In this regard, Finlay and colleagues reported that the delivery of TWIST1-targeting siRNAs with a polyethyleneimine-coated mesoporous silica nanoparticle (MSN) was able to revert the mesenchymal phenotype of MDA-MB-435S melanoma cells, thus leading to the inhibition of migratory potential and tumor burden in vivo [85]. The gene discussed is TWIST1; the disease is neoplasm.