Discovery and Evaluation of Prioritized Mutations in Pancreatic Cancer

对癌症的机理理解在很大程度上依赖于突变的基因。这些基因包括导致家族肿瘤易感性的基因，控制复制保真度的基因，以及驻留在调节途径中的基因。 胰腺癌是一种异常有效的系统，可以用来识别独特的突变靶点，我们的研究小组对这些发现做出了重大贡献。这一成功在一定程度上是由于这种肿瘤类型中纯合子缺失的高度信息量的结构模式以及更高的基因组维持突变(特别是那些影响同源重组的突变)。有迹象表明，仍有许多隐性基因和额外的显性基因有待发现。 胰腺癌。大多数高危胰腺癌家族仍未被已知的突变所解释，大多数具有CIN(染色体不稳定)的癌症还没有与分子病因联系在一起。例如，新基因中的隐性突变目前被发现的速度比对其功能意义的诠释更快。 我们最近探索并发布了新获得的关键技术突破和特殊的肿瘤细胞资源，可以迅速加快这一研究路线。强大的高通量测序技术正在进行中，以帮助此类研究，但需要得到路线图的补充，该路线图来自我们正在开发的癌症基因组的战略性结构分析。 我们的特定目标将定位有希望的新突变基因的位置。对于有一些现有功能线索的基因，我们可以使用现有的检测方法来评估突变的影响。对于功能几乎没有线索的真正新的基因，我们可以使用我们为体细胞中的同源重组开发的技术来实现错义突变或基因破坏，通过基因特异性分析和原位异种移植来完成表型评估。对于具有未知功能分配和远距离进化保守的基因，将使用斑马鱼基因损伤模型来研究 功能和增强斑马鱼胰腺肿瘤发生能力的发育线索。后一种技术似乎令人惊讶，但似乎为新基因的分类提供了巨大的效率。 我们的长期目标是为未来胰腺癌的家族易感性、信号通路中断和基因组不稳定性的研究提供一个更完整的基础。

A mechanistic understanding of cancer rests heavily upon the mutated genes. These include genes causing familial tumor susceptibilities, governing replication fidelity, and residing in regulatory pathways. Pancreatic cancer is an unusually efficient system in which to identify distinctive mutational targets, discoveries to which our research group has contributed heavily. This success is due in part to highly informative structural patterns of homozygous deletions as well as a higher incidence of genome-maintenance mutations (especially those affecting homologous recombination) in this tumor type. Indications are that many recessive genes and perhaps additional dominant genes remain to be discovered in pancreatic cancer. Most of the high-risk pancreatic cancer families remain unexplained by known mutations, and most cancers having CIN (chromosomal instability) are not yet tied mechanistically to a molecular cause. Recessive mutations in novel genes, for example, are currently being discovered more rapidly than can be annotated for their functional significance. We recently explored and published key technical breakthroughs and special tumor cell resources that are newly available and can quickly accelerate this line of study. Powerful high-throughput sequencing techniques are underway to aid such studies, but will need to be complemented by a roadmap derived from a strategic structural analysis of the cancer genome such as we are developing. Our specific aims will locate promising sites of new mutant genes. For genes having some existing functional clues, we can assess the effects of mutation using available assays. For truly novel genes having few clues as to their function, we can achieve missense mutations or gene disruption using technologies we developed for homologous recombination in somatic cells, with phenotypic assessment accomplished both by gene-specific assays and by orthotopic xenografting. For genes having unknown functional assignment and distant evolutionary conservation, a zebrafish model of gene impairment will be used to survey for developmental clues to function and for an ability to augment zebrafish pancreatic tumorigenesis. This latter technique seems surprising, but appears to offer immense efficiency for classifying novel genes. Our long-term goal is to provide a more complete foundation for future studies of familial susceptibility, disrupted signaling pathways, and genome instability in pancreatic cancer.