GRACIELA APARECIDA BROCARDO
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina
2 resultados
Resultados de Busca
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- Azidothymidine is Effective Against Human Multiple Myeloma: A New Use for an Old Drug?(2013) PEREIRA, Juliana; LEVY, Debora; RUIZ, Jorge L. M.; BROCARDO, Graciela A.; FERREIRA, Kleber A.; COSTA, Renata O.; QUEIROZ, Rodrigo G.; MARIA, Durvanei A.; HALLACK NETO, Abrahao E.; CHAMONE, Dalton A. F.; BYDLOWSKI, Sergio P.Azidothymidine (AZT) is an antiretroviral drug that affects cell proliferation, apoptosis, and the NF-kappa B pathway. As multiple myeloma (MM) presents with constitutive activation of NF-kappa B, we analyzed the effect of AZT on human MM cell lines. We evaluated the cytotoxic effect of AZT in human MM cell lines sensitive (8226/S) or resistant to doxorubicin (8226/DX5) and human T cell lymphoblast-like cells, uterine sarcoma cells, and HUVEC using MTT assay. Cytotoxicity was also evaluated in vivo in nude mice xenografted with 8226/S tumor. The effect of AZT on the expression of genes involved in cell proliferation, apoptosis, angiogenesis, and the NF-kappa B pathway was analyzed in the xenografts using real-time polymerase chain reaction. AZT was effective against both 8226/S and 8226/DX5 cells in a dose and time-dependent manner (p = 0.02) in vitro and promoted cell cycle arrest in S phase in these cells. The tumor volume was lower in mice treated with AZT compared to untreated mice (p = 0.0003). AZT down-regulated the pro-proliferative genes encoding AKT1, MYC, STAT1, MAPK8, MAPK9, CCL-3, Bcl-3, and cyclin D2; pro-angiogenenic genes encoding VEGF and IL8; and genes involved in cell adhesion (ICAM1 and FN1) and the NF-kappa B pathway. AZT up-regulated the expression of tumor suppressor gene FOXP1 and the pro-apoptotic genes encoding BID, Bcl-10, and caspase-8. Thus, we demonstrated the cytotoxic effect of AZT in human MM cell lines for the first time. Our data may provide the rationale for future clinical trials of AZT for treating MM.
conferenceObject IN VITRO AND IN VIVO ANTITUMOR EFFECTS OF AZIDOTHYMIDINE IN A HUMAN MULTIPLE MYELOMA CELL LINE(2012) LEVY, Debora; RUIZ, Jorge Luis; BROCARDO, Graciela; FERREIRA, Adilson; QUEIROZ, Rodrigo; MARIA, Durvanei; BYDLOWSKI, Sergio; PEREIRA, JulianaBackground: Azidothymidine (AZT) is an antiretroviral nucleoside analogous inhibitor ofreverse transcriptase with known effects on cell proliferation, apoptosis, and angiogenesis Multiple myeloma is a severe disease and one of the steps involved in the malignant transformation of plasma cells is the activation of the nuclear factor kappa B (NF-κB) pathway. Objective: Evaluate the in vitro cytotoxic activity of AZT in human myeloma cell lines (RPMI 8226/S and RPMI 8226/Dx5) as well as in other cell lines: human T cell lymphoblast-like, T cell leukemia, uterine sarcoma and HUVEC. The in vivo effect was also evaluated in tumor xenograft model of human multiple myeloma in nude mice. Methods: Cells were treated with increasing concentrations of AZT (32.2 to 500μM) for 24 to 72 hours. Cytotoxicity was measured by MTT. Cell cycle and proteins Bcl-2 and p53 were evaluated by flow cytometry. For the in vivo experiments, 1x107 RPMI 8226/S cells were injected SC in the right flank of nude mice. After 7 days, animals were treated or not with AZT 12.5 μM IV every other day for 5 weeks. Thirty five genes were then investigated in the grafted tumor cells by real time polymerase chain reaction. Results: AZT showed in vitro antitumor activity in cell lines 8226/S and 8226/Dx5 in a dose and time dependent way (p = 0.02), but not in the other studied cells. Histological signs of apoptosis were seen, such as cytoplasmic blebs, nuclear condensation. A significant decrease of Bcl-2 (p<0.001) and p53 (p = 0.0139) proteins was observed in cells treated with AZT. A cell cycle arrest in Sphase was also seen after 72 hours of treatment with AZT 62.5 μM. Tumor volume in nude mice reated with AZT was reduced (p = 0.0003). In these tumors, AZT decreased the expression of genes associated with cell proliferation (AKT1, MYC, STAT1, MAPK8, MAPK9, CCL-3, Bcl-3 and Cyclin D2), angiogenesis (VEGF, IL8), cell adhesion (ICAM1 and FN1) and NF-κB. Moreover, also in tumors, AZT induced expression of the tumor suppressor gene FOXP1, pro-apoptotic genes BID, Bcl-10 and caspase-8. Conclusion: Azidothymidine promotes a cytotoxic effect in human multiple myeloma cells both in vitro and in vivo. This action involves the cell cycle arrest in S phase, inhibition of expression of genes that activate cell proliferation, as well as proangiogenic genes and NF- κB, and activation of apoptosis genes. Therefore, AZT could be potentially promising in the treatment of multiple myeloma.