MicroRNAs (miRNAs) are non-coding RNAs with a length of 18–22 nucleotides that regulate about a third of the human genome at the post-transcriptional level. MiRNAs are involved in almost all biological processes, including cell proliferation, apoptosis, and cell differentiation, but also play a key role in the pathogenesis of many diseases. Most miRNAs are expressed within the cells themselves. Due to various forms of transport from cells like exosomes, circulating miRNAs are stable and can be found in human body fluids, such as blood, saliva, cerebrospinal fluid, and urine. Circulating miRNAs are of great interest as potential noninvasive biomarkers for tumors, lipid disorders, diabetes mellitus, and cardiovascular diseases. However, the possibility of their use in the clinic is limited, and this is associated with a number of problems since currently there are significant differences between the procedures for processing samples, methods of analysis, and especially strategies for standardizing results. Moreover, miRNAs can represent not only potential biomarkers but also become new therapeutic agents and be used in modern clinical practice, which again confirms the need for their study.

中文翻译：

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MiRNA作为生物标志物和治疗工具的当前状态。

MicroRNA（miRNA）是长度为18-22个核苷酸的非编码RNA，在转录后水平上可调节约三分之一的人类基因组。MiRNA参与几乎所有生物过程，包括细胞增殖，凋亡和细胞分化，但在许多疾病的发病机理中也起着关键作用。大多数miRNA在细胞自身中表达。由于来自外泌体等细胞的各种运输形式，循环的miRNA是稳定的，可以在人体液中找到，例如血液，唾液，脑脊髓液和尿液。循环miRNA作为潜在的非侵入性生物标记物，可用于治疗肿瘤，血脂异常，糖尿病和心血管疾病，引起人们极大的兴趣。但是，它们在临床中使用的可能性是有限的，由于当前在处理样品的程序，分析方法，尤其是标准化结果的策略之间存在显着差异，因此这与许多问题有关。此外，miRNA不仅可以代表潜在的生物标志物，而且可以成为新的治疗剂，并可以用于现代临床实践，这再次证实了对其进行研究的必要性。