Therapeutic Approach For Hepatocellular Carcinoma Research Articles

Expression of CHODL in hepatocellular carcinoma affects invasion and migration of liver cancer cells.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-associated death. Due to rapid progression and metastasis, the long-term survival remains poor for most patients. Thus, it is important to discover and develop novel preventive strategies and therapeutic approaches for HCC. Recent data show that chondrolectin (CHODL) is commonly overexpressed in the majority of lung cancers, indicating a possible correlation between CHODL and metastasis of lung cancer cells. Our investigation shows that the expression of CHODL is significantly decreased in HCC clinical samples and in HCC cell lines. Overexpression of CHODL in SMMC7721 cells with a lentiviral vector increased SMMC7721 cell migration and invasion. Our findings establish for the first time an association between human CHODL and HCC metastasis.

Lipid rafts promote liver cancer cell proliferation and migration by up-regulation of TLR7 expression

Hepatocellular carcinoma (HCC) occurs predominantly in patients with underlying chronic liver disease and cirrhosis. Toll-like receptors (TLRs) play an important role in innate immune responses and TLR signaling has been associated with various chronic liver diseases. Lipid rafts provide the necessary microenvironment for certain specialized signaling events to take place, such as the innate immune recognition. The purpose of this study was to determine the pattern of TLR7 expression in HCC, how to recruit TLR7 into lipid rafts responded to ligands and whether targeting TLR7 might have beneficial effects. The study group was comprised of 130 human liver tissues: 23 chronic hepatitis B (CHB), 18 liver cirrhosis (LC), 68 HCC and 21 normal livers. The expression of TLR7 was evaluated using immunohistochemistry, western blotting, and flow cytometry. Proliferation and migration of human HepG2 cells were studied following stimulation of TLR7 using the agonist gardiquimod and inhibition with a specific antagonist 20S-protopanaxadiol (aPPD). The activation of lipid raft-associated TLR7 signaling was measured using western blotting, double immunohistochemistry and immunoprecipitation in liver tissues and HepG2 cells. TLR7 expression was up-regulated in human HCC tissues and hepatoma cell line. Proliferation and migration of HepG2 cells in vitro increased significantly in response to stimulation of TLR7. TLR7 inhibition using aPPD significantly reduced HepG2 cell migration in vitro. The lipid raft protein caveolin-1 and flotillin-1 were involved with enhanced TLR7 signaling in HCC.ConclusionsThe data suggest that inhibiting TLR7 with antagonists, like aPPD, could potentially be used as a novel therapeutic approach for HCC.

Integrating subpathway analysis to identify candidate agents for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the second most common cause of cancer-associated death worldwide, characterized by a high invasiveness and resistance to normal anticancer treatments. The need to develop new therapeutic agents for HCC is urgent. Here, we developed a bioinformatics method to identify potential novel drugs for HCC by integrating HCC-related and drug-affected subpathways. By using the RNA-seq data from the TCGA (The Cancer Genome Atlas) database, we first identified 1,763 differentially expressed genes between HCC and normal samples. Next, we identified 104 significant HCC-related subpathways. We also identified the subpathways associated with small molecular drugs in the CMap database. Finally, by integrating HCC-related and drug-affected subpathways, we identified 40 novel small molecular drugs capable of targeting these HCC-involved subpathways. In addition to previously reported agents (ie, calmidazolium), our method also identified potentially novel agents for targeting HCC. We experimentally verified that one of these novel agents, prenylamine, induced HCC cell apoptosis using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, an acridine orange/ethidium bromide stain, and electron microscopy. In addition, we found that prenylamine not only affected several classic apoptosis-related proteins, including Bax, Bcl-2, and cytochrome c, but also increased caspase-3 activity. These candidate small molecular drugs identified by us may provide insights into novel therapeutic approaches for HCC.

The novel mTOR inhibitor Torin-2 induces autophagy and downregulates the expression of UHRF1 to suppress hepatocarcinoma cell growth.

Mammalian target of rapamycin (mTOR) is frequently upregulated in hepatocellular carcinoma (HCC). Blockage of mTOR was found to induce marked reduction in HCC growth in preclinical models. In the present study, we tested a novel mTOR inhibitor, Torin-2, for its antitumor efficacy in HCC cell lines Hep G2, SNU-182 and Hep 3B2.1-7. The HCC cell lines were cultured in vitro. These cells were treated with Torin-2. Cell apoptosis was evaluated by Annexin V staining. Cell proliferation and cell cycle progression were determined by Ki67 staining and propidium iodide staining, respectively. mTOR signaling, autophagy induction and expression of ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) were assessed by western blot analysis. The UHRF1 mRNA level was determined by real-time PCR. We found that Torin-2 effectively suppressed the growth and survival of HCC cell lines, demonstrated by reduced proliferation and a high rate of apoptosis. Further study elucidated that in addition to blocking mTOR complex 1 (mTORC1)-associated cell cycle progression and induction of autophagy, Torin-2 downregulated transcription of UHRF1, an essential regulator of DNA methylation that is highly expressed in HCC cell lines. Consistently, the level of DNA (cytosine-5)-methyltransferase 1 (DNMT1) was higher after treatment of the HCC cell lines with Torin-2. The downregulation of UHRF1 by Torin-1 was partially due to a decrease in the UHRF1 mRNA level. Torin-2 effectively inhibited HCC cell proliferation through induction of autophagy. Torin‑2-induced downregulation of UHRF1 expression may also contribute to its antitumor effect. Our research provides new clues regarding the antitumor effects of Torin-2 and sheds light on a novel therapeutic approach for HCC.

Growth Arrest Specific 1 (Gas1) Gene Overexpression in Liver Reduces the In Vivo Progression of Murine Hepatocellular Carcinoma and Partially Restores Gene Expression Levels.

The prognosis of hepatocellular carcinoma patients is usually poor, the size of tumors being a limiting factor for surgical treatments. Present results suggest that the overexpression of Gas1 (growth arrest specific 1) gene reduces the size, proliferating activity and malignancy of liver tumors. Mice developing diethylnitrosamine-induced hepatocellular carcinoma were subjected to hydrodynamic gene delivery to overexpress Gas1 in liver. This treatment significantly (p < 0.05) reduced the number of large tumors, while the difference in the total number of lesions was not significant. Moreover, the number of carcinoma foci in the liver and the number of lung metastases were reduced. These results are related with the finding that overexpression of Gas1 in Hepa 1-6 cells arrests cell cycle before S phase, with a significant (p < 0.01) and concomitant reduction in the expression of cyclin E2 gene. In addition, a triangular analysis of microarray data shows that Gas1 overexpression restores the transcription levels of 150 genes whose expression was affected in the diethylnitrosamine-induced tumors, thirteen of which are involved in the hedgehog signaling pathway. Since the in vivo Gas1 gene delivery to livers of mice carrying hepatocellular carcinoma reduces the size and proliferating activity of tumors, partially restoring the transcriptional profile of the liver, the present study opens promising insights towards a therapeutic approach for hepatocellular carcinoma.

Targeting angiogenic genes as a therapeutic approach for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a complex liver disease with limited treatment options and often resulting in a poor prognosis. The development of HCC depends on the formation of new blood vessels and it demonstrates hypervascularity and invasive property to the surrounding vasculature clinically. A complex network of growth factors acting on both tumor cells and endothelial cells mediates the angiogenesis in HCC. It is an attractive approach to inhibit the angiogenic processes as the treatment of HCC and therefore, anti-angiogenic TKIs were developed to inhibit the vessel formation in the tumors. However, it is currently perceived that the efficacy of these anti-angiogenic TKIs has reached plateau, and it is necessary to develop novel agents with non-TKI mechanism to inhibit the angiogenic targets. With the better understanding of molecular mechanisms that govern angiogenesis, as well as the advancement in biomedical engineering, new approaches of gene therapy have brought hopes for therapeutic intervention in HCC. Gene therapy is based on the transfer of genetic material to the patients with the aim to modify or correct the malignancy from its molecular basis. In this article, we will discuss the conventional anti-angiogenic therapies and the gene therapy approaches in HCC. The therapeutic potential of gene therapy for HCC treatment has been demonstrated and further development of anti-angiogenic may result in new treatment option for HCC patients.

Overexpression of PSF1 is correlated with poor prognosis in hepatocellular carcinoma patients.

PSF1 is a subunit of the GINS complex which is essential for establishment of DNA replication forks, and the progression of the replisome. Previous studies have shown a close relationship between PSF1 and cell cycle in the proliferation of immature cells as well as tumors. The purpose of this study was to measure PSF1 expression in hepatocellular carcinoma (HCC) tissues, and determine the effects of down-regulation of PSF1 expression on growth of cancer cells, the cell cycle, apoptosis and cell invasiveness. Samples from 137 HCC tissues, 67 from adjacent nontumor tissue and 15 from normal liver were studied using immunochemistry. The HepG2 cell line was used for knockdown experiments studied by RT-PCR, real-time PCR, apoptosis and invasiveness assays. PSF1 was overexpressed in HCC tissues compared with normal liver tissues. High PSF1 expression correlated with a more aggressive phenotype as well as worse prognosis in HCC patients. Knockdown of PSF1 expression using small interfering RNA (siRNA) slowed the growth of cancer cell by suppressing the cell cycle progression as well as increasing apoptosis, especially early apoptosis. In addition, the invasiveness of HepG2 cells was also reduced by down-regulation of PSF1. These results suggest that the inhibition of PSF1 might provide new therapeutic approaches for HCC.

NAD+ Supplementation as a Novel Approach to cURIng HCC?

In this issue of Cancer Cell, Tummala and colleagues demonstrate that unconventional prefoldin RPB5 interactor (URI) expression in hepatocytes leads to hepatocellular carcinoma (HCC) development by interacting with L-tryptophan/kynurenine/nicotinamide adenine dinucleotide (NAD(+)) metabolism. The results suggest that supplementation of NAD(+) may be a prophylactic or therapeutic approach in HCC.

Abstract 2453: Transketolase (TKT) is a critical component of the metabolic machinery of hepatocellular carcinoma (HCC)

Abstract Hepatocellular carcinoma, HCC, is one of the commonest malignant cancers in human liver. The prognosis of HCC patients is extremely poor mainly because of late symptom presentation and absence of effective therapy. Liver is the metabolic engine that maintains the homeostasis of various nutrients; nevertheless, how the metabolic reprogramming of HCC cells benefits tumor progression remains largely unknown. Understanding the metabolic machinery of HCC is important for the development of new therapeutic approaches for HCC. Increased glucose intermediates through glycolysis and the pentose phosphate pathway (PPP) is a metabolic signature of cancer. The PPP works collaboratively with glycolysis to support rapid tumor growth by producing NADPH, the major antioxidant in the cells, and ribose-5-phosphate, the backbone of RNA. One of the key enzymes that connect PPP with glycolysis is the transketolase family (TK). The TK family comprises 3 members namely transketolase (TKT), TKT-like 1 (TKTL1) and TKTL2. Many studies have indicated that strong TKTL1 protein expression was correlated with invasive features and poor clinical outcome in other cancers. However, our transcriptome sequencing data from 16 pairs of human HCC and non-tumorous liver (NT) tissues revealed that (1) the TKT is the predominant TK member in the liver and HCC; (2) TKT, but not other TK family members, is overexpressed in HCC. In an expanded HCC cohort consisting of 60 human HCC cases, we confirmed that TKT is significantly overexpressed and is closely associated with aggressive HCC clinicopathological features including tumor microsatellite formation (P = 0.04), venous invasion (P = 0.01), and large tumor size (P = 0.04). Stable knockdown of TKT by various short hairpin RNA (shRNA) sequences in multiple HCC cell lines (MHCC97L, SMMC-7721, and BEL-7402) consistently suppressed cell growth, elevated intracellular ROS level (CM-H2DCFDA staining), and decreased glucose uptake (2-NBDG staining). In line with the in vitro observations, stable knockdown of TKT drastically impeded HCC growth in orthotropic and subcutaneous tumor models. More interestingly, pharmacological inhibition and genetic knockdown of TKT by oxythiamine (OT) and shRNA, respectively, sensitized HCC cells to the treatment of 2-deoxyglucose (2-DG), a glycolysis inhibitor. Inhibition of PPP and glycolysis by co-treatment of OT and 2-DG completely suppressed HCC growth. Taken together, our present data suggested that TKT overexpression strongly favors HCC cell growth in vitro and in vivo. Our data also showed that TKT is a critical component of the metabolic machinery of HCC and therefore an attractive therapeutic target. Citation Format: Mingjing Xu, Carmen Chak-Lui Wong, Irene Oi-Lin Ng. Transketolase (TKT) is a critical component of the metabolic machinery of hepatocellular carcinoma (HCC). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2453. doi:10.1158/1538-7445.AM2014-2453

The iron chelator Dp44mT inhibits hepatocellular carcinoma metastasis via N-Myc downstream-regulated gene 2 (NDRG2)/gp130/STAT3 pathway.

Here we showed that hepatocellular carcinoma (HCC) cell lines with high metastatic potential had low levels of NDRG2. The iron chelator Dp44mT up-regulated NDRG2, suppressed epithelial-mesenchymal transition (EMT) and inhibited tumor metastasis in HCC having high metastatic potential. Also Dp44mT attenuated the TGF-β1-induced EMT in HCC having low metastatic potential. In agreement, silencing endogenous NDRG2 with shNDRG2 in HCC cells attenuated the effect of Dp44mT. We showed that the NDRG2/gp130/STAT3 pathway can mediate Dp44mT effects. In agreement, we found that a combination of NDRG2 expression and p-STAT3 levels is a strong predictor of prognosis in HCC patients. We suggest that up-regulation of NDRG2 by Dp44mT is a promising therapeutic approach in HCC.

Combination of Cetuximab and Rapamycin Enhances the Therapeutic Efficacy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly cancers worldwide. It is well known that the activation of PI3K/AKT/mTOR and the Ras/MAPK signaling pathway plays a critical role in cellular metabolism, growth and proliferation, and its inhibitors have been used as therapeutic drugs for hepatocellular carcinoma. Cetuximab, a chimerical monoclonal EGFR IgG1 antibody, can block the binding of EGF or other ligands to EGFR and thus inhibit ligands-induced receptor phosphorylation. In the present study, we found that rapamycin could enhance the antiproliferation effect of cetuximab in both HepG2 cells and Huh-7 cells and arrest the cell cycle. Cetuximab in combination with rapamycin had synergistic effects on inhibiting the phosphrylation of proteins in PI3K/AKT/mTOR and Ras/MAPK signaling pathway. Combination of cetuximab with rapamycin treatment significantly suppressed the HCC development in HepG2 cells-xenografted mice and improved the survival. Cetuximab and rapamycin inhibited the growth of HCC both in vitro and in vivo. These results suggest that the combination therapy using the inhibitors for both EGFR and PI3K/AKT/mTOR signaling pathways may be a novel therapeutic approach for HCC.

Targeting Gap Junction Intercellular Communication as a Potential Therapy for HCV-Related Carcinogenesis

ABSTRACT: Worldwide, at least 170 million people are infected with hepatitis C virus (HCV), which is associated with hepatocellular carcinoma (HCC). With the recent success of Sofosbuvir (and other agents) antiviral therapy may be used as a future early-stage HCC treatment; however, in the short term, a cost-effective solution is needed to treat patients with viral-associated HCC. Here, we emphasize the potential of targeting gap junction intercellular communication (GJIC) as a therapeutic approach for HCC as HCV perturbs GJIC, which is linked to cellular transformation. We review the ROCK inhibitor Y-27632 and structurally related compounds that may inhibit the carcinogenic properties of HCV.

Effects of short interfering RNA-mediated gene silencing of SKA1 on proliferation of hepatocellular carcinoma cells

Background. Hepatocellular carcinoma (HCC) is one of the common causes of cancer resulting in death in China. Here, we found that spindle- and kinetochore-associated complex subunit 1 (SKA1) is a critical factor that plays an essential role in the regulation of HCC cell proliferation and apoptosis. Methods. Using immunohistochemistry in 38 HCC tissues, we showed that the expression of SKA1 was upregulated in HCC tissues compared with the normal tissues. Then, we investigated the effects of SKA1-targeted small interfering RNA (siRNA) on the HCC cell proliferation and apoptosis as of HCC cells. SKA1-targeted siRNA was delivered to HCC SMMC-7721 and Bel-7404 cells to evaluate its antiproliferation effects using lentivirus. Results. The lentivirus-mediated siRNA-targeting SKA1 treatment leads to a significant (p < 0.01) downregulation of SKA1 expression at mitochondrial RNA (mRNA) level. Knockdown of SKA1 inhibited HCC cell proliferation by inducing cell cycle arrest in the G0/G1 phase. Furthermore, lentivirus-mediated siRNA efficiently inhibited cell proliferation and colony formation while promoting the apoptosis. Conclusions. Of note, our data suggest that SKA1 might play an important role in the proliferation of HCC cells, and the absence of this gene in HCC may open promising therapeutic approaches for HCC.

Co-delivery of LETM1 and CTMP synergistically inhibits tumor growth in H-ras12V liver cancer model mice

As hepatocellular carcinoma (HCC) is one of the most common tumors worldwide, development of novel therapeutic approaches for HCC is urgently needed. Two different genes, LETM1 and CTMP, which target mitochondrial functions, were chosen and linked using 2A-peptide sequence. Successful self-cleavage of 2A-peptide induced synergistic antitumor effect in the liver of H-ras12V, the HCC model mice, by simultaneous activation of LETM1 (Leucine zipper/EF hand-containing transmembrane-1) and CTMP (carboxyl-terminal modulator protein). Overexpression of LETM1 and CTMP significantly reduced the incidence of tumorigenesis, which were confirmed by gross and microscopic observations. Morphological changes in mitochondria, such as swelling and loss of cristae, were significant, and the prolonged activation of defects in mitochondrial function led to mitochondria-mediated apoptosis. Furthermore, with CTMP as a direct binding partner of Akt1, and LETM1 as a binding partner of CTMP, LETM1-2A-CTMP downregulated the Akt1 pathway at both Ser473 and Thr308 sites of phosphorylation. Proliferation and angiogenesis, which are important in cancer prognosis, were reduced in tumor sites after introduction of LETM1-2A-CTMP. Taken together, the results indicate that introduction of the mitochondria-targeting genes, LETM1 and CTMP, and self-processing capacity of 2A-peptide sequence exerts an antitumor effect in liver of H-ras12V mice, suggesting its potential as a tool for gene therapy.

Active treatments are a rational approach for hepatocellular carcinoma in elderly patients

To determine whether an active intervention is beneficial for the survival of elderly patients with hepatocellular carcinoma (HCC). The survival of 740 patients who received various treatments for HCC between 1983 and 2011 was compared among different age groups using Cox regression analysis. Therapeutic options were principally selected according to the clinical practice guidelines for HCC from the Japanese Society of Hepatology. The treatment most likely to achieve regional control capability was chosen, as far as possible, in the following order: resection, radiofrequency ablation, percutaneous ethanol injection, transcatheter arterial chemoembolization, transarterial oily chemoembolization, hepatic arterial infusion chemotherapy, systemic chemotherapy including molecular targeting, or best supportive care. Each treatment was used alone, or in combination, with a clinical goal of striking the best balance between functional hepatic reserve and the volume of the targeted area, irrespective of their age. The percent survival to life expectancy was calculated based on a Japanese national population survey. The median ages of the subjects during each 5-year period from 1986 were 61, 64, 67, 68 and 71 years and increased significantly with time (P < 0.0001). The Child-Pugh score was comparable among younger (59 years of age or younger), middle-aged (60-79 years of age), and older (80 years of age or older) groups (P = 0.34), whereas the tumor-node-metastasis stage tended to be more advanced in the younger group (P = 0.060). Advanced disease was significantly more frequent in the younger group compared with the middle-aged group (P = 0.010), whereas there was no difference between the middle-aged and elderly groups (P = 0.75). The median survival times were 2593, 2011, 1643, 1278 and 1195 d for 49 years of age or younger, 50-59 years of age, 60-69 years of age, 70-79 years of age, or 80 years of age or older age groups, respectively, whereas the median percent survival to life expectancy were 13.9%, 21.9%, 24.7%, 25.7% and 37.6% for each group, respectively. The impact of age on actual survival time was significant (P = 0.020) with a hazard ratio of 1.021, suggesting that a 10-year-older patient has a 1.23-fold higher risk for death, and the overall survival was the worst in the oldest group. On the other hand, when the survival benefit was evaluated on the basis of percent survival to life expectancy, age was again found to be a significant explanatory factor (P = 0.022); however, the oldest group showed the best survival among the five different age groups. The youngest group revealed the worst outcomes in this analysis, and the hazard ratio of the oldest against the youngest was 0.35 for death. The survival trends did not differ substantially between the survival time and percent survival to life expectancy, when survival was compared overall or among various therapeutic interventions. These results suggest that a therapeutic approach for HCC should not be restricted due to patient age.

Combined Phosphatase and Tensin Homolog (PTEN) Loss and Fatty Acid Synthase (FAS) Overexpression Worsens the Prognosis of Chinese Patients with Hepatocellular Carcinoma

We aimed to investigate the expression pattern of phosphatase and tensin homolog (PTEN), to evaluate the relationship between PTEN expression and clinicopathological characteristics, including fatty acid synthase (FAS) expression, and to determine the correlations of PTEN and FAS expression with survival in Chinese patients with hepatocellular carcinoma (HCC). The expression patterns of PTEN and FAS were determined using tissue microarrays and immunohistochemistry. The expression of PTEN was compared with the clinicopathological characteristics of HCC, including FAS expression. Receiver operator characteristic curves were used to calculate the clinical sensitivity and specificity of PTEN expression. Kaplan-Meier survival curves were constructed to evaluate the correlations of PTEN loss and FAS overexpression with overall survival. We found that the loss of PTEN expression occurred predominantly in the cytoplasm, while FAS was mainly localized to the cytoplasm. Cytoplasmic and total PTEN expression levels were significantly decreased in HCC compared with adjacent non-neoplastic tissue (both, p < 0.0001). Decreased cytoplasmic and total PTEN expression showed significant clinical sensitivity and specificity for HCC (both, p < 0.0001). Downregulation of PTEN in HCC relative to non-neoplastic tissue was significantly correlated with histological grade (p = 0.043 for histological grades I–II versus grade III). Loss of total PTEN was significantly correlated with FAS overexpression (p = 0.014). Loss of PTEN was also associated with poor prognosis of patients with poorly differentiated HCC (p = 0.049). Moreover, loss of PTEN combined with FAS overexpression was associated with significantly worse prognosis compared with other HCC cases (p = 0.011). Our data indicate that PTEN may serve as a potential diagnostic and prognostic marker of HCC. Upregulating PTEN expression and inhibiting FAS expression may offer a novel therapeutic approach for HCC.

Effects of E2F1–cyclin E1–E2 circuit down regulation in hepatocellular carcinoma cells

Background No effective therapy is available for hepatocellular carcinoma. To identify novel therapeutic strategies, we explored the effects of the depletion of E2F1, cyclin E1–E2 whose inter-relationships in hepatocellular carcinoma cell proliferation have never been defined. Methods siRNA-mediated depletion of the targets was studied in the hepatocellular carcinoma cells HepG2, HuH7 and JHH6 characterized by high, medium and low hepatocyte differentiation grade, respectively; a model of normal human hepatocytes was also considered. Results The depletion of each target mRNA reduced the levels of the other two mRNAs, thus demonstrating a close regulatory control, also confirmed by over-expression experiments. At the protein level, an exception to this trend was observed for cyclinE1 whose amount increased upon cyclin E2 (HepG2, HuH7, JHH6) and E2F1 (HepG2) depletion. In HepG2, reduced cyclinE1 proteolysis accounted for this observation. Additionally, cyclin E1–E2–E2F1 targeting decreased the levels of cyclin A2 mRNA and of the hyper-phosphorylated form of pRb thus leading to an S-phase cell decrease; migration was impaired as well. Finally, the model of human hepatocytes used was clearly less affected by target mRNAs depletion than hepatocellular carcinoma cells. Conclusion Our data provide novel mutual relationships amongst cyclin E1–E2–E2F1 and indicate their role in sustaining hepatocellular carcinoma cell proliferation/migration, validating the concept of an anti-cyclin E1–E2–E2F1 therapeutic approach for hepatocellular carcinoma.

Hypermethylated levels of E-cadherin promoter in Huh-7 cells expressing the HCV core protein

Background and aimThe mechanisms of hepatocarcinogenesis induced by hepatitis C virus remain unclear. Our aim was to investigate the effect of the HCV core protein on the promoter methylation status of selected genes potentially involved in the hepatocellular carcinoma (HCC). Materials and methodsWe evaluated the promoter methylation levels of the E-cadherin (CDH1), the glutathione S-transferase p1 (GSTP1), adenomatosis polyposis coli (APC), tissue inhibitor of metalloproteinase 3 (TIMP3), catenin (cadherin-associated protein) beta 1 (CNNTB1) genes by a quantitative methylation-specific polymerase chain reaction (QMSP) in the in vitro model of Huh-7 cells expressing the HCV core protein of genotype 1b. ResultsWe found that CDH1 promoter was hypermethylated in genotype 1b HCV core protein-positive cells as compared to control cells expressing the GFP protein alone (HCV core 1b vs GFP p=0.00; HCV core 1b vs Huh-7 p=0.03). This resulted in reduced levels of CDH1 protein as evaluated by immunoblot and by immunofluorescence. On the other hand no significant changes were observed for the other genes investigated. Furthermore, we present evidence that genotype 1b HCV core protein expression induces SIRT1 upregulation and that treatment with SIRT1 inhibitor sirtinol decreases the methylation levels of CDH1 promoter (1b+sirtinol vs 1b p=0.05; 1b+sirtinol vs GFP+sirtinol p=NS) resulting in 1.7-fold increased CDH1 mRNA expression (1b+sirtinol vs 1b p=0.05). ConclusionsOur findings suggest that HCV core protein could play a role in HCC at least in part by altering the methylation status of CDH1 promoter. These findings could also suggest a novel therapeutic approach for HCC.

Intra-atrial tumor thrombi secondary to hepatocellular carcinoma responding to chemotherapy

Context:Hepatocellular carcinoma accounts for 1-2.5% of all cancer in America with extension to inferior vena cava and right atrium in 1-4% of the cases. Patients with advanced hepatocellular carcinoma invading the right heart are considered poor candidates for surgery. In the past, such patients had dismal prognosis due to complications like pulmonary embolism and sudden death.Case Report:Our patient was admitted with worsening jaundice, abdominal pain and significant weight loss. Abdominal ultrasound, elevated alfa feto-protein levels and computerized tomography pointed to the diagnosis of hepatocellular carcinoma. Transthoracic echocardiography demonstrated two masses in the right atrium with the base of masses extending from inferior vena cava into right atrium. The patient was diagnosed to have stage IV heptaocellular carcinoma. This is associated with dismal prognosis. But after being started on sorafenib, the tumor regressed considerably and was barely discernable on echocardiography performed a month later.Conclusion:Though aggressive surgical resection is the best therapeutic approach for hepatocellular carcinoma, it may not always be possible and in such cases combination of different therapeutic approaches such as chemotherapeutic agents, radiotherapy and chemoembolization may improve survival.

Antitumoral effect of farnesiltransferase and mtor inhibitors in hepatocellular carcinoma: in vitro studies

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, often diagnosed at an advanced stage when the most potentially curative strategies are no longer effective. Advances in the understanding of tumor biology are opening new paths for the prevention and treatment of HCC, through the development of new targeted therapies. The design of drugs that block different growth-promoting pathways, activate apoptotic pathways may also open new horizons in the treatment of HCC. The aim of this study was to test the efficacy of new targeted drugs involved in signalling pathways, such as farnesiltransferase (L-744832) and mTOR inhibitors (everolimus) in a HCC cell line (HUH-7 cells). The HUH-7 cells were cultured in absence and presence of different concentrations of L-744832 and everolimus. The antiproliferative effect was assessed by the Alamar Blue assay and cell death by optic microscopy and flow cytometry. Our results showed that farnesiltransferase and mTOR inhibitors had an antiproliferative and cytotoxic effects in monotherapy in a dose and time dependent manner, inducing cell death preferentially by apoptosis. On, the other hand, the combination of L-744832 and everolimus with conventional anticarcinogenic drugs demonstrated a higher antiproliferative and cytotoxic effect for lower doses than the IC50 used in monotherapy (addition or potentiation synergism). These results suggested that farnesiltransferase and mTOR inhibitors may constitute a new potential therapeutic approach in HCC either in monotherapy or in association with conventional therapies.