AFP level ≥ 25 ng/mL) and AFP^low (serum AFP level < 25 ng/mL) groups. The results indicated that AFP^high HCC has more malignant biological characteristics. Single-sample gene set enrichment analysis (ssGSEA) showed significantly higher levels of genes expressed in dendritic cells, neutrophils, and natural killer cells in the AFP^low group than in the AFP^high group. Then, we defined a rhesus monkey fetal liver developmental landscape and compared it to the HCC gene expression profile. The gene signatures of AFP^high HCC tissues were similar to those of early embryonic liver tissues. In this study, we comprehensively analyzed the rhesus monkey liver transcriptome during development and human primary HCC AFP-related gene expression profiles and clarified the function of AFP in the occurrence and development of HCC from the perspective of developmental biology, which might provide a new perspective on the pathogenesis of HCC.

Sorafenib and hepatocellular carcinoma: is alpha-fetoprotein a biomarker predictive of tumor biology and primary resistance?

Background: Alpha-fetoprotein (AFP) is the only biomarker with proven prognostic value in advanced hepatocellular carcinoma. Preliminary data indicate crosstalk between AFP and VEGF signaling. Methods: The authors looked at 69 patients with advanced hepatocellular carcinoma who were previously tested for VEGFR2 expression, had available baseline AFP serum concentrations and were treated with sorafenib within clinical trials. Results: Shorter progression-free survival and overall survival were associated with increased AFP level and elevated VEGFR2 staining. At multivariate analysis of AFP level was the only independent prognostic factor for progression-free survival and overall survival. Conclusion: The authors' study confirms the adverse prognostic role of elevated baseline AFP and also suggests a possible role of AFP in primary resistance to sorafenib therapy.

Role of Alpha-Fetoprotein in Hepatocellular Carcinoma Drug Resistance

Hepatocellular carcinoma (HCC) is a major type of primary liver cancer and a major cause of cancer-related deaths worldwide because of its high recurrence rate and poor prognosis. Surgical resection is currently the major treatment measure for patients in the early and middle stages of the disease. Because due to late diagnosis, most patients already miss the opportunity for surgery upon disease confirmation, conservative chemotherapy (drug treatment) remains an important method of comprehensive treatment for patients with middle- and late-stage liver cancer. However, multidrug resistance (MDR) in patients with HCC severely reduces the treatment effect and is an important obstacle to chemotherapeutic success. Alpha-fetoprotein (AFP) is an important biomarker for the diagnosis of HCC. The serum expression levels of AFP in many patients with HCC are increased, and a persistently increased AFP level is a risk factor for HCC progression. Many studies have indicated that AFP functions as an immune suppressor, and AFP can promote malignant transformation during HCC development and might be involved in the process of MDR in patients with liver cancer. This review describes drug resistance mechanisms during HCC drug treatment and reviews the relationship between the mechanism of AFP in HCC development and progression and HCC drug resistance.

AFP-Inhibiting Fragments for Drug Delivery: The Promise and Challenges of Targeting Therapeutics to Cancers

Alpha fetoprotein (AFP) plays a key role in stimulating the growth, metastasis and drug resistance of hepatocellular carcinoma (HCC). AFP is an important target molecule in the treatment of HCC. The application of AFP-derived peptides, AFP fragments and recombinant AFP (AFP-inhibiting fragments, AIFs) to inhibit the binding of AFP to intracellular proteins or its receptors is the basis of a new strategy for the treatment of HCC and other cancers. In addition, AIFs can be combined with drugs and delivery agents to target treatments to cancer. AIFs conjugated to anticancer drugs not only destroy cancer cells with these drugs but also activate immune cells to kill cancer cells. Furthermore, AIF delivery of drugs relieves immunosuppression and enhances chemotherapy effects. The synergism of immunotherapy and targeted chemotherapy is expected to play an important role in enhancing the treatment effect of patients with cancer. AIF delivery of drugs will be an available strategy for the targeted treatment of cancer in the future.

EPS364, a Novel Deep-Sea Bacterial Exopolysaccharide, Inhibits Liver Cancer Cell Growth and Adhesion

The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.

Alpha-Fetoprotein Binding Mucin and Scavenger Receptors: An Available Bio-Target for Treating Cancer

Alpha-fetoprotein (AFP) entrance into cancer cells is mediated by AFP receptors (AFPRs) and exerts malignant effects. Therefore, understanding the structure of AFPRs will facilitate the development of rational approaches for vaccine design, drug delivery, antagonizing immune suppression and diagnostic imaging to treat cancer effectively. Throughout the last three decades, the identification of universal receptors for AFP has failed due to their complex carbohydrate polymer structures. Here, we focused on the two types of binding proteins or receptors that may serve as AFPRs, namely, the A) mucin receptors family, and B) the scavenger family. We presented an informative review with detailed descriptions of the signal transduction, cross-talk, and interplay of various transcription factors which highlight the downstream events following AFP binding to mucin or scavenger receptors. We mainly explored the underlying mechanisms involved mucin or scavenger receptors that interact with AFP, provide more evidence to support these receptors as tumor AFPRs, and establish a theoretical basis for targeting therapy of cancer.

Spatial Lipidomics Reveals Anticancer Mechanisms of Bufalin in Combination with Cinobufagin in Tumor-Bearing Mice

Bufalin (BFL) and cinobufagin (CBF) are the principal bioactive constituents of Chansu, a widely used traditional Chinese medicine (TCM). The synergistic effects of potential active components are responsible for the bioactivities of TCM. Our results showed that the cotreatment with BFL and CBF confers superior anticancer efficacy compared to monotreatment. To reveal the underlying mechanisms of their cotreatment, an integrated method composed of mass spectrometry-based lipidomics and matrix-assisted laser desorption/ionization mass spectrometry imaging was used to delineate the responses of tumor-bearing mice treated with BFL and CBF individually or in combination. The cotreatment with BFL and CBF modulated the sphingolipid metabolism and glycerophospholipid metabolism, and subsequently led to mitochondria-driven apoptosis and systemic disruption of biomembranes in tumor cells. Furthermore, we found that the disturbed lipid markers were mainly located in the non-necrotic tumor areas, the essential parts for the formation of solid tumor framework. Together, our findings revealed what occurred in tumor in response to the treatment of BFL and CBF, from lipids to enzymes, and thus provide insights into the critical role of lipid reprogramming in the satisfactory anticancer effect of BFL in combination with CBF.

An Albumin-Bilirubin (ALBI) Grade-based Prognostic Model For Patients With Hepatocellular Carcinoma Within Milan Criteria

OBJECTIVE

The Milan criteria are recommended as the major reference for liver transplantation in patients with small hepatocellular carcinoma (HCC). However, alternative anticancer treatments are often utilized due to severe donor organ shortage. This study aimed to develop and validate an albumin-bilirubin (ALBI) grade-based prognostic model to stratify survival in patients within Milan criteria undergoing nontransplant therapy.

PATIENTS AND METHODS

A total of 1655 patients were assigned into the derivation and validation cohort according to treatment modalities. Multivariate analysis was used to identify independent predictors of survival in the derivation cohort. An ALBI-based model was evaluated in the validation cohort.

RESULTS

In the Cox multivariate model, age 65 years or older (hazard ratio [HR]=1.576, P<0.001), serum α-fetoprotein (AFP) level >100 ng/mL (HR=1.671, P<0.001), ascites (HR=1.808, P<0.001), performance status 1 to 4 (HR=1.738, P<0.001), ALBI grade 2 (HR=1.827, P<0.001), and ALBI grade 3 (HR=3.589, P<0.001) were independent predictors of poor survival in the derivation cohort. An ALBI-based prognostic model with a total of 0 to 6 points was derived with the sum of 5 variables: 1 point each for age 65 years or older, AFP >100 ng/mL, presence of ascites, performance status 1 to 4, and ALBI grade 2, and 2 points for ALBI grade 3. This model can accurately predict long-term outcome in the validation cohort (P<0.001) and discriminate survival in patients stratified by curative and noncurative treatments (both P<0.001).

CONCLUSION

The proposed ALBI grade-based model is feasible in predicting survival in HCC patients within the Milan criteria, and helps identify high-risk patients who need timely liver transplantation.

More Than a Tumor Marker…A Potential Role for Alpha-Feto Protein in Inflammatory Bowel Disease

BACKGROUND

Human alpha-fetoprotein (hAFP) is a glycoprotein derived from the gut entoderm and expressed sequentially by cells of the yolk sac, fetal liver, and gastrointestinal tract. By adulthood, serum levels of alpha-fetoprotein (AFP) are undetectable in healthy, nonpregnant adults. Despite the clinical utilities of AFP monitoring in pregnancy and malignancy, much remains to be determined regarding its potential physiological functions.

METHODS

We focused on literature related to AFP's immunoregulatory role and its ability to modulate disease activity both in animal models of autoimmune disorders and in human clinical studies.

RESULTS

Evidence suggests that AFP plays an important role in immunoregulation by inducing T-cell suppressor activity, downregulating dendritic-like cell antigen expression, and impairing the function of macrophages. Studies evaluating AFP and its effects in rodent models of autoimmune diseases have shown that AFP is associated with downregulation of inflammation. Observations in studies of pregnant patients with immune-mediated inflammatory diseases have also described potential correlations between AFP expression and disease activity during different stages of pregnancy and postpartum.

CONCLUSIONS

We propose further prospective evaluations of AFP expression during pregnancy in inflammatory bowel disease patients to further correlate with disease activity and consider the potential of AFP as a novel therapeutic agent.

Activated Wnt signaling promotes growth and progression of AFP-producing gastric cancer in preclinical models

Background

Characterized by elevated AFP levels in serum, AFP-producing gastric cancer (APGC) is a very special type of gastric cancer (GC) that is difficult to treat and has poor prognosis. However, little is known about the role of AFP in GC, which was investigated in this study with in vitro and in vivo experiments.

Methods

APGC cells were established with lentivirus infection and validated by PCR assay and ELISA in HCG27 and AGS cells. Cell growth, migration, and invasion were determined by CCK8, transwell assays, and animal experiments. RNA sequencing, Western blot, dual-luciferase-reporter assays, and RNA interference were employed to understand mechanisms underlying AFP activity, followed by therapeutic investigations for APGC.

Results

APGC cells featured significantly increased AFP levels in cellular supernatants. AFP potentiated growth and aggression in GC cell lines and their derived xenografts. Wnt-signaling activation was responsible for AFP function, indicated by decreased Axin 1 and pGSK3β, followed by cascade activation of β-catenin, downstream transcription factors TCF1/TCF7, and the target gene – c-Myc. Wnt-signaling blockade by Axin 1 rescue or pathway inhibitor XAV939 reversed AFP function, suggesting the potential therapeutic value of APGC.

Conclusion

AFP played a critical role in APGC through activating Wnt signaling, and targeting Wnt pathways might be a promising strategy against APGC.

Metastasis in patients with hepatocellular carcinoma: Prevalence, determinants, prognostic impact and ability to improve the Barcelona Clinic Liver Cancer system

BACKGROUND & AIM

Patients with hepatocellular carcinoma and metastasis are classified as advanced or terminal stage by the Barcelona Clinic Liver Cancer system. This study investigates the prevalence, determinants, and prognostic effect of metastasis and its ability to improve the Barcelona Clinic Liver Cancer system.

METHODS

A total of 3414 patients were enrolled. The Kaplan-Meier and Cox regression methods were used to determine survival predictors. Akaike information criterion was used to compare the prognostic performance of staging systems.

RESULTS

There were 357 (10%) patients having extrahepatic metastasis at the time of diagnosis. Metastases were associated with old age, alcoholism, hepatitis B, poorer liver function, higher α-foetoprotein level and larger tumour burden (all P < .05). Vascular invasion was associated with metastasis regardless of total tumour volume, and higher α-foetoprotein level and multiple tumours were associated with metastasis in patients with smaller tumour volume (all P < .05). Patients with both vascular invasion and metastasis had significantly worse outcome compared to patients with either vascular invasion or metastasis (P < .05). In the Cox proportional model, the co-existence of vascular invasion and metastasis was an independent predictor of decreased survival (P < .05). Re-allocating 181 Barcelona Clinic Liver Cancer stage C patients with both vascular invasion and metastasis into stage D was associated with lower Akaike information criterion, indicating enhanced prognostic power of the Barcelona Clinic Liver Cancer.

CONCLUSIONS

Metastasis is not uncommon, and is strongly associated with tumoural factors and poor long-term survival in hepatocellular carcinoma. Modification of the Barcelona Clinic Liver Cancer system based on vascular invasion and metastasis may further improve its predictive accuracy in advanced stage patients.

HBx drives alpha fetoprotein expression to promote initiation of liver cancer stem cells through activating PI3K/AKT signal pathway

Hepatitis B virus (HBV)-X protein (HBx) plays critical role in inducing the malignant transformation of liver cells. Alpha fetoprotein (AFP) expression is closely related to hepatocarcinogenesis. We report that Oct4, Klf4, Sox2 and c-myc expression positively associated with AFP(+)/HBV(+) hepatocellular carcinoma(HCC) tissues, and the expression of the stemness markers CD44, CD133 and EpCAM was significantly higher in AFP(+)/HBV(+) HCC tissues compared to normal liver tissues or AFP (-)/HBV(-) HCC tissues. AFP expression turned on prior to expression of Oct4, Klf4, Sox2 and c-myc, and the stemness markers CD44, CD133 and EpCAM in the normal human liver L-02 cell line or CHL cell lines upon transfection with MCV-HBx vectors. Stem-like cells generated more tumour colonies compared to primary cells, and xenografts induced tumourigenesis in nude mice. Expression of reprogramming-related proteins was significantly enhanced in HLE cells while transfected with pcDNA3.1-afp vectors. The specific PI3K inhibitor Ly294002 inhibited the effects of pcDNA3.1-afp vectors. AFP-siRNA vectors were able to inhibit tumour colony formation and reprogramming-related gene expression. Altogether, HBx stimulates AFP expression to induce natural reprogramming of liver cells, and AFP plays a critical role in promoting the initiation of HCC progenitor/stem cells. AFP may be a potential novel biotarget for combating HBV-induced hepatocarcinogenesis.

Alpha fetoprotein antagonizes apoptosis induced by paclitaxel in hepatoma cells in vitro

Hepatocellular carcinoma (HCC) cell resistance to the effects of paclitaxel has not been adequately addressed. In this study, we found that paclitaxel significantly inhibited the viability of HLE, Bel 7402 and L-02 cells in a dose- and time-dependent manner. HLE cells and L-02 cells resisted the cytotoxicity of paclitaxel when transfected with pcDNA3.1-afp vectors. However, Bel 7402 cell sensitivity to paclitaxel was increased when transfected with alpha fetoprotein (AFP)-siRNA. Bel 7402 cell resistance to paclitaxel was associated with the expression of the “stemness” markers CD44 and CD133. Paclitaxel significantly inhibited growth and promoted apoptosis in HLE cells and L-02 cells by inducing fragmentation of caspase-3 and inhibiting the expression of Ras and Survivin, but pcDNA3.1-afp vectors prevented these effects. However, paclitaxel could not significantly promote the cleavage of caspase-3 or suppress the expression of Ras and Survivin in Bel 7402 cells. Silenced expression of AFP may be synergistic with paclitaxel to restrain proliferation and induce apoptosis, enhance cleavage of caspase-3, and suppress the expression of Ras and Survivin. Taken together, AFP may be an important molecule acting against paclitaxel-inhibited proliferation and induced apoptosis in HCC cells via repressing the activity of caspase-3 and stimulating the expression of Ras and Survivin. Targeted inhibition of AFP expression after treatment with paclitaxel is an available strategy for the therapy of patients with HCC.

Hepatitis B Virus X Protein Driven Alpha Fetoprotein Expression to Promote Malignant Behaviors of Normal Liver Cells and Hepatoma Cells

Background: The infection of Hepatitis B virus (HBV) is closely associated with the development of hepatocellular carcinoma(HCC), HBV-X protein(HBx) is able to induce expression of alpha-fetoprotein(AFP) in normal liver cells, and AFP harbors a function to promote malignant transformation of normal liver cells, but the role AFP playing in malignant behaviors of HCC cells is still unclear.

Methods: Fifty-six liver tissue samples were collected from the clinical patients through hepatectomy(include normal liver tissues, HBV-related hepatitis liver tissues and HBV-related HCC tissues), and diagnosis of these tissues by pathology section, expression of AFP, Ras and CXCR4 were evidenced by immunohisochemical staining and Western blotting; The proliferation of human normal liver cells line L-02 cells and human hepatoma cells line, HLE cells(non AFP-producing) were performed by MTT method; Repaired capacity of L-02 and HLE cells were compared by wound healing assay; Migration and invasion of these cells were analyzed by Transwell chamber assay; HBx expressed vectors(pcDNA3.1-HBx) were constructed and transfected into L-02 and HLE cells, effects of pcDNA3.1-HBx on the malignant behaviors were also detected by MTT, Transwell chamber assay and the expression of AFP, Ras and CXCR4 were evidenced by Western blotting.

Results: we found that expression of AFP, Ras and CXCR4 in HBV-related HCC and lymph nodes metastasis tissues were significantly elevated compared with HBV-related HCC, non metastasis tissues and HBV-related hepatitis tissues; Expression of AFP, Ras and CXCR4 in HBV-related hepatitis tissues were significantly enhanced compared with normal liver tissues; The growth ratio, migratory and invasive ability, expression of AFP, Ras and CXCR4 of the cells were outstanding promoted while L-02 and HLE cells were transfected with pcDNA3.1-HBx vectors. The proliferation ratio, migration and invasion ability, and expression of Ras and CXCR4 were significantly inhibited while L-02-X and HLE-X cells(stably transfected with pcDNA3.1-HBx) were silenced AFP expression by AFP-siRNA.

Conclusions: HBx through stimulating expression of AFP to promote malignant behaviors of human normal liver cells and HCC cells; AFP maybe used as a novel biotarget for therapeutics of HCC patients.

Prognostic Significance of Preoperative Serum Alpha- fetoprotein in Hepatocellular Carcinoma and Correlation with Clinicopathological Factors: a Single-center Experience from China

OBJECTIVES

To investigate the prognosis significance of preoperative serum alpha-fetoprotein (AFP) and the correlation with clinicopathological factors of hepatocellular carcinoma (HCC) patients who underwent hepatectomy.

MATERIALS AND METHODS

Clinicopathological data of retrospective analysis were collected for 251 HCC patients undergoing hepatectomy in this study. According to preoperative AFP level, patients were categorized into AFP-negative (0-20 ng/mL) and AFP-positive (>20 ng/mL) groups for Kaplan-Meier analysis and Cox proportional hazard regression modeling.

RESULTS

The results demonstrated that increased AFP was associated with longer prothrombin time (PTs), liver capsule invasion, low grade differentiation, and late Barcelona Clinic Liver Center (BCLC) stage. Moreover, the female patients had a greater prevalence of increased preoperative AFP than male patients [284.8 (3.975-3167.5) vs (3.653-140.65); Z-2.895, p=0.004]. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 78.1, 57.5, and 40.6 % in the AFP-negative group and 61.8, 37.7, and 31.4 %, respectively, in the AFP-positive group (log-rank test 8.312, p=0.004). The 1-, 3-, and 5-year overall survival (OS) rates were 94.4, 83.8, and 62.3% in the AFP-negative group and 87.2, 60.0, and 36.7%, respectively, in the AFP-positive group. The difference was statistically significant (log-rank test, 16.884, p=0.000). Cox proportional-hazards model identified preoperative AFP to be an independent prognostic predictor of overall survival.

CONCLUSIONS

Preoperative serum AFP is an independent predictor of prognosis among HCC patients following surgical resection. Female patients have a higher preoperative AFP than their male counterparts.

Alpha fetoprotein plays a critical role in promoting metastasis of hepatocellular carcinoma cells

A high level of serum alpha fetoprotein (AFP) is positively associated with human hepatocellular carcinoma (HCC) carcinogenesis and metastasis; however, the function of AFP in HCC metastasis is unknown. This study has explored the effects of AFP on regulating metastatic and invasive capacity of human HCC cells. Forty-seven clinical patients' liver samples were collected and diagnosed; HCC cells line, Bel 7402 cells (AFP-producing) and liver cancer cell line cells (non-AFP-producing) were selected to analyse the role of AFP in the metastasis of HCC cells. The results indicated that high serum concentration of AFP was positively correlated with HCC intrahepatic, lymph nodes and lung metastasis. Repressed expression of AFP significantly inhibited the capability of migration and invasion of Bel 7402 cells, expression of keratin 19 (K19), epithelial cell adhesion molecule (EpCAM), matrix metalloproteinase 2/9 (MMP2/9) and CXC chemokine receptor 4 (CXCR4) were also down-regulated in Bel 7402 cells; migration and invasion, expression of K19, EpCAM, MMP2/9 and CXCR4 were significantly enhanced when HLE cells were transfected with AFP-expressed vector. The results demonstrated that AFP plays a critical role in promoting metastasis of HCC; AFP promoted HCC cell invasion and metastasis via up-regulating expression of metastasis-related proteins. Thus, AFP may be used as a novel therapeutic target for treating HCC patients.

Using serum α-fetoprotein for prognostic prediction in patients with hepatocellular carcinoma: what is the most optimal cutoff?

Background and Aims

The prognostic ability of α-fetoprotein (AFP) for patients with hepatocellular carcinoma (HCC) was examined by using different cutoff values. The optimal AFP cutoff level is still unclear.

Methods

A total of 2579 HCC patients were consecutively enrolled in Taiwan, where hepatitis B is the major etiology of chronic liver disease. Four frequently used AFP cutoff levels, 20, 200, 400, 1000 ng/mL, were investigated. One-to-one matched pairs between patients having AFP higher and lower than the cutoffs were selected by using the propensity model. The adjusted hazard ratios of survival difference were calculated with Cox proportional hazards model.

Results

Patients with a higher AFP level were associated with more severe cirrhosis, more frequent vascular invasion, higher tumor burden and poorer performance status (all p<0.0001). In the propensity model, 4 groups of paired patients were selected, and there was no difference found in the comparison of baseline characteristics (all p>0.05). Patients with AFP <20 ng/mL had significantly better long-term survival than patients with AFP ≧20 ng/mL (p<0.0001), and patients with AFP <400 ng/mL had significantly better overall outcome than patients with AFP ≧400 ng/mL (p = 0.0186). There was no difference of long-term survival between patients divided by AFP levels of 200 and 1000 ng/mL. The adjusted hazard ratios of AFP ≧20 ng/mL and AFP ≧400 ng/mL were 1.545 and 1.471 (95% confidence interval: 1.3–1.838 and 1.178–1.837), respectively.

Conclusions

This study shows the independently predictive ability of baseline serum AFP level in HCC patients. AFP levels of 20 and 400 ng/mL are considered feasible cutoffs to predict long-term outcome in unselected HCC patients.

Pantoprazole inhibits cancer cell proliferation in mice with diethylnitrosamine and carbon tetrachloride-induced hepatoma

AIM: To investigate the effect of pantoprazole on the proliferation of cancer cells of mice with hepatoma induced by diethylnitrosamine (DEN) plus carbon tetrachloride.

METHODS: Seventy-eight C57 mice were treated with DEN and carbon tetrachloride (CCl₄) for 9 wk and then randomly divided into three groups: a model group, low- (40 mg/kg) and high-dose (80 mg/kg) pantoprazole groups. Twelve normal C57 mice were used as controls. The two pantoprazole groups were administrated pantoprazole for 25 wk by intraperitoneal injection, and the mice were then sacrificed for collecting normal liver tissues, hepatoma tissues and hepatoma-adjacent tissues. All these tissues were prepared for pathological observation by HE staining. Blood levels of alanine transaminase (ALT), aspartate aminotransferase (AST), urea, and creatinine (Cr) were assayed. The mRNA levels of α-fetoprotein (AFP), Ki67, and proliferating cell nuclear antigen (PCNA) were quantified by real-time PCR, and the protein levels of Ki67 and PCNA were tested by Western blot.

RESULTS: Hepatoma was successfully induced in all mice treated with DEN and carbon tetrachloride, and 21% of the mice were dead. Gross examination of liver tissues showed that the livers in the model group were larger and had more heterogeneous nodules than those in the pantoprazole groups. Pathological analysis showed a lower incidence of dysplasia after administration of pantoprazole. Compared with normal controls, the levels of ALT and AST were increased in the model and pantoprazole groups, and these biological indexes in the pantoprazole groups were significantly lower than those in the model group (P < 0.05). The mRNA levels of AFP, Ki67 and PCNA in the model group and pantoprazole groups were significantly higher than those in normal controls (P < 0.05, F = 7.94; P < 0.05, F = 15.62; P < 0.01, F = 45.58), and pantoprazole decreased Ki67 and PCNA mRNA levels significantly compared with the model group (P < 0.05, F = 5.89, P < 0.05, F = 10.34). The expression of Ki67 and PCNA proteins was increased by treatment with DEN and carbon tetrachloride (P < 0.05, F = 20.41; P < 0.05, F = 20.31) but was decreased by pantoprazole treatment (P < 0.05, F = 16.47; P < 0.05, F = 12.38).

CONCLUSION: Pantoprazole can inhibit the growth of murine hepatoma by inhibiting cancer cell proliferation.

Hsa-miR-1 downregulates long non-coding RNA urothelial cancer associated 1 in bladder cancer

MicroRNAs (miRNAs) are known to mainly target protein-coding genes at post-transcriptional level, resulting in mRNA destabilization and/or translational repression. Long non-coding RNAs (lncRNAs) are emerging as a novel set of targets for miRNAs. Here, we report that downregulated hsa-miR-1 and upregulated lncRNA urothelial cancer associated 1 (UCA1) were inversely expressed in bladder cancer. Hsa-miR-1 decreased the expression of UCA1 in bladder cancer cells in an Ago2-slicer-dependent manner. The binding site between UCA1 and hsa-miR-1 was confirmed. Overexpression of hsa-miR-1 inhibited bladder cancer cell growth, induced apoptosis, and decreased cell motility. Knockdown of UCA1 expression phenocopied the effects of upregulation of hsa-miR-1. Transfection of UCA1 expression vector partly reversed the changes caused by transfection of pre-miR-1 plasmids. This study provides evidence for hsa-miR-1 to play tumor suppressive roles via downregulating lncRNA UCA1 in bladder cancer, which may have potential therapeutic significance.

Effects of ephrinB2 gene siRNA on the biological behavior of human colorectal cancer cells

Colorectal cancer (CRC) is a common gastrointestinal malignancy worldwide and is a lethal and aggressive malignancy with a dismal prognosis. EphrinB2 is a membrane-bound ligand and has an intracellular domain that also possesses an intrinsic signaling capacity called 'reverse signaling'. In the present study, CRC cell lines were screened for high expression of ephrinB2. Small interfering RNA (siRNA) knockdown of ephrinB2 was performed in human SW480 CRC cells. The levels of expression of ephrinB2, VEGF, CD105 and matrix metalloproteinase 9 (MMP9) protein were measured by western blotting, and messenger RNA (mRNA) levels were measured using real-time PCR. Apoptosis and cell cycle distribution were determined using flow cytometry. Cell proliferation was measured by a methyl thiazole tetrazolium (MTT) test and a scratch healing experiment was used to measure the extent of cell migration. A Transwell assay was used to detect the extent of cell invasion. The results showed that RNA interference (RNAi) of ephrinB2 effectively silenced the ephrinB2 gene at both the mRNA and protein levels in SW480 cells and inhibited the proliferation, invasion, migration and angiogenesis and induced apoptosis in SW480 cells. These effects may be attributed to VEGF and MMP9 regulation.

Prognostic value of serum γ-glutamyl transferase in unresectable hepatocellular carcinoma patients treated with transcatheter arterial chemoembolization combined with conformal radiotherapy

The detection of γ-glutamyl transferase (GGT) has previously been reported to be useful in the diagnosis in hepatocellular carcinoma (HCC). The aim of the present study was to investigate the baseline serum GGT levels in patients with intermediate HCC (Barcelona Clinic Liver Cancer stage B) following treatment with transcatheter arterial chemoembolization (TACE) combined with three-dimensional conformal radiotherapy (3DCRT). A total of 154 intermediate HCC patients with Child-Pugh grade A were retrospectively investigated. Receiver operating characteristic (ROC) analysis was used to determine the optimal threshold for the GGT serum levels, and univariate and multivariate analyses were used to establish the prognostic factors. The median overall survival (OS) time was 24.3 months. The optimal threshold for GGT was 85 U/L (sensitivity, 75.13%; specificity, 69.81%; and area under the ROC curve, 0.763). The one-, three- and five-year OS rates were 79.9, 49.7 and 17.2%, respectively, for patients with low GGT levels (≤85 U/l) and 52.3, 22.1 and 8.5%, respectively, for patients with high GGT levels (>85 U/l) (P=0.007). The results indicated that the serum GGT level was an independent prognostic factor (hazard ratio=2.32; P=0.007) for OS. Furthermore, in subgroups stratified according to serum α-fetoprotein, gross tumor volume and radiation dose, serum GGT was also found to correlate with OS (P<0.05). Therefore, the baseline GGT level may be a significant prognostic factor for intermediate HCC patients with Child-Pugh grade A following TACE combined with 3DCRT.

Effect of pre- and post-treatment α-fetoprotein levels and tumor size on survival of patients with hepatocellular carcinoma treated by resection, transarterial chemoembolization or radiofrequency ablation: a retrospective study

Background

We evaluated treatment modalities and survival in patients with hepatocellular carcinoma (HCC), by pre-treatment and 3-month post-treatment serum alpha-fetoprotein (AFP) levels and pre-treatment tumor diameters.

Methods

We retrospectively reviewed 57 patients treated for HCC in our department from January 2002 to December 2012, including their sex, type of hepatitis, Child class, pre-treatment tumor size, pre-treatment levels of albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (GGT), red blood cells, hemoglobin, and total bilirubin, pre- and 3-month post-treatment serum AFP, and treatment modality (transarterial chemoembolization, resection or radiofrequency ablation). Survival was analyzed at 1, 3, and 5 years after treatment.

Results

The 57 patients included 44 men and 13 women, of whom 44 had hepatitis C virus (HCV) infection, 3 had hepatitis B virus (HBV) infection, 3 had both HBV and HCV infection, 1 had both HBV and hepatitis D virus infection, and 3 had alcohol-related liver cirrhosis. Both pre- and post-treatment serum AFP levels significantly correlated with recurrent tumor size (P < 0.05 for both). Pre-treatment tumor size did not correlate with recurrent tumor size. Patients who underwent hepatic resection survived significantly longer than those who underwent transarterial chemoembolization or radiofrequency ablation (P < 0.05).

Conclusions

Serum AFP level is useful in diagnosing tumor recurrence and predicting prognosis in HCC patients treated by hepatic resection, transarterial chemoembolization, and radiofrequency ablation. Hepatic resection remains the treatment of choice for HCC in suitable patients.

Suppression of toll-like receptor 2 expression inhibits the bioactivity of human hepatocellular carcinoma

Toll-like receptor (TLR) 2 signaling is regarded as one of the mechanisms of chronic inflammation, but it can also mediate tumor cell immune escape and tumor progression. However, the role of TLR2 in the progression of human hepatocellular carcinoma (HCC) remains unclear. The objective of the study was to examine the effect of TLR2 on the bioactivity of HCC cell lines, HepG2 and BEL-7402, and the relationship between high mobility group box1 (HMGB1) and TLR2. The expression of TLR2 and nuclear factor-kappaB/P65 (NF-κB/P65) in HepG2 and BEL-7402 was assayed by Western blot. Cells were transfected with specific small interfering RNAs of TLR2 (TLR2-siRNAs), then TLR2-siRNA-transfected cells were treated with recombinant HMGB1 (rHMGB1). Apoptosis was determined by flow cytometry. Results showed that TLR2 was expressed in HepG2 and BEL-7402 cells. The ability of proliferation, invasion, and migration in siRNA group was lower than that in blank group, and the apoptosis ratio was higher than that in blank group, respectively. NF-κB/P65 expression was declined in contrast with blank group. Downregulation of TLR2 by siRNA resulted in a significant inhibition of proliferation, invasion, migration, and NF-κB/P65 expression, and elevated apoptotic ratio. Conversely, rHMGB1 promoted proliferation, invasion, and migration, induced NF-κB/P65 expression, and inhibited cells apoptosis. Furthermore, downregulation of TLR2 weakened the role of rHMGB1. This study suggests TLR2 and HMGB1 are important targets for therapeutic intervention of HCC.

Benzyl isothiocyanate induces apoptosis of hepatocarcinoma cells

AIM: To investigate the influence of benzyl isothiocyanate (BITC) on apoptosis of hepatoma carcinoma cell lines HLE and Bel-7402 in vitro, and to explore the possible mechanism involved.

METHODS: After HLE and Bel-7402 cells were treated with an optimal concentration of BITC for 24 h, cell proliferation was tested by MTT assay, the morphology of apoptotic hepatoma cells was observed after DAPI staining, the enzymatic activity of caspase 3 was assayed using Caspase3 Activity Assay Kit, and expression of caspase 8, caspase 3 and cell cycle related protein cyclin D1 were detected by Western blot.

RESULTS: MTT analysis showed that BITC had an obvious inhibitory effect on the proliferation of hepatoma cells. The growth rates of HLE and Bel-7402 cells treated with 40 µmol/L BITC were 71.56% and 78.09% (P < 0.05 vs control groups), respectively, and the growth rates of HLE and Bel-7402 cells treated with 80 µmol/BITC were 32.91% and 53.06% (P < 0.01 vs control groups), respectively. Hepatoma cells treated with BITC tended to showed characteristic morphological changes of apoptosis. BITC treatment elevated the activity of caspase 3 in hepatoma cells, stimulated the expression of caspase 3 and caspase 8, but inhibited cyclin D1 expression.

CONCLUSION: BITC induces apoptosis of hepatoma cells possibly by activating the caspase signal pathway and inhibiting cell cycle progression.

Benzylidene-indolinones are effective as multi-targeted kinase inhibitor therapeutics against hepatocellular carcinoma

Effective pharmacological intervention of advanced hepatocellular carcinoma (HCC) is currently lacking. Despite the use of tyrosine kinase inhibitors (TKIs) for the targeted therapy of several malignancies, no agent has been developed to specifically interfere with the oncogenic tyrosine kinase signaling aberrations found in HCC. Therefore, we adopted an orthogonal biological phenotypic screening approach to uncover candidate compounds: based on a potent cytotoxicity toward HCC-derived cell lines, and minimal toxicity toward normal liver cells. Given the success of indolinone as a chemical scaffold in deriving potent multi-kinase inhibitors (e.g. sunitinib), we screened a group of newly synthesized benzylidene-indolinones. Among the candidates, E/Z 6-Chloro-3-(3-trifluoromethyl-benzyliden)-1,3-dihydroindol-2-one (compound 47) exhibited potent anti-proliferative, anti-migratory, pro-apoptotic properties and good safety profile as compared to known multi-targeted tyrosine kinase inhibitors sunitinib and sorafenib. Additionally, an accompanying suppression of alpha-fetoprotein (AFP) transcription, an HCC tumor marker, implies a favorable selectivity and efficacy on HCC. The in vivo efficacy was demonstrated in an HCC xenograft where 47 was administered once weekly (60 mg/kg) and suppressed tumor burden to the same extent as sorafenib (30 mg/kg daily). A receptor tyrosine kinase (RTK) array study revealed promising inhibition of multiple tyrosine kinases such as IGF-1R, Tyro3 and EphA2 phosphorylation. Gene silencing of these targets ameliorated the cytotoxic potential of 47 on the HuH7 cell line, thereby implicating their contribution to the tumorigenicity of HCC. Hence, 47 exhibits potent anti-cancer effects on HCC cell lines, and is a suitable lead for developing multi-targeted kinase inhibitors of relevance to HCC.

Alpha fetoprotein can induce malignant transformation of liver cells and be used as a therapeutic target for hepatocellular carcinoma

Alpha-fetoprotein (AFP) is associated with the development of hepatocellular carcinoma (HCC) and widely used as a golden tumor marker for diagnosing HCC since the AFP gene is activated in the early stage of malignant transformation of liver cells. However, the molecular mechanisms responsible for the role of AFP in hepatocarcinogenesis remain poorly understood. Recently, we found that hepatitis B virus (HBV) preferentially induces the expression of AFP when triggering malignant transformation of hepatocytes, and AFP activates phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT) signaling by inhibiting the activity of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Our results also indicated that AFP not only impedes all-trans retinoid acid receptor-β (RAR-β) regulated expression of target genes, but also blocks the transduction of apoptotic signaling by suppressing the activity of Caspase3. Inhibited expression of AFP is able to augment HCC sensitivity to tumor necrosis factor-related apoptosis-induced ligand (TRAIL) and all-trans retinoid acid. These data indicate that AFP can drive the malignant transformation of liver cells and antagonize apoptosis induced by agents for HCC. Taken together, these findings suggest that AFP may drive the malignant transformation of liver cells and can be used as a target for therapy of HCC.

Identification of novel serum biomarkers of hepatocellular carcinoma using glycomic analysis

The altered N-glycosylation of glycoproteins has been suggested to play an important role in the behavior of malignant cells. Using glycomics technology, we attempted to determine the specific and detailed N-glycan profile for hepatocellular carcinoma (HCC) and investigate the prognostic capabilities. From 1999 to 2011, 369 patients underwent primary curative hepatectomy in our facility and were followed up for a median of 60.7 months. As normal controls, 26 living Japanese related liver transplantation donors were selected not infected by hepatitis B and C virus. Their mean age was 40.0 and 15 (57.7%) were male. We used a glycoblotting method to purify N-glycans from preoperative blood samples from this cohort (10 μL serum) which were then identified and quantified using mass spectrometry (MS). Correlations between the N-glycan levels and the clinicopathologic characteristics and outcomes for these patients were evaluated. Our analysis of the relative areas of all the sugar peaks identified by MS, totaling 67 N-glycans, revealed that a proportion had higher relative areas in the HCC cases compared with the normal controls. Fourteen of these molecules had an area under the curve of greater than 0.80. Analysis of the correlation between these 14 N-glycans and surgical outcomes by univariate and multivariate analysis identified G2890 (m/z value, 2890.052) as a significant recurrence factor and G3560 (m/z value, 3560.295) as a significant prognostic factor. G2890 and G3560 were found to be strongly correlated with tumor number, size, and vascular invasion.

CONCLUSION

Quantitative glycoblotting based on whole serum N-glycan profiling is an effective approach to screening for new biomarkers. The G2890 and G3560 N-glycans determined by tumor glycomics appear to be promising biomarkers for malignant behavior in HCCs. (HEPATOLOGY 2013;).

Natural Bcl-2 inhibitor (-)- gossypol induces protective autophagy via reactive oxygen species-high mobility group box 1 pathway in Burkitt lymphoma

(-)- Gossypol, a natural inhibitor of anti-apoptotic Bcl-2 proteins, has presented an effective anti-tumor activity in numerous preclinical trials. More and more evidence in vivo and in vitro validates that (-)- gossypol can dramatically suppress cell proliferation and induce cell death in hematological malignancies. However, the detailed mechanisms are not well known. In the present study, we showed that treatment with (-)- gossypol stimulated reactive oxygen species (ROS) generation and induced autophagy in Burkitt lymphoma cells. Antioxidant N-acetyl-cysteine (NAC) pretreatment attenuated (-)- gossypol-induced autophagy. Furthermore, (-)- gossypol treatment increased the translocation of high mobility group box 1 (HMGB1) from nuclei to cytoplasm, which can be suppressed by NAC pretreatment. NAC pretreatment also dramatically enhanced (-)- gossypol-induced apoptosis and total cell death. These results indicate that (-)- gossypol induces a protective autophagy in Burkitt lymphoma cells, partly due to ROS induction and cytosolic translocation of HMGB1. Antioxidants may serve as potent chemosensitizers to enhance cell death through blocking (-)- gossypol-induced autophagy.

Risk factors of poor prognosis and portal vein tumor thrombosis after curative resection of solitary hepatocellular carcinoma

BACKGROUND

Predictors of poor prognosis of solitary hepatocellular carcinoma (SHCC), a subgroup encompassing most patients with the malignancy, are still controversial. Hence, risk factors for portal vein tumor thrombosis (PVTT) in SHCC are obscure. The present study was designed to address this issue.

METHOD

Clinicopathological and follow-up data for 156 consecutive patients with SHCC following curative hepatic resection were analyzed using uni- and multi-variate analyses.

RESULTS

Univariate analysis showed that PVTT, tumor-node-metastasis (TNM) stage, Edmondson-Steiner grade and preoperative serum alpha-fetoprotein (AFP) level were associated with the overall and disease-free survival, whereas tumor size only influenced the overall survival. In multivariate Cox regression tests, Edmondson-Steiner grade and TNM stage were independent prognostic markers for both overall and disease-free survival. In addition, the Chi-square test showed that AFP level and Edmondson-Steiner grade were correlated with PVTT. Among them, only Edmondson-Steiner grade was shown to be of independent significance for PVTT in multi-variate logistic regression analysis. Additionally, AFP, the sole preoperative factor for PVTT, was not adequately sensitive and specific.

CONCLUSIONS

Factors relating to post-surgical prognosis and PVTT in SHCC are all tumor-related. Of these, Edmondson-Steiner grade and TNM stage might be of particular importance in survival analysis. In addition, accurate prediction of PVTT by clinicopathological parameters before surgery remains difficult.

Transient therapy-related surge in serum tumor biomarkers: characterizing behavior and postulating its biologic role

A phenomenon of serum tumor biomarker surge or flare that ensues shortly after initiating cancer therapy and that may precede the actual therapeutic response-related decline is poorly understood and remains under-appreciated. However, it may have a significant clinical implication as it could be misinterpreted in clinical practice as therapeutic failure and lead to a premature discontinuation of potentially effective therapy. Therefore, in the present study, attempts have been made to understand the behavior of this phenomenon with respect to a reported median incidence, duration, and its relationship to clinical response. The results of these analyses suggest a significantly lower incidence of this phenomenon with carcinoembryonic antigen (CEA) as determined in colorectal cancer and prostate specific antigen (PSA) in prostate cancer as compared to the other biomarkers studied (p=0.006). Furthermore, regardless of the type of biomarker or the extent of its incidence, a therapy-related initial surge appears to correlate with eventual response to therapy. Although, the biologic significance of this phenomenon is currently elusive, two distinct hypothesis-generating cases with CEA and alpha-fetoprotein (AFP) are presented that, if supported by further research, would provide insights into the role of a biomarker surge in overall tumor growth control by cancer therapy.

Relationship of α-fetoprotein levels and development of hepatocellular carcinoma in hepatitis C patients with liver cirrhosis

α-fetoprotein (AFP) is a tumor marker of hepatocellular carcinoma (HCC) and has also been reported to reflect the effectiveness of long-term low-dose interferon (IFN) therapy in hepatitis C virus (HCV)-infected patients with chronic liver disease. The correlation between AFP levels and the incidence of HCC has been discussed over a long period. We investigated whether high levels of AFP at the time of diagnosis were associated with an increased incidence of HCC in patients with HCV. A total of 107 HCV patients with liver cirrhosis without other risks were evaluated for the predictive value of non-invasive risk factors for HCC, including age, gender, alcohol intake, aspartate and alanine aminotransferase levels, bilirubin, albumin, platelet count and AFP levels at study entry, as well as the IFN therapy received. During the follow-up period, HCC developed in 68 (63.6%) patients. Kaplan-Meier estimates were made to assess the cumulative risk of HCC. The 10-year cumulative incidence rate of HCC was 80%. Cox regression analysis was performed on several variables, including age, gender, alcohol consumption, experience of IFN therapy and biochemical parameters. The following factors were identified as exhibiting an increased risk of HCC by univariate analysis: aspartate transaminase (AST) ≥71 IU/l, alanine transaminase (ALT) ≥60 IU/l, AFP ≥6 ng/ml and IFN therapy. Multivariate analysis identified that the AFP level [6–19 ng/ml: hazard ratio (HR), 2.22; P=0.006 and ≥20 ng/ml: HR, 2.09; P=0.003] was an independent and significant risk factor for the development of HCC. A slightly elevated (6–19 ng/ml) AFP level may be a risk factor for HCC in certain cases. By contrast, AFP levels <6 ng/ml indicate a low risk of HCC development in HCV patients with liver cirrhosis.

Immunotherapy of cancer in 2012

The immunotherapy of cancer has made significant strides in the past few years due to improved understanding of the underlying principles of tumor biology and immunology. These principles have been critical in the development of immunotherapy in the laboratory and in the implementation of immunotherapy in the clinic. This improved understanding of immunotherapy, enhanced by increased insights into the mechanism of tumor immune response and its evasion by tumors, now permits manipulation of this interaction and elucidates the therapeutic role of immunity in cancer. Also important, this improved understanding of immunotherapy and the mechanisms underlying immunity in cancer has fueled an expanding array of new therapeutic agents for a variety of cancers. Pegylated interferon-α2b as an adjuvant therapy and ipilimumab as therapy for advanced disease, both of which were approved by the United States Food and Drug Administration for melanoma in March 2011, are 2 prime examples of how an increased understanding of the principles of tumor biology and immunology have been translated successfully from the laboratory to the clinical setting. Principles that guide the development and application of immunotherapy include antibodies, cytokines, vaccines, and cellular therapies. The identification and further elucidation of the role of immunotherapy in different tumor types, and the development of strategies for combining immunotherapy with cytotoxic and molecularly targeted agents for future multimodal therapy for cancer will enable even greater progress and ultimately lead to improved outcomes for patients receiving cancer immunotherapy.

Prognostic significance of alpha-fetoprotein status in the outcome of hepatocellular carcinoma after treatment of transarterial chemoembolization

BACKGROUND

Alpha-fetoprotein (AFP) has been used as a diagnostic biomarker for hepatocellular carcinoma (HCC), but its prognostic significance is not well defined. This study was performed to classify the prognostic significance of AFP status in HCC patients after transarterial chemoembolization (TACE).

METHODS

Four hundred forty-one HCC patients from a prospective maintained database with pathologic confirmation including 139 with normal AFP levels and 302 with elevated AFP levels were retrospectively studied for prognostic significance of AFP in treatment response and survival after TACE. Univariate and multivariate analyses were used to identify the prognostic factors.

RESULTS

There were significant differences in overall survival (OS) after TACE between AFP-negative and AFP-positive HCC patients when the AFP cutoff value was defined as 20 ng/ml (P < 0.0001). Among the AFP-positive patients, different AFP levels had no significantly prognostic effects on OS after TACE (P = 0.093). Multivariate analysis revealed that AFP status for AFP-negative or positive was an independent prognostic factor for HCC patients after TACE (P = 0.001), along with γ-glutamyltransferase (GGT) level (P = 0.004) and tumor diameter (P < 0.0001). In addition, there were significant differences in clinicopathologic features between AFP-positive and AFP-negative patients with regard to age, gender, alanine transferase level, GGT level, tumor diameter, and Barcelona Clinic Liver Cancer stage.

CONCLUSIONS

Compared with AFP-positive HCC patients, patients with AFP-negative status have a better treatment response and prognosis after TACE.

The Role of receptor for Advanced Glycation End Products (RAGE) in the proliferation of hepatocellular carcinoma

The receptor for advanced glycation end products (RAGE) is oncogenic and overexpressed in human cancers, but its role in hepatocellular carcinoma remains unclear. Here we demonstrated that RAGE is overexpressed in primary hepatocellular carcinoma (PHC) compared to adjacent para-neoplastic liver samples. Serum endogenous secretory RAGE levels were also increased in PHC patients (p < 0.01). Moreover, we demonstrated that RAGE regulates cellular proliferation in Hepatocellular carcinoma (HCC). Knockdown of RAGE by specific siRNA inhibited cellular growth in the hepatocellular carcinoma cell line, Huh7, whereas the RAGE ligand, high mobility group box 1 protein (HMGB1) increased cellular proliferation. In addition, knockdown of RAGE by siRNA arrested cells in the G1 phase and inhibited DNA synthesis (p < 0.01), while HMGB1 protein decreased the number of cells in the G1 phase and increased the number in the S phase (p < 0.05). Furthermore, quantitative real time RT-PCR (qRT-PCR) and Western Blot results demonstrated that RAGE and HMGB1 positively regulate NF-κB p65 expression in Huh7 cells. These studies suggest that RAGE and RAGE ligands are important targets for therapeutic intervention in hepatocellular carcinoma.

Elevated serum alpha fetoprotein levels promote pathological progression of hepatocellular carcinoma

AIM: To investigate the biological role of alpha fetoprotein (AFP) and its clinical significance in carcinogenesis of hepatocellular carcinoma (HCC).

METHODS: Clinical analysis of HCC patients and immunohistochemical examination were conducted to evaluate the relationship between serum AFP level and patient mortality. Confocal microscopy, Western blotting, dimethylthiahzolyl-2,5-diphenyl-tetrazolium bromide, Cell Counting Kit-8 assays and flow cytometry were performed to explore the possible mechanism.

RESULTS: Among the 160 HCC patients enrolled in this study, 130 patients survived 2 years (81.25%), with a survival rate of 86.8% in AFP < 2 0 μg/L group, 88.9% in AFP 20-250 μg/L group, and 69.6% in AFP > 250 μg/L group, demonstrating a higher mortality rate in HCC patients with higher AFP levels. Surgical treatment was beneficial only in patients with low AFP levels. The mortality rate of HCC patients with high AFP levels who were treated surgically was apparently higher than those treated with conservative management. The results of immunohistochemistry showed that AFP and AFP receptor were merely expressed in tissues of HCC patients with positive serum AFP. Consistently, in vitro analysis showed that AFP and AFPS were expressed in HepG2 but not in HLE cells. AFP showed a capability to promote cell growth, and this was more apparent in HepG2 cells, in which the proliferation was increased by 3.5 folds. Cell cycle analysis showed that the percentage of HepG2 cells in S phase after exposure to AFP was modestly increased.

CONCLUSION: HCC patients with higher AFP levels show a higher mortality rate, which appears to be attributable to the growth promoting properties of AFP.

Differential effects of vitamin K1 on AFP and DCP levels in patients with unresectable HCC and in HCC cell lines

PURPOSE

DCP is a useful HCC tumor marker, which reflects a defect in vitamin K metabolism. We tested the hypothesis that vitamin K treatment of HCC patients might suppress this marker and possibly AFP also.

EXPERIMENTAL DESIGN

HCC patients who had both elevated AFP and DCP were included. A phase I cohort was treated with escalating vitamin K1 intravenous weekly doses and a 27-patient phase II cohort was then treated with a fixed oral daily dose.

RESULTS

A maximum tolerated dose was not reached up to 100-fold the normal vitamin K1 dose. No toxicities were found up to 1,000 mg/infusion. In the phase II cohort, 93% of patients had tumor marker responses by decreased DCP levels, but only 22% had responses by decreased AFP levels. CT scans showed 11% of patients had PRs, 59% had stable tumors and 29.6% had tumor progression. Mechanism studies showed that vitamin K1 induced phosphorylation of JNK and c-Jun and caspase-mediated apoptosis.

CONCLUSIONS

Vitamin K1 was non-toxic at high doses, strongly inhibited plasma DCP levels, but weakly suppressed AFP levels. The results provide evidence that the two tumor markers are not directly linked and that DCP levels may not reflect HCC cell growth, as DCP levels were decreased in patients without AFP change, and were suppressed in vitro at 1% of the vitamin K1 concentration needed to inhibit AFP.

Acute liver injury upregulates microRNA-491-5p in mice, and its overexpression sensitizes Hep G2 cells for tumour necrosis factor-alpha-induced apoptosis

BACKGROUND

MicroRNAs (miRNAs) have emerged as novel genetic regulators of cell functions such as proliferation, apoptosis and cancer.

AIMS

The aim of this study was to evaluate the role of a specific miRNA in modulating hepatic cell functions.

METHODS

C57Bl/6 mice were administered anti-fas receptor antibodies to induce liver cell apoptosis. miRNAs were purified from the liver tissue and evaluated using an miRNA microarray. The role of miRNA-491_5p, which was overexpressed in the model, in modulating hepatic cell functions was evaluated. miRNA-491_5p was overexpressed in Hep G2 cells, followed by the addition of tumour necrosis factor (TNF)-alpha, and induction of apoptosis as well as genes involved in apoptosis pathways were evaluated. The effect of miRNA-491_5p target genes on apoptosis was also analysed by inhibiting their expression by siRNA-induced gene silencing.

RESULTS

Upregulation of miRNA-491_5p was found in a high-dose anti-fas receptor antibody group. Overexpression of microRNA-491_5p sensitized Hep G2 cells for TNF-alpha-induced apoptosis, and also caused an inhibition of alpha-fetoprotein, (AFP), heat shock protein-90 (hsp-90) and nuclear factor-kappaB (NF-kappaB). Overexpression of miRNA-491_5p or inhibition of AFP and hsp-90 resulted in an increased apoptosis in TNF-alpha-treated Hep G2 cells.

CONCLUSIONS

One of the miRNAs that is associated with the acute liver injury mouse model, miRNA-491_5p, sensitizes Hep G2 cells for TNF-alpha-induced apoptosis, at least in part, by inhibiting AFP, hsp-90 and NF-kappaB.

Alpha-fetoprotein gene polymorphisms and risk of HCC and cirrhosis

BACKGROUND

Elevated level of alpha fetoprotein (AFP) is found in approximately 60% of hepatocellular carcinoma (HCC) cases. Other liver diseases including cirrhosis and chronic hepatitis are related with an increased level of AFP. The regulation of AFP gene expression has been relatively less studied although the gene has been suggested to play a role in HCC development. This study aimed at identifying genetic variations in AFP that might be associated with the presence of HCC and cirrhosis among ethnic Indonesians.

METHODS

Direct DNA sequencing was carried out to sequence AFP promoter, exons, and 3' untranslated region (UTR) in DNA samples isolated from 119 HCC, 119 cirrhosis and 105 control subjects. For each sample serum AFP level was determined and association studies with single nucleotide polymorphisms (SNPs) and haplotypes were performed.

RESULTS

In this study we identified 47 SNPs in the AFP gene. Statistically significant associations with HCC and cirrhosis were detected for six individual SNPs in the AFP promoter, AFP intron 1 and intron 2 (rs6834059, rs3796678, rs3796677, rs3796676, rs28532518 and rs4646038). Furthermore, we identified two SNPs in AFP intron 7 and 3'UTR, rs2298839 and rs10020432, which are associated with increased risk of cirrhosis.

CONCLUSION

Genetic variants in the AFP gene may be associated with HCC and cirrhosis risk for ethnic Indonesians.

Applications of RNA interference in cancer therapeutics as a powerful tool for suppressing gene expression

Cancer poses a tremendous therapeutic challenge worldwide, highlighting the critical need for developing novel therapeutics. A promising cancer treatment modality is gene therapy, which is a form of molecular medicine designed to introduce into target cells genetic material with therapeutic intent. The history of RNA interference (RNAi) has only a dozen years, however, further studies have revealed that it is a potent method of gene silencing that has developed rapidly over the past few years as a result of its extensive importance in the study of genetics, molecular biology and physiology. RNAi is a natural process by which small interfering RNA (siRNA) duplex directs sequence specific post-transcriptional silencing of homologous genes by binding to its complementary mRNA and triggering its elimination. RNAi has been extensively used as a novel and effective gene silencing tool for the fundamental research of cancer therapeutics, and has displayed great potential in clinical treatment.