Inhibition of phosphatidylcholine-specific phospholipase C (PC-PLC) has previously been shown to be a potential target for novel cancer therapeutics. One downstream consequence of PC-PLC activity is the activation of NF-κB, a nuclear transcription factor responsible for transcribing genes related to oncogenic traits, such as proliferation, angiogenesis, metastasis, and cancer cell survival. Another biological pathway linked to NF-κB is the exogenous delivery of nitric oxide (NO), which decreases NF-κB activity through an apparent negative-feedback loop. In this study, we designed and synthesised 13 novel NO-releasing derivatives of our previously reported class of PC-PLC inhibitors, 2-morpholinobenzoic acids. These molecules contained a secondary benzylamine group, which was readily nitrosylated and subsequently confirmed to release NO in vitro using a DAF-FM fluorescence-based assay. It was then discovered that these NO-releasing derivatives possessed significantly improved anti-proliferative activity in both MDA-MB-231 and HCT116 cancer cell lines compared to their non-nitrosylated parent compounds. These results confirmed that the inclusion of an exogenous NO-releasing functional group onto a known PC-PLC inhibitor enhances anti-proliferative activity and that this relationship can be exploited in order to further improve the anti-proliferative activity of current/future PC-PLC inhibitors.
磷脂酰胆碱特异性磷脂酶C(PC-PLC)的抑制已被证明是新型癌症治疗的潜在靶点之一。PC-PLC活性的一个下游结果是激活NF-κB,这是一个核转录因子,负责转录与致癌特征相关的基因,如增殖、血管生成、转移和癌细胞存活。与NF-κB相关的另一个生物途径是外源性一氧化氮(NO)的传递,通过明显的负反馈环路降低NF-κB的活性。在这项研究中,我们设计并合成了13种新型NO释放衍生物,这些衍生物属于我们先前报道的PC-PLC抑制剂类别——2-吗啉基苯甲酸。这些分子含有一个次苯胺基团,可以轻松地被亚硝化,随后通过基于DAF-FM荧光的体外实验确认释放NO。随后发现,与非亚硝化的母体化合物相比,这些NO释放衍生物在MDA-MB-231和HCT116癌细胞系中显著改善了抗增殖活性。这些结果证实,将外源性NO释放功能基团引入已知的PC-PLC抑制剂中可以增强抗增殖活性,并且可以利用这种关系进一步改善当前/未来的PC-PLC抑制剂的抗增殖活性。