Specific killing of Ph+ chronic myeloid leukemia cells by a lentiviral vector-delivered anti-bcr/abl small hairpin RNA.
Chronic myeloid leukemia (CML) is characterized by a reciprocal chromosomal translocation between chromosomes 9 and 22 t(9;22)(q34;q11) that causes fusion of the bcr and abl genes. Transcription and splicing of the fusion gene generate two major splice variants of the bcr/abl transcript that encode an oncoprotein with tyrosine kinase activity. We have taken advantage of lentiviral vectormediated delivery of anti-bcr/abl short hairpin RNAs (shRNA) to downregulate the bcr/abl transcript in Philadelphia chromosome-positive (Ph+) K562 leukemia cells. This downregulation caused complete inhibition of proliferation of these cells and was accompanied by >90% inhibition of the bcr/abl transcript and p210 protein. These results demonstrate the feasibility of using a lentiviral vector to stably transduce therapeutic shRNAs into leukemia cells for the potential ex vivo purging of Ph+ cells in an autologous hematopoietic cell transplant setting. Furthermore, the robust expression of the shRNAs from our lentiviral vector suggests that this system could be generally useful for the expression of other shRNAs.
Division of Molecular Biology, City of Hope Medical Center and Beckman Research Institute, Duarte, CA 91010, USA.
Ming-Jie
MJ
Li
Ross
R
McMahon
David S
DS
Snyder
Jiing-Kuan
JK
Yee
John J
JJ
Rossi
D001483:Base Sequence; D002455:Cell Division; D016044:Fusion Proteins, bcr-abl / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D020868:Gene Silencing; D005822:Genetic Vectors; D006801:Humans; D020014:K562 Cells; D016086:Lentivirus / Q000235:genetics*; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000473:pathology*; D010677:Philadelphia Chromosome; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D012333:RNA, Messenger; D034741:RNA, Small Interfering; D016044:Fusion Proteins, bcr-abl