In the last 15 years, pyridazinone derivatives have acquired extensive attention due to their widespread biological activities and pharmacological applications. Pyridazinones are well known for their anti-microbial, anti-viral, anti-inflammatory, anti-cancer, and cardiovascular activities, among others. In this study, we evaluated the anti-cancer activity of a new pyridazinone derivative and propose it as a potential anti-neoplastic agent in acute promyelocytic leukemia cells. Pyr-1 cytotoxicity was assessed on several human cancer and two non-cancerous cell lines by the DNS assay. Pyr-1 demonstrated potent cytotoxicity against 22 human cancer cell lines, exhibiting the most favorable selective cytotoxicity on leukemia (CEM and HL-60), breast (MDA-MB-231 and MDA-MB-468), and lung (A-549) cancer cell lines, when compared with non-cancerous breast epithelial MCF-10A cells. Analyses of apoptosis/necrosis pathways, reactive oxygen species (ROS) production, mitochondria health, caspase-3 activation, and cell cycle profile were performed via flow cytometry. Both hmox-1 RNA and protein expression levels were evaluated by quantitative real-time PCR and Western blotting assays, respectively. Pyr-1 induced apoptosis in acute promyelocytic leukemia cells as confirmed by phosphatidylserine externalization, mitochondrial depolarization, caspase-3 activation, DNA fragmentation, and disrupted cell cycle progression. Additionally, it was determined that Pyr-1 generates oxidative and proteotoxic stress by provoking the accumulation of ROS, resulting in the overexpression of the stress-related hmox-1 mRNA transcripts and protein and a marked increase in poly-ubiquitinated proteins. Our data demonstrate that Pyr-1 induces cell death via the intrinsic apoptosis pathway by accumulating ROS and by impairing proteasome activity.

中文翻译：

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一种新的哒嗪酮通过凋亡和多泛素化蛋白积累，对人癌细胞具有强力的细胞毒性。

在过去的15年中，哒嗪酮衍生物因其广泛的生物学活性和药理应用而受到广泛关注。吡嗪酮因其抗微生物，抗病毒，抗炎，抗癌和心血管活动而闻名。在这项研究中，我们评估了一种新的哒嗪酮衍生物的抗癌活性，并提出了其作为急性早幼粒细胞白血病细胞中潜在的抗肿瘤药。通过DNS分析评估了Pyr-1对几种人类癌症和两种非癌细胞系的细胞毒性。Pyr-1表现出对22种人类癌细胞的有效细胞毒性，对白血病（CEM和HL-60），乳腺癌（MDA-MB-231和MDA-MB-468）和肺（A-549）表现出最有利的选择性细胞毒性）癌细胞系，与非癌性乳腺癌上皮MCF-10A细胞相比。通过流式细胞仪分析细胞凋亡/坏死途径，活性氧（ROS）产生，线粒体健康，caspase-3活化和细胞周期概况。都hmox-1 RNA和蛋白质表达水平分别通过实时定量PCR和Western blotting分析进行评估。Pyr-1诱导了急性早幼粒细胞白血病细胞的凋亡，这一点已通过磷脂酰丝氨酸外在化，线粒体去极化，caspase-3活化，DNA片段化和破坏的细胞周期进程得到证实。此外，已确定Pyr-1通过激发ROS的积累而产生氧化应激和蛋白毒性应激，从而导致应激相关的hmox-1 mRNA转录本和蛋白质的过表达，以及多泛素化蛋白质的显着增加。我们的数据表明，Pyr-1通过内在的细胞凋亡途径通过积累ROS和削弱蛋白酶体活性来诱导细胞死亡。