Molecular mechanisms of constitutive and inducible NF-kappaB activation in oesophageal adenocarcinoma

The Association between Dietary Vitamin C Intake and the Risk of Esophageal Cancer: An Updated Dose-Response Meta-Analysis

Although some epidemiological studies have reported the associations between vitamin C and risk of esophageal cancer, these results are inconsistent. Therefore, we performed an updated meta-analysis to explore the associations between dietary vitamin C intake and risk of esophageal cancer. We used PubMed, Embase, and the Web of Science to screen all published articles, which yielded 18 papers eligible for data extraction (involving 4,126 cases and 36,902 controls), and then pooled the odds ratios (ORs) and corresponding 95% confidence intervals (CIs) using random-effects model. As we detected the associations in highest category and the lowest type of dietary vitamin C intake, we discovered that dietary vitamin C intake was negatively correlated to the risk of esophageal cancer. The analysis of subgroup showed a significant counter proportion between vitamin C and the risk of ESCC and EAC. Moreover, the dose-analysis indicated that if increasing dietary intake of vitamin C of 50 mg/day, esophageal cancer risk dropped down 10% (OR = 0.81, 95%CI: 0.75-0.87). In summary, our study provides a comprehensive and updated epidemiological evidence to elucidate the relationships between dietary vitamin C and reduction of esophageal cancer risk. Nevertheless, we still need larger case-control and cohort studies to confirm these connections.

Akt+ IKKα/β+ Rab5+ Signalosome Mediate the Endosomal Recruitment of Sec61 and Contribute to Cross-Presentation in Bone Marrow Precursor Cells

Cross-presentation in dendritic cells (DC) requires the endosomal relocations of internalized antigens and the endoplasmic reticulum protein Sec61. Despite the fact that endotoxin-containing pathogen and endotoxin-free antigen have different effects on protein kinase B (Akt) and I-kappa B Kinase α/β (IKKα/β) activation, the exact roles of Akt phosphorylation, IKKα or IKKβ activation in endotoxin-containing pathogen-derived cross-presentation are poorly understood. In this study, endotoxin-free ovalbumin supplemented with endotoxin was used as a model pathogen. We investigated the effects of endotoxin-containing pathogen and endotoxin-free antigen on Akt phosphorylation, IKKα/β activation, and explored the mechanisms that the endotoxin-containing pathogen orchestrating the endosomal recruitment of Sec61 of the cross-presentation in bone marrow precursor cells (BMPC). We demonstrated that endotoxin-containing pathogen and endotoxin-free antigen efficiently induced the phosphorylation of Akt-IKKα/β and Akt-IKKα, respectively. Endotoxin-containing pathogen derived Akt+ IKKα/β+ Rab5+ signalosome, together with augmented the recruitment of Sec61 toward endosome, lead to the increased cross-presentation in BMPC. Importantly, the endosomal recruitment of Sec61 was partly mediated by the formation of Akt+ IKKα/β+ signalosome. Thus, these data suggest that Akt+ IKKα/β+ Rab5+ signalosome contribute to endotoxin-containing pathogen-induced the endosomal recruitment of Sec61 and the superior efficacy of cross-presentation in BMPC.

A phase I pilot study evaluating the beneficial effects of black raspberries in patients with Barrett's esophagus

Black raspberries inhibit a broad range of cancers in preclinical models which has led to clinical evaluations targeting premalignant lesions of the colon, oral cavity and esophagus. A phase I pilot study was conducted in twenty Barrett's esophagus (BE) patients to investigate the effect of lyophilized black raspberries (LBR) on urinary metabolites and markers of lipid peroxidation, DNA damage and tissue markers of cellular proliferation, detoxification, and inflammation. Surveys, biopsies, blood and urine samples were collected before and after 6 months of LBR treatment (32 or 45 g). LBR significantly reduced urinary excretion of 8-epi-prostaglandin F2α, a marker of lipid peroxidation linked to oxidative stress and free radical damage. Urinary levels of the ellagitannin metabolites, urolithin A-glucuronide, urolithin A-sulfate and dimethylellagic acid glucuronide were significantly increased following 12 and 26 weeks of LBR consumption and may prove useful as indicators of compliance in future clinical studies. Immunohistochemical staining of BE biopsies following LBR treatment showed significant increases in mean GST-pi levels, with 55.6% of subjects responding favorably. In summary, LBR significantly decreased urinary lipid peroxidation levels and significantly increased GST-pi, a marker of detoxification, in BE epithelium. Still, LBR may need to be formulated differently, administered at higher concentrations or multiple times a day to increase efficacy.

An update of the WCRF/AICR systematic literature review and meta-analysis on dietary and anthropometric factors and esophageal cancer risk

Background

In the 2007 World Cancer Research Fund/American Institute for Cancer Research Second Expert Report, the expert panel judged that there was strong evidence that alcoholic drinks and body fatness increased esophageal cancer risk, whereas fruits and vegetables probably decreased its risk. The judgments were mainly based on case–control studies. As part of the Continuous Update Project, we updated the scientific evidence accumulated from cohort studies in this topic.

Methods

We updated the Continuous Update Project database up to 10 January 2017 by searching in PubMed and conducted dose–response meta-analyses to estimate summary relative risks (RRs) and 95% confidence intervals (CIs) using random effects model.

Results

A total of 57 cohort studies were included in 13 meta-analyses. Esophageal adenocarcinoma risk was inversely related to vegetable intake (RR per 100 g/day: 0.89, 95% CI: 0.80–0.99, n = 3) and directly associated with body mass index (RR per 5 kg/m²: 1.47, 95% CI: 1.34–1.61, n = 9). For esophageal squamous cell carcinoma, inverse associations were observed with fruit intake (RR for 100 g/day increment: 0.84, 95% CI: 0.75–0.94, n = 3) and body mass index (RR for 5 kg/m² increment: 0.64, 95% CI: 0.56–0.73, n = 8), and direct associations with intakes of processed meats (RR for 50 g/day increment: 1.59, 95% CI: 1.11–2.28, n = 3), processed and red meats (RR for 100 g/day increment: 1.37, 95% CI: 1.04–1.82, n = 3) and alcohol (RR for 10 g/day increment: 1.25, 95% CI: 1.12–1.41, n = 6).

Conclusions

Evidence from cohort studies suggested a protective role of vegetables and body weight control in esophageal adenocarcinomas development. For squamous cell carcinomas, higher intakes of red and processed meats and alcohol may increase the risk, whereas fruits intake may play a protective role.

IKKα regulates the stratification and differentiation of the epidermis: implications for skin cancer development

IKKα plays a mandatory role in keratinocyte differentiation and exerts an important task in non-melanoma skin cancer development. However, it is not fully understood how IKKα exerts these functions. To analyze in detail the role of IKKα in epidermal stratification and differentiation, we have generated tridimensional (3D) cultures of human HaCaT keratinocytes and fibroblasts in fibrin gels, obtaining human skin equivalents that comprise an epidermal and a dermal compartments that resembles both the structure and differentiation of normal human skin. We have found that IKKα expression must be strictly regulated in epidermis, as alterations in its levels lead to histological defects and promote the development of malignant features. Specifically, we have found that the augmented expression of IKKα results in increased proliferation and clonogenicity of human keratinocytes, and leads to an accelerated and altered differentiation, augmented ability of invasive growth, induction of the expression of oncogenic proteins (Podoplanin, Snail, Cyclin D1) and increased extracellular matrix proteolytic activity. All these characteristics make keratinocytes overexpressing IKKα to be at a higher risk of developing skin cancer. Comparison of genetic profile obtained by analysis of microarrays of RNA of skin equivalents from both genotypes supports the above described findings.

Opposing effects of bile acids deoxycholic acid and ursodeoxycholic acid on signal transduction pathways in oesophageal cancer cells

Ursodeoxycholic acid (UDCA) was reported to reduce bile acid toxicity, but the mechanisms underlying its cytoprotective effects are not fully understood. The aim of the present study was to examine the effects of UDCA on the modulation of deoxycholic acid (DCA)-induced signal transduction in oesophageal cancer cells. Nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) activity was assessed using a gel shift assay. NF-κB activation and translocation was performed using an ELISA-based assay and immunofluorescence analysis. COX-2 expression was analysed by western blotting and COX-2 promoter activity was assessed by luciferase assay. DCA induced NF-κB and AP-1 DNA-binding activities in SKGT-4 and OE33 cells. UDCA pretreatment inhibited DCA-induced NF-κB and AP-1 activation and NF-κB translocation. This inhibitory effect was coupled with a blockade of IκB-α degradation and inhibition of phosphorylation of IKK-α/β and ERK1/2. Moreover, UDCA pretreatment inhibited COX-2 upregulation. Using transient transfection of the COX-2 promoter, UDCA pretreatment abrogated DCA-induced COX-2 promoter activation. In addition, UDCA protected oesophageal cells from the apoptotic effects of deoxycholate. Our findings indicate that UDCA inhibits DCA-induced signalling pathways in oesophageal cancer cells. These data indicate a possible mechanistic role for the chemopreventive actions of UDCA in oesophageal carcinogenesis.

The prognostic and clinicopathologic characteristics of CD147 and esophagus cancer: A meta-analysis

OBJECTIVE

The prognostic significance of CD147 expression in esophageal cancer patients remains controversial. Using a meta-analysis, we investigated the prognostic and clinicopathologic characteristics of CD147 in esophageal cancer.

METHODS

A comprehensive literature search of the PubMed (1966-2016), EMBASE (1980-2016), Cochrane Library (1996-2016), Web of Science (1945-2016), China National Knowledge Infrastructure (1982-2016), and Wanfang databases (1988-2016) was performed to identify studies of all esophageal cancer subtypes. Correlations between CD147 expression and survival outcomes and clinicopathological features were analyzed using meta-analysis methods.

RESULTS

Seventeen studies were included. High CD147 expression reduced the 3-year survival rate (OR = 3.26, 95% CI = (1.53, 6.93), p = 0.02) and 5-year survival rate(OR = 4.35, 95% CI = (2.13, 8.90), p < 0.0001). High CD147 expression reduced overall survival in esophageal cancer (HR = 1.60, 95% CI = (1.19, 2.15), p = 0.02). Additionally, higher CD147 expression was detected in esophageal cancer tissues than noncancerous tissues (OR = 9.45, 95% CI = (5.39, 16.59), p < 0.00001), normal tissues (OR = 12.73, 95% CI = (3.49, 46.46), p = 0.0001), para-carcinoma tissues (OR = 12.80, 95% CI = (6.57, 24.92), p < 0.00001), and hyperplastic tissues (OR = 3.27, 95% CI = (1.47, 7.29), p = 0.004). CD147 expression was associated with TNM stage (OR = 3.66, 95% CI = (2.20, 6.09), p < 0.00001), tumor depth (OR = 7.97, 95% CI = (4.13, 15.38), p < 0.00001), and lymph node status (OR = 5.14, 95% CI = (2.03,13.01), p = 0.0005), but not with tumor differentiation, age, or sex.

CONCLUSION

Our meta-analysis suggests that CD147 is an efficient prognostic factor in esophageal cancer. High CD147 expression in patients with esophageal cancer was associated with worse survival outcomes and common clinicopathological indicators of poor prognosis.

Cranberry proanthocyanidins inhibit esophageal adenocarcinoma in vitro and in vivo through pleiotropic cell death induction and PI3K/AKT/mTOR inactivation

Cranberries are rich in bioactive constituents known to improve urinary tract health and more recent evidence supports cranberries possess cancer inhibitory properties. However, mechanisms of cancer inhibition by cranberries remain to be elucidated, particularly in vivo. Properties of a purified cranberry-derived proanthocyanidin extract (C-PAC) were investigated utilizing acid-sensitive and acid-resistant human esophageal adenocarcinoma (EAC) cell lines and esophageal tumor xenografts in athymic NU/NU mice. C-PAC induced caspase-independent cell death mainly via autophagy and low levels of apoptosis in acid-sensitive JHAD1 and OE33 cells, but resulted in cellular necrosis in acid-resistant OE19 cells. Similarly, C-PAC induced necrosis in JHAD1 cells pushed to acid-resistance via repeated exposures to an acidified bile cocktail. C-PAC associated cell death involved PI3K/AKT/mTOR inactivation, pro-apoptotic protein induction (BAX, BAK1, deamidated BCL-xL, Cytochrome C, PARP), modulation of MAPKs (P-P38/P-JNK) and G_2-M cell cycle arrest in vitro. Importantly, oral delivery of C-PAC significantly inhibited OE19 tumor xenograft growth via modulation of AKT/mTOR/MAPK signaling and induction of the autophagic form of LC3B supporting in vivo efficacy against EAC for the first time. C-PAC is a potent inducer of EAC cell death and is efficacious in vivo at non-toxic behaviorally achievable concentrations, holding promise for preventive or therapeutic interventions in cohorts at increased risk for EAC, a rapidly rising and extremely deadly malignancy.

Sinapine reverses multi-drug resistance in MCF-7/dox cancer cells by downregulating FGFR4/FRS2α-ERK1/2 pathway-mediated NF-κB activation

BACKGROUND

Sinapine, an alkaloid derived from seeds of the cruciferous species, shows favorable biological properties, such as antioxidant and radio-protective activities. The inhibitory effect of sinapine on acquired chemoresistance in tumor cells and the underlying molecular mechanisms remain unknown.

AIM

We examined the effect of sinapine on reversal of chemoresistance in Michigan Cancer Foundation 7 (MCF-7)/dox breast cancer cells.

RESULTS

Combination treatment with sinapine and doxorubicin synergistically increased the cytotoxicity of doxorubicin in MCF-7/dox cells, as shown using a cell apoptosis assay. An accumulation assay demonstrated that sinapine increased the intracellular concentration of doxorubicin in a dose-dependent manner. Immunoblotting and real time polymerase chain reaction (RT-PCR) analysis showed that sinapine downregulated multi-drug resistance 1 (MDR1) expression. A significant correlation was observed between the expression of MDR1, phospho-factor receptor substrate (FRS), phospho-extracellular signal regulated kinase (ERK)1/2, and nuclear factor kappa B (NF-κB). Chromatin immunoprecipitation (ChIP) assay indicated that sinapine inhibited binding of the transcription factor NF-κB to the MDR1 promoter.

CONCLUSIONS

Our findings indicated that sinapine played an important role in the downregulation of MDR1 expression through suppression of fibroblast growth factor receptor (FGFR)4/FRS2α-ERK1/2 mediated NF-κB activation in MCF-7/dox cancer cells.