Genetic Epidemiology

这个遗传流行病学项目的许多调查都来自于对癌症高风险家庭的观察或其他病因学研究。来自意大利东北部183例黑色素瘤病例和179例对照病例的问卷数据、肿瘤和DNA被用于评估黑色素瘤中参与map -激酶信号转导通路的黑色素皮质素-1受体（MC1R）基因和BRAF癌基因的体细胞突变。MC1R是人类色素沉积的主要调节因子。在身体暴露在阳光下的区域和有限的慢性太阳损伤的黑色素瘤患者中，我们发现MC1R种系变异与BRAF癌基因体细胞突变的黑色素瘤之间存在很强的相关性。我们计划首先在独立人群中验证这种关联和潜在修饰剂的作用。生殖系CDKN2A突变已在20-40%的高危黑色素瘤易发家族中被观察到，但其在基于人群的病例和对照组中的患病率知之甚少。多种MC1R变异与黑色素瘤的风险增加有关。冰岛人口中红发和金发受试者的频率很高，使其成为评估MC1R变异的理想人群。我们对来自冰岛的703例登记确定的黑色素瘤病例和691例基于人群的对照进行了CDKN2A和MC1R基因重测序，冰岛是黑色素瘤发病率迅速上升的国家。对协会的评价正在进行中。导致黑色素瘤发展的潜在途径之一包括失去对普通黑色素细胞痣的调节，这些黑色素细胞痣获得非典型或发育不良的特征，可以进一步发展为肿瘤。为了研究这一途径，我们目前正在收集来自意大利东北部同一受试者的正常皮肤、普通黑素细胞痣、发育不良痣、黑色素瘤和黑色素瘤转移灶的多个组织样本。当样本量达到100名受试者时，我们计划在系列组织样本和种系DNA中研究细胞周期、端粒、转导通路等多个基因突变的表达和存在，探讨黑色素瘤通过痣发展的机制。对来自DCEG成人脑肿瘤病例对照研究的365例胶质瘤患者的亲属进行了个人/家族病史和其他危险因素的访谈。与人口控制相比，对一级亲属癌症风险的分析已经完成。一项儿童髓母细胞瘤的回顾性单机构研究的问卷调查数据显示，几乎没有证据表明髓母细胞瘤患者的亲属患癌症的风险增加。脊索瘤是一种罕见的原发性恶性骨肿瘤，主要发生在胚胎脊索干细胞未能正常退化的轴骨中。我们发起了一项与波士顿麻省总医院放射肿瘤科的合作，试图识别脊索瘤家族，以帮助绘制和识别脊索瘤易感基因。该项目包括从最可能有脊索瘤遗传易感性的患者亚组（即诊断为脊索瘤<18岁的患者）获取个人和家族病史、颊细胞和肿瘤组织切片。在过去的一年中，我们完成了45例脊索瘤患者的登记。我们正在获取他们的个人和家族病史、口腔细胞和肿瘤组织。通过与耶鲁大学组织微阵列（TMA）核心设备的合作，我们成功构建了842例来自波兰乳腺癌研究的侵袭性肿瘤（TMA1）的TMA。我们用免疫组织化学方法对这些tma进行了18个涉及激素生物合成、代谢和受体介导途径的分子标记的染色。对这些标志物的分析表明，乳腺癌的危险因素可能因分子亚型和以激素标志物共同表达为特征的激素途径而异。我们还使用新开发的自动定量分析（AQUA）对这些阵列进行了四种标记（er - α, er - β， PR和HER2）的染色。两种方法（AQUA和IHC）对相同四种标记物的比较表明，对tma中代表的肿瘤进行AQUA分析提供了可靠的、定量的标记物表达测量。最近，我们建立了一套新的tma (TMA2)，包括919例波兰乳腺癌病例，具有三倍冗余。TMA1和TMA2加起来有1500个侵袭性肿瘤，至少有双重冗余。我们使用AQUA对所有5种分子标记标记的新阵列（TMA2）和CK5和EGFR的旧阵列（TMA1）进行了染色，这为我们提供了基于tma的完整侵袭性乳腺癌病例的所有5种标记标记的AQUA数据。我们还建立了一种从非侵入性上皮组织（正常末端导管小叶单位[TDLUs]和导管原位癌[DCIS]）构建TMA的技术，并成功构建了32个TMA块，共1,547个组织核，包括560例波兰乳腺癌的非侵入性（正常TDLUs [N=689]和DCIS [N=501]）组织及其相关的浸润性肿瘤（N=357）。我们已经用所有五种分子标记对这些非侵入性阵列进行了染色，分析正在进行中。肾细胞癌（RCC）的发病率在中欧和东欧是世界上最高的。von Hippel - lindo - hypoxia Inducible Factor （VHL-HIF）通路与肾癌的发生有关。我们研究了VHLHIF通路中常见基因变异在散发性RCC和透明细胞RCC易感性中的作用。我们确定了与肾癌风险相关的VHL-HIF通路中基因的常见遗传变异。我们计划在更多的研究人群中重复这一发现。对瑞典和丹麦登记数据的分析仍在继续。我们对CLL和多发性骨髓瘤（MM）相关的医疗条件进行了分析，发现呼吸道感染和CLL和MM的风险增加，表明它们可能在易感个体中引发恶性过程。我们还证明，癌症家族史增加了淋巴瘤患者发展某些第二种癌症的风险。我们正在进行一项新的研究，使用来自瑞典的实验室和人口登记数据来量化不确定意义单克隆γ病（MGUS）与其他LP肿瘤的个人和家族关联。在瑞典所有主要血液学单位中发现了大约4500例有血缘关系的MGUS病例。与对照组相比，MGUS患者亲属的相对危险度（RR）显著升高。MM、WM和CLL的风险也增加。父母、兄弟姐妹和后代的风险估计相似；当我们根据病例的年龄（65岁以上与65岁以下）和亲属的性别来估计风险时，情况也是如此。在MGUS病例的亲属中，NHL或HL的风险没有增加。对WM病例亲属的初步分析显示，他们患MGUS、WM和CLL的风险较高，但不患MM。这支持了我们来自高风险家庭的数据，即某些MGUS亚型、WM和CLL之间存在遗传关联。我们也开始使用类似的方法分析骨髓增生性（MPD）恶性肿瘤，包括真性红细胞增多症（PV）、原发性血小板增多症（ET）和骨髓纤维化（MF）。初步结果表明，MPD患者的一级亲属发生任何MPD的相对风险都很高（RR=5.6, 95% CI, 3.8-8.2）。

Many of the investigations in this genetic epidemiology project arise from observations in families at high risk of cancer or in other etiologic studies. Questionnaire data, tumor, and DNA from a case-control study of 183 incident melanoma cases and 179 controls conducted in North-Eastern Italy were used to evaluate the melanocortin-1 receptor (MC1R) gene, the major regulator of pigmentation in humans, and somatic mutations of the BRAF oncogene, involved in the MAP-kinase pathway of signal transduction in melanomas. In subjects with melanoma arising on sun exposed areas of the body and with limited chronic solar damage, we found a strong association between MC1R germline variants and melanoma with somatic mutations in the BRAF oncogene. We plan to first verify this association and the role of potential modifiers in an independent population. Germline CDKN2A mutations have been observed in 20-40% of high-risk melanoma-prone families, however little is known about their prevalence in population-based cases and controls. Multiple MC1R variants have been associated with increased risk of melanoma. The Icelandic population has a high frequency of red hair and blond hair color subjects making it an ideal population to evaluate variation in MC1R.We resequenced the CDKN2A and MC1R genes in 703 registry-ascertained melanoma cases and 691 population-based controls from Iceland, a country in which the incidence of melanoma has increased rapidly. Evaluation of associations is in progress.One of the potential pathways that leads to the development of melanoma includes the loss of regulation of common melanocytic nevi, which acquire atypic or dysplastic characteristics that can further evolve in neoplasia. To study this pathway, we are currently collecting multiple tissue samples of normal skin, common melanocytic nevi, dysplastic nevi, melanoma and metastasis from melanoma from the same subjects from North-Eastern Italy. When the sample size reaches 100 subjects, we plan to study the expression and presence of mutations in multiple genes of the cell cycle, telomere, and transduction pathways in the serial tissue samples and germline DNA to explore the mechanisms involved in melanoma development through nevi.Relatives of 365 of the glioma cases from a DCEG comprehensive case-control study of adults with brain tumors were interviewed about personal/family medical history and other risk factors. Analyses to examine the risk of cancer among the first degree relatives compared to population controls have been completed. Examination of questionnaire data from a retrospective single institution study of childhood medulloblastoma showed little evidence for increased cancer risks among relatives of medulloblastoma patients.Chordoma is a rare primary malignant bone tumor that arises mainly in the axial skeleton from rests of embryonic notochordal stem cells that failed to undergo normal regression. We initiated a collaboration with the Department of Radiation Oncology, Massachusetts General Hospital, Boston, to try to identify chordoma families to help map and identify a chordoma susceptibility gene. The project involves obtaining personal and family medical history, buccal cells and slides of tumor tissue from the subgroup of patients most likely to have a genetic predisposition to chordoma: those diagnosed with chordoma <18 years. During the past year we completed enrollment of 45 chordoma patients. We are in the process of obtaining personal and family medical history, buccal cells and tumor tissue from them.In collaboration with Yale University Tissue Microarray (TMA) core facility, we have successfully built TMAs of 842 invasive tumors (TMA1) collected from the Polish Breast Cancer Study. We have immunohistochemically stained these TMAs for 18 molecular markers involved in hormone biosynthesis, metabolism, and receptor mediated pathways. Analyses of these markers suggest that risk factors for breast cancer may vary by molecular subtypes and by hormone pathways characterized by co-expression of the hormonal markers. We have also stained these arrays for four markers (ER-alpha, ER-beta, PR and HER2) using a newly developed Automated Quantitative Analysis (AQUA). Comparison of the two approaches (AQUA and IHC) for the same four markers demonstrated AQUA analyses of tumors represented in TMAs provide reliable, quantitative measures of marker expression. Recently, we built a new set of TMAs (TMA2) including 919 Polish breast cancer cases with three-fold redundancy. Combined, TMA1 and TMA2, have 1,500 invasive tumors with at least two-fold redundancy. We have stained the new arrays (TMA2) for all five molecular signature markers and the old arrays (TMA1) for CK5 and EGFR using AQUA, which gave us AQUA data for all five signature markers from a complete set of invasive breast cancer cases built on TMAs. We have also established a technique in constructing TMAs from non-invasive epithelial tissues (normal terminal duct lobular units [TDLUs] and ductal carcinoma in situ [DCIS]), and successfully built 32 TMA blocks of 1,547 tissue cores including both non-invasive (normal TDLUs [N=689] and DCIS [N=501]) tissues and their associated invasive tumors (N=357) collected from 560 Polish breast cancer cases. We have stained these non-invasive arrays with all five molecular signature markers and analysis is in process. Renal cell carcinoma (RCC) rates in Central and Eastern Europe are among the highest in the world. The von Hippel Lindau-Hypoxia Inducible Factor (VHL-HIF) pathway has been implicated in kidney cancer tumorigenesis. We investigated the role of common variants in genes in the VHLHIF pathway in the susceptibility of sporadic RCC and clear cell RCC. We identified common genetic variants in genes in the VHL-HIF pathway associated with kidney cancer risk. We plan to replicate the finding in additional study populations. Analyses of registry data from Sweden and Denmark are continuing. We conducted analyses of medical conditions associated with CLL and multiple myeloma (MM) and showed an increased risk for respiratory infections and both CLL and MM, suggesting that they may trigger a malignant process in susceptible individuals. We also demonstrated that family history of cancer increased risk of individuals with lymphoma to develop certain second cancers. We are conducting a new study using laboratory and population registry data from Sweden to quantify personal and familial associations of monoclonal gammopathy of uncertain significance (MGUS) with other LP tumors. Approximately 4500 MGUS cases were identified from all of the major hematologyoncology units in Sweden who had linkable relatives. Compared with controls, relative risk (RR) of MGUS was significantly increased in relatives of MGUS cases. Risks of MM, WM, and CLL were also increased. Risk-estimates were similar for parents, siblings, and offspring; the same was true when we estimated risks by age at MGUS of cases (above vs. below 65 yrs), and sex of relatives. There was no increased risk of NHL or HL among relatives of MGUS cases. Preliminary analyses of relatives of WM cases showed that they had a higher risk of MGUS, WM, and CLL but not MM. This supports our data from high risk families indicating a genetic association between certain MGUS subtypes, WM, and CLL. We have also begun to analyze myeloproliferative (MPD) malignancies including polycythemia vera (PV), essential thrombocythemia (ET) and myelofibrosis (MF) using similar methodology. Preliminary results indicate that the relative risks for developing any MPD in first degree relatives of MPD patients are highly elevated (RR=5.6, 95% CI, 3.8-8.2).