Design, synthesis, and biological evaluation of piperazine derivatives as pan-PPARs agonists for the treatment of liver fibrosis.

Liver fibrosis is commonly occurred in chronic liver diseases, but there is no approved drug for clinical use. The nuclear receptor peroxisome proliferator-activated receptors (PPARs) could not only regulate metabolic homeostasis but also possess anti-inflammatory and antifibrotic effects, and pan-PPARs agonist was considered as a potential anti-liver fibrosis agent. In this study, a series of novel piperazine pan-PPARs agonists were developed, and the preferred compound 12 displayed potent and well-balanced pan-PPARs agonistic activity. Moreover, compound 12 could dose-dependently stimulate the PPARs target genes expression and showed high selectivity over other related nuclear receptors. Importantly, compound 12 exhibited excellent pharmacokinetic profiles and good anti-liver fibrosis effects in vivo. Collectively, compound 12 holds promise for developing an anti-liver fibrosis agent.

Discovery of Novel PD-L1 Small-Molecular Inhibitors with Potent In Vivo Anti-tumor Immune Activity.

Programmed death-ligand 1 (PD-L1) has surfaced as a promising therapeutic target for various cancers due to its pivotal role in facilitating tumor immune evasion. Herein, we report a series of novel small-molecule PD-L1 inhibitors exhibiting remarkable inhibitory activity against the PD-1/PD-L1 interaction (X18: IC50 = 1.3 nM) and reinstating the suppressive effect of PD-L1 on T cells (X18: EC50 = 152.8 nM). Crystallographic studies revealed the binding mode of X18 and PD-L1. Through a rational prodrug design approach, we have successfully optimized the oral pharmacokinetic properties of X22, effectively addressing the poor oral pharmacokinetic profile of PD-L1 small-molecule inhibitors. Notably, X22 demonstrated significant antitumor efficacy in murine models of MC38 and CT26 colon cancer through the upregulation of tumor infiltration and cytotoxicity of CD8+ T cells partially. These findings offer promising prospects for the advancement of PD-L1 inhibitors as innovative agents in cancer immunotherapy.

Discovery of the First Subnanomolar PPARα/δ Dual Agonist for the Treatment of Cholestatic Liver Diseases.

Peroxisome proliferator-activator receptors α/δ (PPARα/δ) are considered as potential drug targets for cholestatic liver diseases (CLD) via ameliorating hepatic cholestasis, inflammation, and fibrosis. In this work, we developed a series of hydantoin derivatives as potent PPARα/δ dual agonists. Representative compound V1 exhibited PPARα/δ dual agonistic activity at the subnanomolar level (PPARα EC50 = 0.7 nM; PPARδ EC50 = 0.4 nM) and showed excellent selectivity over other related nuclear receptors. The crystal structure revealed the binding mode of V1 and PPARδ at 2.1 Å resolution. Importantly, V1 demonstrated excellent pharmacokinetic (PK) properties and a good safety profile. Notably, V1 showed potent anti-CLD and antifibrotic effects in preclinical models at very low doses (0.03 and 0.1 mg/kg). Collectively, this work provides a promising drug candidate for treating CLD and other hepatic fibrosis diseases.

Discovery of novel AdipoRon analogues as potent anti-inflammatory agents against nonalcoholic steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a rising public health burden, and there is a lack of effective therapeutic drugs in clinical practice. Sustained hepatic inflammation is considered as the key histopathological feature and dangerous fact for NASH. Different causes vary from one NASH patient to another, while sustained hepatic inflammation affects all NASH patients. AdipoRon is the first small-molecule AdipoR agonist, exerting antidiabetic and anti-inflammatory effect. In order to find novel AdipoRon analogues with more potent anti-inflammatory activity, we designed, synthesized and biologically evaluated 32 analogues. Among them, Q7 exerted potent anti-inflammatory activity and less cytotoxicity. Q7 could dose-dependently stimulate the increasing of AMPK phosphorylation, the widely recognized downstream effector of AdipoR1 activation. In NASH model mice, Q7 showed significant anti-inflammatory, anti-fibrotic and lipid-lowering effect in mice liver, and was superior to AdipoRon. Together, Q7 holds promise for developing anti-inflammatory and anti-NASH agents.

Qi-Tai-Suan, an oleanolic acid derivative, ameliorates ischemic heart failure via suppression of cardiac apoptosis, inflammation and fibrosis.

Although anti-thrombotic therapy has been successful for prevention of deaths from acute myocardial infarction (MI), by far, there are few preventive and therapeutic options for ischemic heart failure (IHF) after MI. Qi-Tai-Suan (QTS) is an oleanolic acid (OA) derivative which once underwent a clinical trial for treating hepatitis. In this study, we investigated the potential cardioprotective effect of QTS on IHF. IHF mouse model was constructed by coronary artery ligation in male C57BL/6J mice, and the protective effects of QTS on IHF were examined by echocardiography measurement, histological and TUNEL analysis, etc. We found that QTS exhibited promising cardioprotective effect on IHF. QTS treatment significantly improved cardiac function of IHF mice and the symptoms of heart failure. Notably, QTS had much better oral bioavailability (F = 41.91%) in mice than its parent drug OA, and took effects mainly as its original form. Mechanistically, QTS ameliorated ischemic heart failure likely through suppression of cardiac apoptosis, inflammation and fibrosis. Taken together, QTS holds great promise as a preventive and therapeutic agent for ischemic heart failure and related diseases.

Design, Synthesis, and Biological Evaluation of Triazolone Derivatives as Potent PPARα/δ Dual Agonists for the Treatment of Nonalcoholic Steatohepatitis.

Peroxisome proliferator-activator receptors α/δ (PPARα/δ) are regarded as potential therapeutic targets for nonalcoholic steatohepatitis (NASH). However, PPARα/δ dual agonist GFT-505 exhibited poor anti-NASH effects in a phase III clinical trial, probably due to its weak PPARα/δ agonistic activity and poor metabolic stability. Other reported PPARα/δ dual agonists either exhibited limited potency or had unbalanced PPARα/δ agonistic activity. Herein, we report a series of novel triazolone derivatives as PPARα/δ dual agonists. Among them, compound H11 exhibited potent and well-balanced PPARα/δ agonistic activity (PPARα EC50 = 7.0 nM; PPARδ EC50 = 8.4 nM) and a high selectivity over PPARγ (PPARγ EC50 = 1316.1 nM) in PPAR transactivation assays. The crystal structure of PPARδ in complex with H11 revealed a unique PPARδ-agonist interaction. H11, which had excellent PK properties and a good safety profile, showed potent in vivo anti-NASH effects in preclinical models. Together, H11 holds a great promise for treating NASH or other inflammatory and fibrotic diseases.

Discovery of Novel Peroxisome Proliferator-Activated Receptor α (PPARα) Agonists by Virtual Screening and Biological Evaluation.

Nonalcoholic steatohepatitis (NASH) is one of the important causes of cirrhosis and hepatocellular carcinoma worldwide. PPARα is highly expressed in the liver and plays a critical role in hepatic lipid metabolism. Our analysis of the gene expression profiles in the liver of humanized mice treated with a PPARα agonist and NASH patients suggested that PPARα might be a potential target for NASH therapy. This promoted us to find novel PPARα agonists. The results of virtual screening and biological evaluation identified compound A-4 as a selective PPARα agonist. It significantly regulated the target genes of PPARα involved in fatty acid metabolism and inflammation, exhibiting cellular anti-inflammatory activity. The key residues involved in the binding between PPARα ligand-binding domain (LBD) and compound A-4 were revealed by molecular dynamics (MD) simulation and further experimentally validated by the mutation study. Together, compound A-4 was well characterized as a novel lead compound for developing potent and selective PPARα agonists.

Synergistic antitumor activity of artesunate and HDAC inhibitors through elevating heme synthesis via synergistic upregulation of ALAS1 expression.

Artemisinin and its derivatives (ARTs) were reported to display heme-dependent antitumor activity. On the other hand, histone deacetylase inhibitors (HDACi) were known to be able to promote heme synthesis in erythroid cells. Nevertheless, the effect of HDACi on heme homeostasis in non-erythrocytes remains unknown. We envisioned that the combination of HDACi and artesunate (ARS) might have synergistic antitumor activity through modulating heme synthesis. In vitro studies revealed that combination of ARS and HDACi exerted synergistic tumor inhibition by inducing cell death. Moreover, this combination exhibited more effective antitumor activity than either ARS or HDACi monotherapy in xenograft models without apparent toxicity. Importantly, mechanistic studies revealed that HDACi coordinated with ARS to increase 5-aminolevulinate synthase (ALAS1) expression, and subsequent heme production, leading to enhanced cytotoxicity of ARS. Notably, knocking down ALAS1 significantly blunted the synergistic effect of ARS and HDACi on tumor inhibition, indicating a critical role of ALAS1 upregulation in mediating ARS cytotoxicity. Collectively, our study revealed the mechanism of synergistic antitumor action of ARS and HDACi. This finding indicates that modulation of heme synthesis pathway by the combination based on ARTs and other heme synthesis modulators represents a promising therapeutic approach to solid tumors.

THAP7 promotes cell proliferation by regulating the G1/S phase transition via epigenetically silencing p21 in lung adenocarcinoma.

PURPOSE: Lung adenocarcinoma (LUAD) is one of the most common cancers worldwide. The THanatos-Associated Proteins (THAP) family plays an essential role in multiple cancers. However, the role of THAP7 in cancers has remained elusive. METHODS: THAP7 expression status in LUAD tissues was analysed by using the Oncomine database and qRT-PCR, and its expression level in LUAD cell lines was detected by qRT-PCR and Western blotting. The role of THAP7 in LUAD cells was determined by proliferation, colony formation, and cell cycle analyses. In vivo role of THAP7 was studied on xenograft models. Luciferase reporter assays and chromatin immunoprecipitation (ChIP) were used to determine the activity and acetylation of the p21 promoter. RESULTS: THAP7 expression was increased in LUAD tissues and cell lines. Moreover, the high expression of THAP7 was correlated with poor prognosis. The overexpression of THAP7 accelerated the G1/S phase transition and promoted tumour growth both in vitro and in vivo. A mechanistic study revealed that THAP7 reduced the acetylation of histone H3 on the p21 promoter to suppress p21 transcription. CONCLUSION: For the first time, we demonstrated the function of THAP7 in LUAD, and our findings suggested that THAP7 may be a potential molecular therapy target in LUAD.

Synthesis and anti-cancer activity of ND-646 and its derivatives as acetyl-CoA carboxylase 1 inhibitors.

Acetyl-coA carboxylase 1 (ACC1) is the first and rate-limiting enzyme in the de novo fatty acid synthesis (FASyn) pathway. In this study, through public database analysis and clinic sample test, we for the first time verified that ACC1 mRNA is overexpressed in non-small-cell lung cancer (NSCLC), which is accompanied by reduced DNA methylation at CpG island S shore of ACC1. Our study further demonstrated that higher ACC1 levels are associated with poor prognosis in NSCLC patients. Besides, we developed a novel synthetic route for preparation of a known ACC inhibitor ND-646, synthesized a series of its derivatives and evaluated their activity against the enzyme ACC1 and the A549 cell. As results, most of the tested compounds showed potent ACC1 inhibitory activity with IC50 values 3-10 nM. Among them, compounds A2, A7 and A9 displayed strong cancer inhibitory activity with IC50 values 9-17 nM by impairing cell growth and inducing cell death. Preliminary SAR analysis clearly suggested that (R)-configuration and amide group were vital to ACC1 and A549 inhibition, since compound (S)-A1 (the enantiomer of ND-646) had poor activity of ACC1 inhibition and the carboxylic acid ND-630 almost lost anticancer effect on A549 cells. Collectively, these findings indicate that ACC1 is a potential biomarker and target for non-small-cell lung cancer, and ND-646 and its derivatives as ACC1 inhibitors deserve further study for treatment of NSCLC.

Strategies of laparoscopic thyroidectomy for treatment of substernal goiter via areola approach.

BACKGROUND: This study was aimed at exploring the feasibility and strategies of laparoscopic thyroidectomy for treatment of substernal goiter via areola approach. METHODS: A retrospective analysis was conducted to investigate 15 cases of laparoscopic resection of substernal goiter via the areola approach (laparoscopic group) and 12 cases of open resection of substernal goiter via low-neck collar cervical approach (open group) that was completed between December 2012 and December 2014. Operative time, estimated blood loss, postoperative hospitalization and postoperative complication were compared. Follow-up data were assessed, and the mean duration of follow-up was 24.5 ± 7.5 months. RESULTS: The surgery was successfully completed in 14 cases, and 1 case was intraoperatively converted to open surgery. All the procedures were successfully completed in the open group. There was no difference in the mean distance from the inferior border of the excised substernal mass to the sternal notch, operation time, intraoperative estimated blood loss, postoperative hospital stay or the drainage tubes removed. Five cases had transient hypocalcemia after surgery in the laparoscopic group, while 1 case in the open group. There were no cases of hoarseness, dysphagia, lymphatic leakage, dyspnea and death in the two groups. And there were no recurrent cases in the follow-up. CONCLUSION: Laparoscopic thyroidectomy for the treatment of selected substernal goiter via the areola approach is feasible. Preoperative B-ultrasound and 3D-CT scan reconstruction help to select cases and formulate surgical strategies, and the way that the thyroid is suspended using silk threads intraoperatively can reduce surgical difficulties and risks of intraoperative conversion to open surgery.

Endoscopic thyroidectomy via areola approach: summary of 1,250 cases in a single institution.

BACKGROUND: The aim of this study was to evaluate the effect and cosmetic results of endoscopic thyroidectomy (ETE) via the areola approach for patients with thyroid diseases. METHODS: A total of 1,250 patients with thyroid diseases underwent ETE via the areola approach between April 2005 and January 2011. Of these, 898 were benign goiters, 260 were Graves' disease, 28 were secondary hyperthyroidism, and 64 were papillary carcinomas. RESULTS: The surgery was successfully completed in 1,249 cases, and 1 case was converted to open surgery. The mean operation time, estimated blood loss, and hospital stay after surgery for patients with a goiter, hyperthyroidism, and papillary carcinoma were 94.4 min, 15.2 ml, 5.0 days, 97.9 min, 16.1 ml, 5.5 days, and 134.3 min, 18.6 ml, 6.4 days, respectively. Complications included 4 cases of postoperative bleeding, 1 case of transection of the recurrent laryngeal nerve (RLN) on one side, 7 cases of temporary RLN injury, 34 cases of transient hypocalcemia, 5 cases of skin bruising on the chest wall, and 1 case of subcutaneous infection in the neck. At 4.6-year (2.5-8 years) follow-up of 1,185 (94.8 %) patients, 3 patients with Graves' disease had recurrence of hyperthyroidism, and 4 patients with nodular goiter had recurrence of small nodules. Four patients had discomfort on swallowing, 4 patients had an abnormal sensation of skin traction on the neck and the chest, and 1 patient with scar diathesis had mild scar hyperplasia. A total of 876 patients were satisfied, 4 equivocal, and 0 unsatisfied with the cosmetic results. CONCLUSION: ETE via the areola approach for patients with benign goiters, Graves' disease, secondary hyperthyroidism, and papillary carcinomas without metastasis to lateral cervical lymph nodes is an effective and safe procedure with excellent cosmetic results.