Mechanism of Folate Deficiency as a Co-Factor for HPV16-induced Carcinogenesis

叶酸缺乏作为 HPV16 诱发癌变的辅助因素的机制

• 批准号: 8624526
• 负责人: Asok Antony
• 金额: --
• 依托单位: RLR VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8624526
• 关键词: Affinity; Applications Grants; Benign; Binding; Capsid; Capsid Proteins; Cells; Clone Cells; DNA; DNA Fragmentation; DNA Integration; DNA Maintenance; Dependovirus; Developing Countries; Diet; Dose; Elderly; Ensure; Exposure to; Folate; Folic Acid Deficiency; Frequencies; Gene Expression; Generations; Genes; Genome; Genomic DNA; Genomics; HIV; HPV-High Risk; Health; Healthcare; Heterogeneous-Nuclear Ribonucleoproteins; Human Papillomavirus; Human papillomavirus 16; Immunodeficient Mouse; Implant; In Vitro; Individual; Infection; Investigation; L2 viral capsid protein; Lead; Leucovorin; Malignant Neoplasms; Measures; Methotrexate; Minor; Modeling; Molecular; Mus; Normal Cell; Oncogenes; Operon; Papillomavirus; Patients; Physiological; Positioning Attribute; RNA; RNA-Protein Interaction; Risk; Series; Staging; Testing; Time; Tissues; Transcript; Uracil; Veterans; Viral; Viral Load result; Vitamin B 12 Deficiency; carcinogenesis; ds-DNA; feeding; implantation; in vivo; keratinocyte; monolayer; mutant; novel; nutrition; permissiveness; prevent; subcutaneous

DESCRIPTION (provided by applicant): We have recently identified that homocysteinylation of heterogeneous nuclear ribonucleoprotein-E1 (hnRNP-E1) during physiological folate deficiency, activates a nutrition-sensitive posttranscriptional RNA operon that also includes an important interaction with two loci in Human Papillomavirus type-16 (HPV16) RNA. This HPV16 RNA-protein interaction with homocysteinylated-hnRNP-E1 led to a profound perturbation in the generation of both HPV16 major (L1) and minor (L2) viral capsid proteins in vitro; in HPV16-harboring keratinocytes that were propagated as monolayers; as well as when these HPV16-keratinocytes were developed into organotypic rafts in physiologic low-folate medium. Despite a similar HPV16 DNA viral load in HPV16-high folate- and low folate-organotypic rafts, the latter contained a high-level of integration of HPV16 DNA into genomic DNA. Subcutaneous implantation of 18-day HPV16-low folate-organotypic rafts in Beige Nude XID immunodeficient mice led to an aggressive HPV16-induced cancer within 12 weeks. Thus, we have developed a new model of HPV16-induced carcinogenesis within a time frame of less than 4 months. Because folate deficiency can induce single-strand nicks in genomic DNA and also double-strand DNA fragmentation, our overarching hypothesis is that the unstable genomic DNA in HPV16-low folate-organotypic rafts is primarily responsible for the high-level integration of HPV16 DNA into genomic DNA and transformation of this benign tissue to cancer. So we will test various aspects of this hypothesis using three specific aims: In Specific Aim #1, we will characterize the time-course relationship, extent, and consequence of integration of HPV16 DNA into the genomic DNA of HPV16-organotypic rafts in vitro and in vivo, and assess the frequency of transformation of benign HPV16-organotypic rafts into cancer in immunodeficient mice. In Specific Aim #2 we will assess the potential of amplified 'capsid-less' HPV16 DNA to integrate into unperturbed and intact [stable] genomic DNA after transduction and expression of novel genes encoding various strengths of molecular mimics of homocysteinylated-hnRNP-E1 into HPV16-harboring keratinocytes that are subsequently developed into organotypic rafts under high-folate conditions. In Specific Aim #3, we will assess the permissiveness of unperturbed and transiently perturbed genomic DNA to integrate HPV16 DNA in AAV2-transduced [high folate] HPV16-organotypic rafts that either do or do not contain an abundance of 'capsid-less' HPV16 DNA, and then evaluate the potential for such genomic HPV16 DNA integration to induce carcinogenesis within implants of rafts in Beige Nude XID mice. Such investigations will ultimately provide a better understanding of the mechanism of transformation of HPV16-infected tissues to cancer and benefit HPV-infected elderly Veterans with poor nutrition; Veterans with HPV16 and human immunodeficiency virus (HIV); and those in developing countries where the combination of poor nutrition, and co-infection with HIV and HPV16 places individuals at high risk for HPV-induced cancers

描述（由申请人提供）：