Guerrero-Preston Rafael
Department of Otolaryngology, Head and Neck Cancer Research, Johns Hopkins School of Medicine, USA.
P R Health Sci J. 2008 Dec;27(4):350-6.
Racial, ethnic and class disparities in cancer incidence and mortality have been well documented. Disparities in the utilization of preventive, curative and treatment services among ethnic minorities have been reported. Screening can be effective at detecting cancer at treatable stages, but a large proportion of people at risk have not been screened or are not regularly screened, as recommended by the American Cancer Society's national guidelines. Early detection technologies have the potential of both influencing mortality from cancer, as well as enhancing primary prevention through detection and removal of lesions that could potentially develop into cancer. Cancer is an epigenetic disease characterized by the breakdown of DNA methylation and histones modification patterns. Epigenetic approaches may contribute to a reduction in cancer health disparities impacting early detection and increasing cancer treatment options. Epigenetic events represent important mechanism(s) by which gene function is selectively activated or inactivated, through genetic and non-genetic manifestations. Emerging evidence indicates that various epigenetic alterations, such as global histones modifications and DNA hypomethylation, common to most types of cancer, are modified by environmental exposures throughout the life course. A simple, easily explained and easy to understand non-invasive test, such as the DNA methylation index, that may screen for several cancer sites at once, may remove some of the existing barriers to cancer screening utilization, and contribute to the reduction of cancer disparities. Epigenetic approaches may also prove to be useful in identifying environmental and lifestyle factors that contribute to the prevalence of other chronic conditions in high risk populations, such as Puerto Rican populations in the United States and Puerto Rico.
癌症发病率和死亡率方面的种族、族裔和阶层差异已有充分记录。有报告称少数族裔在预防、治愈和治疗服务利用方面存在差异。筛查在可治疗阶段检测癌症方面可能有效,但很大一部分有风险的人未按照美国癌症协会的国家指南进行筛查或未定期筛查。早期检测技术既有可能影响癌症死亡率,也有可能通过检测和切除可能发展成癌症的病变来加强一级预防。癌症是一种表观遗传疾病,其特征是DNA甲基化和组蛋白修饰模式的破坏。表观遗传学方法可能有助于减少影响早期检测的癌症健康差异,并增加癌症治疗选择。表观遗传事件代表了通过遗传和非遗传表现选择性激活或失活基因功能的重要机制。新出现的证据表明,大多数类型癌症共有的各种表观遗传改变,如整体组蛋白修饰和DNA低甲基化,在整个生命过程中会受到环境暴露的影响。一种简单、易于解释和理解的非侵入性检测方法,如DNA甲基化指数,可同时筛查多个癌症部位,可能会消除现有癌症筛查利用的一些障碍,并有助于减少癌症差异。表观遗传学方法在识别导致高危人群(如美国和波多黎各的波多黎各人群)中其他慢性病流行的环境和生活方式因素方面也可能被证明是有用的。