Involvement of aryl hydrocarbon receptor signaling in the development of small cell lung cancer induced by HPV E6/E7 oncoproteins

<p>Abstract</p> <p>Background</p> <p>Lung cancers consist of four major types that and for clinical-pathological reasons are often divided into two broad categories: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). All major histological types of lung cancer are associated with smoking, although the association is stronger for SCLC and squamous cell carcinoma than adenocarcinoma. To date, epidemiological studies have identified several environmental, genetic, hormonal and viral factors associated with lung cancer risk. It has been estimated that 15-25% of human cancers may have a viral etiology. The human papillomavirus (HPV) is a proven cause of most human cervical cancers, and might have a role in other malignancies including vulva, skin, oesophagus, head and neck cancer. HPV has also been speculated to have a role in the pathogenesis of lung cancer. To validate the hypothesis of HPV involvement in small cell lung cancer pathogenesis we performed a gene expression profile of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins.</p> <p>Methods</p> <p>Gene expression profile of SCLC has been performed using Agilent whole mouse genome (4 × 44k) representing ~ 41000 genes and mouse transcripts. Samples were obtained from two HPV16-E6/E7 transgenic mouse models and from littermate's normal lung. Data analyses were performed using GeneSpring 10 and the functional classification of deregulated genes was performed using Ingenuity Pathway Analysis (Ingenuity^®Systems, <url>http://www.ingenuity.com</url>).</p> <p>Results</p> <p>Analysis of deregulated genes induced by the expression of E6/E7 oncoproteins supports the hypothesis of a linkage between HPV infection and SCLC development. As a matter of fact, comparison of deregulated genes in our system and those in human SCLC showed that many of them are located in the Aryl Hydrocarbon Receptor Signal transduction pathway.</p> <p>Conclusions</p> <p>In this study, the global gene expression of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins led us to identification of several genes involved in SCLC tumor development. Furthermore, our study reveled that the Aryl Hydrocarbon Receptor Signaling is the primarily affected pathway by the E6/E7 oncoproteins expression and that this pathway is also deregulated in human SCLC. Our results provide the basis for the development of new therapeutic approaches against human SCLC.</p

The Omega-3 Fatty Acid DHA Down Regulates the Expression of Genes Associated with Breast and Colorectal Cancers - A Whole - Genome Microarray Analysis

Background: Inflammation is a critical component of tumor progression and many cancers arise from sites of infection, chronic injury, and inflammation, where immune cells secrete large amounts of pro-inflammatory cytokines able to recruit a wide range of immune cells. The aim of this study was to gain insights into the molecular basis of potential chemo preventive and therapeutic activities of the -3 fatty acid DHA. Methods and Materials: Human umbilical vein endothelial cells (HUVEC) were treated with 50 &#956;mol/L DHA for 48 hours and then stimulated with 5 ng/mL IL-1&#946; for 3 hours. Total RNA from treated cells and controls were extracted using the RNeasy mini kit from Qiagen. RNA samples were analyzed quantitatively and qualitatively with a NanoDrop Spectrophotometer and an Agilent Bioanalyzer. RNA was labeled using Agilent low RNA Input Fluorescent Linear Amplification kit and purified by Qiagen\u27s RNeasy mini spin column. Gene expression profile was then performed using an Agilent Whole Human Genome Oligo Microarray, covering 41K unique genes and transcripts. Slides were scanned and image data processed using the Agilent Feature Extraction software. The raw data were processed by GeneSpring? 10 and differentially expressed RNA identified with the Benjamini and Hochberg False Discovery Rate (p<0.05) test. Functional and network analyses were performed by Ingenuity Pathways version 8.0 Analysis. Results and Conclusion: The gene expression profile of HUVEC pre-treated with DHA and stimulated with IL-1 shows that fish oil regulates several cellular pathways. Among these DHA down regulates the expression of 18 genes associated to cancer. In particular DHA affects the expression of HSPB8 and SIK1, known to be associated with breast cancer and the down regulation of PDE5A and DNAJA1 involved in colorectal cancer. The outcome of this study is of great interest because of DHA implication in human breast and colorectal cancer prevention

Microarray Analysis of Human Umbilical Vein Endothelial Cells (HUVEC) Treated with the omega-3 Fatty Acid Docosahexaenoic Acid (DHA) Highlights New Anti-Atherosclerotic and Anti-Angiogenic Properties for Fish and Fish Oil

Background and Aim: High intakes of -3 fatty acids have been associated with systemic anti-inflammatory effects and cardiovascular protection, but the molecular basis responsible for these effects remains incompletely defined. Using a DNA microarray technology we investigated the early gene expression profile of human vascular endothelium conditioned by DHA under proinflammatory conditions. Materials and Methods: HUVEC were treated with 50 &#956;mol/L DHA for 48 hours and then stimulated with 5 ng/mL IL-1beta for 3 hours. Total RNA was extracted, and qualitatively and quantitatively analyzed with a NanoDrop Spectrophotometer and an Agilent Bioanalyzer before RNA labeling and purification. Gene expression profile was performed with an Agilent Whole Human Genome Oligo Microarray covering 41 000 unique genes and transcripts. Slides were scanned with the Agilent\u27s scanner and images processed using Agilent Feature Extraction software. The raw data were further processed with the GeneSpring? 10 software and differentially expressed RNA identified using Benjamini and Hochberg False Discovery Rate with a p-value <0.05. Functional and network analyses were identified by the Ingenuity Pathways version 8.0 Analysis. Results and Conclusions: IL-1 stimulation significantly changed the expression of 1474 genes: 815 resulted down-regulated while 659 resulted up-regulated. Focusing on the 659 IL-1-upregulated genes, we observed that DHA significantly attenuated the expression of 88 such genes. The application of the Ingenuity pathway analysis software allowed us to pinpoint immunological-, inflammatory and atherogenic-related pathways as the most affected. In particular, we identified new target molecules involved in atherosclerosis, including tubulin beta polypeptide[TUBB]2 A and phosphodiesterase [PDE]5A; and in angiogenesis, including transforming growth factor [TGF]-beta 2 and chemokine (C-X-C motif) ligand 10. In conclusion, DHA widely affects endothelial gene expression; the identification of novel genes susceptible to DHA will certainly improve our understanding of mechanisms by which fish oils may prevent or attenuate human chronic diseases including atherosclerosis

Transcriptome-based identification of new anti-anti-inflammatory and vasodilating properties of the n-3 fatty acid docosahexaenoic acid in vascular endothelial cell under proinflammatory conditions

High intakes of n-3 fatty acids exert anti-inflammatory effects and cardiovascular protection, but the underlying molecular basis is incompletely defined. By genome-wide analysis we searched for novel effects of docosahexaenoic acid (DHA) on gene expression and pathways in human vascular endothelium under pro-inflammatory conditions

Genes differentially expressed in DHA plus IL-1β- versus IL-1β-treated cells.

<p>F.C. = fold change; U.F. = Genes of unknown function.</p><p>Genes regulated agonistically with IL-1.</p><p>Genes differentially expressed in DHA plus IL-1β- versus IL-1β-treated cells.</p

Top ten signaling and metabolic pathways regulated by docosahexaenoic acid (DHA) in resting, unactivated conditions.

<p>For the functional categorization of genes the Fisher’s exact test was used to calculate a P value (shown as bars), indicating the probability that each biological function assigned to the network is due to chance alone. The ratio represents the number of differentially expressed genes in a given pathway divided by total number of genes making up that canonical pathway.</p

Genes differentially expressed in DHA plus IL-1β versus IL-1β-treated cells.

<p>F.C. = fold change; U.F. = Genes of unknown function.</p><p>Genes regulated antagonistically with IL-1β.</p><p>Genes differentially expressed in DHA plus IL-1β versus IL-1β-treated cells.</p