HPV INTEGRATION AS A BIOMARKER FOR CIN BEHAVIOR

HPV 整合作为 CIN 行为的生物标志物

• 批准号: 6607280
• 负责人: WAYNE D LANCASTER
• 金额: $ 7.45万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-03 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6607280
• 关键词: DNA primers; biomarker; cervix neoplasms; clinical research; genetic transcription; human papillomavirus; human subject; male reproductive system neoplasm; neoplasm /cancer nutrition therapy; neoplastic growth; oncoproteins; patient oriented research; polymerase chain reaction; retinoate; squamous cell carcinoma; viral carcinogenesis; virus DNA; virus genetics; virus integration; virus protein; virus related neoplasm /cancer

DESCRIPTION (provided by applicant)Human papillomavirus (HPV) infection of the cervix can result in squamous intraepithelial neoplasia that can progress through increasing less differentiated stages that can give rise to squamous cell cancer of the cervix. The vast majority of cervix cancers are associated with high risk HPV types. Cancer is thought to result from inactivation of p53 by HPV E6 and pRB by HPV E7 proteins. p53 is the guardian of the genome and protects against DNA damage and pRB is a major G1 check point in the cell cycle. Abrogation of these activities by high risk HPV oncoproteins can result in the accumulation of mutations and eventually cancer. Early events in the progression of squamous intraepithelial lesions (SIL) to cancer are not well understood. However, it has been postulated that a change in the physical state of the viral genome (episomal to integrated form) may precipitate cancer development. Testing this hypothesis in a prospective manner cannot be done. However, the response of high grade premalignant SIL to topical chemotherapeutic agents or placebo may provide insights into the relationship between state of the viral genome and clinical response. Approximately 150 patients with high grade SIL were randomized to placebo or topical all trans retinoic acid (atRA). The subjects were biopsied at baseline and week 12 (end of study) to determine clinical disease. Subjects treated with topical atRA for four days were significantly more likely to revert to normal or non-treatable disease state than subjects getting placebo (p=0.05). We hypothesize that SIL in a high proportion of patients that failed to respond to atRA contain transcripts derived from integrated HPV. These transcripts are more stable than those derived from episomal virus DNA and the level of viral oneoproteins is higher in cells with integrated sequences. atRA may not be able to decrease the levels of oncoproteins sufficiently low to induce lesion resolution in those lesions containing integrated HPV DNA. We will determine the ratios of 5' (E7) and 3' (E5) sequences in reversed transcribed RNA obtained from formalin-fixed biopsies taken at baseline and week 12. If the ratio of E7:E5 approximates 1 then sequences are episomal; E7:E5 >1 then E5 sequences are underrepresented due to integration of virus DNA. Demonstration that atRA-resistant SIL contain transcripts derived from integrated HPV DNA would provide a powerful biomarker to identify those women who would likely fail nonablative therapy and who would be at increased risk of progression to cervical cancer.

描述（由申请人提供）子宫颈的人乳头瘤病毒（HPV）感染可导致鳞状上皮内瘤变，该瘤变可通过增加分化程度较低的阶段进展，从而可引起子宫颈鳞状细胞癌。绝大多数宫颈癌与高危 HPV 类型有关。癌症被认为是由于 HPV E6 蛋白使 p53 失活和 HPV E7 蛋白使 pRB 失活所致。 p53 是基因组的守护者，可防止 DNA 损伤，而 pRB 是细胞周期中主要的 G1 检查点。高危 HPV 癌蛋白消除这些活性可能导致突变积累，最终导致癌症。鳞状上皮内病变 (SIL) 进展为癌症的早期事件尚不清楚。然而，据推测，病毒基因组物理状态的变化（游离形式到整合形式）可能会促进癌症的发展。无法以前瞻性方式检验这一假设。然而，高级别癌前 SIL 对局部化疗药物或安慰剂的反应可能有助于了解病毒基因组状态与临床反应之间的关系。大约 150 名患有重度 SIL 的患者被随机分配到安慰剂组或局部全反式维甲酸 (atRA) 组。在基线和第 12 周（研究结束）对受试者进行活检以确定临床疾病。与接受安慰剂的受试者相比，接受局部 atRA 治疗四天的受试者明显更有可能恢复正常或不可治疗的疾病状态 (p=0.05)。我们假设对 atRA 没有反应的大部分患者中的 SIL 含有源自整合 HPV 的转录物。这些转录本比源自附加型病毒 DNA 的转录本更稳定，并且具有整合序列的细胞中病毒蛋白的水平更高。 atRA 可能无法将癌蛋白水平降低到足够低的水平，从而在含有整合 HPV DNA 的病变中诱导病变消退。我们将确定从基线和第 12 周进行的福尔马林固定活检获得的逆转录 RNA 中 5' (E7) 和 3' (E5) 序列的比率。如果 E7:E5 的比率接近 1，则序列是附加型的；如果 E7:E5 的比率接近 1，则序列是附加型的；如果 E7:E5 的比率接近 1，则序列是附加型的； E7:E5 >1 则 E5 序列由于病毒 DNA 的整合而代表性不足。证明 atRA 抗性 SIL 含有源自整合 HPV DNA 的转录物，这将提供一个强大的生物标志物，用于识别那些可能会失败非消融治疗以及进展为宫颈癌风险增加的女性。