Document Detail

Cell-penetrating TAT-FOXO3 fusion proteins induce apoptotic cell death in leukemic cells.
MedLine Citation:
PMID:  21220490     Owner:  NLM     Status:  In-Process    
FOXO proteins are Akt-regulated transcription factors involved in the control of cell cycle, DNA repair, stress defense, apoptosis, and tumor suppression. We reported that plasmid-based overexpression of constitutively active FOXO3 in cells from chronic lymphocytic leukemia (CLL) reduced their survival, suggesting that increasing FOXO3 activity in hematologic malignancies may represent a promising therapeutic strategy. The transactivating transcription factor (TAT) protein transduction domain (PTD) derived from the HIV TAT protein was shown to efficiently deliver macromolecular cargo in various cell types. In this study, wild-type FOXO3 and FOXO3 mutated on Akt sites [FOXO3 T32A/S253A/S315A or TM (triple mutant)] were fused to the TAT-PTD. Using biochemical techniques, flow cytometry, and microscopy analysis, we found a rapid and dose-dependent cell penetration into leukemic cells of unlabeled and fluorescein isothiocyanate-labeled TAT-FOXO3 fusion proteins followed by their accumulation within nuclear and cytoplasmic compartments. Treatment with TAT-FOXO3 TM-but not wild-type TAT-FOXO3-proteins induced Jurkat and K562 leukemic cell death and affected cell viability of other hematologic malignancies including primary cells from CLL. Cell transduction with TAT-FOXO3 TM induced apoptotic cell death as shown by morphologic changes, Annexin V/7-AAD (7-amino-actinomycin D) staining, activation of effector caspases, and PARP cleavage, caspase blockade through the use of the inhibitor Z-VAD, and expression of Bim and p27(KIP1). By contrast, TAT-FOXO3 TM blocked cell proliferation of primary T cells, without affecting their viability. Together, our data show that cell penetrating TAT-FOXO3 TM fusion proteins constitute novel potential therapeutic agents in the treatment of lymphoproliferative disorders and hematologic malignancies.
Makram Essafi; Alice D Baudot; Xavier Mouska; Jill-Patrice Cassuto; Michel Ticchioni; Marcel Deckert
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Molecular cancer therapeutics     Volume:  10     ISSN:  1538-8514     ISO Abbreviation:  Mol. Cancer Ther.     Publication Date:  2011 Jan 
Date Detail:
Created Date:  2011-01-11     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101132535     Medline TA:  Mol Cancer Ther     Country:  United States    
Other Details:
Languages:  eng     Pagination:  37-46     Citation Subset:  IM    
Copyright Information:
©2010 AACR.
INSERM UMR 576, Hôpital de l'Archet, 151 Route de Saint-Antoine de Ginestiére, B.P. 3079, 06202, Nice Cedex 3, France.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Targeting tyrosine phosphorylation of PCNA inhibits prostate cancer growth.
Next Document:  Prediction of colorectal cancer relapse and prognosis by tissue mRNA levels of NDRG2.