New Mechanism of Gemcitabine and Its Phosphates: DNA Polymerization Disruption via 3′–5′ Exonuclease Inhibition
作者:Shuzhang Yang、Danyan Luo、Na Li、Chuncheng Li、Shuo Tang、Zhen Huang
DOI:10.1021/acs.biochem.0c00543
日期:2020.11.17
Gemcitabine (dFdC), a modified deoxycytidine (dC) widely used in tumor treatment, is a prodrug that is phosphorylated to generate mono-, di-, and triphosphates. The triphosphate (dFdCTP) is incorporated into DNA to terminate DNA synthesis in cancer. Some incorporated dFdC nucleotides can be partially removed by the 3′–5′ exonuclease activity, namely its editing function, and the others escape the editing
吉西他滨(dFdC)是一种广泛用于肿瘤治疗的修饰的脱氧胞苷(dC),是一种被磷酸化以生成一磷酸,二磷酸和三磷酸的前药。将三磷酸酯(dFdCTP)掺入DNA以终止癌症中的DNA合成。一些掺入的dFdC核苷酸可以通过3'-5'核酸外切酶活性(即其编辑功能)部分除去,而其他的则可以逃避编辑。但是,尚不清楚dFdC是否有逃逸编辑的有效机制。我们首先发现,与dFdC不同,其单磷酸,二磷酸和三磷酸可以抑制DNA聚合酶I的3'–5'核酸外切酶,抑制编辑并允许有效的转义机制,而其聚合酶活性并未受到明显影响。因此,这些磷酸盐可防止去除掺入的dFdC残留物,从而积极阻断DNA的延伸和合成。这些磷酸盐的抑制效率遵循吉西他滨的单磷酸,二磷酸和三磷酸的增加顺序(dFdC