Maintaining good miRNAs in the body keeps the doctor away?: Perspectives on the relationship between food‐derived natural products and microRNAs in relation to exosomes/extracellular vesicles

During the last decade, it has been uncovered that microRNAs (miRNAs), a class of small non‐coding RNAs, are related to many diseases including cancers. With an increase in reports describing the dysregulation of miRNAs in various tumor types, it has become abundantly clear that miRNAs play significant roles in the formation and progression of cancers. Intriguingly, miRNAs are present in body fluids because they are packed in exosomes/extracellular vesicles and released from all types of cells. The miRNAs in the fluids are measured in a relatively simple way and the profile of miRNAs is likely to be an indicator of health condition. In recent years, various studies have demonstrated that some naturally occurring compounds can control tumor‐suppressive and oncogenic miRNAs in a positive manner, suggesting that food‐derived compounds could maintain the expression levels of miRNAs and help maintain good health. Therefore, our daily food and compounds in food are of great interest. In addition, exogenous diet‐derived miRNAs have been indicated to function in the regulation of target mammalian transcripts in the body. These findings highlight the possibility of diet for good health through the regulation of miRNAs, and we also discuss the perspective of food application and health promotion. Recently, various studies have shown that some natural compounds can control tumor‐suppressive and oncogenic miRNAs in a positive manner. In addition, some studies have raised the possibility that food‐derived miRNA/EVs might function after oral intake. We will have discussions about their contributions to the prevention of diseases and the maintenance of good health.