CFIm25 inhibits hepatocellular carcinoma metastasis by suppressing the p38 and JNK/c-Jun signaling pathways

Alternative polyadenylation (APA), a post-transcriptional modification, has been implicated in many diseases, but especially in tumor proliferation. CFIm25, the 25 kDa subunit of human cleavage factor Im (CFIm), is a key factor in APA. We show that CFIm25 expression is reduced in human hepatocellular carcinoma (HCC), and its expression correlates with metastasis. Kaplan-Meier analysis indicated that CFIm25 is related to overall survival in HCC. Moreover, CFIm25 expression is negatively related to the metastatic potential of HCC cell lines. CFIm25 knockdown promotes cell invasion and migration in vitro, while overexpression of CFIm25 inhibits cell invasion and migration in vitro and inhibits intrahepatic and lung metastasis in vivo. Additional studies showed that CFIm25 disrupts epithelial-mesenchymal transition by increasing E-cadherin, that it inhibits HCC cell migration and invasion by blocking the p38 and JNK/c-Jun signaling pathways, and that CFIm25 knockdown increases the transcriptional activity of activating protein-1 (AP-1). These findings indicate that therapy directed at increasing CFIm25 expression is a potential HCC treatment.

Vitamin A maintains the airway epithelium in a murine model of asthma by suppressing glucocorticoid-induced leucine zipper

BACKGROUND

The effects of glucocorticoids (GCs) on the repair of the airway epithelium in asthma are controversial, and we previously reported that the GC dexamethasone (Dex) inhibits the repair of human airway epithelial cells and that this process is mediated by glucocorticoid-induced leucine zipper (GILZ) through MAPK-ERK signaling in vitro. Vitamin A (VA) is involved in the regulation of the MAPK-ERK pathway but has not been widely supplied during asthma treatment. It is unclear whether VA attenuates the negative regulation of GILZ on the MAPK-ERK pathway and maintains airway epithelium integrity during asthma treatment.

METHODS

Female BALB/c mice were sensitized and challenged with ovalbumin (OVA) and subsequently treated with Dex, VA or intranasal inhalation of adenovirus sh-GILZ vectors. Indexes of airway epithelium integrity, including pathological alterations, pulmonary EGFR expression and airway hyperresponsiveness (AHR), were then measured. The expression of GILZ and key components of activated MAPK-ERK signals (p-Raf-1, p-MEK, and p-Erk1/2) were also detected.

RESULTS

Dex failed to relieve OVA-induced asthma airway epithelium injury, as assessed through H&E staining, EGFR expression and AHR. Moreover, in the OVA-challenged mice treated with Dex, GLIZ expression was increased, whereas the ratios of p-Raf-1/Raf-1, p-MEK/MEK and p-Erk1/2/Erk1/2 were significantly decreased. Further study indicated that GILZ expression was decreased and that the ratios of p-Raf-1/Raf-1, p-MEK/MEK and p-Erk1/2/Erk1/2 were up-regulated in the GILZ-silenced OVA-challenged mice and VA-fed OVA-challenged mice, independent of Dex treatment. The airway epithelium integrity of the OVA-challenged mice was maintained by treatment with both VA and Dex.

CONCLUSIONS

Vitamin A maintained the Dex-treated asthma airway epithelium via the down-regulation of GILZ expression and the activation MAPK-ERK signaling, and these effects might contribute to improving the effects of GC therapeutics on asthma.

Tumor necrosis factor-α acts reciprocally with solute carrier family 26, member 3, (downregulated-in-adenoma) and reduces its expression, leading to intestinal inflammation

Solute carrier family 26, member 3 (Slc26a3), also termed downregulated-in-adenoma (DRA) is a member of the Slc26 family of anion transporters and is mutated in congenital chloride diarrhea. Our previous study demonstrated that DRA deficiency is associated with severely reduced colonic HCO3‑ secretion, a loss of colonic fluid absorption, a lack of a firmly adherent mucus layer and a severely reduced colonic mucosal resistance to dextran sodium sulfate (DSS) damage. However, the direct effect of mediators that trigger intestinal inflammatory factors on DRA has not been fully investigated. Tumor necrosis factor (TNF)‑α is a central mediator of intestinal inflammation in inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease. However, to the best of our knowledge, whether TNF‑α acts reciprocally with DRA leading to the development of gut inflammation in IBD has not been reported. The present study identified that the expression level of DRA was reduced in active UC patients and DSS‑induced colitis mice with high expression levels of TNF‑α identified in the peripheral blood serum. In addition, TNF‑α may affect the expression level of DRA in human colonic Caco2BBE cells in a dose‑dependent manner, including in DRA overexpressed Caco2BBE cells. Furthermore, knockdown of TNF‑α in Caco2BBE cells led to a higher expression level of DRA and a markedly reduced secretion of TNF‑α in the culture media. In addition, knockdown of DRA in Caco2BBE cells led to a higher secretion of TNF‑α in the culture media compared with the control cells, which could be reversed by overexpression of DRA. Overall, these results indicate that TNF‑α may act reciprocally with DRA, leading to the development of intestinal inflammation. Based on the pivotal position of TNF‑α in IBD, DRA is hypothesized to have therapeutic potential against colitis serving as an important target.

Reconciling agriculture, carbon and biodiversity in a savannah transformation frontier

Rapidly rising populations and likely increases in incomes in sub-Saharan Africa make tens of millions of hectares of cropland expansion nearly inevitable, even with large increases in crop yields. Much of that expansion is likely to occur in higher rainfall savannas, with substantial costs to biodiversity and carbon storage. Zambia presents an acute example of this challenge, with an expected tripling of population by 2050, good potential to expand maize and soya bean production, and large areas of relatively undisturbed miombo woodland and associated habitat types of high biodiversity value. Here, we present a new model designed to explore the potential for targeting agricultural expansion in ways that achieve quantitatively optimal trade-offs between competing economic and environmental objectives: total converted land area (the reciprocal of potential yield); carbon loss, biodiversity loss and transportation costs. To allow different interests to find potential compromises, users can apply varying weights to examine the effects of their subjective preferences on the spatial allocation of new cropland and its costs. We find that small compromises from the objective to convert the highest yielding areas permit large savings in transportation costs, and the carbon and biodiversity impacts resulting from savannah conversion. For example, transferring just 30% of weight from a yield-maximizing objective equally between carbon and biodiversity protection objectives would increase total cropland area by just 2.7%, but result in avoided costs of 27-47% for carbon, biodiversity and transportation. Compromise solutions tend to focus agricultural expansion along existing transportation corridors and in already disturbed areas. Used appropriately, this type of model could help countries find agricultural expansion alternatives and related infrastructure and land use policies that help achieve production targets while helping to conserve Africa's rapidly transforming savannahs.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'.

Transmembrane channel-like protein 8 as a potential biomarker for poor prognosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is an aggressive malignant tumor and the third leading cause of cancer-related mortality worldwide. Transmembrane channel-like protein 8 (TMC8) is reported to play a major role in several aspects of human pathophysiology, such as ion channel permeability, human papillomavirus infection and skin cancer; however, its role in HCC has not been fully elucidated. The aim of the present study was to investigate the expression levels of TMC8 in 146 pairs of liver cancer samples and adjacent non-tumorous samples using immunohistochemistry. Reverse transcription-quantitative polymerase chain reaction analysis was used to confirm the results. The association between TMC8 expression and clinicopathological characteristics, including overall survival, was analyzed. The results indicated that the expression of TMC8 was significantly upregulated in HCC tissues and associated with metastasis and hepatitis B virus infection. According to the analysis of the overall survival using Cox proportional hazard regression model, higher expression of TMC8 was associated with a poorer prognosis and the overexpression of TMC8 was an independent risk factor for HCC. By contrast, HBsAg did not significantly affect the survival of HCC patients. These results suggest that the overexpression of TMC8 in HCC predicts poor prognosis and may be a potential biomarker for this type of cancer.

Knockdown of histidine-rich calcium-binding protein (HRC) suppresses liver fibrosis by inhibiting the activation of hepatic stellate cells

The histidine-rich calcium-binding protein (HRC) is a regulator of Ca²⁺ homeostasis and it plays a significant role in hepatocellular carcinoma (HCC) progression. However, the relationship between HRC and liver fibrogenesis is still unknown. Our data demonstrates that HRC was upregulated in fibrotic liver and activated hepatic stellate cells (HSCs). TGF-β treatment increased α-SMA and HRC expression dose-dependently in HSCs. Repression of HRC reduced α-SMA, CTGF and collagen expression, and inhibited HSC proliferation and migration. In addition, we found that the anti-fibrosis effect of HRC knockdown was associated with endoplasmic reticulum (ER) stress. Silencing of HRC decreased the expression of ER stress and autophagy markers. Moreover, ER stress agonist thapsigargin (TG) enhanced, whereas ER stress antagonist 4-phenylbutyric acid (4-PBA) alleviated HSCs activation and autophagy. In conclusion, these data indicate that depletion of HRC inhibited HSC activation through the ER stress pathway, and HRC may be a potential regulator of liver fibrosis.

[Determination of relative elements of hard metal in workplace air and urine by inductive coupled plama]

Objective: To establish a rapid detection method regarding the air conditions of workplace and the workers' urine included Tungsten, Cobalt, Nickel, Titanium, Cadmium, Manganese, Lead and its compounds based on inductively coupled plasma mass spectrometry (ICP-MS) . Methods: The experiment adopts ICP-MS to deter-mine those metals in workshop air and workers urine, evaluate the detection's limitation, the precision and accuracy of the method. Using the membrane filter and urine freeze - dried metal standard material to verify this method. Results: Each element of correlation coefficient was greater than 0.999. The recovery rate of air samples was 91.6%~104.6%, within-batch RSD precision was 1.41%~3.50%, between-run precision was 1.28%~4.31%, urine samples recovery rate was 93.0%~102.6%, within - batch RSD precision was 1.25%~3.56%, between - run precision was 1.58%~4.67%, According to the method every element was within the scope of the standard reference, it was also showed that the established method is accurate and reliable. Conclusion: ICP-MS is an effective and feasible method to detect the workshop air and the workers' urine which included Tungsten, Cobalt, Nickel, Titanium, Cadmium, Manganese, Lead and its compounds.

A porcine reproductive and respiratory syndrome virus candidate vaccine based on the synthetic attenuated virus engineering approach is attenuated and effective in protecting against homologous virus challenge

Current porcine reproductive and respiratory syndrome virus (PRRSV) vaccines sometimes fail to provide adequate immunity to protect pigs from PRRSV-induced disease. This may be due to antigenic differences among PRRSV strains. Rapid production of attenuated farm-specific homologous vaccines is a feasible alternative to commercial vaccines. In this study, attenuation and efficacy of a codon-pair de-optimized candidate vaccine generated by synthetic attenuated virus engineering approach (SAVE5) were tested in a conventional growing pig model. Forty pigs were vaccinated intranasally or intramuscularly with SAVE5 at day 0 (D0). The remaining 28 pigs were sham-vaccinated with saline. At D42, 30 vaccinated and 19 sham-vaccinated pigs were challenged with the homologous PRRSV strain VR2385. The experiment was terminated at D54. The SAVE5 virus was effectively attenuated as evidenced by a low magnitude of SAVE5 viremia for 1-5 consecutive weeks in 35.9% (14/39) of the vaccinated pigs, lack of detectable nasal SAVE5 shedding and failure to transmit the vaccine virus from pig to pig. By D42, all vaccinated pigs with detectable SAVE5 viremia also had detectable anti-PRRSV IgG. Anti-IgG positive vaccinated pigs were protected from subsequent VR2385 challenge as evidenced by lack of VR2385 viremia and nasal shedding, significantly reduced macroscopic and microscopic lung lesions and significantly reduced amount of PRRSV antigen in lungs compared to the non-vaccinated VR2385-challenged positive control pigs. The nasal vaccination route appeared to be more effective in inducing protective immunity in a larger number of pigs compared to the intramuscular route. Vaccinated pigs without detectable SAVE5 viremia did not seroconvert and were fully susceptible to VR2385 challenge. Under the study conditions, the SAVE approach was successful in attenuating PRRSV strain VR2385 and protected against homologous virus challenge. Virus dosage likely needs to be adjusted to induce replication and protection in a higher percentage of vaccinated pigs.

CXCL9: evidence and contradictions for its role in tumor progression

Chemokines are a group of low molecular weight peptides. Their major function is the recruitment of leukocytes to inflammation sites, but they also play a key role in tumor growth, angiogenesis, and metastasis. In the last few years, accumulated experimental evidence supports that monokine induced by interferon (IFN)‐gamma (CXCL9), a member of CXC chemokine family and known to attract CXCR3‐ (CXCR3‐A and CXCR3‐B) T lymphocytes, is involved in the pathogenesis of a variety of physiologic diseases during their initiation and their maintenance. This review for the first time presents the most comprehensive summary for the role of CXCL9 in different types of tumors, and demonstrates its contradictory role of CXCL9 in tumor progression. Altogether, this is a useful resource for researchers investigating therapeutic opportunities for cancer.

[HER-2 expression and clinical significance in esophagogastric junction adenocarcinoma (Siewert type Ⅱ)]

OBJECTIVE

To investigate the human epidermal growth factor receptor-2 (HER-2) expression in esophagogastirc junction adenocarcinoma(Siewert type Ⅱ)and its clinical significance.

METHODS

A total of 180 patients with esophagogastric junction adenocarcinoma (Siewert type Ⅱ) were included in this study. The HER-2 expression was detected by immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH) analysis was performed to assess the HER-2 gene amplification in the IHC-positive and IHC-weak positive cases.

RESULTS

HER-2 overexpression (3+ ), weak positive (2+ ) and negative (1+ /0) was 11.7%(21/180), 8.9%(16/180), and 79.4%(143/180), respectively. The FISH analysis showed HER-2 gene amplification in 95.2%(20/21) of HER-2(3+ ) cases and 18.8% (3/16) of HER-2(2+ ) cases. The concordance rate between IHC and FISH was 95.2%. Overexpression of HER-2(3+ ) was associated with the tumor differentiation (P<0.05), and irrelevant to age, sex, pT stage, pN stage, pM stage and pTNM stage (P>0.05). The median overall survival time (OS) was 13 months in HER-2(3+ ) patients, significantly shorter than the 21 months in HER-2(2+ ) and HER-2(+ /-) cases (P<0.01).

CONCLUSIONS

Approximately 11.7% of the patients with esophagogastric junction adenocarcinoma (Siewert type Ⅱ) are HER-2-positive on IHC. HER-2 overexpression is associated with the tumor differentiation. IHC can be used as a screening test for the positive expression of HER-2 in the esophagogastirc junction adenocarcinoma (Siewert type Ⅱ). However, FISH detection can be used as a more reliable detection method.

Ménétrier disease manifested by polyposis and involved in both the small bowel and entire colon: A Case Report

INTRODUCTION

Ménétrier disease (MD) is rare that is involved in both the small bowel and entire colon.

THE MAIN SYMPTOMS AND THE IMPORTANT CLINICAL FINDINGS

We describe a case of a 76-year-old male patient whose clinical presentations include intermittent diarrhea, epigastric pain, nausea, vomiting, asitia, and weight loss. An endoscopy was performed showing a large number of irregular forms and different sizes of polypoid lesions in the gastrointestinal tract, which is rare for MD.

THE MAIN DIAGNOSES, THERAPEUTICS INTERVENTIONS, AND OUTCOMES

Herein, this case was diagnosed as MD, mainly dependent on endoscopic evaluation, typical clinical symptoms, and histopathological examination of biopsy. As this patient was also infected with Helicobacter pylori, the eradication of H pylori was administered. Meanwhile, a high-protein diet was enjoined, the aforementioned patient's symptoms were alleviated evidently after 1 month.

CONCLUSION

Although the etiology of MD remained undetermined, we showed that eradication of H pylori in this case might contribute to the disease remission. This study enlarged the present understanding of MD.

Interleukin-8 Induces Expression of FOXC1 to Promote Transactivation of CXCR1 and CCL2 in Hepatocellular Carcinoma Cell Lines and Formation of Metastases in Mice

BACKGROUND & AIMS

Inflammation regulated by interleukin (IL) 8 promotes metastasis of hepatocellular carcinoma (HCC). The transcription factor forkhead box C1 (FOXC1) promotes metastasis by activating the epithelial to mesenchymal transition; its levels in liver tumors have been associated with shorter survival times of patients. We investigated whether FOXC1 activates inflammation signaling pathways in HCC cell lines.

METHODS

We performed studies in the human HCC cell lines Huh-7 and SMMC7721, as well as the metastatic cell lines MHCC97H and HCCLM3. Cell lines were incubated with IL8 and transcription of reporter genes was measured; cells were also incubated with kinase inhibitors. Levels of FOXC1 or IL8 were knocked down with small interfering messenger RNAs in Huh7 cells; cells were analyzed in vitro in migration and invasion assays. To study metastasis, HCC cells were injected into flanks of BALB/C nude mice; 4 weeks later, the subcutaneous tumor fragments were collected and implanted into livers of the nude mice, and number and size tumors formed were measured. Chromatin immunoprecipitation assays were used to measure binding of transcription factors promoter regions of genes. We measured levels of FOXC1, IL8, CXCR1, and CCL2 in 2 groups of human HCC tissues collected from the Xijing or Tongji Hospitals in China (n = 690 and n = 312 samples, respectively) using immunohistochemistry.

RESULTS

Incubation of HCC cells with IL8 led to increased expression of FOXC1, via activation of phosphoinositide 3-kinase signaling to AKT and hypoxia-inducible factor 1α. Knockdown of FOXC1 in HCC cells that overexpressed IL8 reduced the numbers of metastases formed in mice, compared with cells without FOXC1 knockdown. Transgenic overexpression of FOXC1 in HCC cells with IL8 knockdown increased the numbers of metastases formed in mice compared with cells without FOXC1 overexpression. CXCR1 and CCL2 were direct transcriptional targets of FOXC1. Knockdown of the combination of CXCR1 and CCL2 reduced the invasive activities of HCC cells that overexpress FOXC1 and formation of lung metastases in mice, and transgenic overexpression of CXCR1 increased cell's invasive and metastatic abilities after knockdown of FOXC1. Liver metastases grown from cells that overexpressed FOXC1 were infiltrated by tumor-associated macrophages, and CCL2 knockdown decreased tumor-associated macrophage infiltration; depletion of macrophages from mice significantly reduced growth of metastases by cells that overexpressed FOXC1. In human HCC tissues, level of FOXC1 correlated with levels of IL8 and CXCR1 and CCL2 and infiltration of tumors by macrophage. In multivariate analysis, detection of FOXC1 and CCL2 were independent predictors for postoperative recurrence of HCC and overall survival.

CONCLUSIONS

In HCC cell lines, IL8 activates expression of FOXC1 via the phosphoinositide 3-kinase signaling to AKT and hypoxia-inducible factor 1α. FOXC1 expression leads to transactivation of CXCR1 and CCL2, promoting inflammation and the invasive and metastatic abilities of HCC cells.

Histidine-rich calcium binding protein promotes growth of hepatocellular carcinoma in vitro and in vivo

We have recently shown that the histidine-rich calcium binding protein (HRC) promotes the invasion and metastasis of hepatocellular carcinoma (HCC). In the current study, we evaluated whether HRC may also affect the growth of HCC. We found that ectopic expression of HRC obviously enhanced proliferation and colony formation, while suppression of HRC exhibited inhibitory effects. Furthermore, we demonstrated that HRC promoted tumor growth in nude mice. These effects may result from the ability of HRC to upregulate cyclinD1 and cyclin-dependent kinase 2 (CDK2) expressions and promote G1/S transition. Further study showed that MEK/ERK signaling pathway was involved in HRC-induced cell proliferation. Interestingly, overexpression or depletion of HRC revealed its regulation on endoplasmic reticulum stress (ERS) and apoptosis, which was partially dependent on PERK/ATF4/CHOP signaling pathway. In addition, blocking ERS using 4-phenylbutyric acid (4-PBA) not only downregulated the expression of PERK, ATF4 and CHOP, but also significantly decreased apoptosis induced by HRC silence, whereas ERS inducer thapsigargin (TG) exerted the opposite effects. Our study thus demonstrates a role of HRC in promoting HCC growth, besides its role in inducing HCC metastasis, and highlights HRC as a promising intervention target for HCC.

Sodium Ferulate Reduces Portal Pressure Through Inhibition of RhoA/Rho-Kinase and Activation of Endothelial Nitric Oxide Synthase in Cirrhotic Rats

BACKGROUND AND AIMS

Recent studies have demonstrated that increased RhoA/Rho-kinase activity and reduced nitric oxide activity have the necessary machinery to induce cirrhosis. However, it is unclear whether this regulates the functions of hepatic stellate cells (HSCs). In this study, we used sodium ferulate (SF) in a cirrhotic rat model and examined its roles in regulating RhoA activation in HSCs and the subsequent effects on contraction of HSCs.

METHODS

Bile duct ligation method was used to induce cirrhosis in rats. Intrahepatic resistance was investigated in in situ perfused livers. Hepatic RhoA, Rho-kinase and eNOS expressions were studied by RT-PCR and Western blot. RhoA pull-down assay and collagen gel contraction assay of HSCs were performed by incubation with SF in the absence or presence of GGPP.

RESULTS

We showed that in cirrhotic liver, SF can efficiently affect RhoA activation via lowering the synthesis of GGPP in HSCs. These actions effectively reduced basal intrahepatic resistance in cirrhotic rats. Our study further suggested that SF effectively decreased Rho-kinase activity and increased activity of eNOS at both the mRNA and protein levels. SF treatment of HSCs reduced RhoA GTP without affecting the total RhoA protein level, and GGPP had the ability to block SF-induced protein expression. Furthermore, SF inhibited the contraction of activated HSCs and this inhibition was efficiently reversed by addition of GGPP.

CONCLUSIONS

SF inhibits hepatic RhoA/Rho-kinase signaling and activates the NO/PKG pathway in cirrhotic rats. This may serve as a mechanism for reducing the contraction of activated HSCs upon SF treatment.

Hypoxia induced HMGB1 and mitochondrial DNA interactions mediate tumor growth in hepatocellular carcinoma through Toll-like receptor 9

BACKGROUND & AIMS

The mechanisms of hypoxia-induced tumor growth remain unclear. Hypoxia induces intracellular translocation and release of a variety of damage associated molecular patterns (DAMPs) such as nuclear HMGB1 and mitochondrial DNA (mtDNA). In inflammation, Toll-like receptor (TLR)-9 activation by DNA-containing immune complexes has been shown to be mediated by HMGB1. We thus hypothesize that HMGB1 binds mtDNA in the cytoplasm of hypoxic tumor cells and promotes tumor growth through activating TLR9 signaling pathways.

METHODS

C57BL6 mice were injected with Hepa1-6 cancer cells. TLR9 and HMGB1 were inhibited using shRNA or direct antagonists. HuH7 and Hepa1-6 cancer cells were investigated in vitro to determine how the interaction of HMGB1 and mtDNA activates TLR9 signaling pathways.

RESULTS

During hypoxia, HMGB1 translocates from the nucleus to the cytosol and binds to mtDNA released from damaged mitochondria. This complex subsequently activates TLR9 signaling pathways to promote tumor cell proliferation. Loss of HMGB1 or mtDNA leads to a defect in TLR9 signaling pathways in response to hypoxia, resulting in decreased tumor cell proliferation. Also, the addition of HMGB1 and mtDNA leads to the activation of TLR9 and subsequent tumor cell proliferation. Moreover, TLR9 is overexpressed in both hypoxic tumor cells in vitro and in human hepatocellular cancer (HCC) specimens; and, injection in mice to knockdown either HMGB1 or TLR9 from HCC cells suppressed tumor growth in vivo.

CONCLUSIONS

Our data reveals a novel mechanism by which the interactions of HMGB1 and mtDNA activate TLR9 signaling during hypoxia to induce tumor growth.

Sox12, a direct target of FoxQ1, promotes hepatocellular carcinoma metastasis through up-regulating Twist1 and FGFBP1

Metastasis is the main reason for high recurrence and poor survival of hepatocellular carcinoma (HCC) after curative resection. However, the molecular mechanism underlying HCC metastasis remains unclear. Here, we report on a novel function of SRY (sex determining region Y)-box 12 (Sox12), a member of the SYR-related high mobility group box family proteins, in promoting HCC metastasis. Overexpression of Sox12 was significantly correlated with loss of tumor encapsulation, microvascular invasion, and a higher tumor-nodule-metastasis (TNM) stage and indicated poor prognosis in human HCC patients. Sox12 expression was an independent and significant risk factor for recurrence and reduced survival after curative resection. Overexpression of Sox12 induced epithelial-mesenchymal transition by transactivating Twist1 expression. Down-regulation of Twist1 decreased Sox12-enhanced HCC migration, invasion, and metastasis, whereas up-regulation of Twist1 rescued the decreased migration, invasion, and metastasis induced by Sox12 knockdown. Additionally, serial deletion, site-directed mutagenesis, and chromatin immunoprecipitation assays showed that fibroblast growth factor binding protein 1 (FGFBP1) was a direct transcriptional target of Sox12. Knockdown of FGFBP1 decreased Sox12-mediated HCC invasion and metastasis, whereas overexpression of FGFBP1 rescued the decreased invasion and metastasis induced by Sox12 knockdown. Furthermore, forkhead box Q1 (FoxQ1) directly bound to the Sox12 promoter and transactivated its expression, which contributed to Sox12 overexpression in human HCC. Knockdown of Sox12 dramatically decreased FoxQ1-mediated HCC metastasis. In two independent cohorts of human HCC tissues, Sox12 expression was positively correlated with Twist1, FGFBP1, and FoxQ1 expression, and patients with positive coexpression of Sox12/Twist1, Sox12/FGFBP1, or FoxQ1/Sox12 were associated with poorer prognosis.

CONCLUSION

Up-regulated Sox12 induced by FoxQ1 promotes HCC invasion and metastasis by transactivating Twist1 and FGFBP1 expression. Thus, our study implicates Sox12 as a potential prognostic biomarker and a novel therapeutic target for HCC.

Suppressive effect of SATB1 on hepatic stellate cell activation and liver fibrosis in rats

Liver fibrosis is a worldwide clinical issue. Activation of hepatic stellate cells (HSCs) is the central event during liver fibrosis. We investigated the role of SATB1 in HSC activation and liver fibrogenesis. The results show that SATB1 expression is reduced during HSC activation. Additionally, SATB1 inhibits HSC activation, proliferation, migration, and collagen synthesis. Furthermore, CTGF, a pro-fibrotic agent, is also significantly inhibited by SATB1 through the Ras/Raf-1/MEK/ERK/Ets-1 pathway. In vivo, SATB1 deactivates HSCs and attenuates fibrosis in TAA-induced fibrotic rat livers. These data indicate that SATB1 plays an important role in HSC activation and liver fibrosis.

Netrin-1 promotes cell migration and invasion by down-regulation of BVES expression in human hepatocellular carcinoma

The axon guidance cues netrin-1 has been reported to be associated with cancer progression in various types of human cancers. However, the underlying molecular mechanism of netrin-1-mediated metastasis remains obscure. In this study, we found that overexpression of netrin-1 promoted HCC cell migration and invasion as determined by transwell assay and 3D cell culture assay. However, netrin-1 knockdown inhibited these processes. Further investigation indicated that netrin-1 decreased the expression of Blood Vessel Epicardial Substance (BVES), which was down-regulated in HCC. Interestingly, LY294002, a special inhibitor to PI3K/AKT signaling which was determined as a downstream pathway of netrin-1, restored the reduction in BVES caused by netrin-1. In addition, BVES exhibited an opposite effect on HCC cell metastasis to that of netrin-1. Importantly, up-regulating BVES expression significantly attenuated netrin-1-enhanced migration and invasion, whereas silencing BVES expression rescued the metastatic phenotype in netrin-1 knockdown cells. Moreover, netrin-1 expression was negatively correlated with BVES in HCC tissues and cell lines with different metastatic potential. Taken together, these results reveal that netrin-1 promotes HCC cell metastasis by regulating BVES expression via AKT activation.

Association of roasting meat intake with the risk of esophageal squamous cell carcinoma of Kazakh Chinese via affecting promoter methylation of p16 gene

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) incidence is high in Kazak Autonomous Prefecture, Xinjiang, China. Roasting food has been reported to be related with the risk of various cancers and is very popular in the area, and may be related with the risk of ESCC. The promoter methylation inactivation of p16 gene can increase the risk of ESCC. Thus, we want to know whether long-term roasting food is related with the risk of ESCC by effecting the promoter methylation of p16 gene.

MATERIALS AND METHODS

Ninety ESCC patients and 60 healthy subjects were recruited from Kazak Autonomous Prefecture. MassARRAY was used to detect p16 promoter methylation in ESCC tissues, as well as in normal esophageal tissues. The association between the p16 promoter methylation and daily roasting meat intake was examined.

RESULTS

Daily roasting meat intake was related with the risk of ESCC (p<0.01) and the mean CpG methylation rates of p16 promoter (p<0.01). In ESCC patients, the mean methylation rates of CpG 11-12 and CpG 33-34-35 were 29.4% and 37.4%, respectively, which was significantly higher than the rates in normal esophageal tissues (16.7% and 12.4%, respectively; p<0.01). The methylation of p16 promoter is also related with daily roasting meat intake (p<0.01) in Kazakh Chinese with ESCC. For the CpG methylation of the p16 promoter in the well, moderately and poorly differentiated ESCC, there are significant differences (p<0.05) for the 19 CpG units in the ESCC and controls.

CONCLUSION

Roasting meat intake was associated with the risk of ESCC via effects on the methylation of p16 promoter. These results suggest roasting food intake should be limited in the diet.

Netrin-1 induces epithelial-mesenchymal transition and promotes hepatocellular carcinoma invasiveness

BACKGROUND

Hypoxia is often found in solid tumors and is associated with tumor progression and poor clinical outcomes. We elucidated the mechanism by which netrin-1 released under hypoxic stress can induce epithelial-mesenchymal transition (EMT) to promote invasion in hepatocellular carcinoma (HCC) cells.

METHODS

The expression of netrin-1 and the dependent receptors UNC5H and deleted in colorectal cancer (DCC) in HCC was examined by immunohistochemistry or western blot. The HepG2 cells were cultured in 21% O2 (normoxia) or 1% O2 (hypoxia) for 24 h. The release of netrin-1 from hypoxic cells was detected by ELISA. Expression of E-cadherin and vimentin were examined by western blot. Inverted microscopy or confocal microscopy was used to show the cell morphology or cytoskeletal rearrangements. Cell invasion induced by hypoxia was analyzed by Transwell chamber. Cytokine IL-8 and IL-10 mRNA levels were assessed by real-time PCR.

RESULTS

The expression of netrin-1 was increased in HCC tissue and cell lines. The dependent receptors UNC5H and DCC were decreased in most HCC cell lines. Hypoxia induced netrin-1 release in a time-dependent manner. EMT induction was found to occur in hypoxic HCC cells in a process that was dependent on the extracellular release of netrin-1. Moreover, overexpression of netrin-1 resulted in EMT induction in normoxic tumor cells. Cytoskeletal rearrangements were found to occur and cell invasion was increased in cells with netrin-1 overexpression. Lastly, mRNA of IL-8 and IL-10 were also increased after recombinant human netrin-1 treatment.

CONCLUSION

These results suggest that in hypoxic HCC cells, netrin-1 activates downstream signaling pathways to induce EMT activation with subsequent production of multiple inflammatory mediators which in turn promotes cancer invasion.

BVES inhibition triggers epithelial-mesenchymal transition in human hepatocellular carcinoma

BACKGROUND/AIM

Metastasis contributes to the poor prognosis of hepatocellular carcinoma (HCC). However, the mechanism through which a primary HCC cell develops into a metastatic phenotype is not well understood. In this study, we set out to elucidate how blood vessel epicardial substance (BVES), a novel adhesion molecule regulating tight junction formation, mediates invasion and metastasis in human HCC cells.

METHODS

qRT-PCR, western blot and IHC were used to detect the expression of BVES in HCC samples and HCC cell lines. Small interfering RNAs (siRNAs) against human BVES were synthesized and used to transfect Huh7 cells. Then, the interference efficiency and the expression of mesenchymal marker vimentin and epithelial marker E-cadherin were measured by qRT-PCR and western blot. F-actin cytoskeleton was detected using TRITC-conjugated phalloidin. After inhibition of BVES, wound healing experiment and transwell assay were used to analyze the migratory and invasive ability of Huh7 cells.

RESULTS

BVES was down-regulated in human HCC tissues and HCC cell lines with high metastatic potential. After BVES inhibition, Huh7 cells exhibited some morphological changes including cytoskeleton rearrangement and junctional disruption. Cell migration and invasion were increased concomitant with increased expression of vimentin, IL-6, MMP2, MMP9 and decreased expression of E-cadherin. Finally, we found the expression of epithelial-mesenchymal transition (EMT) transcription factors Snail1 and Twist1 was significantly increased in BVES knockdown cells.

CONCLUSIONS

Our results suggest that down-regulation of BVES in HCC induces EMT, thus promoting invasion and metastasis in HCC cells.