RESUMO
<p><b>OBJECTIVE</b>To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAM/VEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells.</p><p><b>METHODS</b>We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells.</p><p><b>RESULTS</b>The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly.</p><p><b>CONCLUSION</b>With a low toxicity, high safety, and high transfection rate, G4PAMAM/VEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.</p>
Assuntos
Humanos , Inibidores da Angiogênese , Genética , Neoplasias da Mama , Genética , Metabolismo , Patologia , Linhagem Celular Tumoral , Proliferação de Células , Dendrímeros , Regulação da Expressão Gênica , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Nylons , Oligodesoxirribonucleotídeos Antissenso , Genética , Farmacologia , RNA Mensageiro , Genética , Transgenes , Genética , Fator A de Crescimento do Endotélio Vascular , Genética , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To investigate the effect of G4PAMAM/VEGFASODN compound on expression of VEGF and VEGF mRNA in MDA-MB-231 breast cancer cells and the growth inhibition of vascular endothelial cells.</p><p><b>METHODS</b>The diameter of G4PAMAM/VEGFASODN granule was measured by transmission electron microscopy, and its stability under different pH was also observed. The efficiency of transfection in vitro was detected by flow cytometer and the positively transfected cells were detected by laser scanning confocal microscope. The survival rate and the inhibitory rate of vascular endothelial cells were determined by MTT assay. The expression of protein VEGF was detected by immunohistochemical method and the expression of VEGF mRNA was detected by RT-PCR.</p><p><b>RESULT</b>The diameter of G4PAMAM/VEGFASODN granules was about 10 nm and it arranged as homogeneous netlike. Under pH 5-10 G4PAMAM/VEGFASODN presented highly stable and no dissociation was observed with different charge ratios. The 48-hour transfection rate of G4PAMAM/VEGFASODN in charge ratio of 1:40 was significantly higher than that of the lipofectamine group. None of the transfection products in each group showed cell toxicity. The staining of VEGF protein in the cytoplasm of MDA-MB-231 cells after G4PAMAM/ASODN transfection weakened markedly, and the positive expression rate decreased. Meanwhile, the VEGF mRNA expression was also decreased.</p><p><b>CONCLUSION</b>With good stability and transfection rate, compound G4PAMAM/VEGFASODN can be a promising new nanometer vector of gene transfer system. The G4PAMAM/VEGFASODN can inhibit the expression of VEGF gene specifically and efficiently, which may be used for in vivo animal experiment.</p>