A naked RNA heptamer targeting the human Bcl-2 mRNA induces apoptosis of HL60 leukemia cells.

tRNase Z(L)-utilizing efficacious gene silencing is a gene control technology, which is based on the property that tRNase Z(L) can cleave any target RNA under the direction of an appropriate small guide RNA (sgRNA). To find therapeutic sgRNAs to cure hematological malignancies, we investigated behavior of heptamer-type sgRNA. We demonstrated that a heptamer, mh1(Bcl-2), which targets the human Bcl-2 mRNA, can be taken up by cells without any transfection reagents and that it can induce apoptosis of the leukemia cells. Mouse xenograft experiments showed that a median survival of the mh1(Bcl-2)-treated mice was longer than that of the control mice.