Wild-type p53 gene transfer is not detrimental to normal cells in vivo: implications for tumor gene therapy.
The p53 oncosuppressor is strictly maintained in an inactive form under normal conditions, while it is post-translationally activated by a variety of stresses, enacting different protective biological functions. Since one critical issue in cancer gene therapy is tumor specificity, we asked whether the tight p53 regulation applies also to exogenously transferred p53. In principle, this type of regulation could allow p53 gene transfer in both normal and tumor cells to produce detrimental effects only in the latter ones. Here, we report that primary bone marrow cells infected with a p53 recombinant retrovirus and transplanted into irradiated mice reconstitute the hematopoietic system, with no detectable alterations in any of its compartments. Furthermore, simultaneous infection of leukemia and bone marrow cells depleted the neoplastic contamination, allowing lifelong, disease-free survival of 65% of the transplanted animals. These results show that exogenous p53 is controlled as tightly as the endogenous one, and opens the way to p53 gene therapy, without requiring tumor targeting.
Bossi
Gianluca
G
Department of Experimental Oncology, Molecular Oncogenesis Laboratory, Regina Elena Cancer Institute, Via delle Messi d'Oro 156, Rome 00158, Italy.
Mazzaro
Giuseppina
G
Porrello
Alessandro
A
Crescenzi
Marco
M
Soddu
Silvia
S
Sacchi
Ada
A
D000818:Animals; D001854:Bone Marrow Cells / Q000378:metabolism; D016465:Bone Marrow Purging; D002470:Cell Survival; D002478:Cells, Cultured; D005260:Female; D016158:Genes, p53 / Q000235:genetics; D015316:Genetic Therapy; D007938:Leukemia / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D009928:Organ Specificity; D012190:Retroviridae / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism*
D016159:Tumor Suppressor Protein p53