Epigenetic role of GRHL2 in HPV-associated oral cancer

GRHL2 在 HPV 相关口腔癌中的表观遗传作用

• 批准号: 8889761
• 负责人: Mo K. Kang
• 金额: $ 28.4万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-24 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8889761
• 关键词: Alcohol consumption; Apoptotic; Benzo(a)pyrene; Biological Markers; Biological Process; Boxing; Cell Fraction; Cells; Chronic; Code; Complex; DNA Methylation; Data; Development; Epigenetic Process; Epithelial; Epithelial Cells; Exposure to; Functional RNA; Gene Targeting; Genes; Genetic; Goals; HPV-High Risk; Health; High-Throughput Nucleotide Sequencing; Histones; Human; Human Papillomavirus; Human papilloma virus infection; Human papillomavirus 16; In Vitro; Incidence; Infection; Laboratories; Lead; Maintenance; Malignant Epithelial Cell; Malignant Neoplasms; Mediating; Methylation; MicroRNAs; Modeling; Modification; Oncogenes; Oncogenic; Oral; Oral health; Outcome; Patients; Phenotype; Proteins; Publishing; Regulation; Research; Risk Factors; Role; Smoking History; Solid Neoplasm; Tail; Testing; Tumor Cell Line; Tumorigenicity; Viral Oncogene; Virion; cancer stem cell; chromatin immunoprecipitation; effective therapy; epigenome; epigenomics; histone modification; human TERT protein; immortalized cell; in vivo; keratinocyte; keratinocyte differentiation; knock-down; loss of function; malignant mouth neoplasm; mouth squamous cell carcinoma; novel; novel diagnostics; oral carcinogenesis; oral cavity epithelium; pluripotency; promoter; research study; response; self-renewal; stem; stem cell division; therapeutic target; tumor

DESCRIPTION (provided by applicant): Long-term goal of our research is to discover novel biomarkers and effective therapies against oral cancer. The current project will investigate the role of Grainyhead-like 2 (GRHL2) in mediating oral carcinogenesis by "high risk" human papillomavirus (HPV) through epigenetic mechanisms. GRHL2 regulates keratinocyte cell fate through multiple target genes, including human telomerase reverse transcriptase (hTERT) gene, forkhead box protein 1 (FoxM1), and epidermal differentiation complex (EDC) genes. Our recent published data revealed that GRHL2 is a master regulator of keratinocyte proliferation and differentiation. GRHL2 elicits these effects through epigenetic mechanisms that involve altered DNA methylation and histone modifications at target gene promoters. We found that GRHL2 is notably induced in human oral keratinocytes (HOKs) harboring "high risk" HPV and HPV+ oral squamous cell carcinomas (OSCCs). Furthermore, high level of GRHL2 was detected in OSCC tumor spheroids, which are enriched with cancer stem cells (CSCs). When GRHL2 was knocked down in OSCCs, self-renewal of tumor spheroids in vitro and tumorigenicity in vivo were significantly impaired. Thus, HPV may cause deregulation of GRHL2 to promote its oncogenic activity by inducing the FoxM1 oncogene and enhance CSC self-renewal. Recent studies underscore the importance of non-coding RNAs in regulation of pluripotency and CSC self-renewal. GRHL2 upregulates miR-21, an "oncomir" associated with HPV and CSC phenotype. Thus, differential regulation of non-coding RNAs by GRHL2 may underlie the mechanism of enhancing CSC phenotype in OSCCs. To investigate the pathobiology of HPV in oral carcinogenesis, we have constructed infectious HPV16 virions capable of expressing the viral oncogenes. These novel HPV virions will allow us to test the effects of HPV infection in primary NHOK in well-controlled experiments. In the current project, we will test the hypothesis that GRHL2 is necessary for HPV-associated cellular aberrations by altered epigenetic regulation of its target genes and by enhancing CSC self-renewal, resulting in the maintenance of oral cancer phenotype. This novel hypothesis will be tested by investigating the pathophysiologic role of GRHL2 in HPV-associated cellular aberrations; determining the epigenetic mechanisms by which GRHL2 modulates epithelial proliferation and differentiation, and how GRHL2-associated epigenomic profile is altered by HPV; and investigating whether GRHL2 determines CSC phenotype in HPV-associated oral cancer by regulation of non-coding RNAs. This project will delineate the epigenetic mechanisms by which GRHL2 mediates pathobiology of "high risk" HPV in oral carcinogenesis, and will validate the role of GRHL2 in CSC renewal through regulation of non-coding RNAs, which may be used for discovery of novel diagnostic marker and therapeutic targets.

描述（由申请人提供）：我们研究的长期目标是发现新型的生物标志物和针对口腔癌的有效疗法。当前的项目将通过表观遗传机制来研究通过“高风险”人乳头瘤病毒（HPV）来研究粒状头样2（GRHL2）在介导口服癌变中的作用。 GRHL2通过多个靶基因调节角质形成细胞的命运，包括人端粒酶逆转录酶（HTERT）基因，Forkhead Box蛋白1（FOXM1）和表皮分化复合物（EDC）基因。我们最近发表的数据表明，GRHL2是角质形成细胞增殖和分化的主要调节剂。 GRHL2通过表观遗传机制引起这些作用，这些机制涉及靶基因启动子的DNA甲基化和组蛋白修饰。我们发现，GRHL2在人类口服角质形成细胞（HOKS）中特别诱导，其具有“高风险” HPV和HPV+口服鳞状细胞癌（OSCCS）。此外，在OSCC肿瘤球体中检测到高水平的GRHL2，这些球体富含癌症干细胞（CSC）。当OSCC中击倒GRHL2时，体外肿瘤球体的自我更新显着受损。因此，HPV可能会导致GRHL2的放松管制，从而通过诱导FOXM1癌基因并增强CSC自我更新来促进其致癌活性。最近的研究强调了非编码RNA在调节多能性和CSC自我更新中的重要性。 GRHL2上调了MiR-21，这是一种与HPV和CSC表型相关的“ oncomir”。因此，GRHL2对非编码RNA的差异调节可能是增强OSCC中CSC表型的机制。为了研究口服癌变中HPV的病理生物学，我们已经构建了能够表达病毒癌基因的感染性HPV16病毒体。这些新型的HPV病毒体将使我们能够测试良好控制实验中原发性NHOK中HPV感染的影响。 在当前的项目中，我们将通过改变其靶基因的表观遗传调节并增强CSC自我更新，从而维持口腔癌表型，这是通过改变其靶基因的表观遗传调节而对HPV相关的细胞像差所必需的假设。这一新的假设将通过研究GRHL2在与HPV相关的细胞畸变中的病理生理作用来检验。确定GRHL2调节上皮增殖和分化的表观遗传机制，以及HPV如何改变了与GRHL2相关的表观基因组谱。并研究GRHL2是否通过调节非编码RNA来确定与HPV相关的口腔癌中的CSC表型。该项目将描述GRHL2在口服癌发生中介导“高风险” HPV病原体的表观遗传机制，并将通过调节非编码RNA的调节来验证GRHL2在CSC续订中的作用，这些RNA可用于发现新型诊断标记和治疗目标。