Management of hepatocellular cancer

Restoring NK cells functionality via cytokine activation enhances cetuximab-mediated NK-cell ADCC: A promising therapeutic tool for HCC patients

Natural Killer (NK) cells are considered the first line of defense against viral infections and tumors. Several factors affect NK cytotoxic activity rendering it dysfunctional and thereby impeding the ability to scavenge abnormal cells as a part of immune escaping mechanisms induced by different types of cancers. NK cells play a crucial role augmenting the activity of various types of anticancer mAb since dysfunctional NK cells are the main reason for the low response to these therapies. To this light, we examined the phenotypic characters of the circulating NK cells isolated from HCC patients compared to healthy controls. Then, dysfunctional NK cells, from HCC patients, were reactivated with cytokines cocktail and their cytotoxic activity with the anti-EGFR mAb "cetuximab" was investigated. This showed a downregulation of patients NK cells activating receptors (NKP30, NKP46, NKG2D and CD16) as well as CD56 and up-regulation of NKG2A inhibitory receptor. We also reported an increase in aberrant CD56^- NK cells subset in peripheral blood of HCC patients compared to healthy controls. Thus, confirming the dysfunctionality of peripheral NK cells isolated from HCC patients. Cytokines re-activation of those NK cells lead to upregulation of NK activating receptors and downregulation of inhibitory receptor. Moreover, the percentage of aberrant CD56^- NK cells subset was reduced. Here, we proved that advanced HCC patients have an increased percentage of more immature and noncytotoxic NK cell subsets in their peripheral blood, which might account for the low cytotoxicity noticed in those patients. A significant improvement in the cytotoxicity against HCC was noticed upon using reactivated NK cells combined with cetuximab. Therefore, this study highlights the potential recruitment of NK immune cells along with cetuximab to enhance cytotoxicity against HCC.

Natural History of Incidental Enhancing Nodules on Cone-Beam Computed Tomography during Transarterial Therapy of Hepatocellular Carcinoma

PURPOSE

To evaluate the natural history of incidental enhancing nodules (IENs) on contrast-enhanced cone-beam computed tomography (CT) during transarterial treatment of hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

A single-center retrospective analysis of 100 patients with HCC who underwent contrast-enhanced cone-beam CT prior to transarterial treatment from August 2015 to June 2019 was performed. Inclusion criteria were patients with segmental distribution sublobar HCC, contrast-enhanced cone-beam CT of the target lesion and nontarget liver parenchyma, and follow-up cross-sectional imaging. Patients with IENs ≥3 mm that did not meet imaging criteria for HCC were analyzed. Exclusion criteria included biphenotypic tumors and IEN present inside the treated area of the liver.

RESULTS

Fifty-six patients demonstrated 154 IENs on contrast-enhanced cone-beam CT, of which 13 IENs (8.5%) progressed to HCC. The mean primary tumor size was 29 mm (range: 10.2-189 mm). Ten patients had ≥4 IENs, and 46 patients had 1-3 IENs. The mean IEN size was 6.8 mm (range: 3.0-16.3 mm). The median follow-up interval after contrast-enhanced cone-beam CT was 282 days (interquartile range: 143-522). Increased alpha-fetoprotein before treatment (≥15.5 ng/mL, P = .035), having ≥4 IENs (P = .020), and hepatitis C virus (P = .015) were significantly correlated with IEN progression to HCC. No statistically significant differences were identified in baseline neutrophil-to-lymphocyte ratio, targeted HCC characteristics (size, macrovascular invasion, infiltrative pattern, enhancement pattern, and satellite lesions), and IEN size between those with IEN progression to HCC and those without.

CONCLUSIONS

Most IENs of ≥3 mm on contrast-enhanced cone-beam CT in patients with segmental distribution sublobar HCC do not progress to HCC. Patients with segmental distribution sublobar HCC with ≥4 IENs, alpha-fetoprotein elevation (≥15.5 ng/mL), or hepatitis C virus have an increased risk of IEN progression to HCC.

A study of the mechanism of lncRNA-CR594175 in regulating proliferation and invasion of hepatocellular carcinoma cells in vivo and in vitro

Background

Hepatocellular carcinoma (HCC) is one of the cancers of highest incidence and mortality worldwide. The proliferation and invasion of tumor cells are the main reason for poor prognosis after HCC surgery. Long non-coding RNA (lncRNA) has been shown to play a key role in the progression of HCC. LncRNA-CR594175 is one of the highly expressed lncRNAs in HCC tumors and their metastatic tumors that we have obtained by the High-throughput screening method.

Methods

To elucidate the role of lncRNA-CR594175 in regulating the proliferation and invasion of human hepatoma cell line, HepG2, we operated through lncRNA-CR594175 silencing to inhibit the progression of HCC, either through in vitro or in vivo experiments.

Results

We found that lncRNA-CR594175 was lower in adjacent non-cancerous tissues than in primary HCC, and was lower in primary HCC than in its metastasis. Silencing of lncRNA-CR594175 inhibited the proliferation and invasion of HepG2 cells and growth of subcutaneous tumors. The results revealed that lncRNA-CR594175, as a RNA sponge, broke the negative regulation of hsa-miR-142-3p on Catenin, beta-1 (CTNNB1), and once lncRNA-CR594175 was silenced, the hsa-miR142-3p regained its negative regulation on CTNNB1 which can promote HCC progression by activating the wnt pathway.

Conclusions

Our present study demonstrated for the first time that lncRNA-CR594175 silencing suppressed proliferation and invasion of HCC cells in vivo and in vitro by restoring the negative regulation of hsa-miR-142-3p on CTNNB1, laying a solid theoretical base for using lncRNA-CR594175 as genetic target therapy for HCC and offering a reasonable explanation for inactivation of miRNA in different tumors or in the tumor at different stages.

Combined treatment with zingerone and its novel derivative synergistically inhibits TGF-β1 induced epithelial-mesenchymal transition, migration and invasion of human hepatocellular carcinoma cells

The epithelial-mesenchymal transition (EMT) is an important cellular process during which polarized epithelial cells become motile mesenchymal cells, which promote cancer metastasis. Ginger, the rhizome of Zingiber officinale, is extensively used in cooking worldwide and also as a traditional medicinal herb with antioxidant, anti-inflammatory and anticancer properties. Several pungent compounds have been identified in ginger, including zingerone, which has anticancer potential. However, the role of zingerone in EMT is unclear. We investigated the synergistic effect of zingerone and its derivative on EMT. Transforming growth factor-beta 1 (TGF-β1) induces the EMT to promote hepatocellular carcinoma metastasis, including migration and invasion. To understand the repressive role of the combination of zingerone and its derivative (ZD 2) in hepatocellular carcinoma metastasis, we investigated the potential use of each compound of ginger, such as zingerone, ZD 2 and 6-shogaol, or the mixture of zingerone and ZD 2 (ZD 2-1) as inhibitors of TGF-β1 induced EMT development in SNU182 hepatocellular carcinoma cells in vitro. We show that ZD 2-1, but not zingerone, ZD 2 and 6-shogaol significantly increased expression of the epithelial marker E-cadherin and repressed Snail upregulation and expression of the mesenchymal marker N-cadherin during initiation of the TGF-β1 induced EMT. In addition, ZD 2-1 inhibited the TGF-β1 induced increase in cell migration and invasion of SNU182 hepatocellular carcinoma cells. Furthermore, ZD 2-1 significantly inhibited TGF-β1 regulated matrix metalloproteinase-2/9 and activation of Smad2/3. We also found that ZD 2-1 inhibited nuclear translocation of NF-κB, activation of p42/44 MAPK/AP1 signaling pathway in the TGF-β1 induced EMT. Our findings provide new evidence that combined treatment with ZD 2, novel zingerone derivative, and zingerone synergistically suppresses hepatocellular carcinoma metastasis in vitro by inhibiting the TGF-β1 induced EMT.

Upregulation of P2Y2 nucleotide receptor in human hepatocellular carcinoma cells

Objective

To examine if hypoxia inducible factor-1α (HIF-1α) can induce the upregulation of the purinergic receptor P2Y2 (P2Y2) and thereby promote the viability of human hepatocellular carcinoma (HCC) cells under hypoxic conditions.

Methods

Archival HCC tumour specimens and corresponding non-cancerous tissues were examined immunohistochemically for P2Y2 protein. A series of in vitro experiments were undertaken using HCC cell lines to determine the effect of hypoxia on HIF-1α and P2Y2 levels, the effect of HIF-1α upregulation on P2Y2 levels, and the effect of P2Y2 upregulation on cell viability under hypoxic conditions.

Results

Human HCC specimens were positive for P2Y2. Hypoxia and upregulated HIF-1α both upregulated the P2Y2 levels in HCC cell lines. P2Y2 upregulation using plasmid transfection resulted in enhanced cell viability under hypoxia. Treatment of HepG2 cells with the selective P2Y2 antagonist MRS2312 downregulated P2Y2 and reduced cell viability in five HCC cell lines. P2Y2 knockdown reduced HepG2 cell viability under hypoxia.

Conclusions

These present results suggest that HCC cells upregulate P2Y2 levels during hypoxia, which in turn promotes their growth. P2Y2 could be a potential therapeutic target for treating HCC.

The NKD1/Rac1 feedback loop regulates the invasion and migration ability of hepatocarcinoma cells

Hepatocellular carcinoma (HCC) is complicated by aggressive migration and invasion, which contribute to the increased mortality of HCC patients. The NKD1 protein is abnormally expressed in many neoplasms and plays an important role in tumor progression. However, the regulation and underlying molecular mechanisms of NKD1 in HCC cell invasion and migration remain poorly understood. In the present study, ectopic expression of NKD1 in HCC cells attenuated migration and invasion in vitro and in vivo by down-regulating Rac1 expression level and activity, which affected the HCC cell cytoskeleton and E-cadherin expression. Mechanistic studies showed that NKD1 interacted with Rac1 in the cytoplasm and promoted its degradation by the ubiquitin-proteasome pathway. Over-expression of Rac1 enhanced the transcription of the NKD1 gene and protein expression conversely owing to its negative regulation of EZH2. Analysis of clinical samples showed that abnormal expression of NKD1 and Rac1 was associated with the poor prognosis of HCC patients. In summary, our data indicate a new role for NKD1 as a regulator of HCC cell invasion and migration via a feedback loop involving Rac1.

Effect of liver regeneration on malignant hepatic tumors

Liver regeneration after major surgery may activate occult micrometastases and facilitate tumor growth, leading to liver tumor recurrence. Molecular changes during liver regeneration can provide a microenvironment that stimulates intrahepatic tumor propagation through alterations in cellular signaling pathways, where activation and proliferation of mature hepatocytes, hepatic progenitor cells, non-parenchymal liver cells might favor both liver regeneration and tumor growth. This review highlights recent advances of tumor growth and development in the regenerating liver, possible mechanisms and clinical implications.

Indolylmethylene benzo[h]thiazolo[2,3-b]quinazolinones: synthesis, characterization and evaluation of anticancer and antimicrobial activities

A series of novel 10-((1H-indol-3-yl)methylene)-7-aryl-7,10-dihydro-5H-benzo[h]thiazolo[2,3-b]quinazolin-9(6H)-ones (8a-t) have been synthesized in good yields by the reaction of benzo[h]quinazoline-2(1H)-thiones (4a-f) with 2-chloro-N-phenylacetamide (5) followed by Knoevenagel condensation with various indole-3-carbaldehydes (7a-d) under conventional method. All the synthesized compounds were characterized by spectral studies and screened for their in vitro anticancer and antimicrobial activities. Compound 8c has exhibited excellent activity against MCF-7 (breast cancer cell line) than the standard drug Doxorubicin. Compound 8d against both the cancer cell lines, 8q against MCF-7 and 8c, 8h against HepG2 have also shown good activity. Remaining compounds have shown moderate activity against both the cell lines. Antimicrobial activity revealed that, the compound 8q and 8t against Staphylococcus aureus and 8i, 8k, 8l, 8q &8t against Klebsiella pneumoniae have shown equipotent activity on comparing with the standard drug Streptomycin. Remaining compounds have shown significant antibacterial and comparable antifungal activities against all the tested microorganisms.

Induction of apoptosis and suppression of angiogenesis of hepatocellular carcinoma by HS-159, a novel phosphatidylinositol 3-kinase inhibitor

The phosphatidylinositol 3-kinase (PI3K) pathway plays a central role in cell proliferation and survival in human cancer and is emerging as an attractive therapeutic target. In this study, we synthesized a novel PI3Kα inhibitor, HS-159 [N-(5-(3-(3-cyanophenyl)imidazo[1,2-a]pyridin-6-yl)pyridin-3-yl)benzenesulfonamide] and evaluated its anticancer effects on Huh-7 human hepatocellular carcinoma (HCC) cells. HS-159 effectively inhibited the phosphorylation of downstream PI3K effectors such as Akt, mTOR and P70S6 kinases in a dose-dependent manner. This compound also induced apoptosis and increased the fraction of apoptotic cells in the sub-G1 phase as well as the levels of cleaved PARP, caspase-3 and -9. Furthermore, HS-159 decreased the expression of hypoxia inducible factor-1α and vascular endothelial growth factor which play important roles in angiogenesis. The anti-angiogenic effect of HS-159 was confirmed by the suppression of tube formation and migration of human umbilical vein endothelial cells in vitro. Collectively, our results demonstrate that HS-159 exhibited anticancer activities including the induction of apoptosis and inhibition of angiogenesis by blocking the PI3K/Akt pathway in Huh-7 cells. Therefore, we suggest that this drug may be potentially used for targeted HCC therapy.

Molecular mechanism inhibiting human hepatocarcinoma cell invasion by 6-shogaol and 6-gingerol

SCOPE

We previously demonstrated that 6-shogaol and 6-gingerol, two active compounds in ginger (Zingiber officinale), possess antiinvasive activity against highly metastatic hepatoma cells. The aims of this study were to evaluate the inhibitory effect and molecular mechanism underlying the transcription and translation of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA) in Hep3B cells as well as the antiangiogenic activity of 6-gingerol and 6-shogaol.

METHODS AND RESULTS

By gelatin zymography and luciferase reporter gene assays, we found that 6-gingerol and 6-shogaol regulate MMP-2/-9 transcription. Moreover, 6-gingerol directly decreased expression of uPA, but the 6-shogaol-mediated decrease in uPA was accompanied by up-regulation of plasminogen activator inhibitor (PAI)-1. 6-Gingerol and 6-shogaol concentrations of ≥ 10 μM and ≥ 2.5 μM, respectively, significantly inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) and PI3K/Akt signaling, the activation of NF-κB, and the translocation of NF-κB and STAT3. Incubation of 6-gingerol or 6-shogaol with human umbilical vein endothelial cells or rat aortas significantly attenuated tube formation.

CONCLUSION

6-Shogaol and 6-gingerol effectively inhibit invasion and metastasis of hepatocellular carcinoma through diverse molecular mechanisms, including inhibition of the MAPK and PI3k/Akt pathways and NF-κB and STAT3 activities to suppress expression of MMP-2/-9 and uPA and block angiogenesis.

Signal pathways associated with epithelial-mesenchymal transition in metastasis of primary hepatocelluar carcinoma

Epithelial-mesenchymal transition (EMT) is a phenomenon in which epithelial cells lose their epithelial characters and acquire mesenchymal characters. EMT can be seen in embryogenesis, organ fibrosis and tumor metastasis. EMT can be observed in metastasis of primary hepatocelluar carcinoma (HCC). This review focuses on several signal pathways associated with EMT, such as TGF-β, Wnt (wingless-type)/β-catenin, and Hedgehog signal pathways. Other factors involved in EMTs, such as NF-κB, Notch, miRNA, CHD1L, ARHGEF9, HBX, and extracellular matrix are also discussed in this article. A better understanding of the mechanism of EMT can help us find new targets for HCC treatment.

Prolonged Complete Response after GEMOX Chemotherapy in a Patient with Advanced Fibrolamellar Hepatocellular Carcinoma

The only currently validated treatment for advanced hepatocellular carcinoma (HCC) is sorafenib. However, sorafenib has been mainly studied in patients with HCC developed in cirrhotic liver. Chemotherapy might be more suitable for patients with HCC in non-cirrhotic liver. We report the case of a young woman with fibrolamellar HCC in a non-cirrhotic liver, with histologically proven metastatic ganglionary relapse after surgical resection of the primary tumour. Chemotherapy with gemcitabine and oxaliplatin (GEMOX regimen) achieved a complete response without relapse five years after discontinuation of chemotherapy. This exceptional case raises the question of clinical trials specifically designed for patients with HCC in non-cirrhotic liver.

HS-116, a novel phosphatidylinositol 3-kinase inhibitor induces apoptosis and suppresses angiogenesis of hepatocellular carcinoma through inhibition of the PI3K/AKT/mTOR pathway

The phosphatidylinositol 3-kinase (PI3K) pathway plays a central role in cell proliferation and survival of human cancers. As PI3K is active in many cancer patients, resulting in cancer development and progression, we developed an azaindole derivative, HS-116 as a novel PI3K inhibitor. This study aimed to clarify the anticancer effect of HS-116 in human hepatocellular carcinoma (HCC). To identify the effect of HS-116 on HCC cells, a PI3K assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, and Western blotting were conducted. IC(50) of HS-116 for PI3Kα was 31nM, and it effectively suppressed the phosphorylation of PI3K downstream factors such as AKT, mTOR, p70S6K, and 4EBP1. Also, HS-116 induced apoptosis by increasing the proportion of sub-G1 apoptotic cells from 1.8% to 35% and increasing the expressions of Bax, cleaved-caspase-3, and cleaved-PARP as well as decreasing the expression of Bcl-2. In addition, chromatin condensation and apoptotic bodies were detected in HS-116-treated HCC cells. Furthermore, HS-116 decreased protein expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF), and inhibited the tube formation and migration of human umbilical vein endothelial cells (HUVECs). In vivo, the ability of mice to vascularize subcutaneously implanted Matrigel plugs was diminished when the mice were treated with HS-116. These results show that HS-116 inhibits the PI3K/AKT/mTOR pathway via apoptosis and anti-angiogenesis in HCC cells. We suggest that HS-116 may be an effective novel therapeutic candidate against HCC.

Anti-hepatocellular carcinoma activity using human HepG2 cells and hepatotoxicity of 6-substituted methyl 3-aminothieno[3,2-b]pyridine-2-carboxylate derivatives: in vitro evaluation, cell cycle analysis and QSAR studies

Hepatocellular carcinoma (HCC) is a highly complex cancer, resistant to commonly used treatments and new therapeutic agents are urgently needed. A total of thirty-two thieno[3,2-b]pyridine derivatives of two series: methyl 3-amino-6-(hetero)arylthieno[3,2-b]pyridine-2-carboxylates (1a-1t) and methyl 3-amino-6-[(hetero)arylethynyl]thieno[3,2-b]pyridine-2-carboxylates (2a-2n), previously prepared by some of us, were evaluated as new potential anti-HCC agents by studying their in vitro cell growth inhibition on human HepG2 cells and hepatotoxicity using a porcine liver primary cell culture (PLP1). The presence of amino groups linked to a benzene moiety emerges as the key element for the anti-HCC activity. The methyl 3-amino-6-[(3-aminophenyl)ethynyl]thieno[3,2-b]pyridine-2-carboxylate (2f) is the most potent compound presenting GI(50) values on HepG2 cells of 1.2 μM compared to 2.9 μM of the positive control ellipticine, with no observed hepatotoxicity (PLP1 GI(50) > 125 μM against 3.3 μM of ellipticine). Moreover this compound changes the cell cycle profile of the HepG2 cells, causing a decrease in the % of cells in the S phase and a cell cycle arrest in the G2/M phase. QSAR studies were also performed and the correlations obtained using molecular and 1D descriptors revealed the importance of the presence of amino groups and hydrogen bond donors for anti-HCC activity, and hydrogen bond acceptors for hepatotoxicity. The best correlations were obtained with 3D descriptors belonging to different subcategories for anti-HCC activity and hepatotoxicity, respectively. These results point to different molecular mechanisms of action of the compounds in anti-HCC activity and hepatotoxicity. This work presents some promising thieno[3,2-b]pyridine derivatives for potential use in the therapy of HCC. These compounds can also be used as scaffolds for further synthesis of more potent analogs.

Functional significance of the ATP-binding cassette transporter B6 in hepatocellular carcinoma

ABCB6 is a mitochondrial transporter that regulates porphyrin biosynthesis. ABCB6 expression is upregulated in hepatocellular carcinoma (HCC) but the significance of this upregulation to HCC is not known. In the present study, we investigated: 1) ABCB6 expression in 18 resected human hepatocellular carcinoma (HCC) tissues and 3 human hepatoma cell lines; 2) pattern of ABCB6 expression during liver disease progression; and 3) functional significance of ABCB6 expression to HCC using the hepatoma cell line Huh7. ABCB6 expression was determined by real-time quantitative reverse transcription-polymerase chain reaction and western blotting. ABCB6 expression was upregulated in all the HCC specimens and the three-hepatoma cell lines. Increased ABCB6 expression correlated with liver disease progression with the pattern of expression being HCC > cirrhosis > steatosis. Small hairpin RNA (shRNA)-mediated knockdown of ABCB6 in Huh7 cells lead to decreased cellular proliferation and colony formation. Attenuation of ABCB6 expression did not affect Huh7 apoptosis but lead to a delay in G2/M phase of the cell cycle. In contrast, ABCB6 overexpression resulted in increased growth and proliferation of Huh7 cells. Since ABCB6 expression is induced in multiple tumor types we explored the role of ABCB6 in other cancer cells. ShRNA mediated knockdown of ABCB6 in HEK293 and K562 cells reduced cellular proliferation leading to a delay in G2/M phase, while ABCB6 overexpression promoted cell growth and proliferation. Collectively, these findings, obtained by loss of function and gain of function analysis, suggest that ABCB6 plays a role in cell growth and proliferation by targeting the cell cycle.

The role of signaling pathways in the development and treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly prevalent, treatment-resistant malignancy with a multifaceted molecular pathogenesis. Current evidence indicates that during hepatocarcinogenesis, two main pathogenic mechanisms prevail: (1) cirrhosis associated with hepatic regeneration after tissue damage caused by hepatitis infection, toxins (for example, alcohol or aflatoxin) or metabolic influences, and (2) mutations occurring in single or multiple oncogenes or tumor suppressor genes. Both mechanisms have been linked with alterations in several important cellular signaling pathways. These pathways are of interest from a therapeutic perspective, because targeting them may help to reverse, delay or prevent tumorigenesis. In this review, we explore some of the major pathways implicated in HCC. These include the RAF/MEK/ERK pathway, phosphatidylinositol-3 kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, WNT/beta-catenin pathway, insulin-like growth factor pathway, hepatocyte growth factor/c-MET pathway and growth factor-regulated angiogenic signaling. We focus on the role of these pathways in hepatocarcinogenesis, how they are altered, and the consequences of these abnormalities. In addition, we also review the latest preclinical and clinical data on the rationally designed targeted agents that are now being directed against these pathways, with early evidence of success.

Comparison of efficacy and toxicity of short-course carbon ion radiotherapy for hepatocellular carcinoma depending on their proximity to the porta hepatis

BACKGROUND AND PURPOSE

To compare the efficacy and toxicity of short-course carbon ion radiotherapy (C-ion RT) for patients with hepatocellular carcinoma (HCC) in terms of tumor location: adjacent to the porta hepatis or not.

MATERIALS AND METHODS

The study consisted of 64 patients undergoing C-ion RT of 52.8 GyE in four fractions between April 2000 and March 2003. Of these patients, 18 had HCC located within 2 cm of the main portal vein (porta hepatis group) and 46 patients had HCC far from the porta hepatis (non-porta hepatis group). We compared local control, survival, and adverse events between the two groups.

RESULTS

The 5-year overall survival and local control rates were 22.2% and 87.8% in the porta hepatis group and 34.8% and 95.7% in the non-porta hepatis group, respectively. There were no significant differences (P=0.252, P=0.306, respectively). Further, there were no significant differences in toxicities. Biliary stricture associated with C-ion RT did not occur.

CONCLUSIONS

Excellent local control was obtained independent of tumor location. The short-course C-ion RT of 52.8 GyE in four fractions appears to be an effective and safe treatment modality in the porta hepatis group just as in the non-porta hepatis group.

Compensatory enlargement of the liver after treatment of hepatocellular carcinoma with carbon ion radiotherapy - relation to prognosis and liver function

BACKGROUND AND PURPOSE

To examine whether liver volume changes affect prognosis and hepatic function in patients treated with carbon ion radiotherapy (CIRT) for hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

Between April 1995 and March 2003, among the cases treated with CIRT, 43 patients with HCC limited to the right hepatic lobe were considered eligible for the study. The left lateral segment was defined as the non-irradiated region. Liver volume was measured using contrast CT at 0, 3, 6, and 12 months after CIRT. We examined serum albumin, prothrombin activity, and total bilirubin level as hepatic functional reserve.

RESULTS

After CIRT, the non-irradiated region showed significant enlargement, and enlarged volume of this region 3 months after CIRT 50 cm(3) was a prognostic factor. The 5-year overall survival rates were 48.9% in the larger enlargement group (enlarged volume of non-irradiated region 3 months after CIRT > or =50 cm(3)) and 29.4% in the smaller enlargement group (as above, <50 cm(3)). The larger enlargement group showed better hepatic functional reserve than the smaller enlargement group 12 months after CIRT.

CONCLUSIONS

This study suggests that compensatory enlargement in the non-irradiated liver after CIRT contributes to the improvement of prognosis.

Granulin-epithelin precursor as a therapeutic target for hepatocellular carcinoma

Primary liver cancer, hepatocellular carcinoma (HCC), is the fifth most common cancer and the third leading cancer killer in the world. There is no effective therapeutic option for most HCC patients. A new therapeutic strategy is essential. Granulin-epithelin precursor (GEP, also called progranulin, acrogranin, or PC-derived growth factor) was identified as a potential therapeutic target for HCC from our earlier genome-wide expression profiles. We aimed to conduct a detailed investigation with in vitro and animal experiments. We developed the anti-GEP monoclonal antibody (mAb), and examined its effect on hepatoma cells and normal liver cells in vitro. A nude mice model transplanted with human HCC was used to investigate if anti-GEP mAb can inhibit tumor growth in vivo. We demonstrated that anti-GEP mAb inhibited the growth of hepatoma cells but revealed no significant effect on normal liver cells. In the nude mice model transplanted with human HCC, anti-GEP mAb decreased the serum GEP level and inhibited the growth of established tumors in a dose-dependent manner. The anti-GEP mAb reduced tumor cell proliferation via the p44/42 MAPK and Akt pathways, and reduced tumor angiogenesis to deprive the nutrient supply with reduced microvessel density and tumor vascular endothelial growth factor level.

CONCLUSION

We have shown that anti-GEP antibody can inhibit HCC growth, providing evidence that GEP is a therapeutic target for HCC treatment.

Inhibition of hepatocellular carcinoma invasion by suppression of claudin-10 in HLE cells

Previously, we showed that down-regulation of claudin-10 (CLDN-10) in hepatocellular carcinoma is associated with prolonged disease-free survival after curative surgery. Claudins are important tight junction components. Increasing evidence shows that claudins are involved in cancer progression but each member of claudins is specifically expressed in a variety of malignancies. The biological role of CLDN-10 in hepatocellular carcinoma is unexplored. In the current study, we investigated the CLDN-10 function in two different hepatocellular carcinoma cell lines by in vitro assays with the CLDN-10 overexpression and small interfering RNA-mediated knockdown transfectants. We observed that overexpression of CLDN-10 conferred malignant phenotypes to hepatocellular carcinoma cells, Hep3B, which lack CLDN-10 expression, by promoting cancer cell survival, motility, and invasiveness. More importantly, matrix metalloproteinase 2 (MMP2) was up-regulated. Increase in mRNA transcription and protein expression of membrane type 1-MMP (MT1-MMP) was also observed in the CLDN-10 transfectants, where MT1-MMP was a protease shown to promote intrahepatic metastasis in hepatocellular carcinoma in our earlier study. In addition, CLDN-1, CLDN-2, and CLDN-4 was up-regulated in CLDN-10 overexpression transfectants, indicating that the expression of CLDN-10 in cancer cells might affect the expression levels of its family members. On the contrary, small interfering RNA-based knockdown of CLDN-10 in HLE, an invasive cell line with high level of CLDN-10 expression, abolished invasion and strongly decreased activation of MMPs and claudin members expression. These findings showed that CLDN-10 is functionally involved in hepatocellular carcinoma invasion and is a potential target for hepatocellular carcinoma therapy.

A comparison of chemoembolization endpoints using angiographic versus transcatheter intraarterial perfusion/MR imaging monitoring

PURPOSE

Transcatheter arterial chemoembolization (TACE) is an established treatment for unresectable liver cancer. This study was conducted to test the hypothesis that angiographic endpoints during TACE are measurable and reproducible by comparing subjective angiographic versus objective magnetic resonance (MR) endpoints of TACE.

MATERIALS AND METHODS

The study included 12 consecutive patients who presented for TACE for surgically unresectable HCC or progressive hepatic metastases despite chemotherapy. All procedures were performed with a dedicated imaging system. Angiographic series before and after TACE were reviewed independently by three board-certified interventional radiologists. A subjective angiographic chemoembolization endpoint (SACE) classification scheme, modified from an established angiographic grading system in the cardiology literature, was designed to assist in reproducibly classifying angiographic endpoints. Reproducibility in SACE classification level was compared among operators, and MR imaging perfusion reduction was compared with SACE levels for each observer.

RESULTS

Twelve patients successfully underwent 15 separate TACE sessions. SACE levels ranged from I through IV. There was moderate agreement in SACE classification (kappa = 0.46 +/- 0.12). There was no correlation between SACE level and MR perfusion reduction (r = 0.16 for one operator and 0.02 for the other two).

CONCLUSIONS

Angiographic endpoints during TACE vary widely, have moderate reproducibility among operators, and do not correlate with functional MR imaging perfusion endpoints. Future research should aim to determine ideal angiographic and functional MR imaging endpoints for TACE according to outcome measures such as imaging response, pathologic response, and survival.

Des-gamma-carboxyl prothrombin-promoted vascular endothelial cell proliferation and migration

Des-gamma-carboxyl prothrombin (DCP) is a well recognized tumor marker for hepatocellular carcinoma. Previously, we have demonstrated that DCP stimulates cell proliferation in hepatocellular carcinoma cell lines through Met-Janus kinase 1 signal transducer and activator of transcription 3 signaling pathway. In the present study, we demonstrated that DCP induces both cell proliferation and migration in human umbilical vein endothelial cells. DCP was found to bind with the kinase insert domain receptor (KDR), alternatively referred to as vascular endothelial growth factor receptor-2. Furthermore, DCP induced autophosphorylation of KDR and its downstream effector phospholipase C-gamma and mitogen-activated protein kinase (MAPK). To support these results, we showed that DCP-induced cell proliferation and cell migration were inhibited by KDR short interfering RNA, KDR kinase inhibitor, or MAPK inhibitor. In conclusion, these results indicate that DCP is a novel type of vascular endothelial growth factor that possesses potent mitogenic and migrative activities.

Rapamycin inhibits cell growth by induction of apoptosis on hepatocellular carcinoma cells in vitro

BACKGROUND

Rapamycin, isolated from Streptomyces hygroscopicus, is recently reported to have immunosuppressant and anti-tumor effects on a large variety of cancers. To date, no detailed data are available about the effects of rapamycin on hepatocellular carcinoma cells.

OBJECTIVE

In this study, the anti-proliferation effects of rapamycin on hepatocellular carcinoma cells BEL-7402 and HepG-2 in vitro were studied.

METHODS

Cell viability was assessed by MTT assay and [3H]-thymidine uptake, cell apoptosis was observed by Hoechst 33258 staining and flow cytometry (FCM). The variation of caspase-3 and apoptotic related genes was assayed by Western blotting, cell mitochondrial membrane potential was also investigated by using standard methods.

RESULTS

Rapamycin could inhibit the growth of hepatocellular carcinoma cells and cause apoptosis significantly; the suppression was both in time- and dose-dependent manner, marked morphological changes of cell apoptosis were observed very clearly by Hoechst 33258 staining. Rapamycin exhibits induction apoptosis by activation of caspase-3 and disruption of the mitochondrial membrane potential on hepatocellular carcinoma cells in vitro. Western blotting analysis demonstrated that anti-apoptotic protein Bcl-2 was down-regulated while pro-apoptotic protein Bcl-xl up-regulated remarkably in a time-dependent manner when apoptosis occurred.

CONCLUSION

Rapamycin has significant anti-proliferation effect by induction of apoptosis via activation of caspase-3 and disruption of mitochondrial membrane potential, as well as by down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bcl-xl on hepatocellular carcinoma cells. The data provide a potential mechanism for rapamycin-induced apoptosis in hepatocellular carcinoma cells, suggesting that rapamycin may serve as both an effective adjunctive reagent for the treatment of residual cancer cells and immunosuppressant after liver transplantation of hepatocellular carcinoma, and that in vivo anti-cancer effects as well as its potential clinical effectiveness need further investigation.

Recurrence after liver resection for hepatocellular carcinoma: risk factors, treatment, and outcomes

BACKGROUND

Tumor recurrence remains the major cause of death after curative resection for hepatocellular carcinoma (HCC). The purpose of this study was to identify risk factors for the recurrence of HCC and to examine long-term outcomes after resection.

METHODS

From July 1992 to July 2004, 193 consecutive patients who underwent hepatic resection as primary therapy with curative intent for HCC were included in this single-center analysis. The perioperative mortality rate was 5%. Time to recurrence (disease-free survival) and overall survival were determined by Kaplan-Meier analysis. Demographic, tumor, and treatment characteristics were tested for their prognostic significance by univariate and multivariate analysis with the log-rank test and the Cox proportional hazards model, respectively.

RESULTS

Median overall survival for the entire cohort was 71 +/- 11 months; disease-free survival was 34 months (range, 1-149 months). After a median follow-up time of 34 months, 98 patients (51%) experienced recurrent cancer; initial tumor recurrence was confined to the liver in 86 patients (88%). With the use of multivariate analysis, preoperative vascular invasion detected on radiologic imaging studies; postoperative vascular invasion found on pathologic assessment, and intermediate and poor tumor differentiation and tumor size and number were significant predictors of disease-free survival. Of the 98 patients who had tumor recurrence, 53 patients (54%) underwent additional therapy (ablation, 31 patients; re-resection, 11 patients; transarterial chemoembolization, 8 patients; liver transplantation, 3 patients) with improvement in survival.

CONCLUSION

Despite recurrences in >50% of patients, long-term survival can be achieved after resection of HCC. Identification of risk factors, close follow-up evaluation, and early detection are mandatory because recurrences that are confined to the liver may be amenable to treatment with an additional survival benefit.

Radiochromic Films for Improved Evaluation of Patient Dose in Liver Interventions

PURPOSE

To investigate a method for evaluation of the maximum skin dose (MSD) of radiation in patients undergoing interventional radiology procedures in the liver.

MATERIALS AND METHODS

Transarterial chemoembolization, transarterial embolization, portal vein embolization, and biliary interventions were the procedures considered in this study. Ninety procedures in 70 patients were studied. The complexity of the biliary interventions was taken into account during the analysis. The MSD was measured with use of GAF chromic XR type R films, whereas the dose-area product (DAP) was measured by a transmission chamber.

RESULTS

The MSD was measured in a group of 19 patients. The coefficient of the interpolation line between the skin dose and the DAP (0.0051 cm(-2)) was determined. An approximated value of MSD from the DAP for the remaining 71 procedures was estimated by means of an interpolation line. The mean MSD in the endovascular procedures was 4.4 Gy; for the three different levels of complexity of the biliary procedures, the mean MSDs were 0.4, 1.2, and 3 Gy, respectively.

CONCLUSIONS

Radiochromic films are an easy-to-use and efficient method for measuring skin entrance radiation dose and have the advantage of providing information on the MSD as well as the distribution of radiation to the skin. In light of these results, the authors suggest recording the dose for biliary and endovascular procedures as indicated by the International Commission on Radiological Protection and the United States Food and Drug Administration.

Is there a role for immunotherapy in hepatocellular carcinoma?

Incidence of hepatocellular carcinoma has been rising in the last two decades because of the wide exposure to hepatitis C virus during 1960s and 1970s. Improvement in treatment has been achieved by local ablative therapies, however because of early recurrence and lack of effective chemotherapies, alternative treatments based on stimulation of the anti-tumour immune response could represent new strategies to control hepatocellular carcinoma spread and recurrence. Proof of principle of an effective immunotherapy has been achieved for other solid tumours such as melanoma and several results could be transferred to the immunotherapy of hepatocellular carcinoma. Specific tumour antigens have been identified in hepatocellular carcinoma, such as cancer testis antigens expressed in a large part of hepatocellular carcinomas and alpha-fetoprotein that has been already employed in clinical trials demonstrating immunogenicity without however significant clinical efficacy. Better results have been achieved by non-antigen-specific immunotherapies that demonstrated improvement in recurrence and recurrence-free survival in patients undergoing surgical resection for hepatocellular carcinoma. Passive immunotherapy and targeted therapies blocking tumour cell receptors or enzymatic pathways are already in the clinic for other malignancies and the near future will see these new treatments applied to hepatocellular carcinoma patients along with the development of efficacious active immunotherapies aimed at reducing disease recurrence and improving survival.