Regulatory functions of miR‑200b‑3p in tumor development (Review).

MicroRNAs (miRNAs/miRs), non‑coding single‑stranded RNAs of length 18‑24 nucleotides, can modulate gene expression through post‑transcriptional control. As such, they can influence tumor proliferation, apoptosis, invasion, metastasis as well as chemotherapy resistance by regulating certain downstream genes. In this context, miR‑200b‑3p, one particular member of the miR‑200 family, possesses the ability to suppress tumor progression. However, many studies have suggested that, in certain cases, this miRNA may also promote the development of some tumors due to differences in the microenvironments and molecular backgrounds of different cancers. This review summarizes previous studies on the involvement of miR‑200b‑3p in tumors, including the underlying mechanism.