营养与肿瘤表观遗传学关系的研究进展——组蛋白修饰机制

Research Progress on the Relationship between Nutrition and Cancer Epigenetics——Histone Modification Mechanisms

表观遗传学是研究没有DNA序列变化,但可遗传的基因表达(活性)的改变。目前认为表观遗传的信息包括核小体构型的变化(ATP依赖的染色体重构);基因组印记;X染色体失活;DNA甲基化;染色体蛋白的改变,包括组蛋白的修饰如乙酰化、甲基化、磷酸化、多聚ADP-核糖基化、赖氨酸残基(Lys)的生物素(酰)化等,组蛋白变体的替换,非组蛋白的改变;非编码RNA调控转录。长期以来人们一直认为基因突变参与肿瘤的形成,近年来越来越多的证据表明,肿瘤的形成受遗传学修饰和表观遗传修饰的影响,表观遗传修饰在肿瘤进展中同样具有非常重要的作用。饮食是影响健康的重要因素,与肿瘤关系密切。本文对有关表观遗传学的组蛋白修饰机制的研究作一综述,并分别对目前其在肿瘤发生、发展的分子机制研究中所起作用及其在肿瘤预防和治疗的应用方面进行初步总结;概述了食物营养与肿瘤表观遗传学组蛋白修饰机制关系的近期研究情况。

Epigenetics is the study of processes that establish metastable （ that is, somatically heritable） state of gene expression without altering the sequence. Epigenetic information includes nucleosome remodeling; genomic imprinting; X chromosome inactivation; DNA methylation; chromosome protein changes, including histone modification [acetylation, methylation, phosphorylation, poly （ADP-ribosylation） , lysine （K） residue biotinylation, and so on] , histone variants exchange, non-histone changes; and uncoding RNA-regulating transcription. Carcinogenesis springs from the combined forces of both genetic and epigenetic events. Although the importance of genetic mutations in cancer has long been recognized , the role of epigenetic modification has been suggested more recently. Nutrients play essential roles in human health, and may modify cancer risk. This article sumed up recent researches on histone modification mechanism, approached the molecular mechanism during cancer initiation and development and the application in cancer prevention and treatment in histone modification level respectively, and summarized the relationship between diet nutrition and cancer epigenetic mechanism in histone modification level.