人类癌症体质逆转换的景观
Eunjung Lee1, Rebecca Iskow, Lixing Yang
1Center for Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA.
概括
可移植元素 (TE) 可以插入人类基因组,可能导致癌症. 这项研究发现,体质TE插入在上皮瘤中,影响基因表达,并与DNA低甲基化有关.
科学领域:
- 基因组学就是基因组学.
- 癌症生物学 癌症生物学
- 分子遗传学 分子遗传学
背景情况:
- 可移植元素 (TE) 是人类基因组中普遍存在的移动DNA序列.
- 通常抑制的TE活性可以在癌症中重新激活,可能导致突变.
- 通过RNA中间体的逆转换是TE传播的关键机制.
研究的目的:
- 研究体质可移植元素插入在人类癌症中的发生和影响.
- 分析这些插入的基因组位置和潜在的功能后果.
- 为了确定TE活动的癌症特异性模式.
主要方法:
- 在五种癌症类型中对43种瘤进行全基因组测序 (WGS).
- 对可转换元素插入的单核酸分辨率分析.
- 在瘤中的体内插入与匹配的正常组织中的生殖线插入的比较.
主要成果:
- 在分析的癌症基因组中确定了194个高保证度的体质TE插入.
- 在上皮瘤中检测到体质TE插入,但在血液和脑癌中没有.
- 在癌症相关基因中发现了体长间隔核元素1 (L1) 插入,影响基因表达并与低甲基化区域相关联.
结论:
- 实体性可移植元素插入,特别是L1,在某些人类癌症中是活跃的.
- 这些插入可以破坏基因功能和表达,导致瘤发生.
- TE活性与癌症特异性表观遗传变化有关,例如DNA低甲基化.
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