Epigenetic regulation of gene expression, without altering the DNA sequence, is involved in many normal cellular growth and division events, as well as diseases such as cancer. Epigenetics is no longer limited to DNA methylation, and histone modification, but regulatory non-coding RNAs (ncRNAs) also play an important role in epigenetics. Circular RNAs (circRNAs), single-stranded RNAs without 3′ and 5′ ends, have recently emerged as a class of ncRNAs that regulate gene expression. CircRNAs regulate phosphatase and tensin homolog (PTEN) expression at various levels of transcription, post-transcription, translation, and post-translation under their own regulation. Given the importance of PTEN as a tumor suppressor in cancer that inhibits one of the most important cancer pathways PI3K/AKT involved in tumor cell proliferation and survival, significant studies have been conducted on the regulatory role of circRNAs in relation to PTEN. These studies will be reviewed in this paper to better understand the function of this protein in cancer and explore new therapeutic approaches.

中文翻译：

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环状 RNA：癌症中 PTEN 表达和功能的表观遗传调节因子

基因表达的表观遗传调控在不改变 DNA 序列的情况下参与许多正常细胞生长和分裂事件以及癌症等疾病。表观遗传学不再局限于DNA甲基化和组蛋白修饰，调节性非编码RNA（ncRNA）也在表观遗传学中发挥着重要作用。环状 RNA (circRNA) 是一种没有 3' 和 5' 末端的单链 RNA，最近作为一类调节基因表达的 ncRNA 出现。 CircRNA 在其自身调节下在转录、转录后、翻译和翻译后的各个水平上调节磷酸酶和张力蛋白同源物 (PTEN) 的表达。鉴于 PTEN 作为癌症肿瘤抑制因子的重要性，它抑制参与肿瘤细胞增殖和存活的最重要的癌症途径之一 PI3K/AKT，因此人们对 circRNA 与 PTEN 相关的调节作用进行了重要研究。本文将回顾这些研究，以更好地了解这种蛋白质在癌症中的功能并探索新的治疗方法。