Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-236 Lodz, Poland.
Department of Medical Biochemistry, Medical University of Lodz, 92-216 Lodz, Poland.
Int J Mol Sci. 2024 Aug 23;25(17):9134. doi: 10.3390/ijms25179134.
DNA repair proteins became the popular targets in research on cancer treatment. In our studies we hypothesized that inhibition of DNA polymerase theta (Polθ) and its combination with Poly (ADP-ribose) polymerase 1 (PARP1) or RAD52 inhibition and the alkylating drug temozolomide (TMZ) has an anticancer effect on glioblastoma cells (GBM21), whereas it has a low impact on normal human astrocytes (NHA). The effect of the compounds was assessed by analysis of cell viability, apoptosis, proliferation, DNA damage and cell cycle distribution, as well as gene expression. The main results show that Polθ inhibition causes a significant decrease in glioblastoma cell viability. It induces apoptosis, which is accompanied by a reduction in cell proliferation and DNA damage. Moreover, the effect was stronger when dual inhibition of Polθ with PARP1 or RAD52 was applied, and it is further enhanced by addition of TMZ. The impact on normal cells is much lower, especially when considering cell viability and DNA damage. In conclusion, we would like to highlight that Polθ inhibition used in combination with PARP1 or RAD52 inhibition has great potential to kill glioblastoma cells, and shows a synthetic lethal effect, while sparing normal astrocytes.
DNA 修复蛋白成为癌症治疗研究中的热门靶点。在我们的研究中，我们假设抑制 DNA 聚合酶θ（Polθ）及其与聚（ADP-核糖）聚合酶 1（PARP1）或 RAD52 抑制的组合，以及烷化剂替莫唑胺（TMZ）对神经胶质瘤细胞（GBM21）具有抗癌作用，而对正常的人类星形胶质细胞（NHA）的影响较小。通过分析细胞活力、细胞凋亡、增殖、DNA 损伤和细胞周期分布以及基因表达来评估化合物的作用。主要结果表明，Polθ 抑制导致神经胶质瘤细胞活力显着下降。它诱导细胞凋亡，伴随着细胞增殖和 DNA 损伤减少。此外，当与 PARP1 或 RAD52 双重抑制 Polθ 时，效果更强，并且添加 TMZ 可进一步增强效果。对正常细胞的影响要小得多，尤其是考虑到细胞活力和 DNA 损伤时。总之，我们想强调的是，与 PARP1 或 RAD52 抑制联合使用的 Polθ 抑制具有杀死神经胶质瘤细胞的巨大潜力，并显示出合成致死效应，同时保留正常星形胶质细胞。
