ABSTRACT
N 6-methyladenosine (m6A) modification is critical for mRNA splicing, nuclear export, stability and translation. Fat mass and obesity-associated protein (FTO), the first identified m6A demethylase, is critical for cancer progression. Herein, we developed small-molecule inhibitors of FTO by virtual screening, structural optimization, and bioassay. As a result, two FTO inhibitors namely 18077 and 18097 were identified, which can selectively inhibit demethylase activity of FTO. Specifically, 18097 bound to the active site of FTO and then inhibited cell cycle process and migration of cancer cells. In addition, 18097 reprogrammed the epi-transcriptome of breast cancer cells, particularly for genes related to P53 pathway. 18097 increased the abundance of m6A modification of suppressor of cytokine signaling 1 (SOCS1) mRNA, which recruited IGF2BP1 to increase mRNA stability of SOCS1 and subsequently activated the P53 signaling pathway. Further, 18097 suppressed cellular lipogenesis via downregulation of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), and C/EBPβ. Animal studies confirmed that 18097 can significantly suppress in vivo growth and lung colonization of breast cancer cells. Collectively, we identified that FTO can work as a potential drug target and the small-molecule inhibitor 18097 can serve as a potential agent against breast cancer.
ABSTRACT
Objective To study the effect of Sildenafil in the treatment of hypoxemia after operation of cyanotic congenital heart disease.Methods A total of 34 cases with hypoxemia after operation of cyanotic congenital heart disease were collected between January 2009 to January 2015.They took Sildenafil with the dosage of 0.3-0.5 mg/kg every 6 hour.The change of heart rate (HR),systolic blood pressure (SBP),central venous pressure (CVP),pulmonary artery pressure (PAP),arterial partial pressure of oxygen [pa (O2)],arterial partial pressure of carbon dioxide [Pa (CO2)],oxygenation index [pa (O2)/FiO2],peak airway pressure (Ppeak),positive inotropic drug score (PIDS) and the lower bound of liver were observed at 4 time points,including before taking the medicine,after taking the medicine for 1 hour,after taking the medicine 1 day and after the ventilator was removed.Based on the data,the therapeutic effects of Sildenafil were studied.Results All 34 cases were cured.At the time point of 1 hour after taking Sildenafil,PAP,CVP and Ppeak decreased significantly,but pa (O2) and pa (O2)/FiO2 increased significantly (P ＜ 0.05).At the time point of 1 day after taking Sildinafil,SBP increased steadily,but PAP and CVP continued to get lower,and PIDS decreased significantly,while the liver lower bound was significantly reduced (P ＜ 0.05).At the time point of removing the ventilator,pa (O2) reached to (144.12 ± 26.25) mmHg,and hypoxemia was corrected,but PAP was reduced to (37.47 ± 3.77) mmHg,PIDS decreased to (17.56-± 1.94) scores,and heart failure was corrected.Compared with the previous 3 time points,there were statistically significant differences (P ＜ 0.05).Conclusion Sildenafil can highly selectively decrease pulmonary vascular resistance and obviously promote the correction of hypoxemia after operation of cyanotic congenital heart disease.