CFTRinh-172 was identified as a potent and selective blocker of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel. CFTRinh-172 inhibits Cl- current in wild-type, G551D, and G1349D CFTR with Ki value of 0.5μM[1]. 1 and 10µM CFTRinh-172 caused 50% and 90% reduction of the original current in chinese hamster ovary (CHO) cells within 1-2s respectively with IC50 value of 1.1μM, and this inhibition is reversible[2].
In vitro, CFTR-expressing fischer rat thyroid cells incubated with CFTRinh-172 rapid and dose-dependently inhibited short-circuit current with CFTRinh-172 added to the solution bathing the apical cell surface. The average dose inhibition relationships of CFTRinh-172 is with Kd value of 300nM[3]. Human glioblastoma cell line U87 cells pretreated with CFTRinh-172 (5μM) for 30min, and then exposed to Forskolin (50μM) for additional 48h. CFTRinh-172 significantly increased cell viability and cell density, while partially restored inhibitory effects of Forskolin on U87 cell viability and cell density. CFTRinh-172 pretreatment partially attenuated the effects of Forskolin on Ki67 positive rate and significantly increased cell colony formation number[4]. CCRF-CEM, Jurkat and MOLT-4 T-ALL cell line were treated with CFTRinh-172 (5 to 40μM) for 24h or 48h. CFTRinh-172 concentration-dependently inhibited the growth of all three T-ALL cell lines and blocked the cell cycle. CCRF-CEM, JURKAT and MOLT-4 cells treated with 20μM CFTRinh-172 for 24h significantly changed the gene expression involved in various signaling pathways, including the Wnt/TGF-beta signaling pathway, the cell cycle, apoptotic process, cell proliferation, programmed cell death, etc[5].
In vivo, CFTRinh-172 (3mg/kg) was intraperitoneal administrated in E. coli-induced acute lung inflammation mouse models. Inhibition of CFTR by CFTRinh-172 deteriorated E. coli-induced acute lung inflammation. CFTRinh-172 induced deficiency of CFTR promotes migration of monocytes and neutrophils in E. coli pneumonia and peritonitis mouse models[6]. LPS-Induced Acute Lung Injury rat models were administrated with lipoxin A4 (2µM/kg; iv) following CFTRinh-172 treatment. 1.5mL (5mL/kg) of the instillate solution with CFTRinh-172 (1µM) was instilled at a rate of 0.08mL/min via tracheal instillation using a syringe pump. Lipoxin A4 significantly improved histology of rat lungs and inhibited IL-6 and TNF-α in LPS-induced lung injury. CFTRinh-172 abolished the effect of lipoxin A4 on alveolar fluid clearance (AFC)[7].
References:
[1] Taddei A, Folli C, Moran O G, et al. Altered channel gating mechanism for CFTR inhibition by a high-affinity thiazolidinone blocker. FEBS Lett. 2004 Jan 30;558(1-3):52-6.
[2] Kopeikin Z, Sohma Y, Li M, Hwang T C.On the mechanism of CFTR inhibition by a thiazolidinone derivative. J Gen Physiol. 2010 Dec;136(6):659-71.
[3] Ma T, Thiagarajah J R, Yang H, et al. Thiazolidinone CFTR inhibitor identified by high-throughput screening blocks cholera toxin-induced intestinal fluid secretion. J Clin Invest. 2002 Dec;110(11):1651-8.
[4] Zhong X, Chen H Q, Yang X L, et al. CFTR activation suppresses glioblastoma cell proliferation, migration and invasion. Biochem Biophys Res Commun. 2019 Jan 22;508(4):1279-1285
[5] Liu M F, Liao H J, Chen Y, et al. Treatment of human T-cell acute lymphoblastic leukemia cells with CFTR inhibitor CFTRinh-172. Leuk Res. 2019 Nov:86:106225.
[6] Gao Z, Su X. CFTR regulates acute inflammatory responses in macrophages. QJM. 2015 Dec;108(12):951-8.
[7] Yang Y, Cheng Y, Lian Q Q, et al. Contribution of CFTR to alveolar fluid clearance by lipoxin A4 via PI3K/Akt pathway in LPS-induced acute lung injury. Mediators Inflamm. 2013:2013:862628.
CFTRinh-172被鉴定为囊性纤维化跨膜传导调节因子(CFTR)Cl-通道强效的选择性阻断剂。CFTRinh-172对野生型、G551D和G1349D CFTR的Cl-电流具有抑制作用，Ki值为0.5μM[1]。1μM和10μM的CFTRinh-172在1–2s内分别使中华仓鼠卵巢(CHO)细胞原始电流降低50%和90%，IC50值为1.1μM，且该抑制可逆[2]。
体外实验中，表达CFTR的Fischer大鼠甲状腺细胞经CFTRinh-172孵育后，可快速且剂量依赖性地抑制短路电流；CFTRinh-172被添加至细胞培养液中，平均剂量-抑制关系的Kd值为300nM[3]。人胶质母细胞瘤细胞系U87先用CFTRinh-172 （5µM）预处理30min，再用Forskolin（50µM）处理48h。CFTRinh-172显著提高了细胞活力和细胞密度，同时部分恢复了Forskolin对U87细胞活力和细胞密度的抑制作用。CFTRinh-172预处理部分减弱了Forskolin对Ki67阳性率的影响，并显著增加了细胞集落形成数目[4]。CCRF-CEM、Jurkat和MOLT-4 T-ALL细胞系经CFTRinh-172（5–40μM）处理24h或48h。CFTRinh-172呈浓度依赖性地抑制所有三种T-ALL细胞系生长并阻断细胞周期。CCRF-CEM、JURKAT和MOLT-4细胞经20μM CFTRinh-172处理24h后，显著改变涉及多种信号通路(包括Wnt/TGF-β信号通路、细胞周期、凋亡过程、细胞增殖、程序性细胞死亡等)的基因表达[5]。
体内实验中，大肠杆菌诱导的急性肺炎症小鼠模型经腹腔给予CFTRinh-172（3mg/kg），CFTRinh-172抑制CFTR加剧了大肠杆菌诱导的急性肺炎症，CFTRinh-172诱导的CFTR缺失促进了大肠杆菌肺炎和腹膜炎小鼠模型中单核细胞和中性粒细胞的迁移[6]。LPS诱导的急性肺损伤大鼠模型经CFTRinh-172治疗后，再静脉给予脂氧素A4（2µM/kg），通过注射泵以0.08mL/min的速度经气管灌注1.5mL（5mL/kg）含CFTRinh-172（1µM）的灌注液。脂氧素A4显著改善LPS诱导肺损伤大鼠的肺组织学表现并抑制IL-6和TNF-α，CFTRinh-172则消除了脂氧素A4对肺泡液体清除（AFC）的作用[7]。