DNA Repair in Human Cancer-Prone Genetic Diseases

人类易患癌症的遗传疾病中的 DNA 修复

基本信息

批准号：
8937627
负责人：
KENNETH H KRAEMER
金额：
$ 147.93万
依托单位：
DIVISION OF BASIC SCIENCES - NCI
依托单位国家：
美国
项目类别：
财政年份：
资助国家：
美国
起止时间：
至
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/8937627
关键词：
12 year old 20 year old 22q Adult Affect Aminoglycosides Autopsy B-Lymphocytes BRAF gene Biological Assay CDKN2A gene Cataract Cell Line Cells Cessation of life Child Chromosomes Clinical Cockayne Syndrome Collaborations Collection Communities DNA DNA Damage DNA Repair DNA Repair Gene Defect Development Developmental Gene Disease Dominant-Negative Mutation ERCC1 gene ERCC3 gene Enrollment Epidemiologist Equilibrium Eye Eye Abnormalities Family Family member Fetal Development Frequencies Functional disorder General Population Genes Goals Gynecologist Hereditary Disease Heterogeneity Heterozygote Histologic Human Human Development Hypersensitivity Individual Infant International Investigation Laboratories Lead Malignant Neoplasms Messenger RNA Methods Molecular Mothers Mutation Natural History Necrosis, Aseptic, of Femur Head Neurologic Nevi and Melanomas Nonsense Codon Nucleotide Excision Repair Operative Surgical Procedures Ophthalmologist PTEN gene Pathway interactions Patients Point Mutation Polymerase Postoperative Period Pregnancy Pregnancy Complications Process Proteins Protocols documentation Publishing RNA Splicing Rare Diseases Reporting Research Personnel Risk Role Series Site Skin Carcinoma Sun Exposure System Testing Toxic effect Trichothiodystrophy Tumor Suppressor Genes Ultraviolet Rays United States National Institutes of Health Walking XPA gene Xeroderma Pigmentosum boys brain size cancer prevention cancer risk cell bank cohort comparative genomic hybridization deafness exome sequencing fetal follow-up hearing impairment human FRAP1 protein improved infancy insight melanoma offspring pre-clinical radiologist

项目摘要

1. XERODERMA PIGMENTOSUM We have been examining XP patients at NIH since 1971. We performed long term follow-up studies of cancer, of hearing loss and of eye abnormalities in XP patients. We found that the XP patients under age 20 years had a 10,000-fold increased risk of non-melanoma skin cancer (NMSK) and a 2000-fold increased risk of melanoma. In our natural history protocol we ascertained and intensively examined 87 XP or Cockayne Syndrome (CS) patients and 55 TTD or XP/TTD patients at NIH and are collaborating with international researchers to study additional patients. We published detailed autopsy reports of 4 XP patients - including the first autopsy of an XP-D patient. The XP-A and XP-D patients were adults with severe neurological degeneration and were found to have infant sized brains. We have now identified mutations in all of the 9 currently known DNA nucleotide excision repair (NER) genes (XPA, XPB, XPC, XPD, XPE, XPF, XPG, ERCC1 and TTDA), in the error-prone polymerase, pol eta and in TTDN1 in nearly 200 XP or TTD patients. We have established several hundred carefully documented cell lines and contributed them to cell banks for use of the general scientific community. We are using array comparative genome hybridization (aCGH) and whole exome sequencing to look for mutations in other genes in cells from XP and TTD patients who do not have mutations in these genes. Our laboratory is the major center in the US for basic, clinical and translational expertise concerning DNA repair related disorders. We are actively seeking and have developed the expertise to recognize unusual patients who have unique disease features that provide insights into the functioning of DNA repair genes. These studies have enabled us to identify some remarkable XP patients and better characterize different mechanisms of DNA repair. For example, we found XPC patients with splice lariat branch point mutations who had 3 to 5% of XPC mRNA but mild disease indicating that only a small amount of XPC is sufficient for some cancer protection. We found that NER proteins accumulate and persist at sites of DNA damage in XP-B cells. In contrast, these NER proteins rapidly accumulate but fail to persist in UV damaged XP-E cells. We found that the melanomas and nevi in the XP patients were different from those in the general population both clinically and histologically. They had a high proportion of mutations in the PTEN tumor suppressor gene (90% UV type), a lower frequency of mutations in BRAF, NRAS or KIT and rarely had the BRAF V600E mutation found in the general population. We plan to develop a protocol to attempt to reduce the melanoma risk in the XP patients by inhibition of the PTEN, mTOR pathway. About 12% of genetic diseases involve premature stop codons (PTC). We developed sensitive assay systems to detect readthrough of premature stop codons using cells from our collection with PTC in the XPC DNA repair gene. We found the aminoglycoside, gentamycin, can improve DNA repair in selected patients, permitting precise targeting of therapy to responsive individual cell lines. We are performing pre-clinical tests to determine if topical aminoglycosides can increase DNA repair without systemic toxicity. We found a 12 year old boy with melanoma, deafness and reduced DNA repair had a balanced translocation between chromosomes 9p and 22q which produced a dominant negative regulator of the tumor suppressor gene, p14arf, and the fetal developmental gene, TBX1. We are collaborating with NCI epidemiologists to study clinically normal family members of XP patients to determine if XP heterozygotes, who are much more frequent than XP patients, have increased cancer risk. We have 218 XP patients and family members in 50 families enrolled in this protocol. 2. TRICHOTHIODYSTROPHY In contrast to the profound environmental influence of sun exposure on XP, TTD is a disease of altered development. In our current natural history protocol we have ascertainedand intensively examined 55 TTD or XP/TTD patients and 104 TTD family members. This is the largest cohort of patients with this rare disorder in the world. In collaboration with gynecologists and epidemiologists we published 3 studies on pregnancy abnormalities in TTD. There was a high frequency of gestational abnormalities in pregnancies resulting in TTD affected offspring compared to pregnancies resulting in unaffected offspring from the same mothers or to the general population. These pregnancy complications were present only in pregnancies that had XP-D mutations that resulted in TTD offspring but not in XP-D mutations resulting in XP offspring. These observations provide important insights into the role of DNA repair genes in human pregnancy and fetal development. In collaboration with the ophthalmologists, we published a detailed report of the eye findings of 32 TTD patients we studied from 2001 to 2010. Infantile cataracts were present in more than half of these patients. Several young children with TTD have lost the ability to walk due to aseptic necrosis of the femoral head. Unfortunately, surgical treatment was followed by a series of post-operative complications leading to death. We are collaborating with radiologists to attempt to determine early signs of this problem and guide management. We have also found patients with features of more than one disease. Thus we identified 12 XP/TTD patients who have features of both XP and TTD and increased cancer risk. We are attempting to further define this entity by use of laboratory testing of DNA repair.

1。Xeroderma色素，我们自1971年以来一直在NIH检查XP患者。我们对XP患者的癌症，听力丧失和眼睛异常进行了长期随访研究。我们发现，20岁以下的XP患者患非黑色素瘤皮肤癌（NMSK）的风险增加了10,000倍，而黑色素瘤风险增加了2000倍。在我们的自然历史方案中，我们确定并深入研究了NIH的87个XP或Cockayne综合征（CS）患者（CS）患者和55 TTD或XP/TTD患者，并正在与国际研究人员合作研究其他患者。我们发布了4例XP患者的详细尸检报告 - 包括XP -D患者的第一次尸检。 XP-A和XP-D患者是患有严重神经变性的成年人，被发现患有婴儿大脑。现在，我们已经确定了当前已知的9个已知DNA核苷酸切除修复（NER）基因（XPA，XPA，XPB，XPC，XPD，XPD，XPE，XPF，XPF，XPG，XPG，ERCC1和TTDA），POL ETA，POL ETA和TTDDN1 IN近200名XP或TTD患者。我们已经建立了数百个经过精心记录的细胞系，并将它们贡献给细胞库以使用一般科学界。我们正在使用阵列比较基因组杂交（ACGH）和整个外显子组测序来寻找来自这些基因中没有突变的XP和TTD患者的其他基因中的突变。我们的实验室是美国的主要中心，涉及与DNA维修有关的疾病的基本，临床和翻译专业知识。我们正在积极寻求并开发了专业知识，以识别具有独特疾病特征的异常患者，这些患者可为DNA修复基因的功能提供见解。这些研究使我们能够确定一些显着的XP患者，并更好地表征了DNA修复的不同机制。例如，我们发现XPC患者患有剪接幼体分支点突变，其中3至5％的XPC mRNA，但轻度疾病表明只有少量XPC足以提供某些癌症保护。我们发现NER蛋白在XP-B细胞中DNA损伤部位积聚并持续存在。相比之下，这些NER蛋白质迅速积累，但无法持续在紫外线受损的XP-E细胞中。我们发现XP患者的黑色素瘤和NEVI与临床和组织学上的普通人群不同。它们在PTEN肿瘤抑制基因（90％UV型）中的突变比例很高，BRAF，NRAS或KIT突变的频率较低，并且很少在一般人群中发现BRAF V600E突变。我们计划通过抑制PTEN MTOR途径来制定试图降低XP患者黑色素瘤风险的方案。约有12％的遗传疾病涉及过早停止密码子（PTC）。我们开发了敏感的测定系统，以使用XPC DNA修复基因中的PTC中的PTC中的细胞来检测过早停止密码子的读取。我们发现氨基糖苷，庆大霉素可以改善选定患者的DNA修复，从而可以将治疗精确地靶向响应迅速的单个细胞系。我们正在进行临床前测试，以确定局部氨基糖苷是否可以增加DNA修复而无需全身毒性。我们发现一个12岁的男孩患有黑色素瘤，耳聋和DNA修复降低，染色体9p和22q之间的易位平衡，产生了肿瘤抑制基因的主要负调节剂，p14arf和胎儿发育基因TBX1，TBX1。我们正在与NCI流行病学家合作研究XP患者的临床正常家庭成员，以确定XP杂合子是否比XP患者频繁得多，会增加癌症的风险。我们有218名XP患者和家庭成员参加了该方案。 2。毛胸部营养不良与XP暴露对XP的深刻环境影响相反，TTD是一种改变发育的疾病。在当前的自然历史方案中，我们确定并深入研究了55个TTD或XP/TTD患者和104个TTD家庭成员。这是世界上这种罕见疾病的最大患者队列。与妇科医生和流行病学家合作，我们发表了3项有关TTD妊娠异常的研究。与怀孕相比，怀孕的妊娠异常频率很高，导致TTD影响后代，导致未受来自同一母亲或普通人群的后代。这些妊娠并发症仅存在于具有XP-D突变的妊娠中，导致TTD后代，但XP-D突变不导致XP后代。这些观察结果为DNA修复基因在人类妊娠和胎儿发育中的作用提供了重要的见解。与眼科医生合作，我们发表了一份详细的报告，讲述了我们从2001年至2010年研究的32例TTD患者的眼睛发现。这些患者中有一半以上存在婴儿白内障。由于股骨头的无菌坏死，有几个患有TTD的年幼儿童失去了行走的能力。不幸的是，手术治疗之后是一系列术后并发症，导致死亡。我们正在与放射科医生合作，试图确定此问题的早期迹象和指导管理。我们还发现患有多种疾病的患者。因此，我们确定了12名具有XP和TTD特征并增加癌症风险的XP/TTD患者。我们试图通过使用DNA修复实验室测试进一步定义该实体。