Interleukin 8 in human hepatocellular carcinoma correlates with cancer cell invasion of vessels but not with tumor angiogenesis

Low-dose metformin suppresses hepatocellular carcinoma metastasis via the AMPK/JNK/IL-8 pathway

BACKGROUND AND OBJECTIVES

Metformin, an oral hypoglycemic drug, has been suggested to possess antitumour activity in several types of cancers. Additionally, interleukin-8 (IL-8) has been reported to be involved in the development and metastasis of many cancers. However, the effect of metformin on IL-8 expression in hepatocellular carcinoma (HCC) remains unclear. Therefore, this study aimed to investigate whether metformin could inhibit IL-8 expression to exert an inhibitory effect on HCC progression.

MATERIALS AND METHODS

The IL-8 levels were measured in the plasma of 159 HCC patients (86 men, 73 women; average age 56 years) and in the culture supernatant of HCC cells (Hep3B and HuH7) using flow cytometry. In addition, the protein expression levels of IL-8 were also validated by the Human Protein Atlas (HPA) database. The prognostic value of IL-8 was evaluated using the Kaplan-Meier Plotter database. The association between IL-8 expression and immune checkpoints was estimated using the TIMER and The Cancer Genome Atlas (TCGA) databases. What's more, bioinformatics analysis, western blotting, and transwell assays were conducted to illustrate the molecular mechanism of metformin (≤1 mM) on IL-8 in HCC.

RESULTS

IL-8 expression was found to be increased in the plasma of HCC patients, which is consistent with the expression of IL-8 in HCC cells and tissues. High expression of IL-8 was significantly related to poor prognosis. In addition, IL-8 was positively correlated with immune checkpoints in HCC. Notably, we found that low-dose metformin could inhibit the secretion of IL-8 by HCC cells and the migration of HCC cells. Mechanistically, low-dose metformin significantly suppresses HCC metastasis mainly through the AMPK/JNK/IL-8/MMP9 pathway.

CONCLUSION

The results indicate that low-dose metformin can inhibit HCC metastasis by suppressing IL-8 expression. Targeting the AMPK/JNK/IL-8 axis may be a promising treatment strategy for patients with HCC metastasis.

Selective Internal Radiotherapy Alters the Profiles of Systemic Extracellular Vesicles in Hepatocellular Carcinoma

Incidence of hepatocellular carcinoma (HCC) is increasing globally. Radioembolization (RE)/selective internal radiotherapy (SIRT) is a promising treatment for inoperable HCC. RE triggers an immune response, involving extracellular vesicles (EVs) which are crucial for cell communication and tumor development. This study explores EV immune profiles and origins in patients with inoperable HCC before and after SIRT/RE. Blood samples from 50 HCC-patients treated with SIRT/RE were collected before and after therapy to determine cytokines and isolate EVs using size exclusion chromatography. The dynamic range and EV quality required for detecting variations in surface markers were assessed. Thirty-seven EV surface markers were analyzed using flow cytometry and correlated with clinical parameters. Several immunological markers (CD4, CD2, CD40, CD45, CD49e, CD69, CD209-EVs) were present in the circulation of HCC patients. These markers positively correlated with therapy response and survival. Conversely, B cell CD20, endothelial cell CD146, platelet CD49e, and CD41b EV markers negatively correlated with 60-day survival. Elevated levels of IL-6 and IL-8 before therapy correlated negatively with patient survival, coinciding with a positive correlation with CD20-positive EVs. Plasma EVs from HCC patients exhibit immunological, cancer, and coagulation markers, including potential biomarkers (CD4, CD20, CD49e, CD146). These may enhance our understanding of cancer biology and facilitate SIRT therapy monitoring.

Chemokines in hepatocellular carcinoma: a meta-analysis

Accumulating evidence suggests that chemokines may play an important role in the formation and mediating of the immune microenvironment of hepatocellular carcinoma (HCC). The purpose of this meta-analysis was to explore the differences in blood or tissues chemokines concentrations between HCC patients and controls. Online databases, namely PubMed, Web of Science, Embase and Cochrane Library, were systematically searched for relevant articles published on or before 15 January 2020. Standardized mean differences (SMDs) with corresponding 95% confidence intervals of the chemokines concentrations were calculated as group differences between the HCC patients and the controls. Sixty-five studies met the inclusion criteria for the meta-analysis. Altogether they consisted of 26 different chemokines compared between 5828 HCC patients and 4909 controls; and 12 different chemokines receptors compared between 2053 patients and 2285 controls. The results of meta-analysis indicated that concentrations of CCL20, CXCL8 and CXCR4 in the HCC patients were significantly higher than those in the controls (SMD of 6.18, 1.81 and 1.04, respectively). Therefore, higher concentration levels of CCL20, CXCL8 and CXCR4 may indicate the occurrence of HCC Future research should explore the putative mechanisms underlying this linkage. Meanwhile, attempts can be made to replicate the existing findings in prospective cohort populations and explore the cause-and-effect relationships pertaining to this linkage in order to develop new diagnostic and therapeutic strategies for HCC.

TAZ-regulated expression of IL-8 is involved in chemoresistance of hepatocellular carcinoma cells

Chemotherapy resistance is one of the major challenges for the treatment of hepatocellular carcinoma (HCC). In order to investigate the mechanisms involved in chemoresistance of HCC, we established cisplatin (CDDP) and doxorubicin (Dox) resistant HCC cells. The expression of transcriptional coactivator with PDZ-binding motif (TAZ), one of the major downstream effectors of Hippo pathway, was upregulated in chemoresistant HCC cells. Targeted inhibition of TAZ via its siRNAs can restore CDDP and Dox sensitivity of chemoresistant HCC cells. The upregulation of TAZ increased the expression of IL-8 in HCC/CDDP and HCC/Dox cells. Recombinant IL-8 (rIL-8) antagonized the increased chemosensitivity mediated by TAZ knockdown. Mechanistically, TAZ can directly bind with the promoter of IL-8 to activate its transcription in chemoresistant HCC cells. Collectively, our data showed that TAZ-regulated expression of IL-8 was involved in chemoresistance of HCC cells. It indicated that targeted inhibition of TAZ/IL-8 axis might be helpful to improve chemotherapy efficiency for HCC.

CPAP promotes angiogenesis and metastasis by enhancing STAT3 activity

Centrosomal P4.1-associated protein (CPAP) is overexpressed in hepatocellular carcinoma (HCC) and positively correlated with recurrence and vascular invasion. Here, we found that CPAP plays an important role in HCC malignancies. Functional characterization indicated that CPAP overexpression increases tumor growth, angiogenesis, and metastasis ex vivo and in vivo. In addition, overexpressed CPAP contributes to sorafenib resistance. Mechanical investigation showed that the expression level of CPAP is positively correlated with activated STAT3 in HCC. CPAP acts as a transcriptional coactivator of STAT3 by directly binding with STAT3. Interrupting the interaction between CPAP and STAT3 attenuates STAT3-mediated tumor growth and angiogenesis. Overexpression of CPAP upregulates several STAT3 target genes such as IL-8 and CD44 that are involved in angiogenesis, and CPAP mRNA expression is positively correlated with the levels of both mRNAs in HCC. Knocked-down expression of CPAP impairs IL-6-mediated STAT3 activation, target gene expression, cell migration, and invasion abilities. IL-6/STAT3-mediated angiogenesis is significantly increased by CPAP overexpression and can be blocked by decreased expression of IL-8. Our findings not only shed light on the importance of CPAP in HCC malignancies, but also provide potential therapeutic strategies for inhibiting the angiogenesis pathway and treating metastatic HCC.

Plumbagin Restrains Hepatocellular Carcinoma Angiogenesis by Stromal Cell-Derived Factor (SDF-1)/CXCR4-CXCR7 Axis

BACKGROUND Anti-angiogenic therapy has recently emerged as a highly promising therapeutic strategy for treating hepatocellular carcinoma (HCC). MATERIAL AND METHODS We assessed cellular proliferation, invasion, and activation of growth factors (VEGF and IL-8) with SDF-1 induced in the hepatocellular carcinoma cell line SMMC-7721, and this progression was limited by plumbagin (PL). The human umbilical vein endothelial cell line HUVEC was co-cultured with SDF-1-induced SMMC-7721, and the expressions of CXCR7, CXCR4, and PI3K/Akt pathways after PL treatment were detected by RT-PCR and Western blot analysis. RESULTS The treatment of the hepatoma cell line SMMC-7721 with SDF-1 resulted in enhanced secretion of the angiogenic factors, IL-8 and VEGF, and shows that these stimulatory effects are abolished by PL. The study further demonstrated that PL not only abolishes SDF-1-induced formation of endothelial tubes, but also inhibits expression of CXCR4 and CXCR7, and partially prevents activation of angiogenic signaling pathways. CONCLUSIONS The effect of PL on the SDF-1-CXCR4/CXCR7 axis has become an attractive target for inhibiting angiogenesis in hepatoma cells. Our results provide more evidence for the clinical application of PL as part of traditional Chinese medicine in modern cancer treatment.

A systematic review and meta-analysis of evaluation of serum interleukin 8 levels in hepatocellular carcinoma

Aim of the study

To estimate serum interleukin 8 (IL-8) level in patients with hepatocellular carcinoma (HCC) compared to controls and patients with chronic hepatitis (CH) and liver cirrhosis (LC).

Material and methods

Three databases, i.e. PubMed, Web of Science, and Scopus, were searched up to November 2017 without language restriction. The mean difference (MD) and 95% confidence interval (CI) were used by a random-effects analysis in RevMan version 5.3, and sensitivity analysis was performed as the secondary analysis.

Results

Out of 239 studies found, 10 studies recruiting 659 HCC patients, 237 controls, 357 patients with LC, and 48 patients with CH were included and analyzed in the meta-analysis. The pooled MDs were 39.48 (95%CI: 152.31, 406.47, p < 0.00001), 21.32 (95% CI: –6.04, 48.68, p = 0.13), and 36.46 (95% CI: 21.77, 51.15, p < 0.00001) in the patients with HCC compared to the controls, the patients with LC and those with CH, respectively.

Conclusions

An elevated serum IL-8 level in the HCC patients compared to the three other groups showed an increased risk for this cytokine in HCC patients. Therefore, this interleukin can be used as a new biomarker replacing alpha-fetoprotein (AFP) or as a clinical assay for evaluation of the pathogenesis and probably the progression or development of HCC.

Higher serum interleukin-17A levels as a potential biomarker for predicting early disease progression in patients with hepatitis B virus-associated advanced hepatocellular carcinoma treated with sorafenib

BACKGROUND

Although sorafenib is the only available drug with proven efficacy for patients with advanced hepatocellular carcinoma (HCC), the clinical efficacy of sorafenib is variable and unpredictable. The aim of the current study was to identify potential serum biomarkers predicting cancer progression and overall survival (OS) in patients with hepatitis B virus (HBV)-related advanced HCC treated with sorafenib.

METHODS

Thirty-four patients with HBV-related advanced HCC (modified Union for International Cancer Control [UICC] stage IVa or IVb) treated with sorafenib for more than 4weeks were retrospectively enrolled. Using a Luminex 200 system, 11 cytokines including interleukin-17A (IL-17A) were measured in baseline serum samples prior to sorafenib administration. Several clinical factors and the serum concentrations of the 11 cytokines were analyzed using Cox regression analysis.

RESULTS

In the analysis of progression-free survival (PFS), older age (year; hazard ratio [HR]=1.07; 95% confidence interval [CI]=1.00-1.15; P=0.046) and higher baseline serum IL-17A level (>1.94pg/mL; HR=19.96; 95% CI=3.32-119.86; P=0.001) were identified as significant risk factors for early progression with good predictive power (Harrell's C=0.817, standard error estimates (se)=0.085). In the analysis of OS, higher Child-Pugh score (>5; HR=2.35, 95% CI=1.09-5.10, P=0.030) and lower serum baseline fibroblast growth factor-2 level (≤20.57pg/mL; HR=3.24, 95% CI=1.22-8.60, P=0.018) were identified as negative predictive factors for OS, even though the model did not have significant predictive power (Harrell's C=0.634, se=0.062).

CONCLUSION

A higher serum IL-17A level is a potential biomarker for predicting poor PFS in patients with HBV-related advanced HCC treated with sorafenib.

Anticancer effect of luteolin is mediated by downregulation of TAM receptor tyrosine kinases, but not interleukin-8, in non-small cell lung cancer cells

TAM receptor tyrosine kinases (RTKs), Tyro3, Axl and MerTK, transduce diverse signals responsible for cell survival, growth, proliferation and anti-apoptosis. In the present study, we demonstrated the effect of luteolin, a flavonoid with antioxidant, anti-inflammatory and anticancer activities, on the expression and activation of TAM RTKs and the association with its cytotoxicity in non-small cell lung cancer (NSCLC) cells. We observed the cytotoxic effect of luteolin in parental A549 and H460 cells as well as in cisplatin-resistant A549/CisR and H460/CisR cells. Exposure of these cells to luteolin also resulted in a dose‑dependent decrease in clonogenic ability. Next, luteolin was found to decrease the protein levels of all three TAM RTKs in the A549 and A549/CisR cells in a dose‑dependent manner. In a similar manner, in H460 and H460/CisR cells, the protein levels of Axl and Tyro3 were decreased following luteolin treatment. In addition, Axl promoter activity was decreased by luteolin, indicating that luteolin suppresses Axl expression at the transcriptional level. We next found that luteolin abrogated Axl phosphorylation in response to growth arrest-specific 6 (Gas6), its ligand, implying the inhibitory effect of luteolin on Gas6-induced Axl activation. Ectopic expression of Axl was observed to attenuate the antiproliferative effect of luteolin, while knockdown of the Axl protein level using a gold nanoparticle-assisted gene delivery system increased its cytotoxicity. In contrast to the inhibitory effect of luteolin on the expression of TAM RTKs, interleukin-8 (IL-8) production was not decreased by luteolin in H460 and H460/CisR cells, while IL-8 production/cell was increased. Collectively, our data suggest that TAM RTKs, but not IL-8, are promising therapeutic targets of luteolin to abrogate cell proliferation and to overcome chemoresistance in NSCLC cells.

Knockdown of HIF-1α and IL-8 induced apoptosis of hepatocellular carcinoma triggers apoptosis of vascular endothelial cells

A local hypoxic microenvironment is one of the most important characteristics of solid tumors. Hypoxia inducible factor-1α (HIF-1α) and Interleukin-8 (IL-8) activate tumor survival from hypoxic-induced apoptosis in each pathway. This study aimed to evaluate whether knockdown of HIF-1α and IL-8 induced apoptosis of the hepatocellular carcinoma (HCC) and endothelial cell lines. HCC cell lines were infected with adenovirus-expressing shRNA for HIF-1α and IL-8 and maintained under hypoxic conditions (1% O2, 24 h). The expression levels of HIF-1α and both apoptotic and growth factors were examined by real-time quantitative PCR and western blot. We also investigated apoptosis by TUNEL assay (FACS and Immunofluorescence) and measured the concentration of cytochrome C. Inhibition of HIF-1α and IL-8 up-regulated the expression of apoptotic factors while downregulating anti-apoptotic factors simultaneously. Knockdown of HIF-1α and IL-8 increased the concentration of cytochrome C and enhanced DNA fragmentation in HCC cell lines. Moreover, culture supernatant collected from the knockdown of HIF-1α and IL-8 in HCC cell lines induced apoptosis in human umbilical vein endothelial cells under hypoxia, and the expression of variable apoptotic ligand increased from HCC cell lines, time-dependently. These data suggest that adenovirus-mediated knockdown of HIF-1α and IL-8 induced apoptosis in HCC cells and triggered apoptosis of vascular endothelial cells.

Type conversion of secretomes in a 3D TAM2 and HCC cell co-culture system and functional importance of CXCL2 in HCC

Macrophages play important roles in the tumor microenvironment, driving cancer progression and metastasis, particularly in hepatocellular carcinoma (HCC). However, few studies have assessed the exact secretome composition in HCC. In the present study, the impact of different phenotype of macrophages on HCC cells was investigated. Alternatively activated macrophages (M2) were found to significantly increase the proliferation, migration, and invasion abilities of SMMC7721 cells (all P < 0.05). M2 were then co-cultured with SMMC7721 cells to reconstruct the tumor microenvironment. Conditioned medium from 3D single cultures of M2, SMMC7721 cells, and their co-culture system were analyzed using quantitative proteomics via iTRAQ labeling combined with mass spectrometric analysis. Secretome analysis revealed a total of 159 differential secreted proteins in the co-culture system compared to the single culture systems, with 63 being up-regulated (>1.3-fold) and 96 down-regulated (<0.7-fold). CXCL2 was confirmed to have higher expression in the co-culture system and HCC tissues, and was selected for further investigation. Functional effects data suggested that recombinant human CXCL2 significantly enhanced the migration, invasion ability of SMMC7721 cells, and weakened adhesion ability. While CXCL2 neutralization and CXCR2 blockage significantly inhibited the effects of CXCL2 on SMMC7721 cells, indicating that CXCL2 may play pivotal role in HCC metastasis.

CD146 promotes metastasis and predicts poor prognosis of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. Recurrence and metastasis after curative resection remain critical obstacles in HCC treatment. CD146 predicted poor prognosis of a variety of cancers including melanoma, breast tumors, prostate cancer, and gastric cancer. However, the role of CD146 in HCC has not yet been systematically explored.

METHODS

To investigate the role of CD146 in HCC, we evaluated its expression in HCC tissues and HCC cell lines using real-time PCR and western blotting (WB). Second, we established HCC cell lines that stably overexpressed and interfered CD146 and explored the function of CD146 in HCC in vitro and in vivo. Third, we conducted microarray analysis to investigate the potential mechanism by identifying differentially expressed genes. Last, follow ups were conducted to help uncover the connection of CD146 expression and the prognosis of HCC patients.

RESULTS

We found that CD146 was overexpressed in HCC tissues and that high CD146 expression predicted poor overall survival time and shorter recurrence period in HCC patients. In vitro and in vivo experiments indicated that CD146 promoted migration and invasion of HCC cell lines. Further study indicated that CD146 promoted epithelial mesenchymal transition (EMT), IL-8 upregulation, and STAT1 downregulation. CD146 was upregulated in HCC tissues and cell lines.

CONCLUSIONS

CD146 promoted metastasis of HCC cells and predicted poor prognosis of HCC patients. CD146 induced EMT, and IL-8 upregulation and STAT1 downregulation may be the potential underlying mechanism. The exact mechanism still needs further investigation.

Stanniocalcin-1 Reduces Tumor Size in Human Hepatocellular Carcinoma

Growing evidence has revealed high expression levels of stanniocalcin-1 (STC1) in different types of human cancers. Numerous experimental studies using cancer cell lines demonstrated the involvement of STC1 in inflammatory and apoptotic processes; however the role of STC1 in carcinogenesis remains elusive. Hepatocellular carcinoma (HCC) an exemplified model of inflammation-related cancer, represents a paradigm of studying the association between STC1 and tumor development. Therefore, we conducted a statistical analysis on the expression levels of STC1 using clinicopathological data from 216 HCC patients. We found that STC1 was upregulated in the tumor tissues and its expression levels was positively correlated with the levels of interleukin (IL)-6 and IL-8. Intriguingly tumors with greater expression levels of STC1 (tumor/normal ≥ 2) were significantly smaller than the lower level (tumor/normal<2) samples (p = 0.008). A pharmacological approach was implemented to reveal the functional correlation between STC1 and the ILs in the HCC cell-lines. IL-6 and IL-8 treatment of Hep3B cells induced STC1 expression. Lentiviral-based STC1 overexpression in Hep3B and MHCC-97L cells however showed inhibitory action on the pro-migratory effects of IL-6 and IL-8 and reduced size of tumor spheroids. The inhibitory effect of STC1 on tumor growth was confirmed in vivo using the stable STC1-overexpressing 97L cells on a mouse xenograft model. Genetic analysis of the xenografts derived from the STC1-overexpressing 97L cells, showed upregulation of the pro-apoptotic genes interleukin-12 and NOD-like receptor family, pyrin domain-containing 3. Collectively, the anti-inflammatory and pro-apoptotic functions of STC1 were suggested to relate its inhibitory effect on the growth of HCC cells. This study supports the notion that STC1 may be a potential therapeutic target for inflammatory tumors in HCC patients.

3D culture broadly regulates tumor cell hypoxia response and angiogenesis via pro-inflammatory pathways

Oxygen status and tissue dimensionality are critical determinants of tumor angiogenesis, a hallmark of cancer and an enduring target for therapeutic intervention. However, it is unclear how these microenvironmental conditions interact to promote neovascularization, due in part to a lack of comprehensive, unbiased data sets describing tumor cell gene expression as a function of oxygen levels within three-dimensional (3D) culture. Here, we utilized alginate-based, oxygen-controlled 3D tumor models to study the interdependence of culture context and the hypoxia response. Microarray gene expression analysis of tumor cells cultured in 2D versus 3D under ambient or hypoxic conditions revealed striking interdependence between culture dimensionality and hypoxia response, which was mediated in part by pro-inflammatory signaling pathways. In particular, interleukin-8 (IL-8) emerged as a major player in the microenvironmental regulation of the hypoxia program. Notably, this interaction between dimensionality and oxygen status via IL-8 increased angiogenic sprouting in a 3D endothelial invasion assay. Taken together, our data suggest that pro-inflammatory pathways are critical regulators of tumor hypoxia response within 3D environments that ultimately impact tumor angiogenesis, potentially providing important therapeutic targets. Furthermore, these results highlight the importance of pathologically relevant tissue culture models to study the complex physical and chemical processes by which the cancer microenvironment mediates new vessel formation.

The role of the cell-cell interactions in cancer progression

In the field of cancer research, scientific investigations are based on analysing differences in the secretome, the proteome, the transcriptome, the expression of cell surface molecules, and the deregulation of signal transduction pathways between neoplastic and normal cells. Accumulating evidence indicates a crucial role in carcinogenesis concerning not only stromal cells but also normal cells from target organs and tissue where tumours emerge. The tumour microenvironment (TME) definitively plays an important role in regulating neighbouring cell behaviour. To date, limited attention has been focused upon interactions between cancer cells and normal cells. This review concentrates on the interactions between stromal and healthy cells from the TME in cancer development. In the article, the authors also describe mutations, genes and proteins expression pattern that are involved in tumour development in target organ.

Interleukin-8 does not influence proliferation of the SGC7901 gastric cancer cell line

Interleukin-8 (IL-8), an important inflammatory factor, is induced by Helicobacter pylori infection and is clearly associated with gastric cancer. IL-8 levels have been revealed to correlate significantly with the adhesion, migration and invasion of gastric cancer cells. However, whether IL-8 influences cell proliferation in gastric cancer remains unclear. In the present study, the effect of IL-8 on the proliferation of the SGC7901 human gastric cancer cell line was investigated. SGC7901 cells were exposed to various concentrations of IL-8 (0, 0.2, 0.5, 0.8 and 1 ng/ml) for one to seven days. Cell proliferation was detected by Cell Counting Kit-8 assay. In addition, proliferating cell nuclear antigen (PCNA) protein and mRNA levels were measured by immunofluorescence, western blotting and quantitative polymerase chain reaction. Following exposure of SGC7901 cells to the various concentrations of IL-8, no significant changes in terms of cell proliferation were identified. However, IL-8 was shown to regulate PCNA protein and mRNA expression levels; at a concentration of 0.8 ng/ml, IL-8 significantly elevated the PCNA protein and mRNA expression levels, whereas IL-8 significantly inhibited these levels at other concentrations, compared with no treatment. In conclusion, IL-8 does not affect the proliferation of SGC7901 cells. However, IL-8 dosage was associated with PCNA protein and mRNA expression levels.

The commonly used antimicrobial additive triclosan is a liver tumor promoter

Triclosan [5-chloro-2-(2,4-dichlorophenoxy)phenol; TCS] is a synthetic, broad-spectrum antibacterial chemical used in a wide range of consumer products including soaps, cosmetics, therapeutics, and plastics. The general population is exposed to TCS because of its prevalence in a variety of daily care products as well as through waterborne contamination. TCS is linked to a multitude of health and environmental effects, ranging from endocrine disruption and impaired muscle contraction to effects on aquatic ecosystems. We discovered that TCS was capable of stimulating liver cell proliferation and fibrotic responses, accompanied by signs of oxidative stress. Through a reporter screening assay with an array of nuclear xenobiotic receptors (XenoRs), we found that TCS activates the nuclear receptor constitutive androstane receptor (CAR) and, contrary to previous reports, has no significant effect on mouse peroxisome proliferation activating receptor α (PPARα). Using the procarcinogen diethylnitrosamine (DEN) to initiate tumorigenesis in mice, we discovered that TCS substantially accelerates hepatocellular carcinoma (HCC) development, acting as a liver tumor promoter. TCS-treated mice exhibited a large increase in tumor multiplicity, size, and incidence compared with control mice. TCS-mediated liver regeneration and fibrosis preceded HCC development and may constitute the primary tumor-promoting mechanism through which TCS acts. These findings strongly suggest there are adverse health effects in mice with long-term TCS exposure, especially on enhancing liver fibrogenesis and tumorigenesis, and the relevance of TCS liver toxicity to humans should be evaluated.

The role of EGF-EGFR signalling pathway in hepatocellular carcinoma inflammatory microenvironment

Epidermal growth factor (EGF) and their receptor (EGFR) play an important role in the development of cancer proliferation, and metastasis, although the mechanism remains unclear. The present study aimed at investigating the role of EGF-EGFR signalling pathway in the development of human hepatocellular carcinoma (HCC) inflammatory environment. Gene profiles of inflammatory cytokines from HCC were measured. Cell bio-behaviours of HCC with low or high metastasis were detected by the live cell monitoring system. Cell proliferation was measured by CCK8. The protein level of CXCL5 and CXCL8 was measured by ELISA. The phosphorylation of PI3K, ERK, MAPK was measured by western blot. EGF significantly induced cell proliferation in HepG2 cells, but not in HCCLM3 cells. EGF prompted the cell movement in both HepG2 and HCCLM3 and regulated the production of CXCL5 and CXCL8 from HCC, which were inhibited by EGFR inhibitor, Erk inhibitor (U0126), or PI3K inhibitors (BEZ-235 and SHBM1009). HCC proliferation, metastasis and production of inflammatory cytokines were regulated via EGF-EGFR signal pathways. CXCL5 could interact with CXCL8, possibly by CXCR2 or the cross-talk between CXCR2 and EGFR. EGF-EGFR signaling pathway can be the potential target of therapies for HCC.

Vascular endothelial cells facilitated HCC invasion and metastasis through the Akt and NF-κB pathways induced by paracrine cytokines

Background

It is well documented that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effects of endothelial cells on the behavior of tumor cells. The study here was to determine the roles of endothelial cells in HCC cell growth, migration and invasion.

Methods

A mixture of highly metastatic MHCC97H cells and HUVEC cells, as well as MHCC97H cells alone were subcutaneously injected into nude mice to observe the effects of HUVECs on HCC growth. The biological characteristics of MHCC97H cells respectively treated with conditioned medium (CM) derived from HUVECs and endothelial cell basal medium (EBM) in vitro, such as proliferation, migration and invasion, invasion/metastasis associated gene expression, were comparatively analyzed. Differential cytokines between CM and EBM were screened and identified using human cytokine array. Effects of the interested differential cytokine CCL2, IL-8 and CXCL16 and its related signaling pathways were further investigated in HCC cells.

Results

Subcutaneous tumorigenicity of MHCC97H cells in nude mice was promoted by HUVECs and its invasion/metastasis associated genes were significantly upregulated. The in vitro, proliferation, migration and invasion of HCC cells treated with CM were all significantly enhanced as compared to those with EBM stimulation. Simultaneously, PI3K/Akt and ERK1/2 pathway in HCC cells were activated by CM. Total of 25 differential cytokines were identified between CM and EBM such as angiopoietin-2, CCL2 (MCP-1), uPA, endostatin, CXCL16, IL-8, pentraxin 3 etc. The selected differential cytokines CCL2, IL-8 and CXCL16 all modulated the expressions of HCC invasion/metastasis genes, especially MMP2 and MMP9. In exposure to CCL2 or CXCL16 alone, upregulation in AKT phosphorylation but no change in ERK phosphorylation were found in MHCC97H cells, moreover the contents of nuclear transcription factor NF-κB were increased as compared to the control. However, no effects on the activation of Akt and ERK pathway in MHCC97H were found in exposure to IL-8.

Conclusion

This study expands the contribution of endothelial cells to the progression of HCC. It unveils a new paradigm in which endothelial cells function as initiators of molecular crosstalks that enhance survival, migration and invasion of HCC cells.

Tumor microenviroment and hepatocellular carcinoma metastasis

The cross talk between tumor cells and the surrounding peritumoral stroma has been extensively studied as a dynamic system involving the processes of hepatocarcinogenesis, tumor invasion, and metastasis in recent few decades. Besides hepatocytes, liver tumor microenvironments are generally classified into cellular and noncellular components, including hepatic stellate cells, fibroblasts, immune, endothelial, mesenchymal stem cells, together with growth factors, cytokines, extracellular matrix, hormone as well as viruses et al. The noncellular components manipulate hepatocellular carcinoma invasion and metastasis by facilitating epithelial-mesenchymal transition, increasing proteolytic activity of matrix metalloproteinases, and regulating antitumor immunity, etc. Because the main cause of death in hepatocellular carcinoma patients is tumor progression with metastasis, a better understanding of the interplay between hepatocytes and their environment during tumor metastasis may be helpful for the discovery of novel molecular targets.

Expression of Brachyury gene is a significant prognostic factor for primary lung carcinoma

BACKGROUND

The clinical significance of Brachyury expression and its relationship to epithelial-mesenchymal transition in primary lung carcinoma is unclear.

METHODS

Expression of Brachyury mRNA was investigated in 104 surgically resected primary lung carcinoma tissues. Immunohistochemical analysis of Brachyury transcription factor, Slug, E-cadherin, IL-8, N-cadherin, and Ki67 was performed in 67 of 104 cases, and their expression was correlated to prognoses and clinicopathological factors.

RESULTS

Brachyury mRNA expression in primary lung carcinoma tissues was a significant predictor of poor prognosis for 5-year disease-free survival and overall survival rates and was significantly correlated to vascular invasion, lymphatic permeation, histological grade, pathologic T stage, and pathologic N stage (P < 0.05). Brachyury mRNA expression was significantly inversely correlated to E-cadherin expression (P = 0.0252) and positively correlated to IL-8 protein (P = 0.0241) and to Slug protein (P = 0.0243) in adenocarcinoma tissues.

CONCLUSIONS

A positive association between Brachyury and Slug and IL-8, and a negative association with E-cadherin may lead to invasiveness and metastasis in primary lung carcinoma. Brachyury mRNA expression is a significant predictor of poor prognosis in primary lung carcinoma.

Evaluation of selenite effects on selenoproteins and cytokinome in human hepatoma cell lines

The need to explore new alternative therapeutic strategies and chemoprevention methods for hepatocellular carcinoma is growing significantly. Selenium is a trace element that plays a critical role in physiological processes, and is used in cancer chemoprevention. The aim of this work was to test in vitro the effect of sodium selenite on the human hepatoma cell lines, HepG2 and Huh7, to assess its effect on the expression of GPX1, SELK and SELENBP1 and also to evaluate its action on inflammation determinants such as cytokines. Our results show that: (i) the increase observed for the GPX1 and SELK expression is correlated with an increase in the sodium selenite concentration, also evidencing an inverse association between the levels of these two proteins and SELENBP1; (ii) the selenium concentrations evaluated in protein extracts increase in proportional way with the selenite concentrations used in the treatment, suggesting that other selenoproteins can also be modulated and should be evaluated in further studies, and (iii) some cytokines, VEGF and three pro-inflammatory cytokines, i.e., IL-6, IL-8, and IL-17, decreased with an increasing selenite concentration. Finally, interactomic studies show that GPX1 and SELK, and the four pro-inflammatory cytokines are functionally correlated evidencing a putative anti-inflammatory role for the selenite.

Molecular Biomarkers of Response to Antiangiogenic Therapy for Cancer

Antiangiogenic therapy for cancer has gone from an intriguing hypothesis in the 1970s to an accepted treatment approach for many cancer types. It has also become a standard of care for certain eye diseases. Yet, despite the use of molecularly targeted drugs with well defined targets, to date there are no biomarkers to guide the use of antiangiogenic therapy in patients. The mechanisms of action of these drugs are also being debated. This paper discusses some of the emerging biomarker candidates for this type of cancer therapy, which have provided mechanistic insight and might be useful in the future for optimizing cancer treatment.

Elevated serum IL-8 is associated with the presence of hepatocellular carcinoma and independently predicts survival

Tumor immune responses have prognostic importance to hepatocellular carcinoma (HCC). Serum cytokines may differentiate HCC patients from cirrhotic patients or have prognostic significance. Serum IL-8 was elevated in 90 HCC patients compared to 180 cirrhotic controls, whereas IL-1β, IL-2, IL-4, IL-6, IL-7, IL-10, IL-12, IL-13, IL-15, IL-17, IL-21, and VEGF were similar. IL-8 predicted HCC presence with an area under the receiver-operator curve (ROC) of 0.68. HCC patients with highest IL-8 had worse survival. Multivariate analysis showed that high IL-8 (HR 2.15; 95%CI:1.21-3.74) and stage (HR 1.92; 95%CI:1.22-3.97) independently predicted mortality; while viral etiology was protective (HR 0.69; 95%CI:0.41-0.98). Therefore, HCC IL-8 mediated events may be worthy of future investigation.

Regulatory mechanisms of interleukin-8 production induced by tumour necrosis factor-α in human hepatocellular carcinoma cells

Interleukin (IL)-8 plays the critical role in the initiation of micro-environmental inflammation responsible for tumour growth and patient prognosis. This study aimed at investigating the molecular mechanisms of IL-8 production from human hepatocellular carcinoma (HCC) cells. The levels of IL-8 and phosphorylation of p38 mitogen-activated protein kinase (MAPK), ERK1/2 and Akt in MHCC-97H cells were measured by ELISA, Western blot and immunofluorescence. NF-κB p65 protein nuclear translocation was determined by non-radioactive NF-κB p50/p65 transcription factor activity kit and cell bio-behaviours were detected by the real-time cell-monitoring system. Tumour necrosis factor-α (TNF-α) significantly induced phosphorylation of p38 MAPK, ERK, Akt and production of IL-8 from HCC cells, which were prevented by SB203580 (p38 MAPK inhibitor), PD98059 (ERK inhibitor), LY294002 and Wortmannin (PI3K inhibitor) and SB328437 (CCR3 inhibitor). TNF-α could significantly increase the translocation of NF-κB p65 protein into the nucleus in a dose-dependent manner, while SB203580 partially inhibited. In inflammatory micro-environment, HCC auto-produced IL-8 through p38 MAPK, ERK and PI3K/Akt signalling pathways, where the p38 MAPK is a central factor to activate the NF-κB pathway and regulate the expression of IL-8 production. There was a potential cross-talking between receptors.

Inflammation and cancer

There is evidence supporting the hypothesis that inflammation participates in providing conditions that lead to cancer. An unresolved inflammation due to any failure in the precise control of the immune response can continue to perturb the cellular microenvironment, thereby leading to alterations in cancer-related genes and posttranslational modification in crucial cellular proteins involved in the cell cycle, DNA repair and apoptosis. In addition, there are data indicating that inflammatory cells and immunomodulatory mediators present in the tumor microenvironment influence tumor progression and metastasis. Historically, tumor-infiltrating leukocytes have been considered to be manifestations of an intrinsic defence mechanism against developing tumors. However, increasing evidence indicates that leukocyte infiltration can promote tumor phenotypes, such as angiogenesis, growth and invasion. This may be due to inflammatory cells that probably can influence cancer promotion by secreting cytokines, growth factors, chemokines and proteases, which stimulate proliferation and invasiveness of cancer cells. Consequently, events and molecules implicated in this cross talk between the tumor microenvironment and inflammatory process may emerge as attractive targets in anticancer therapeutic interventions with significant clinical impact.

Gene expression profiling of HCV genotype 3a initial liver fibrosis and cirrhosis patients using microarray

BACKGROUND

Hepatitis C virus (HCV) causes liver fibrosis that may lead to liver cirrhosis or hepatocellular carcinoma (HCC), and may partially depend on infecting viral genotype. HCV genotype 3a is being more common in Asian population, especially Pakistan; the detail mechanism of infection still needs to be explored. In this study, we investigated and compared the gene expression profile between initial fibrosis stage and cirrhotic 3a genotype patients.

METHODS

Gene expression profiling of human liver tissues was performed containing more than 22000 known genes. Using Oparray protocol, preparation and hybridization of slides was carried out and followed by scanning with GeneTAC integrator 4.0 software. Normalization of the data was obtained using MIDAS software and Significant Microarray Analysis (SAM) was performed to obtain differentially expressed candidate genes.

RESULTS

Out of 22000 genes studied, 219 differentially regulated genes found with P ≤ 0.05 between both groups; 107 among those were up-regulated and 112 were down-regulated. These genes were classified into 31 categories according to their biological functions. The main categories included: apoptosis, immune response, cell signaling, kinase activity, lipid metabolism, protein metabolism, protein modulation, metabolism, vision, cell structure, cytoskeleton, nervous system, protein metabolism, protein modulation, signal transduction, transcriptional regulation and transport activity.

CONCLUSION

This is the first study on gene expression profiling in patients associated with genotype 3a using microarray analysis. These findings represent a broad portrait of genomic changes in early HCV associated fibrosis and cirrhosis. We hope that identified genes in this study will help in future to act as prognostic and diagnostic markers to differentiate fibrotic patients from cirrhotic ones.

CD133(+) liver tumor-initiating cells promote tumor angiogenesis, growth, and self-renewal through neurotensin/interleukin-8/CXCL1 signaling

A novel theory in the field of tumor biology postulates that cancer growth is driven by a population of stem-like cells, called tumor-initiating cells (TICs). We previously identified a TIC population derived from hepatocellular carcinoma (HCC) that is characterized by membrane expression of CD133. Here, we describe a novel mechanism by which these cells mediate tumor growth and angiogenesis by systematic comparison of the gene expression profiles between sorted CD133 liver subpopulations through genome-wide microarray analysis. A significantly dysregulated interleukin-8 (IL-8) signaling network was identified in CD133(+) liver TICs obtained from HCC clinical samples and cell lines. IL-8 was found to be overexpressed at both the genomic and proteomic levels in CD133(+) cells isolated from HCC cell lines or clinical samples. Functional studies found enhanced IL-8 secretion in CD133(+) liver TICs to exhibit a greater ability to self-renew, induce tumor angiogenesis, and initiate tumors. In further support of these observations, IL-8 repression in CD133(+) liver TICs by knockdown or neutralizing antibody abolished these effects. Subsequent studies of the IL-8 functional network identified neurotensin (NTS) and CXCL1 to be preferentially expressed in CD133(+) liver TICs. Addition of exogenous NTS resulted in concomitant up-regulation of IL-8 and CXCL1 with simultaneous activation of p-ERK1/2 and RAF-1, both key components of the mitogen-activated protein kinase (MAPK) pathway. Enhanced IL-8 secretion by CD133(+) liver TICs can in turn activate an IL-8-dependent feedback loop that signals through the MAPK pathway. Further, in its role as a liver TIC marker CD133 also plays a functional part in regulating tumorigenesis of liver TICs by way of regulating NTS, IL-8, CXCL1, and MAPK signaling.

CONCLUSION

CD133(+) liver TICs promote angiogenesis, tumorigenesis, and self-renewal through NTS-induced activation of the IL-8 signaling cascade.

The IL-8 gene polymorphisms and the risk of the hepatitis B virus/infected patients

Interleukin-8 (IL-8) belongs to the superfamily of CXC chemokines, contributing to human cancer progression through potential mitogenic, angiogenic, and motogenic functions. We hypothesize that the functional polymorphism of IL-8 may influence the inflammatory process during pathological stage from hepatitis to hepatocellular carcinoma (HCC). Two polymorphisms in the IL-8 gene (-251A/T and +781C/T) were examined in 160 cases of chronic hepatitis B, 80 cases of hepatitis B virus (HBV)-related liver cirrhosis (LC), 150 cases of HBV-related HCC, and 150 healthy controls using polymerase chain reaction-restriction fragment length polymorphism method and DNA sequencing. In the LC group, the AA genotypes were associated with a significantly decreased risk of LC compared with the TT genotype (OR=0.14, 95% CI 0.02-0.87, p=0.035). The data also revealed that subjects with the A allele appeared to have lower susceptibility to LC than those with the T allele (OR=0.48, 95% CI 0.25-0.92, p=0.027). The +781C/T polymorphism of IL-8 was not found relevant to the liver diseases. This study indicated that the IL-8 gene -251 AA genotype might be a protect factor for LC.

Efficacy, safety, and potential biomarkers of thalidomide plus metronomic chemotherapy for advanced hepatocellular carcinoma

OBJECTIVES

Thalidomide has been shown to have antitumor activity in some patients with advanced hepatocellular carcinoma (HCC). We initiated a phase II study to determine the safety and efficacy of adding metronomic chemotherapy to thalidomide as first-line therapy.

METHODS

This open- labeled, single-arm, multicentered, investigator-initiated study enrolled patients with treatment-naïve advanced HCC not amenable to locoregional therapies. Treatment included oral thalidomide (100 mg twice daily) and tegafur/uracil [125 mg/m(2) (based on tegafur) twice daily]. Tumor assessment was performed according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.0. Pretreatment plasma levels of angiogenesis factors were correlated with patient outcomes.

RESULTS

Forty-three patients were included. Sixteen (37%) patients had a Cancer of the Liver Italian Program (CLIP) score of 4, and 31 (72%) patients had chronic hepatitis B virus infection. The objective response rate was 9%, and the disease stabilization rate was 33%. The median progression-free survival was 1.9 months (95% CI 1.7-2.1 months), and the median OS was 4.6 months (95% CI 2.3-6.9 months). Treatment was generally tolerable. High baseline plasma levels of interleukin (IL)-6 and IL-8 were adversely correlated with patient survivals.

CONCLUSIONS

The combination of thalidomide and tegafur/uracil was safe and demonstrated modest activity in patients with advanced HCC.

Effects of lipoic acid, caffeic acid and a synthesized lipoyl-caffeic conjugate on human hepatoma cell lines

Hepatocellular carcinoma (HCC) is among the most aggressive and fatal cancers. Its treatment with conventional chemotherapeutic agents is inefficient, due to several side effects linked to impaired organ function typical of liver diseases. Consequently, there exists a decisive requirement to explore possible alternative chemopreventive and therapeutic strategies. The use of dietary antioxidants and micronutrients has been proposed for HCC successful management. The aim of this work was to test in vitro the effects of lipoic acid, caffeic acid and a new synthesized lipoyl-caffeic conjugate on human hepatoma cell lines in order to assess their effect on tumor cell growth. The results of cytotoxicity assays at different times showed that the cell viability was directly proportional to the molecule concentrations and incubation times. Moreover, to evaluate the pro- or anti-inflammatory effects of these molecules, the cytokine concentrations were evaluated in treated and untreated cellular supernatants. The obtained cytokine pattern showed that, at the increasing of three molecules concentrations, three pro-inflammatory cytokines such as IL-1β, IL-8 and TNF-α decreased whereas the anti-inflammatory cytokine such as IL-10 increased.

Association of specific genotypes in metastatic suppressor HTPAP with tumor metastasis and clinical prognosis in hepatocellular carcinoma

The phosphatidic acid phosphatase HTPAP has been defined as a metastatic suppressor of hepatocellular carcinoma (HCC), but little is known about its function or potential applications as a prognostic marker. In this study, we analyzed patterns of HTPAP genetic variation and gene expression in 864 patients who underwent HCC resection, assessing these patterns for correlations to tumor metastasis potential. Focusing on two tagSNPs that were selected (+357G/C and +1838A/G), we found that only the +357G/C genotype was significantly associated with HTPAP mRNA and protein expression levels and the probability of metastasis. In an independent cohort of 665 HCC patients, we determined that the +357G/C genotype was associated with shorter time to recurrence and overall survival. Together, these results indicated that the HTPAP tagSNP +357 GG+GC genotypes may influence HCC metastatic potential and clinical prognosis by down-regulating HTPAP expression. Extending these results, a global expression profiling analysis identified 41 genes including the pro-inflammatory genes IL-8 and TLR2 that were significantly overexpressed in the +357 GG+GC group, as possible coregulated markers with HTPAP. Together, our findings identify an HTPAP genotype and associated gene expression pattern that favors metastasis progression and that could be used to predict tumor metastasis and prognosis in HCC patients.

HCC and angiogenesis: possible targets and future directions

Hepatocellular carcinoma (HCC), the most common primary liver tumor, is notoriously resistant to systemic therapies, and often recurs even after aggressive local therapies. HCCs rely on the formation of new blood vessels for growth, and VEGF is critical in this process. A hallmark of new vessel formation in tumors is their structural and functional abnormality. This leads to an abnormal tumor microenvironment characterized by low oxygen tension. The liver is perfused by both arterial and venous blood and the resulting abnormal microenvironment selects for more-aggressive malignancies. Anti-VEGF therapy with sorafenib was the first systemic therapy to demonstrate improved survival in patients with advanced-stage HCC. This important development in the treatment of HCC raises hope as well as critical questions on the future development of targeted agents including other antiangiogenic agents, which hold promise to further increase survival in this aggressive disease.

Down-regulation of methylthioadenosine phosphorylase (MTAP) induces progression of hepatocellular carcinoma via accumulation of 5'-deoxy-5'-methylthioadenosine (MTA)

Recently, we have shown that down-regulation of methylthioadenosine phosphorylase (MTAP) in hepatocellular carcinoma (HCC) cells enhances the invasive potential and the resistance against cytokines. Here, we aimed at investigating the molecular mechanism underlying this tumor-promoting effect and expanded the analysis to a large series of human HCC tissues. Liquid chromatography tandem mass spectrometry revealed that reduced MTAP expression resulted in higher intra- and extracellular concentrations of 5'-deoxy-5'-methylthioadenosine (MTA) in cultivated HCC cells and, concordantly, higher levels of MTA in HCC tissue. MTA induced matrix metalloproteinase (MMP) and interleukin-8 transcription in HCC cells in vitro, accompanied by enhanced proliferation and activation of the transcription factor NFκB. In addition, MTA secreted by HCC cells induced expression of fibroblast growth factor-2 and MMP1 in stromal myofibroblasts. In human HCC tissues, MTAP mRNA correlated inversely with MTA levels, and immunohistochemical analysis of a tissue microarray of 140 human HCCs revealed that low MTAP protein expression correlated with advanced tumor stages. In conclusion, MTAP deficiency results in accumulation of MTA, which is associated with increased tumorigenicity. These data further indicate MTAP as a tumor suppressor in HCC, and MTA as a potential biomarker for HCC progression.

Antiangiogenic potential of three triterpenic acids in human liver cancer cells

Three triterpenic acids, oleanolic acid, ursolic acid and maslinic acid, at 2 or 4 μmol/L were used to study their antiangiogenic potential in human liver cancer Hep3B, Huh7 and HA22T cell lines. The effects of these compounds upon the level and/or expression of hypoxia-inducible factor (HIF)-1α, basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), interleukin (IL)-8, urokinase plasminogen activator (uPA), reactive oxygen species (ROS), nitric oxide (NO) and cell invasion and migration were examined. Results showed that these triterpenic acids at 4 μmol/L significantly suppressed HIF-1α expression in three cell lines (P < 0.05); and these compounds at test doses failed to affect bFGF expression (P > 0.05). Three triterpenic acids dose-dependently decreased production and expression of VEGF and IL-8, retained glutathione level, lowered ROS and NO levels, and declined cell invasion and migration in test cell lines (P < 0.05). These compounds also dose-dependently reduced uPA production and expression in Hep3B and Huh7 cell lines (P < 0.05); but these agents only at 4 μmol/L significantly suppressed uPA production and expression in HA22T cells (P < 0.05). These findings suggest that these triterpenic acids are potent antiangiogenic agents to retard invasion and migration in liver cancer cells.

Interleukin-8 is associated with adhesion, migration and invasion in human gastric cancer SCG-7901 cells

Interleukin-8 is known as an important chemokine involved in tumor angiogenesis and progression. Overexpression of interleukin-8 has been detected in a variety of human tumors, including gastric cancer, and is negatively correlated with prognosis. The aim of our study is to determine the effects of interleukin-8 on proliferation, adhesion, migration and invasion abilities and correlated molecular mechanisms in gastric cancer. We made recombinant interleukin-8 ranged from 0 ng/ml to 100 ng/ml interferes in human gastric cancer SCG-7901 cells in vitro. The results shown that interleukin-8 did not change cell proliferation, but promoted cell adhesion to endothelial cell and extracellular matrix components (collagen, laminin and fibronectin) as detected by Cell Counting Kit-8. And it induced migration and invasion ability based on scratch and transwell-chamber assays. Also, interleukin-8 regulated the protein and mRNA expression of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad and there was obviously a dose-dependent relationship, but the protein or mRNA expression of matrix metalloproteinase-2 was not obviously changed under the tested conditions. Our findings indicate that interleukin-8 is associated with adhesion, migration and invasion in gastric cancer and the regulation of matrix metalloproteinase-9, intercellular adhesion molecule-1 and E-cad expression is one of the potential molecule mechanisms. The studies imply interleukin-8 may be an alternative treatment strategy against gastric cancer.

IL-8 is a mediator of NF-κB induced invasion by gliomas

Glioblastoma (GBM) is the most common and deadly form of primary brain tumor with a median survival of eleven months, despite use of extensive chemotherapy, radiotherapy and surgery. We have previously shown that nuclear factor-kappa B (NF-κB) is aberrantly expressed in GBM tumors and primary cell lines derived from tumor tissue. Here we show that IL-8, a chemokine is also aberrantly expressed by GBM cell lines and expression of IL-8 is in large part, attributable to the aberrant activation of NF-κB. We hypothesized that invasiveness of GBM cells is driven at least in part by aberrantly expressed IL-8. In support of the hypothesis we found that treatment of glioma cells with an IL-8 neutralizing antibody markedly decreased their invasiveness compared to cells treated with control IgG or left untreated. Furthermore, downregulation of IL-8 protein production with use of IL-8 targeted siRNA also resulted in decreased invasion in matrigel. We next investigated the presence of IL-8 receptors by FACS analysis and found that GBM cells (U87, U251, D54 and LN229) only express CXCR1 but not CXCR2. Treatment of U87 cells with a blocking CXCR1 antibody reduced their invasion through matrigel. Finally, we found that addition of exogenous IL-8, following downregulation of NF-κB which results in loss of endogenous IL-8 production, incompletely restored tumor cell invasion. Our data indicate that IL-8 is necessary but not solely responsible for glioma cell invasion and mediates its effect in an autocrine manner.

Chemokine CCL3 facilitates the migration of hepatoma cells by changing the concentration intracellular Ca

AIM

Recurrence and metastasis are the major factors associated with the poor prognosis of hepatocellular carcinoma (HCC). It was confirmed that multiple chemokines and their receptors are related to the progression and metastasis of HCC. The aim of this research was to conduct an investigation into whether macrophage inflammatory protein-1alpha/CCL3, and its receptor CCR1 play a role in HCC invasion and metastasis.

METHODS

We used reverse transcription polymerase chain reaction, immunocytochemistry and flow cytometry to detect CCR1 mRNA and protein expression in the four hepatoma cell lines HepG2, Hep3B, HLE and HLF; and we conducted a microscope cell migration experiment to observe the pseudopodia formation and mobility of the hepatoma cells. The concentration of intracellular calcium was measured by fluorescence microscopy.

RESULTS

CCR1 mRNA and protein were positively expressed in the four hepatoma cell lines HepG2, Hep3B, HLE and HLF. Following CCL3 stimulation, obvious pseudopodia formation of hepatoma cells was observed using a fluorescence microscope. The cell migration experiment showed that after incubation with CCL3, the number of Hep3B cells which passed through the polycarbonate microporous filter membranes increased to an obvious extent. After CCL3 incubation, the intracellular Ca(2+) level of the Hep3B cells increased to an obvious extent.

CONCLUSION

Chemokine CCL3 facilitates the migration of hepatoma by changing the concentration intracellular Ca(2+). The CCL3-CCR1 axis may play an important role in HCC invasion and metastasis. It may also be a potential target for HCC therapy or for prevention of the recurrence and metastasis of HCC.

Serum levels of soluble Fas, soluble tumor necrosis factor-receptor II, interleukin-2 receptor and interleukin-8 as early predictors of hepatocellular carcinoma in Egyptian patients with hepatitis C virus genotype-4

BACKGROUND

Liver disease progression from chronic hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) is associated with an imbalance between T-helper 1 and T-helper 2 cytokines. Evaluation of cytokines as possible candidate biomarkers for prediction of HCC was performed using soluble Fas(sFas), soluble tumor necrosis factor receptor-II (sTNFR-II), interleukin-2 receptor (IL-2R) and interleukin-8 (IL-8).

RESULTS

The following patients were recruited: 79 with HCV infection, 30 with HCC, 32 with chronic liver disease associated with elevated liver enzyme levels (with or without cirrhosis) in addition to 17 with chronic HCV with persistent normal alanine aminotransferase levels (PNALT). Nine normal persons negative either for HCV or for hepatitis B virus were included as a control group. All persons were tested for sFas, sTNFR-II, IL-2R and IL-8 in their serum by quantitative ELISA. HCC patients had higher levels of liver enzymes but lower log-HCV titer when compared to the other groups. HCC patients had also significantly higher levels of sFas, sTNFR-II and IL-2R and significantly lower levels of IL-8 when compared to the other groups. Exclusion of HCC among patients having PNALT could be predicted with 90 % sensitivity and 70.6 % specificity when sTNFR-II is [greater than or equal to] 389 pg/ml or IL-8 is < 290 pg/ml.

CONCLUSIONS

Serum TNFR-II, IL-2Ralpha and IL-8, may be used as combined markers in HCV-infected cases for patients at high risk of developing HCC; further studies, however, are mandatory to check these findings before their application at the population level.

Interleukin-8 producing hepatocellular carcinoma with pyrexia

We discuss a patient who had poorly differentiated HCC with pyrexia and high CRP in laboratory data, which are not commonly observed in the usual HCC. A 50-year-old man with a history of liver dysfunction was admitted with a chief complaint of a prolonged fever and general fatigue. Preoperative diagnosis was HCC with portal vein tumor thrombus. Posterior segmentectomy of the liver and thrombectomy was performed. Rapid tumor recurrence occurred after surgery, and he died 79 days after the operation. Immunohistochemical stain of HCC in this patient revealed the production of proinflammatory cytokine, interleukin-8 (IL-8). IL-8 production may have contributed to the high fever, high inflammatory reaction, and poor prognosis in this case.

Inflammation and cancer: how friendly is the relationship for cancer patients?

Evidence has emerged in the last two decades that at the molecular level most chronic diseases, including cancer, are caused by a dysregulated inflammatory response. The identification of transcription factors such as NF-kappaB, AP-1 and STAT3 and their gene products such as tumor necrosis factor, interleukin-1, interleukin-6, chemokines, cyclooxygenase-2, 5 lipooxygenase, matrix metalloproteases, and vascular endothelial growth factor, adhesion molecules and others have provided the molecular basis for the role of inflammation in cancer. These inflammatory pathways are activated by tobacco, stress, dietary agents, obesity, alcohol, infectious agents, irradiation, and environmental stimuli, which together account for as much as 95% of all cancers. These pathways have been implicated in transformation, survival, proliferation, invasion, angiogenesis, metastasis, chemoresistance, and radioresistance of cancer, so much so that survival and proliferation of most types of cancer stem cells themselves appear to be dependent on the activation of these inflammatory pathways. Most of this evidence, however, is from preclinical studies. Whether these pathways have any role in prevention, progression, diagnosis, prognosis, recurrence or treatment of cancer in patients, is the topic of discussion of this review. We present evidence that inhibitors of inflammatory biomarkers may have a role in both prevention and treatment of cancer.

Activated hepatic stellate cells promote tumorigenicity of hepatocellular carcinoma

Liver cirrhosis is the main risk factor for the development of hepatocellular carcinoma (HCC). Activated hepatic stellate cells (HSC) are the effector cells of hepatic fibrosis and also infiltrate the HCC stroma where they might play a critical role in HCC progression. Here we aimed to analyze the effects of activated HSC on the proliferation and growth of HCC cell lines in vitro and in vivo. Conditioned media (CM) collected from HSC significantly induced proliferation and migration of HCC cells cultured in monolayers. In a 3-dimensional spheroid coculture system, HSC promoted HCC growth and diminished the extent of central necrosis. In accordance, in vivo simultaneous implantation of HSC and HCC cells into nude mice promoted tumor growth and invasiveness, and inhibited necrosis formation. As potential mechanism of the tumorigenic effects of HSC we identified activation of NFkappaB and extracellular-regulated kinase (ERK) in HCC cells, two signaling cascades that play a crucial role in HCC progression. In summary, our data indicate that stromal HSC promotes HCC progression and suggest the HSC-HCC interaction as an interesting tumor differentiation-independent target for therapy of this highly aggressive cancer.

Characterization of interleukin 8 in woodchucks with chronic hepatitis B and hepatocellular carcinoma

The eastern woodchuck, Marmota monax, represents a useful animal model to study hepatitis B virus infection in humans. However, immunological studies in this model have been impeded by a lack of basic information about the components of the immune system such as cytokines and chemokines. To clarify the role(s) of interleukin 8 (IL-8) in chronic hepatitis B and hepatocellular carcinoma (HCC) in the woodchuck model, we cloned and characterized the woodchuck IL-8 cDNA and genomic DNA. Sequence analysis revealed that the organization of the wk-IL-8 gene is similar to that of the human IL-8 gene and consists of four exons and three introns. Woodchuck IL-8 protein exhibits the conserved ELRCXC motif of IL-8 and shows 87, 82, 82 and 79% similarity with rabbit, ovine, bovine and human IL-8 proteins, respectively. The biological activity of wk-IL-8 was demonstrated using neutrophil chemotaxis assays. Wk-IL-8 could be readily detected in both tumor and non-tumor tissues with higher expression in the non-tumor tissues in most cases. The results from this study will facilitate the investigation of IL-8 in the immunopathogenesis of hepadnavirus-related diseases by the woodchuck model.

Genetic profile of Egyptian hepatocellular-carcinoma associated with hepatitis C virus Genotype 4 by 15 K cDNA microarray: preliminary study

Background

Hepatocellular carcinoma (HCC) is a preventable disease rather than a curable one, since there is no well-documented effective treatment modality until now, making the molecular study of this disease mandatory.

Findings

We studied gene expression profile of 17 Egyptian HCC patients associated with HCV genotype-4 infection by c-DNA microarray. Out of the 15,660 studied genes, 446 were differentially expressed; 180 of them were up regulated and 134 were down regulated. Seventeen genes out of the 180 up-regulated genes are involved in 28 different pathways. Protein phosphatase 3 (PPP3R1) is involved in 10 different pathways followed by fibroblast growth factor receptor 1 (FGFR1), Cas-Br-M ecotropic retroviral transforming sequence b (CBLB), spleen tyrosine kinase (SYK) involved in three pathways; bone morphogenetic protein 8a (BMP8A), laminin alpha 3 (LAMA3), cell division cycle 23 (CDC23) involved in 2 pathways and NOTCH4 which regulate Notch signaling pathway. On the other hand, 25 out of the 134 down-regulated genes are involved in 20 different pathways. Integrin alpha V alpha polypeptide antigen CD51 (ITGVA) is involved in 4 pathways followed by lymphotoxin alpha (TNF superfamily, member 1) (LTA) involved in 3 pathways and alpha-2-macroglobulin (A2M), phosphorylase kinase alpha 2-liver (PHKA2) and MAGI1 membrane associated guanylate kinase 1 (MAGI1) involved in 2 pathways. In addition, 22 genes showed significantly differential expression between HCC cases with cirrhosis and without cirrhosis. Confirmation analysis was performed on subsets of these genes by RT-PCR, including some up-regulated genes such as CDK4, Bax, NOTCH4 and some down-regulated genes such as ISGF3G, TNF, and VISA.

Conclusion

This is the first preliminary study on gene expression profile in Egyptian HCC patients associated with HCV-Genotype-4 using the cDNA microarray. The identified genes could provide a new gate for prognostic and diagnostic markers for HCC associated with HCV. They could also be used to identify candidate genes for molecular target therapy.

Vascular changes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most vascular solid tumors, in which angiogenesis plays an important role. The status of angiogenesis in HCC correlates with the disease progression and prognosis, and thus provides a potential therapeutic target. This review summarizes the vascular changes and molecular and cellular basis of angiogenesis in HCC. Development of HCC is characterized by arterialization of its blood supply and sinusoidal capillarization. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that plays a critical role in mediating angiogenesis in HCC. The VEGF can function on various types of cells, such as endothelial cells, hepatic stellate cells, endothelial progenitor cells and hemangiocytes, to induce vascular changes in HCC. Therefore, blockade of VEGF-mediated pathways, either by anti-VEGF neutralizing antibody or tyrosine kinase inhibitors that target VEGF receptors, suppresses carcinogenesis and angiogenesis in HCC. In addition to VEGF, several other angiogenic factors in HCC have recently been identified. These factors can also regulate angiogenic processes through interaction with VEGF or VEGF-independent pathways. Despite the fact that treatment of HCC remains a tough task due to lack of effective systemic therapy, antiangiogenic therapy has already entered clinical trials in HCC patients and sheds light on a promising novel treatment for this disease.