PDF(Pubmed)
Abstract：
Docetaxel (Doc) plays a crucial role in clinical antineoplastic practice. However, it is continuously documented that tumors frequently develop chemoresistance and relapse, which may be related to polyploid giant cancer cells (PGCCs). The aim of this study was investigate the formation mechanism and biological behavior of PGCCs induced by Doc. Ovarian cancer cells were treated with Doc, and then the effect of Doc on cellular viability was evaluated by MTT assay and microscopic imaging analysis. The biological properties of PGCCs were further evaluated by Hoechst 33342 staining, cell cycle and DNA content assay, DNA damage response (DDR) signaling detection, β-galactosidase staining, mitochondrial membrane potential detection, and reverse transcription-quantitative polymerase chain reaction. The results indicated that Doc reduced cellular viability; however, many cells were still alive, and were giant and polyploid. Doc increased the proportion of cells stayed in the G2/M phase and reduced the number of cells. In addition, the expression of γ-H2A.X was constantly increased after Doc treatment. PGCCs showed senescence-associated β-galactosidase activity and an increase in the monomeric form of JC-1. The mRNA level of octamer-binding transcription factor 4 (OCT4) and krüppel-like factor 4 (KLF4) was significantly increased in PGCCs. Taken together, our results suggest that Doc induces G2/M cell cycle arrest, inhibits the proliferation and activates persistent DDR signaling to promote the formation of PGCCs. Importantly, PGCCs exhibit a senescence phenotype and express stem cell markers.
摘要：
多西他赛（Doc）在临床抗肿瘤实践中起着至关重要的作用。然而,不断有证据表明，肿瘤经常发生化学耐药性和复发，这可能与多倍体巨癌细胞（PGCC）有关。本研究的目的是探讨Doc诱导的PGCCs的形成机制和生物学行为。卵巢癌细胞用Doc治疗，然后通过MTT测定和显微成像分析评估Doc对细胞活力的影响。通过Hoechst33342染色进一步评估PGCC的生物学特性，细胞周期和DNA含量测定，DNA损伤反应（DDR）信号检测，β-半乳糖苷酶染色,线粒体膜电位检测，和逆转录-定量聚合酶链反应。结果表明Doc降低了细胞活力；然而，许多细胞还活着，是巨大的多倍体。Doc增加了停留在G2/M期的细胞比例并减少了细胞数量。此外,γ-H2A的表达。在Doc治疗后X不断增加。PGCC显示衰老相关的β-半乳糖苷酶活性和JC-1单体形式的增加。PGCC中八聚体结合转录因子4（OCT4）和krüppel样因子4（KLF4）的mRNA水平显着增加。一起来看,我们的结果表明，Doc诱导G2/M细胞周期停滞，抑制增殖并激活持续的DDR信号以促进PGCC的形成。重要的是,PGCC表现出衰老表型并表达干细胞标志物。
