Laboratorio 103, Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, CDMX, Mexico.
Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Ciudad de México, Mexico.
Sci Rep. 2021 Apr 15;11(1):8210. doi: 10.1038/s41598-021-87560-w.
Generation 4 of polyamidoamine dendrimer (G4-PAMAM) has several biological effects due to its tridimensional globular structure, repetitive branched amides, tertiary amines, and amino-terminal subunit groups liked to a common core. G4-PAMAM is cytotoxic due to its positive charges. However, its cytotoxicity could increase in cancer cells due to the excessive intracellular negative charges in these cells. Furthermore, this work reports G4-PAMAM chemical structural characterization using UHPLC-QTOF-MS/MS (LC-MS) by electrospray ionization to measure its population according to its positive charges. Additionally, the antiproliferative effects and intracellular localization were explored in the HMC-1 and K-562 cell lines by confocal microscopy. The LC-MS results show that G4-PAMAM generated multivalent mass spectrum values, and its protonated terminal amino groups produced numerous positive charges, which allowed us to determine its exact mass despite having a high molecular weight. Additionally, G4-PAMAM showed antiproliferative activity in the HMC-1 tumor cell line after 24 h (IC = 16.97 µM), 48 h (IC = 7.02 µM) and 72 h (IC = 5.98 µM) and in the K-562 cell line after 24 h (IC = 15.14 µM), 48 h (IC = 14.18 µM) and 72 h (IC = 9.91 µM). Finally, our results showed that the G4-PAMAM dendrimers were located in the cytoplasm and nucleus in both tumor cell lines studied.
第四代聚酰胺-胺树枝状聚合物（G4-PAMAM）具有三维球形结构、重复的支链酰胺、叔胺和与共同核心相连的氨基末端亚基基团，因此具有多种生物学效应。G4-PAMAM 带正电荷，因此具有细胞毒性。然而，由于这些细胞内存在过多的负电荷，其细胞毒性在癌细胞中可能会增加。此外，本工作使用超高效液相色谱-四极杆飞行时间质谱联用（UHPLC-QTOF-MS/MS，LC-MS）通过电喷雾电离对 G4-PAMAM 的化学结构进行了表征，以根据其正电荷测量其丰度。此外，通过共聚焦显微镜研究了 G4-PAMAM 在 HMC-1 和 K-562 细胞系中的抗增殖作用和细胞内定位。LC-MS 结果表明，G4-PAMAM 产生了多价质谱值，其质子化末端氨基产生了大量正电荷，这使我们能够确定其确切分子量，尽管其分子量很高。此外，G4-PAMAM 在 HMC-1 肿瘤细胞系中在 24 小时（IC=16.97 µM）、48 小时（IC=7.02 µM）和 72 小时（IC=5.98 µM）后以及在 K-562 细胞系中在 24 小时（IC=15.14 µM）、48 小时（IC=14.18 µM）和 72 小时（IC=9.91 µM）后表现出抗增殖活性。最后，我们的结果表明，G4-PAMAM 树枝状聚合物在两种研究的肿瘤细胞系中均位于细胞质和细胞核中。
