In this context,microRNAs have emerged as potential therapeutic targets but stillpresent some limitations for in vivo applications.Particularly, miR-200c-3p is a well-known tumor suppressor microRNAthat inhibits tumor progression and metastasis in breast cancer throughdownregulating ZEB1 and ZEB2. Basedon the above, we describe the design and validation of a nanodeviceusing mesoporous silica nanoparticles for miR-200c-3p delivery forbreast cancer treatment. This evidence concerns the gene ZEB1 and cancer.