Project description:Identification of genetic/cytogenetic alterations and differentially expressed cellular genes in HPV16 E6, E7 and E6/E7 positive human foreskin keratinocytes Keywords: ordered We used microarrays to identify differentially expressed genes in human foreskin keratinocytes (HFK) transfected with retroviral vectors harboring the human papillomavirus type 16 oncogenes E6, E7, or E6/E7 in comparison to HFK containing the empty vector control pLXSN.
Project description:Specific types of human papillomaviruses (HPVs) cause cervical cancer, the second most common tumor in females worldwide. Both cellular transformation and the maintenance of the oncogenic phenotype of HPV-positive tumor cells are linked to the expression of the viral E6 and E7 oncogenes. In order to identify downstream cellular target genes for the viral oncoproteins, we silenced endogenous E6 and E7 expression in HPV-positive HeLa cells by RNA interference (RNAi). Subsequently, we assessed changes of the cellular transcriptome by genome-wide microarray analysis. We identified, 648 genes wich were either downregulated (360 genes) or upregulated (288 genes) upon inhibition of E6/E7 expression. A large fraction of these genes is involved in tumour-relevant processes, such as apoptosis control, cell cycle regulation, or spindle formation. Others may represent novel cellular targets for the HPV oncogenes, such as a large group of C-MYC-associated genes involved in RNA splicing. Keywords: siRNA mediated knockdown
Project description:The human papillomavirus virus (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 gene expression profile of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins. Gene expression profile of SCLC has been performed using Agilent whole mouse genome (4x44k) representing ~ 41000 genes and mouse transcripts. Samples were obtained from two HPV16-E6/E7 transgenic mouse model and from littermateM-bM-^@M-^Ys normal lung.
Project description:Human papillomavirus (HPV) genome integration into the host genome, blocking E2 expression and leading to overexpression of E6 and E7 viral oncogenes, is considered a major step in cervical cancer development. In high-risk HPVs, E6 and E7 oncogenes are expressed as a bicistronic pre-mRNA, with alternative splicing producing the ultimate mRNAs required for E6 and E7 translation. Given the number of alternative donor and acceptor splicing sites, ten E6/E7 different alternative transcripts might be formed for HPV16 and three for HPV18, although only six isoforms have been previously reported for HPV16. In the present work, we employ high-throughput sequencing of invasive cervical cancer transcriptome (RNA-Seq) to characterize the expression of the HPV genome in 24 invasive cervical cancers associated with HPV16 and HPV18 single infections. Based on high-resolution transcriptional maps, we herein report three viral gene expression patterns which might be associated with the presence of the viral genome in episomal and/or integrated stages. Alternative mRNAs splicing isoforms coding for E6 and E7 oncoproteins were characterized and quantified, and two novel isoforms were identified. Three major isoforms (E6*I, E6*II, and E6+E7) were detected for HPV16 and two for HPV18 (E6*I and E6+E7). Minor transcript isoforms, including the novel ones, were very rare in some tumor samples or were not detected. Our data suggested that minor transcript isoforms of E6/E7 do not play a relevant role in cervical cancer.
Project description:The life cycle of human papillomaviruses (HPV) is strictly linked to the differentiation of their natural host cells. The HPV E6 and E7 oncoproteins can delay the normal differentiation program of keratinocytes, however, the exact mechanisms responsible for this have not yet been identified. The goal of this study was to investigate the effects of HPV16 oncoproteins on the expression of genes involved in keratinocyte differentiation. Primary human keratinocytes transduced by LXSN (control) retroviruses or virus vectors expressing HPV16 E6, E7 or E6/E7 genes were subjected to gene expression profiling. The results of microarray analysis showed that HPV 16 E6 and E7 have the capacity to down-regulate the expression of several genes involved in keratinocyte differentiation. Quantitative real-time polymerase chain reaction (qRT-PCR) assays were performed to confirm microarray data. To investigate the effects of the HPV oncoproteins on the promoters of selected keratinocyte differentiation genes, luciferase reporter assays were performed. Our results suggest that the HPV 16 E6 and/or E7 oncogenes are able to down-regulate the expression of several genes involved in keratinocyte differentiation, at least partially by down-regulating their promoter activity. This activity of the HPV oncoproteins may have a role in the productive virus life cycle, and also in virus induced carcinogenesis. Primary human foreskin keratinocytes were transduced by retrovirus vectors containing HPV 16 E6, E7, E6/E7 or the control vector LXSN. The global gene expression patterns of transduced keratinocytes were analyzed on Affymetrix microarrays
Project description:Human papillomavirus (HPV) E6 and E7 oncoproteins are expressed at all stages of HPV-mediated carcinogenesis and are essential drivers of cancers caused by high-risk HPV. Some of the activities of HPV E6 and E7, such as their interactions with host cellular tumor suppressors, have been characterized extensively. There is less information about how high-risk HPV E6 and E7 alter cellular responses to cytokines that are present in HPV-infected tissues and are an important component of the tumor microenvironment. We used several models of HPV oncoprotein activity to assess how E6 and E7 alter the cellular response to the pro-inflammatory cytokine IL-1beta. Models of early-stage HPV infection (human keratinocytes expressing HPV16 E6 and E7) and models of established HPV-positive head and neck cancers (patient-derived xenografts, head and neck cancer cell lines) exhibited similar dysregulation of IL-1 pathway genes and suppressed responses to IL-1beta treatment. Such overlap in cell responses supports that changes induced by HPV E6 and E7 early in infection could persist and contribute to a dysregulated immune environment throughout carcinogenesis. HPV E6 and E7 also drove the upregulation of several suppressors of IL-1 cytokine signaling, including SIGIRR, both in primary keratinocytes and in cancer cells. SIGIRR knockout was insufficient to increase IL-1beta-dependent gene expression in the presence of HPV16 E6 and E7, suggesting that multiple suppressors of IL-1 signaling contribute to dampened IL-1 responses in HPV16-positive cells.
Project description:The human papillomavirus virus (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 gene expression profile of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins.
Project description:The life cycle of human papillomaviruses (HPV) is strictly linked to the differentiation of their natural host cells. The HPV E6 and E7 oncoproteins can delay the normal differentiation program of keratinocytes, however, the exact mechanisms responsible for this have not yet been identified. The goal of this study was to investigate the effects of HPV16 oncoproteins on the expression of genes involved in keratinocyte differentiation. Primary human keratinocytes transduced by LXSN (control) retroviruses or virus vectors expressing HPV16 E6, E7 or E6/E7 genes were subjected to gene expression profiling. The results of microarray analysis showed that HPV 16 E6 and E7 have the capacity to down-regulate the expression of several genes involved in keratinocyte differentiation. Quantitative real-time polymerase chain reaction (qRT-PCR) assays were performed to confirm microarray data. To investigate the effects of the HPV oncoproteins on the promoters of selected keratinocyte differentiation genes, luciferase reporter assays were performed. Our results suggest that the HPV 16 E6 and/or E7 oncogenes are able to down-regulate the expression of several genes involved in keratinocyte differentiation, at least partially by down-regulating their promoter activity. This activity of the HPV oncoproteins may have a role in the productive virus life cycle, and also in virus induced carcinogenesis.
Project description:The infection with high-risk human papillomavirus is aetiologically linked to cervical cancer, the role of miRNAs regulated by virus oncogene in cancer progression remain largely unknown. Here, we screened the differentially expressed miRNAs with miRNA array between virus oncogene e6/e7 silenced and not in HPV16-positive cervical cancer cell lines In the study, we screened the differentially expressed miRNAs with miRNA array (Exiqon, miRCURY LNA microRNA array, 7th gen [hsa, miRBase 18]) between virus oncogene e6/e7 silenced and not in HPV16-positive cervical cancer cell lines to found miRNAs regulated by virus oncogene e6/e7. Biological replicates: 3 control, 3 e6/e7 silenced, independently grown and harvested. four replicates per array.
Project description:Aberrant glycosylation is a characteristic of tumor cells. The expression of certain glycan structures has been associated with poor prognosis. In cervical carcinoma has been reported changes in the gene expression level of some glycogenes that has been associated with lymph invasion. Human papilloma virus (HPV) infection is one of the most important factors to develop cervical cancer. HPV oncoproteins E6 and E7 have been implicated in cervical carcinogenesis. The role of these oncoproteins in glycosylation changes has not been reported. To know the effect of these oncoproteins on glycogene expression we realized a partial silencing of oncogenes E6 and E7 in HeLa cells, we made a microarray expression assay and we identified glycogenes that modified its expression. The analysis showed alteration in some glycosylation pathways, like glycosphingolipid, O-glycan mucin-type, and O-glycan non mucin-type glycosylation. Our results suggest that E6 and E7 oncoproteins could modified glycosylation of structures implicated in proliferation, adhesion, and apoptosis.