Abstract

By 2003, the Human Genome project had been completed; however, it turned out that 97% of genome sequences did not encode proteins. The explanation came later when it was found the untranslated DNA contain sequences for short microRNAs (miRNAs) and long noncoding RNAs that did not produce any mRNAs or tRNAs, but instead were involved in the regulation of gene expression. Initially identified in the cytoplasm, miRNAs have been found in all cell compartments, where their functions are not limited to the degradation of target mRNAs. miRNAs that are secreted into the extracellular space as components of exosomes or as complexes with proteins, participate in morphogenesis, regeneration, oncogenesis, metastasis, and chemoresistance of tumor cells. miRNAs play a dual role in oncogenesis: on one hand, they act as oncogene suppressors; on the other hand, they function as oncogenes themselves and inactivate oncosuppressors, stimulate tumor neoangiogenesis, and mediate immunosuppressive processes in the tumors, The review presents current concepts of the miRNA biogenesis and their functions in the cytoplasm and nucleus with special focus on the noncanonical mechanisms of gene regulation by miRNAs and involvement of miRNAs in oncogenesis, as well as the authors’ opinion on the role of miRNAs in metastasis and formation of the premetastatic niche.

中文翻译：

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癌症中的微RNA：从基因表达调控到转移性生态位重编程

摘要

到2003年，人类基因组计划已经完成；然而，结果证明 97% 的基因组序列不编码蛋白质。后来发现未翻译的 DNA 包含短微 RNA (miRNA) 和长非编码 RNA 的序列，这些序列不产生任何 mRNA 或 tRNA，而是参与基因表达的调节。miRNA 最初在细胞质中被发现，在所有细胞区室中都被发现，它们的功能不仅限于目标 mRNA 的降解。miRNA作为外泌体的组成部分或与蛋白质的复合物分泌到细胞外空间，参与肿瘤细胞的形态发生、再生、肿瘤发生、转移和化学抗性。miRNA 在肿瘤发生中发挥双重作用：一方面，它们充当癌基因抑制因子；另一方面，