PIWI/piRNA在癌症中的功能和机制

doi:10.3969/j.issn.0253-9608.2021.05.001

摘要/Abstract

摘要： PIWI蛋白是PAZ/PIWI结构域家族亚家族之一的RNA结合蛋白。PIWI蛋白通常与称为“PIWI相互作用的小型非编码RNA”(piRNA)相结合形成功能复合体来发挥作用。PIWI-piRNA通路因其在抑制转座子和生殖系发育方面的重要作用而闻名。除了在生殖系中的卓越作用，PIWI蛋白也因其通常只在生殖细胞中表达而在正常体细胞组织中几乎不表达，但是PIWI 蛋白在癌变的肿瘤组织里却异常表达，使其有望成为精准靶向治疗的绝佳靶点而在近年来备受关注。在这篇综述里，我们首先回顾PIWI蛋白如何与piRNA一起多面地调控生殖系中多种不同类型的RNA的表达，然后总结PIWI蛋白和piRNA在不同类型的癌症中的表达和功能，探讨近年来关于PIWI和piRNA在癌症研究中的局限性和可能存在的误区，并对最近冲击传统观念的PIWI在癌细胞中非piRNA依赖的生物学功能和调控机制展开深入的讨论。

关键词: PIWI, piRNA, 癌症

Abstract: PIWI proteins, a subfamily of PAZ/PIWI domain (PPD) family RNA-binding proteins, are best known for their functions in silencing transposons and germline development by partnering with small noncoding RNA called PIWI-interacting RNA (piRNA). In addition to its prominent role in the germline, PIWI proteins are gaining increasing interests for cancer research because they are usually hardly expressed in somatic tissues but gain abnormal expression in cancer cells, making them promising targets for precision therapy. In this review, we first provide an overview on how PIWI proteins, together with piRNAs, multifacetedly regulate the expression of major classes of RNA in germ cells. Then, we summarize the expression and function of PIWI proteins and piRNAs in different types of cancer and consider the limitations and possible misunderstanding of PIWI and piRNA in cancer research. In addition, we discuss the recently discovered piRNA-independent functions and regulatory mechanisms of PIWI in cancer cells that have the traditional concept.

Key words: , PIWI, piRNA, cancer

石硕, 王晨, 林海帆. PIWI/piRNA在癌症中的功能和机制[J]. 自然杂志, 2021, 43(5): 313-322.

SHI Shuo, WANG Chen, LIN Haifan. Function and mechanism of PIWI/piRNA in cancer[J]. Chinese Journal of Nature, 2021, 43(5): 313-322.

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