Department of Cell Biology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, 76107, USA.
Cancer Chemother Pharmacol. 2010 Oct;66(5):945-52. doi: 10.1007/s00280-010-1246-8. Epub 2010 Jan 26.
NSC109268 has been described previously as inhibitor of proteasomal degradation and of phosphatase 2Calpha. In a yeast screen, we isolated NSC109268 as an agent altering sensitivity to DNA-damaging agents. We found that NSC109268 and the related compound NSC109272 enhance cellular sensitivity to cis- and transplatin but reduce sensitivity to nitrogen mustard. We explored if similar effects could be found in human cancer cells and if cell cycle analysis could hint at the underlying molecular mechanism.
Haploid yeast cells were treated in suspension with platinum agents and nitrogen mustard alone or in combination with NSC compounds, and survival was measured by colony-formation assays. Sensitivity of ovarian and prostate cancer cells toward these treatments was evaluated using the MTS assay. Cell cycle progression was determined by flow cytometry.
The enhancement of cisplatin sensitivity by NSC109268 found in yeast was confirmed in cisplatin-sensitive and cisplatin-resistant human ovarian cancer lines and in prostate cancer cells. In yeast and in human carcinoma cells, a correlation of enhanced sensitivity with delaying S-phase progression was revealed.
The known activities of NSC109268 as proteasome or phosphatase inhibitor could explain the phenotype of S-phase delay by assuming a higher initial DNA damage load, inhibition of DNA translesion synthesis or extended checkpoint arrest.
先前已将 NSC109268 描述为蛋白酶体降解和磷酸酶 2Calpha 的抑制剂。在酵母筛选中，我们分离出 NSC109268，作为一种改变对 DNA 损伤剂敏感性的试剂。我们发现 NSC109268 和相关化合物 NSC109272 增强了细胞对顺铂和反铂的敏感性，但降低了对氮芥的敏感性。我们探讨了在人类癌细胞中是否可以发现类似的作用，以及细胞周期分析是否可以暗示潜在的分子机制。
用铂剂和氮芥单独或与 NSC 化合物一起在悬浮液中处理单倍体酵母细胞，并通过集落形成测定法测量存活率。使用 MTS 测定法评估卵巢和前列腺癌细胞对这些处理的敏感性。通过流式细胞术确定细胞周期进程。
在酵母中发现的 NSC109268 增强顺铂敏感性的作用在顺铂敏感和耐顺铂的人卵巢癌细胞系和前列腺癌细胞中得到了证实。在酵母和人类癌细胞中，增强敏感性与 S 期进程延迟相关。
NSC109268 的已知活性作为蛋白酶体或磷酸酶抑制剂，可以通过假设更高的初始 DNA 损伤负荷、抑制 DNA 跨损伤合成或延长检查点阻滞来解释 S 期延迟的表型。
