RESUMO
BACKGROUND: There is no established treatment to impede the progression or restore kidney function in human chronic kidney disease (CKD). AIM: To examine the efficacy of cultured human CD34+ cells with enhanced proliferating potential in kidney injury in mice. METHODS: Human umbilical cord blood (UCB)-derived CD34+ cells were incubated for one week in vasculogenic conditioning medium. Vasculogenic culture significantly increased the number of CD34+ cells and their ability to form endothelial progenitor cell colony-forming units. Adenine-induced tubulointerstitial injury of the kidney was induced in immunodeficient non-obese diabetic/severe combined immunodeficiency mice, and cultured human UCB-CD34+ cells were administered at a dose of 1 × 106/mouse on days 7, 14, and 21 after the start of adenine diet. RESULTS: Repetitive administration of cultured UCB-CD34+ cells significantly improved the time-course of kidney dysfunction in the cell therapy group compared with that in the control group. Both interstitial fibrosis and tubular damage were significantly reduced in the cell therapy group compared with those in the control group (P < 0.01). Microvasculature integrity was significantly preserved (P < 0.01) and macrophage infiltration into kidney tissue was dramatically decreased in the cell therapy group compared with those in the control group (P < 0.001). CONCLUSION: Early intervention using human cultured CD34+ cells significantly improved the progression of tubulointerstitial kidney injury. Repetitive administration of cultured human UCB-CD34+ cells significantly improved tubulointerstitial damage in adenine-induced kidney injury in mice via vasculoprotective and anti-inflammatory effects.
RESUMO
BACKGROUND: p51 (p73L/p63/p40/KET), a recently isolated novel p53 homologue, binds to p53-responsive elements to upregulate some p53 target genes and has been suggested to share partially overlapping functions with p53. p51 may be a promising candidate target molecule for anti-cancer therapy. METHODS: In this study, we adenovirally transduced p51A cDNA into human lung, gastric and pancreatic cancer cells and analyzed the intracellular function of p51 in anti-oncogenesis in vitro and in vivo. RESULTS: Overexpression of p51A revealed an anti-proliferative effect in vitro in all the cancer cells examined in this study. The anchorage-dependent and -independent cell growth of EBC1 cells carrying mutations in both p51 and p53 was suppressed and significant apoptosis following adenoviral transduction with p51 and/or p53 was seen. This growth suppression was cooperatively enhanced by the combined infection with adenoviral vectors encoding both p51 and p53. Furthermore, p51 activated several, but not all, p53-inducible genes, indicating that the mechanisms controlling p51- and p53-mediated tumor suppression differed. CONCLUSIONS: Our observations indicate that, although p51 exhibited reduced anti-oncogenetic effects compared with p53, it cooperatively enhanced the anti-tumor effects of p53. Our results suggest that p51 functions as a tumor suppressor in human cancer cells in vitro and in vivo and may be useful as a potential tool for cancer gene therapy.
Assuntos
Proteínas de Ligação a DNA/genética , Genes p53 , Terapia Genética/métodos , Neoplasias/terapia , Transativadores/genética , Proteínas Supressoras de Tumor/genética , Adenoviridae/genética , Animais , Apoptose , Sequência de Bases , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Primers do DNA/genética , Feminino , Vetores Genéticos , Humanos , Óperon Lac , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias/genética , Neoplasias/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Fatores de Transcrição , Transdução Genética , Transplante HeterólogoRESUMO
Patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) have poor prognosis despite intensive therapeutic intervention. Recently, imatinib, a BCR-ABL tyrosine kinase inhibitor, has been proven to be an effective treatment for Ph(+) ALL, but nearly all patients rapidly acquire resistance. High-dose imatinib administration might overcome this resistance; however, systemic toxicities would likely limit this approach. Therefore, a new delivery system allowing for the specific targeting of imatinib is urgently needed. Because almost all Ph(+) ALL cells express CD19 on their surface, we have developed an immunoliposome carrying anti-CD19 antibody (CD19-liposomes). The internalization efficiency of the CD19-liposomes approached 100% in all Ph(+) ALL cells but was very low in CD19(-) cells. The cytocidal effect of imatinib-encapsulated CD19-liposomes (imatinib-CD19-liposomes) on Ph(+) ALL cell lines and primary leukemia cells from patients with Ph(+) ALL was much greater than that of imatinib with or without control liposomes. Importantly, the imatinib-CD19-liposomes did not affect the colony formation of CD34(+) hematopoietic cells, even at inhibitory concentration of free imatinib. Taken together, these data clearly demonstrate that the imatinib-CD19-liposomes induced specific and efficient death of Ph(+) ALL cells. This new therapeutic approach might be a useful treatment for Ph(+) ALL with fewer side effects than free imatinib.