背景:以前的研究报道cGMP特异性PDE5同工酶在结肠腺瘤和腺癌中过度表达,对结肠癌细胞增殖至关重要,而PDE5选择性抑制剂(例如,西地那非)已被报道具有癌症化学预防活性。
目的:本研究旨在确定一种新型PDE5抑制剂的抗癌活性,RF26,利用结直肠癌(CRC)细胞和PDE5在CRC肿瘤体内生长中的作用。
目的:本研究的目的是表征新型塞来昔布衍生物的抗癌活性,在先前报道的CRC细胞中,RF26缺乏COX-2抑制,但具有有效的PDE5抑制活性。
方法:使用人CRC细胞系研究RF26的抗癌活性。它对细胞内cGMP水平的影响,cGMP依赖性蛋白激酶(PKG)活性,β-连环蛋白水平,TCF/LEF转录活性,细胞周期分布,并测量细胞凋亡。CRISPR/cas9PDE5敲除技术用于确定PDE5是否介导RF26的抗癌活性并验证PDE5作为癌症靶标。
结果:RF26在抑制CRC细胞生长方面明显比塞来昔布和西地那非更有效,并且在增加细胞内cGMP水平和激活PKG信号传导的浓度下有效。RF26在相同浓度范围内抑制β-catenin水平和TCF/LEF转录活性并诱导G1细胞周期停滞和凋亡。CRISPR/cas9PDE5敲除CRC细胞对RF26的敏感性降低,增殖速度比亲本细胞慢,并且未能在小鼠中建立肿瘤。
结论:需要进一步评估RF26对癌症的预防或治疗以及研究PDE5在肿瘤发生中的作用。
BACKGROUND: Previous studies have reported that the cGMP-specific PDE5 isozyme is overexpressed in colon adenomas and adenocarcinomas and essential for colon cancer cell proliferation, while PDE5 selective inhibitors (e.g., sildenafil) have been reported to have cancer chemopreventive activity.
OBJECTIVE: This study aimed to determine the anticancer activity of a novel PDE5 inhibitor, RF26, using colorectal cancer (CRC) cells and the role of PDE5 in CRC tumor growth in vivo.
OBJECTIVE: The objective of this study was to characterize the anticancer activity of a novel celecoxib derivative, RF26, in CRC cells previously reported to lack COX-2 inhibition but have potent PDE5 inhibitory activity.
METHODS: Anticancer activity of RF26 was studied using human CRC cell lines. Its effects on intracellular cGMP levels, cGMP-dependent protein kinase (PKG) activity, β-catenin levels, TCF/LEF transcriptional activity, cell cycle distribution, and apoptosis were measured. CRISPR/cas9 PDE5 knockout techniques were used to determine if PDE5 mediates the anticancer activity of RF26 and validate PDE5 as a cancer target.
RESULTS: RF26 was appreciably more potent than celecoxib and sildenafil to suppress CRC cell growth and was effective at concentrations that increased intracellular cGMP levels and activated PKG signaling. RF26 suppressed β-catenin levels and TCF/LEF transcriptional activity and induced G1 cell cycle arrest and apoptosis within the same concentration range. CRISPR/cas9 PDE5 knockout CRC cells displayed reduced sensitivity to RF26, proliferated slower than parental cells, and failed to establish tumors in mice.
CONCLUSIONS: Further evaluation of RF26 for the prevention or treatment of cancer and studying the role of PDE5 in tumorigenesis are warranted.