scholarly journals Nucleolin as Activator of Human Papillomavirus Type 18 Oncogene Transcription in Cervical Cancer

2002 ◽  
Vol 196 (8) ◽  
pp. 1067-1078 ◽  
Author(s):  
Edgar Grinstein ◽  
Peter Wernet ◽  
Peter J.F. Snijders ◽  
Frank Rösl ◽  
Inge Weinert ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
High Risk ◽  
Cancer Cells ◽  
Binding Activity ◽  
Human Papillomaviruses ◽  
Cervix Uteri ◽  
Cell Protein ◽  
Critical Event ◽  
Cervical Cancer Cells ◽  
E6 And E7

High risk human papillomaviruses (HPVs) are central to the development of cervical cancer and the deregulated expression of high risk HPV oncogenes is a critical event in this process. Here, we find that the cell protein nucleolin binds in a sequence-specific manner to the HPV18 enhancer. The DNA binding activity of nucleolin is primarily S phase specific, much like the transcription of the E6 and E7 oncoproteins of HPV18 in cervical cancer cells. Antisense inactivation of nucleolin blocks E6 and E7 oncogene transcription and selectively decreases HPV18+ cervical cancer cell growth. Furthermore, nucleolin controls the chromatin structure of the HPV18 enhancer. In contrast, HPV16 oncogene transcription and proliferation rates of HPV16+ SiHa cervical cancer cells are independent of nucleolin activity. Moreover, nucleolin expression is altered in HPV18+ precancerous and cancerous tissue from the cervix uteri. Whereas nucleolin was homogeneously distributed in the nuclei of normal epithelial cells, it showed a speckled nuclear phenotype in HPV18+ carcinomas. Thus, the host cell protein nucleolin is directly linked to HPV18-induced cervical carcinogenesis.

scholarly journals E6-mediated activation of JNK drives EGFR signalling to promote proliferation and viral oncoprotein expression in cervical cancer

2020 ◽  
Author(s):  
Ethan L. Morgan ◽  
James A. Scarth ◽  
Molly R. Patterson ◽  
Christopher W. Wasson ◽  
Georgia C. Hemingway ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Human Papillomaviruses ◽  
Signalling Pathway ◽  
Viral Oncoprotein ◽  
Hpv E6 ◽  
Cervical Cancer Cells ◽  
E6 And E7 ◽  
Novel Therapeutic

AbstractHuman papillomaviruses (HPV) are a major cause of malignancy worldwide, contributing to ~5% of all human cancers including almost all cases of cervical cancer and a growing number of ano-genital and oral cancers. HPV-induced malignancy is primarily driven by the viral oncogenes, E6 and E7, which manipulate host cellular pathways to increase cell proliferation and enhance cell survival, ultimately predisposing infected cells to malignant transformation. Consequently, a more detailed understanding of viral-host interactions in HPV-associated disease offers the potential to identify novel therapeutic targets. Here, we identify that the c-Jun N-terminal kinase (JNK) signalling pathway is activated in cervical disease and in cervical cancer. The HPV E6 oncogene induces JNK1/2 phosphorylation in a manner that requires the E6 PDZ binding motif. We show that blockade of JNK1/2 signalling using small molecule inhibitors, or knockdown of the canonical JNK substrate c-Jun, reduces cell proliferation and induces apoptosis in cervical cancer cells. We further demonstrate that this phenotype is at least partially driven by JNK-dependent activation of EGFR signalling via increased expression of EGFR and the EGFR ligands EGF and HB-EGF. JNK/c-Jun signalling promoted the invasive potential of cervical cancer cells and was required for the expression of the epithelial to mesenchymal transition (EMT)-associated transcription factor Slug and the mesenchymal marker Vimentin. Furthermore, JNK/c-Jun signalling is required for the constitutive expression of HPV E6 and E7, which are essential for cervical cancer cell growth and survival. Together, these data demonstrate a positive feedback loop between the EGFR signalling pathway and HPV E6/E7 expression, identifying a regulatory mechanism in which HPV drives EGFR signalling to promote proliferation, survival and EMT. Thus, our study has identified a novel therapeutic target that may be beneficial for the treatment of cervical cancer.

scholarly journals Disruption of repressive p130–DREAM complexes by human papillomavirus 16 E6/E7 oncoproteins is required for cell-cycle progression in cervical cancer cells

2011 ◽  
Vol 92 (11) ◽  
pp. 2620-2627 ◽  
Author(s):  
Nurshamimi Nor Rashid ◽  
Rohana Yusof ◽  
Roger J. Watson
Keyword(s):  
Cell Cycle ◽  
Cervical Cancer ◽  
Cancer Cells ◽  
Cell Cycle Progression ◽  
Human Papillomaviruses ◽  
G1 Arrest ◽  
Cycle Progression ◽  
Hpv16 E6 ◽  
Cervical Cancer Cells ◽  
E6 And E7

Human papillomaviruses (HPVs) with tropism for mucosal epithelia are the major aetiological factors in cervical cancer. Most cancers are associated with so-called high-risk HPV types, in particular HPV16, and constitutive expression of the HPV16 E6 and E7 oncoproteins is critical for malignant transformation in infected keratinocytes. E6 and E7 bind to and inactivate the cellular tumour suppressors p53 and Rb, respectively, thus delaying differentiation and inducing proliferation in suprabasal keratinocytes to enable HPV replication. One member of the Rb family, p130, appears to be a particularly important target for E7 in promoting S-phase entry. Recent evidence indicates that p130 regulates cell-cycle progression as part of a large protein complex termed DREAM. The composition of DREAM is cell cycle-regulated, associating with E2F4 and p130 in G0/G1 and with the B-myb transcription factor in S/G2. In this study, we addressed whether p130–DREAM is disrupted in HPV16-transformed cervical cancer cells and whether this is a critical function for E6/E7. We found that p130–DREAM was greatly diminished in HPV16-transformed cervical carcinoma cells (CaSki and SiHa) compared with control cell lines; however, when E6/E7 expression was targeted by specific small hairpin RNAs, p130–DREAM was reformed and the cell cycle was arrested. We further demonstrated that the profound G1 arrest in E7-depleted CaSki cells was dependent on p130–DREAM reformation by also targeting the expression of the DREAM component Lin-54 and p130. The results show that continued HPV16 E6/E7 expression is necessary in cervical cancer cells to prevent cell-cycle arrest by a repressive p130–DREAM complex.

scholarly journals Human Papillomavirus E6/E7 and Long Noncoding RNA TMPOP2 Mutually Upregulated Gene Expression in Cervical Cancer Cells

2019 ◽  
Vol 93 (8) ◽  
Author(s):  
Hongpeng He ◽  
Xiang Liu ◽  
Yue Liu ◽  
Mengmeng Zhang ◽  
Yongwei Lai ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Cervical Cancer ◽  
Human Papillomavirus ◽  
Cancer Cells ◽  
Long Noncoding Rna ◽  
Noncoding Rna ◽  
Human Papillomaviruses ◽  
Cervical Cancer Cells ◽  
E6 And E7

ABSTRACT TMPOP2 was previously suggested to be an oncogenic long noncoding RNA which is excessively expressed in cervical cancer cells and inhibits E-cadherin gene expression by recruiting transcription repressor EZH2 to the gene promoter. So far, the function and regulation of TMPOP2 in cervical cancer remain largely unknown. Herein, we found that TMPOP2 expression was correlated with human papillomavirus 16/18 (HPV16/18) E6 and E7 in cervical cancer cell lines CaSki and HeLa. Tumor suppressor p53, which is targeted for degradation by HPV16/18, was demonstrated to associate with two p53 response elements in the TMPOP2 promoter to repress the transcription of the TMPOP2 gene. Reciprocally, ectopic expression of TMPOP2 was demonstrated to sequester tumor repressor microRNAs (miRNAs) miR-375 and miR-139 which target HPV16/18 E6/E7 mRNA and resulted in an upregulation of HPV16/18 E6/E7 genes. Thereby, HPV16/18 E6/E7 and the long noncoding RNA (lncRNA) TMPOP2 form a positive feedback loop to mutually derepress gene expression in cervical cancer cells. Moreover, results of RNA sequencing and cell cycle analysis showed that knockdown of TMPOP2 impaired the expression of cell cycle genes, induced cell cycle arrest, and inhibited HeLa cell proliferation. Together, our results indicate that TMPOP2 and HPV16/18 E6/E7 mutually strengthen their expression in cervical cancer cells to enhance tumorigenic activities. IMPORTANCE Human papillomaviruses 16 and 18 (HPV16/18) are the main causative agents of cervical cancer. Viral proteins HPV16/18 E6 and E7 are constitutively expressed in cancer cells to maintain oncogenic phenotypes. Accumulating evidences suggest that HPVs are correlated with the deregulation of long noncoding RNAs (lncRNAs) in cervical cancer, although the mechanism was unexplored in most cases. TMPOP2 is a newly identified lncRNA excessively expressed in cervical cancer. However, the mechanism for the upregulation of TMPOP2 in cervical cancer cells remains largely unknown and its relationship with HPVs is still elusive. The significance of our research is in revealing the mutual upregulation of HPV16/18 E6/E7 and TMPOP2 with the molecular mechanisms explored. This study will expand our understandings of the oncogenic activities of human papillomaviruses and lncRNAs.

scholarly journals Adenoviral Vectors Armed with PAPILLOMAVIRUs Oncogene Specific CRISPR/Cas9 Kill Human-Papillomavirus-Induced Cervical Cancer Cells

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1934 ◽  
Author(s):  
Eric Ehrke-Schulz ◽  
Sonja Heinemann ◽  
Lukas Schulte ◽  
Maren Schiwon ◽  
Anja Ehrhardt
Keyword(s):  
Cervical Cancer ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cancer Cell Lines ◽  
Adenoviral Vectors ◽  
Human Papillomaviruses ◽  
Cervical Cancer Cell ◽  
Adenoviral Delivery ◽  
Cervical Cancer Cells

Human papillomaviruses (HPV) cause malignant epithelial cancers including cervical carcinoma, non-melanoma skin and head and neck cancer. They drive tumor development through the expression of their oncoproteins E6 and E7. Designer nucleases were shown to be efficient to specifically destroy HPV16 and HPV18 oncogenes to induce cell cycle arrest and apoptosis. Here, we used high-capacity adenoviral vectors (HCAdVs) expressing the complete CRISPR/Cas9 machinery specific for HPV18-E6 or HPV16-E6. Cervical cancer cell lines SiHa and CaSki containing HPV16 and HeLa cells containing HPV18 genomes integrated into the cellular genome, as well as HPV-negative cancer cells were transduced with HPV-type-specific CRISPR-HCAdV. Upon adenoviral delivery, the expression of HPV-type-specific CRISPR/Cas9 resulted in decreased cell viability of HPV-positive cervical cancer cell lines, whereas HPV-negative cells were unaffected. Transduced cervical cancer cells showed increased apoptosis induction and decreased proliferation compared to untreated or HPV negative control cells. This suggests that HCAdV can serve as HPV-specific cancer gene therapeutic agents when armed with HPV-type-specific CRISPR/Cas9. Based on the versatility of the CRISPR/Cas9 system, we anticipate that our approach can contribute to personalized treatment options specific for the respective HPV type present in each individual tumor.

scholarly journals Upregulation of miR-205 induces CHN1 expression, which is associated with the aggressive behaviour of cervical cancer cells and correlated with lymph node metastasis

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Jianbing Liu ◽  
Yunfeng Li ◽  
Xihua Chen ◽  
Xiangbo Xu ◽  
Haoqi Zhao ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Lymph Node ◽  
High Risk ◽  
Cell Growth ◽  
Lymph Node Metastasis ◽  
Cancer Cells ◽  
Migration And Invasion ◽  
Node Metastasis ◽  
Cervical Cancer Cells ◽  
Human Cervical Cancer

Abstract Background Cervical cancer is the leading cause of cancer-related death in women worldwide. However, the mechanisms mediating the development and progression of cervical cancer are unclear. In this study, we aimed to elucidate the roles of microRNAs and a1-chimaerin (CHN1) protein in cervical cancer progression. Methods The expression of miR-205 and CHN1 protein was investigated by in situ hybridisation and immunohistochemistry. We predicted the target genes of miR-205 using software prediction and dual luciferase assays. The expression of mRNAs and proteins was tested by qRT-PCR and western blotting respectively. The ability of cell growth, migration and invasion was evaluated by CCK-8 and transwell. Cell apoptosis was analysed by flow cytometry analysis. Results We found that miR-205 and CHN1 were highly expressed in human cervical cancer tissue compared with paired normal cervical tissues. The CHN1 gene was shown to be targeted by miR-205 in HeLa cells. Interestingly, transfection with miR-205 mimic upregulated CHN1 mRNA and protein, while miR-205 inhibitor downregulated CHN1 in high-risk and human papilloma virus (HPV)-negative human cervical cancer cells in vitro,. These data suggested that miR-205 positively regulated the expression of CHN1. Furthermore, the miR-205 mimic promoted cell growth, apoptosis, migration, and invasion in high-risk and HPV-negative cervical cancer cells, while the miR-205 inhibitor blocked these biological processes. Knockdown of CHN1 obviously reduced the aggressive cellular behaviours induced by upregulation of miR-205, suggesting that miR-205 positively regulated CHN1 to mediate these cell behaviours during the development of cervical cancer. Furthermore, CHN1 was correlated with lymph node metastasis in clinical specimens. Conclusions Our findings showed that miR-205 positively regulated CHN1 to mediate cell growth, apoptosis, migration, and invasion during cervical cancer development, particularly for high-risk HPV-type cervical cancer. These findings suggested that dysregulation of miR-205 and subsequent abnormalities in CHN1 expression promoted the oncogenic potential of human cervical cancer.

scholarly journals A New E6/P63 Pathway, Together with a Strong E7/E2F Mitotic Pathway, Modulates the Transcriptome in Cervical Cancer Cells

2007 ◽  
Vol 81 (17) ◽  
pp. 9368-9376 ◽  
Author(s):  
Sébastien Teissier ◽  
Youcef Ben Khalifa ◽  
Marcella Mori ◽  
Patricia Pautier ◽  
Christian Desaintes ◽  
...  
Keyword(s):  
Cervical Carcinoma ◽  
Target Genes ◽  
Stage Iv ◽  
Human Papillomaviruses ◽  
Critical Event ◽  
Cdna Sequences ◽  
Cervical Carcinoma Cell Line ◽  
Cervical Cancer Cells ◽  
E6 And E7 ◽  
Interfering Rna

ABSTRACT Cervical carcinoma is associated with certain types of human papillomaviruses expressing the E6 and E7 oncogenes, which are involved in carcinogenesis through their interactions with the p53 and pRB pathways, respectively. A critical event on the path to malignant transformation is often manifested by the loss of expression of the viral E2 transcription factor due to the integration into the host genome of the viral DNA. Using microarrays, we have previously shown that reintroduction of a functional E2 in the HeLa cervical carcinoma cell line activates a cluster of p53 target genes while at the same time severely repressing a group of E2F target genes. In the present study, using new high-density microarrays containing more than 22,000 human cDNA sequences, we identified a novel p63 pathway among E2-activated genes and 38 new mitotic genes repressed by E2. We then sought to determine the pathways through which these genes were modulated and used an approach that relies on small interfering RNA to demonstrate that the p63 target genes were activated through silencing of the E6/E6AP pathway while the mitotic genes were mainly repressed through E7 silencing. Importantly, a subset of the mitotic genes was shown to be significantly induced in biopsies of stage IV cervical cancers, which points to a prominent E7 pathway in cervical carcinoma.

scholarly journals Interferon-β Induced microRNA-129-5p Down-Regulates HPV-18 E6 and E7 Viral Gene Expression by Targeting SP1 in Cervical Cancer Cells

PLoS ONE ◽  
2013 ◽  
Vol 8 (12) ◽  
pp. e81366 ◽  
Author(s):  
Jiarong Zhang ◽  
Shuangdi Li ◽  
Qin Yan ◽  
Xiaoyue Chen ◽  
Yixia Yang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cervical Cancer ◽  
Cancer Cells ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Interferon Β ◽  
Cervical Cancer Cells ◽  
E6 And E7 ◽  
Hpv 18

scholarly journals Endogenous Human Papillomavirus E6 and E7 Proteins Differentially Regulate Proliferation, Senescence, and Apoptosis in HeLa Cervical Carcinoma Cells

2003 ◽  
Vol 77 (2) ◽  
pp. 1551-1563 ◽  
Author(s):  
Rosa Anna DeFilippis ◽  
Edward C. Goodwin ◽  
Lingling Wu ◽  
Daniel DiMaio
Keyword(s):  
Cervical Cancer ◽  
Human Papillomavirus ◽  
Cancer Cells ◽  
Cervical Carcinoma ◽  
Carcinoma Cells ◽  
Rb Pathway ◽  
Cervical Cancer Cells ◽  
E6 And E7 ◽  
E7 Proteins ◽  
E6 Protein

ABSTRACT Cervical cancer cells express high-risk human papillomavirus (HPV) E6 and E7 proteins, and repression of HPV gene expression causes the cells to cease proliferation and undergo senescence. However, it is not known whether both HPV proteins are required to maintain the proliferative state of cervical cancer cells, or whether mutations that accumulate during carcinogenesis eliminate the need for one or the other of them. To address these questions, we used the bovine papillomavirus E2 protein to repress the expression of either the E6 protein or the E7 protein encoded by integrated HPV18 DNA in HeLa cervical carcinoma cells. Repression of the E7 protein activated the Rb pathway but not the p53 pathway and triggered senescence, whereas repression of the E6 protein activated the p53 pathway but not the Rb pathway and triggered both senescence and apoptosis. Telomerase activity, cyclin-dependent kinase activity, and expression of c-myc were markedly inhibited by repression of either E6 or E7. These results demonstrate that continuous expression of both the E6 and the E7 protein is required for optimal proliferation of cervical carcinoma cells and that the two viral proteins exert distinct effects on cell survival and proliferation. Therefore, strategies that inhibit the expression or activity of either viral protein are likely to inhibit the growth of HPV-associated cancers.

Wogonin induces apoptosis by suppressing E6 and E7 expressions and activating intrinsic signaling pathways in HPV-16 cervical cancer cells

2013 ◽  
Vol 29 (4) ◽  
pp. 259-272 ◽  
Author(s):  
Man Sub Kim ◽  
Yesol Bak ◽  
Yun Sun Park ◽  
Dong Hun Lee ◽  
Jung Hee Kim ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Cancer Cells ◽  
Signaling Pathways ◽  
Hpv 16 ◽  
Cervical Cancer Cells ◽  
E6 And E7
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