**Abstract**

As master modulators of the human genome, miRNAs are involved in all cancer hallmarks, disrupting the normal function of their targets. By gaining or losing the function, miRNAs lead to the validation of tumor phenotype, its progression, and metastasis as well as to drug resistance. Increasing the evidence suggests that the modulation of miRNAs in cancer cells, by suppressing the oncogenic miRNAs (oncomiRs) and substituting the deficient tumor suppressive miRNAs (TS-miRNAs), could become a reliable tool for improving the cancer therapy. In this chapter, we will present an up-to-date overview of the role of miRNA-based therapeutics in oncology, highlighting their role in cancer management, how these therapies can be used, and which would be the future challenges related to miRNA-based therapies.

**Keywords:** cancer, invasions, metastasis, miRNA, therapy
