Mitochondrial DNA Mutations in Pancreatic Cancer

描述（由申请人提供）：胰腺癌是美国癌症相关死亡的第四大原因，但强大的遗传和环境风险因素仍然难以捉摸。为了有效地预防和治疗这种恶性肿瘤，鉴定易患胰腺癌的遗传多态性以及确定这些多态性如何改变其他危险因素与癌症之间的关系至关重要。此外，从循环生物体液中鉴定出的疾病特异性遗传畸变的发现将促进胰腺癌早期检测诊断工具的发展。虽然大多数遗传关联研究都只关注核基因多态性作为癌症发病的易感性因素或体细胞改变作为癌症进展的指标，但线粒体DNA （mtDNA）变异作为胰腺癌的危险因素尚未得到研究。该项目将在旧金山湾区进行一项大型基于人群的病例对照研究，评估mtDNA序列变异与胰腺癌之间的关系（309例病例和618例匹配对照）。通过使用最近开发的Affymetrix线粒体重测序阵列2.0 (MitoChip)，我们将对整个mtDNA基因组（~16.5kb）进行与胰腺癌相关的全面分析。MitoChip能够检测种系和获得性突变，并已被证明可以检测多种组织（包括血液）中的mtDNA突变。这将是迄今为止对完整mtDNA基因组序列和胰腺癌进行的最大的基于人群的评估，并有可能确定易患这种恶性肿瘤的人群的多态性。此外，如果我们确定在胰腺癌患者的血液中检测到独特的mtDNA异质突变；这些可能作为胰腺癌早期检测的有力生物标志物。公共卫生相关性：该项目将在旧金山湾区进行一项基于人群的大型病例对照研究，评估线粒体DNA （mtDNA）序列变异与胰腺癌之间的关系。通过使用最近开发的Affymetrix线粒体重测序阵列2.0 (MitoChip)，我们将对整个mtDNA基因组（~16.5kb）进行与胰腺癌相关的全面分析。这将是迄今为止对完整mtDNA基因组序列和胰腺癌进行的最大的基于人群的评估，并有可能确定易患这种恶性肿瘤的人群的多态性。此外，如果我们确定在胰腺癌患者的血液中检测到独特的mtDNA异质突变；这些可能作为胰腺癌早期检测的有力生物标志物。

DESCRIPTION (provided by applicant): Pancreatic cancer is the fourth leading cause of cancer-related deaths in the United States, yet strong genetic and environmental risk factors remain elusive. In order to effectively prevent and treat this malignancy it is critical to identify genetic polymorphisms that predispose subsets of the population to pancreatic cancer and determine how these polymorphisms modify the relationship between other risk factors and cancer. Additionally, the discovery of disease-specific genetic aberrations identified from circulating biofluids would advance the development of diagnostic tools for the early detection of pancreatic cancer. While the majority of genetic association studies have focused either exclusively on nuclear gene polymorphisms as susceptibility factors for cancer onset or on somatic alterations as indicators of cancer progression, mitochondrial DNA (mtDNA) variation has not been investigated as a risk factor for pancreatic cancer. This project will assess the association between mtDNA sequence variants and pancreatic cancer in a large population-based case-control study in the San Francisco Bay Area (309 cases and 618 matched controls). By using the recently developed the Affymetrix Mitochondrial Resequencing Array 2.0 (MitoChip) we will be performing a comprehensive analysis of the entire mtDNA genome (~16.5kb) for associations with pancreatic cancer. The MitoChip enables the detection of both germline and acquired mutations and has been shown detect mtDNA mutations in multiple tissues (including blood). This would be the largest population-based assessment of the complete mtDNA genomic sequence and pancreatic cancer to date and has the potential to identify polymorphisms that predispose subsets of the population to this malignancy. In addition, if we determine that unique mtDNA heteroplasmic mutations are detectable in the blood of pancreatic cancer cases; these may potentially serve as powerful biomarkers for the early detection of pancreatic cancer. PUBLIC HEALTH RELEVANCE: This project will assess the association between mitochondrial DNA (mtDNA) sequence variants and pancreatic cancer in a large population-based case-control study in the San Francisco Bay Area. By using the recently developed the Affymetrix Mitochondrial Resequencing Array 2.0 (MitoChip) we will be performing a comprehensive analysis of the entire mtDNA genome (~16.5kb) for associations with pancreatic cancer. This would be the largest population-based assessment of the complete mtDNA genomic sequence and pancreatic cancer to date and has the potential to identify polymorphisms that predispose subsets of the population to this malignancy. In addition, if we determine that unique mtDNA heteroplasmic mutations are detectable in the blood of pancreatic cancer cases; these may potentially serve as powerful biomarkers for the early detection of pancreatic cancer.