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Morphinan antagonists, which block opioid effects at mu-opioid receptors, have been studied for their analgesic potential. Previous studies have suggested that these antagonists elicit analgesia with fewer adverse effects in the presence of the mutant mu-opioid receptor (MOR; S196A). However, introducing a mutant receptor for medical applications represents significant challenges. We hypothesize that binding a chemical compound to the MOR may elicit a comparable effect to the S196A mutation. Through high-throughput screening and structure-activity relationship studies, we identified a modulator, 4-(2-(4-fluorophenyl)-4-oxothiazolidin-3-yl)-3-methylbenzoic acid (BPRMU191), which confers agonistic properties to small-molecule morphinan antagonists, which induce G protein-dependent MOR activation. Co-application of BPRMU191 and morphinan antagonists resulted in MOR-dependent analgesia with diminished side effects, including gastrointestinal dysfunction, antinociceptive tolerance, and physical and psychological dependence. Combining BPRMU191 and morphinan antagonists could serve as a potential therapeutic strategy for severe pain with reduced adverse effects and provide an avenue for studying G protein-coupled receptor modulation., Competing Interests: Declaration of interests S.-H.U., S.-H.Y., S.-Y.L., H.H.L., and C.S. have a granted patent (no. US10544113 B2) covering BPRMU191., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Aurora kinase inhibitors, such as alisertib, can destabilize MYC-family oncoproteins and have demonstrated compelling antitumor efficacy. In this study, we report 6K465, a novel pyrimidine-based Aurora A inhibitor, that reduces levels of c-MYC and N-MYC oncoproteins more potently than alisertib. In an analysis of the antiproliferative effect of 6K465, the sensitivities of small cell lung cancer (SCLC) and breast cancer cell lines to 6K465 were strongly associated with the protein levels of c-MYC and/or N-MYC. We also report DBPR728, an acyl-based prodrug of 6K465 bearing fewer hydrogen-bond donors, that exhibited 10-fold improved oral bioavailability. DBPR728 induced durable tumor regression of c-MYC- and/or N-MYC-overexpressing xenografts including SCLC, triple-negative breast cancer, hepatocellular carcinoma, and medulloblastoma using a 5-on-2-off or once-a-week dosing regimen on a 21-day cycle. A single oral dose of DBPR728 at 300 mg/kg induced c-MYC reduction and cell apoptosis in the tumor xenografts for more than 7 days. The inhibitory effect of DBPR728 at a reduced dosing frequency was attributed to its uniquely high tumor/plasma ratio (3.6-fold within 7 days) and the long tumor half-life of active moiety 6K465. Furthermore, DBPR728 was found to synergize with the mTOR inhibitor everolimus to suppress c-MYC- or N-MYC-driven SCLC. Collectively, these results suggest DBPR728 has the potential to treat cancers overexpressing c-MYC and/or N-MYC., (©2024 American Association for Cancer Research.)

Fucoidans are a class of long chain sulfated polysaccharides and have multiple biological functions. Herein, four natural fucoidans extracted from Fucus vesiculosus, F. serratus, Laminaria japonica and Undaria pinnatifida, were tested for their HCoV-OC43 inhibition and found to demonstrate EC 50 values ranging from 0.15 to 0.61 µg/mL. That from U. pinnatifida exhibited the most potent anti-HCoV-OC43 activity with an EC 50 value of 0.15 ± 0.02 µg/mL, a potency largely independent of its sulfate content. Comparison of the gene expression profiles of fucoidan-treated and untreated cells infected with HCoV-OC43 revealed that fucoidan treatment effectively diminished HCoV-OC43 gene expressions associated with induced chemokines, cytokines and viral activities. Further studies using a highly fucoidan-resistant HCoV-OC43 determined that fucoidan inhibited HCoV-OC43 infection via interfering with viral entry and led to the identification of the specific site on the N-terminal region of spike protein, that located adjacent to the host cell receptor binding domain, targeted by the virus. Furthermore, in a SARS-CoV-2 pseudovirus neutralization assay, fucoidan also blocked SARS-CoV-2 entry. In vitro and in vivo, fucoidan decreased SARS-CoV-2 viral loads and inhibited viral infection in Calu-3 or Vero E6 cells and SARS-CoV-2 infected hamsters, respectively. Fucoidan was also found to inhibit furin activity, and reported furin inhibitors were found to inhibit viral infection by wild type HCoV-OC43 or SARS-CoV-2. Accordingly, we conclude that fucoidans inhibit coronaviral infection by targeting viral spike protein and host cell furin to interfere with viral entry., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The development of orally bioavailable, furanopyrimidine-based double-mutant (L858R/T790M) EGFR inhibitors is described. First, selectivity for mutant EGFR was accomplished by replacing the ( S )-2-phenylglycinol moiety of 12 with either an ethanol or an alkyl substituent. Then, the cellular potency and physicochemical properties were optimized through insights from molecular modeling studies by implanting various solubilizing groups in phenyl rings A and B. Optimized lead 52 shows 8-fold selective inhibition of H1975 (EGFR L858R/T790M overexpressing) cancer cells over A431 (EGFR WT overexpressing) cancer cells; western blot analysis further confirmed EGFR mutant-selective target modulation inside the cancer cells by 52 . Notably, 52 displayed in vivo antitumor effects in two different mouse xenograft models (BaF3 transfected with mutant EGFR and H1975 tumors) with TGI = 74.9 and 97.5% after oral administration ( F = 27%), respectively. With an extraordinary kinome selectivity ( S (10) score of 0.017), 52 undergoes detailed preclinical development.

The major challenge in COVID-19 vaccine effectiveness is immune escape by SARS-CoV-2 variants. To overcome this, an Omicron-specific messenger RNA (mRNA) vaccine was designed. The extracellular domain of the spike of the Omicron variant was fused with a modified GCN4 trimerization domain with low immunogenicity (TSomi). After immunization with TSomi mRNA in hamsters, animals were challenged with SARS-CoV-2 virus. The raised nonneutralizing antibodies or cytokine secretion responses can recognize both Wuhan S and Omicron S. However, the raised antibodies neutralized SARS-CoV-2 Omicron virus infection but failed to generate Wuhan virus neutralizing antibodies. Surprisingly, TSomi mRNA immunization protected animals from Wuhan virus challenge. These data indicated that non-neutralizing antibodies or cellular immunity may play a more important role in vaccine-induced protection than previously believed. Next-generation COVID-19 vaccines using the Omicron S antigen may provide sufficient protection against ancestral or current SARS-CoV-2 variants., (© 2022 The Authors. Journal of Medical Virology published by Wiley Periodicals LLC.)

Currently, there is a significant unmet need for novel analgesics with fewer side effects. In this study, we carried out structural modification of a hit compound previously identified in an artificial-intelligence (AI) virtual screening and discovered the potent analgesic, benzo[b]thiophene-2-carboxamide analog (compound 25) with new structural scaffold. We investigated the signaling pathways of opioid receptors mediated by compound 25, and found this racemic compound activated mu-opioid receptor through the cyclic adenosine monophosphate (cAMP) and β-arrestin-2-mediated pathways with strong potency and efficacy, and accompanying nociceptin-orphanin FQ opioid peptide and delta-opioid receptors through the cAMP pathway with weak potencies. Compound 25 elicited potent antinociception in thermal-stimulated pain (ED 50 value of 127.1 ± 34.65 μg/kg) and inflammatory-induced allodynia models with less gastrointestinal transit inhibition and antinociceptive tolerance than morphine. Overall, this study revealed a novel analgesic with reduced risks of side effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

(1) Destabilization of microtubule dynamics is a primary strategy to inhibit fast growing tumor cells. The low cytotoxic derivative of microtubule inhibitor D-24851, named BPR0C261 exhibits antitumor activity via oral administration. In this study, we investigated if BPR0C261 could modulate the radiation response of human non-small cell lung cancer (NSCLC) cells with or without p53 expression. (2) Different doses of BPR0C261 was used to treat human NSCLC A549 (p53+/+) cells and H1299 (p53-/-) cells. The cytotoxicity, radiosensitivity, cell cycle distribution, DNA damage, and protein expression were evaluated using an MTT assay, a colony formation assay, flow cytometry, a comet assay, and an immunoblotting analysis, respectively. (3) BPR0C261 showed a dose-dependent cytotoxicity on A549 cells and H1299 cells with IC 50 at 0.38 μM and 0.86 μM, respectively. BPR0C261 also induced maximum G 2 /M phase arrest and apoptosis in both cell lines after 24 h of treatment with a dose-dependent manner. The colony formation analysis demonstrated that a combination of low concentration of BPR0C261 and X-rays caused a synergistic radiosensitizing effect on NSCLC cells. Additionally, we found that a low concentration of BPR0C261 was sufficient to induce DNA damage in these cells, and it increased the level of DNA damage induced by a fractionation radiation dose (2 Gy) of conventional radiotherapy. Furthermore, the p53 protein level of A549 cell line was upregulated by BPR0C261. On the other hand, the expression of PTEN tumor suppressor was found to be upregulated in H1299 cells but not in A549 cells under the same treatment. Although radiation could not induce PTEN in H1299 cells, a combination of low concentration of BPR0C261 and radiation could reverse this situation. (4) BPR0C261 exhibits specific anticancer effects on NSCLC cells by the enhancement of DNA damage and radiosensitivity with p53-dependent and p53-independent/PTEN-dependent manners. The combination of radiation and BPR0C261 may provide an important strategy for the improvement of radiotherapeutic treatment.

Background: Encapsulating peritoneal sclerosis (EPS) is a catastrophic complication of peritoneal dialysis (PD) with high mortality. Our aim is to develop a novel noninvasive microRNA (miRNA) test for EPS., Methods: We collected 142 PD effluents (EPS: 62 and non-EPS:80). MiRNA profiles of PD effluents were examined by a high-throughput real-time polymerase chain reaction (PCR) array to first screen. Candidate miRNAs were verified by single real-time PCR. The model for EPS prediction was evaluated by multiple logistic regression and machine learning., Results: Seven candidate miRNAs were identified from the screening of PCR-array of 377 miRNAs. The top five area under the curve (AUC) values with 5 miRNA-ratios were selected using 127 samples (EPS: 56 vs non-EPS: 71) to produce a receiver operating characteristic curve. After considering clinical characteristics and 5 miRNA-ratios, the accuracies of the machine learning model of Random Forest and multiple logistic regression were boosted to AUC 0.97 and 0.99, respectively. Furthermore, the pathway analysis of miRNA associated targeting genes and miRNA-compound interaction network revealed that these five miRNAs played the roles in TGF-β signaling pathway., Conclusion: The model-based miRNA expressions in PD effluents may help determine the probability of EPS and provide further therapeutic opinion for EPS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

We identified, via high-throughput screening using a FLIPR® calcium assay, compound 1, which incorporated a dihydroquinolinyl-2-oxoethylsulfanyl-(1H,5H)-pyrimidinedione core and activated the μ-opioid receptor (MOR) in the presence of naloxone or naltrexone. A structure-activity relationship study of the analogs of 1 led to the design of compound 21, which activated MOR in the presence of naloxone with an EC 50 of 3.3 ± 0.2 μM. MOR activation by the compound 21-antagonist pair was antagonist-dependent. Compound 21 did not affect the potency of the orthosteric agonist, morphine, toward MOR, indicating that it affected the function of MOR antagonists rather than that of the agonists. Computer modeling of the compound 21-MOR-naloxone complex revealed major interactions between compound 21 and MOR, including hydrogen bonding with Ser196, π-π stacking with Tyr149, and sulfur-aromatic interaction with Trp192. This study may pave the way for developing agents capable of safe and effective MOR modulation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Ligand-targeting drug delivery systems have made significant strides for disease treatments with numerous clinical approvals in this era of precision medicine. Herein, we report a class of small molecule-based immune checkpoint-targeting maytansinoid conjugates. From the ligand targeting ability, pharmacokinetics profiling, in vivo anti-pancreatic cancer, triple-negative breast cancer, and sorafenib-resistant liver cancer efficacies with quantitative mRNA analysis of treated-tumor tissues, we demonstrated that conjugate 40a not only induced lasting regression of tumor growth, but it also rejuvenated the once immunosuppressive tumor microenvironment to an "inflamed hot tumor" with significant elevation of gene expressions that were not accessible in the vehicle-treated tumor. In turn, the immune checkpoint-targeting small molecule drug conjugate from this work represents a new pharmacodelivery strategy that can be expanded with combination therapy with existing immune-oncology treatment options.

CXCR4 antagonists have been claimed to reduce mortality after myocardial infarction in myocardial infarction (MI) animals, presumably due to suppressing inflammatory responses caused by myocardial ischemia-reperfusion injury, thus, subsequently facilitating tissue repair and cardiac function recovery. This study aims to determine whether a newly designed CXCR4 antagonist DBPR807 could exert better vascular-protective effects than other clinical counterparts (e.g., AMD3100) to alleviate cardiac damage further exacerbated by reperfusion. Consequently, we find that instead of traditional continuous treatment or multiple-dose treatment at different intervals of time, a single-dose treatment of DBPR807 before reperfusion in MI animals could attenuate inflammation via protecting oxidative stress damage and preserve vascular/capillary density and integrity via mobilizing endothelial progenitor cells, leading to a desirable fibrosis reduction and recovery of cardiac function, as evaluated with the LVEF (left ventricular ejection fraction) in infarcted hearts in rats and mini-pigs, respectively. Thus, it is highly suggested that CXCR4 antagonists should be given at a single high dose prior to reperfusion to provide the maximal cardiac functional improvement. Based on its favorable efficacy and safety profiles indicated in tested animals, DBPR807 has a great potential to serve as an adjunctive medicine for percutaneous coronary intervention (PCI) therapies in acute MI patients.

Ciclesonide is an inhaled corticosteroid used to treat asthma and has been repurposed as a treatment for mildly ill COVID-19 patients, but its precise mechanism of action is unclear. Herein, we report that ciclesonide blocks the coronavirus-induced production of the cytokines IL-6, IL-8, and MCP-1 by increasing IκBα protein levels and significantly decreasing p65 nuclear translocation. Furthermore, we found that the combination of ciclesonide and dbq33b, a potent tylophorine-based coronavirus inhibitor that affects coronavirus-induced NF-κB activation a little, additively and synergistically decreased coronavirus-induced IL-6, IL-8, and MCP-1 cytokine levels, and synergistically inhibited the replication of both HCoV-OC43 and SARS-CoV-2. Collectively, the combination of ciclesonide and dbq33b merits consideration as a treatment for COVID-19 patients who may otherwise be overwhelmed by high viral loads and an NF-κB-mediated cytokine storm.

Ligand-targeting drug conjugates are a class of clinically validated biopharmaceutical drugs constructed by conjugating cytotoxic drugs with specific disease antigen targeting ligands through appropriate linkers. The integrated linker-drug motif embedded within such a system can prevent the premature release during systemic circulation, thereby allowing the targeting ligand to engage with the disease antigen and selective accumulation. We have designed and synthesized new thioester-linked maytansinoid conjugates. By performing in vitro cytotoxicity, targeting ligand binding assay, and in vivo pharmacokinetic studies, we investigated the utility of this new linker-drug moiety in the small molecule drug conjugate (SMDC) system. In particular, we conjugated the thioester-linked maytansinoids to the phosphatidylserine-targeting small molecule zinc dipicolylamine and showed that Zn8_DM1 induced tumor regression in the HCC1806 triple-negative breast cancer xenograft model. Moreover, in a spontaneous sorafenib-resistant liver cancer model, Zn8_DM1 exhibited potent antitumor growth efficacy. From quantitative mRNA analysis of Zn8_DM1 treated-tumor tissues, we observed the elevation of gene expressions associated with a "hot inflamed tumor" state. With the identification and validation of a plethora of cancer-associated antigens in the "omics" era, this work provided the insight that antibody- or small molecule-based targeting ligands can be conjugated similarly to generate new ligand-targeting drug conjugates.

An effective COVID-19 vaccine against broad SARS-CoV-2 variants is still an unmet need. In the study, the vesicular stomatitis virus (VSV)-based vector was used to express the SARS-CoV-2 Spike protein to identify better vaccine designs. The replication-competent of the recombinant VSV-spike virus with C-terminal 19 amino acid truncation (SΔ19 Rep) was generated. A single dose of SΔ19 Rep intranasal vaccination is sufficient to induce protective immunity against SARS-CoV-2 infection in hamsters. All the clones isolated from the SΔ19 Rep virus contained R682G mutation located at the Furin cleavage site. An additional S813Y mutation close to the TMPRSS2 cleavage site was identified in some clones. The enzymatic processing of S protein was blocked by these mutations. The vaccination of the R682G-S813Y virus produced a high antibody response against S protein and a robust S protein-specific CD8 + T cell response. The vaccinated animals were protected from the lethal SARS-CoV-2 (delta variant) challenge. The S antigen with resistance to enzymatic processes by Furin and TMPRSS2 will provide better immunogenicity for vaccine design., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lin, Tien, Kuo, Lin, Tsai, Chen, Tsai, Su, Pathak, Yang, Yu, Chuang, Wu, Tsai, Dai, Liao, Chai, Su, Chuang, Liu, Chen, Dou, Chen, Chen, Liao and Yu.)

Chemotherapy-induced neurotoxicity is a common adverse effect of cancer treatment. No medication has been shown to be effective in the prevention or treatment of chemotherapy-induced neurotoxicity. Using minoxidil as an initial template for structural modifications in conjunction with an in vitro neurite outgrowth assay, an image-based high-content screening platform, and mouse behavior models, an effective neuroprotective agent CN016 was discovered. Our results showed that CN016 could inhibit paclitaxel-induced inflammatory responses and infiltration of immune cells into sensory neurons significantly. Thus, the suppression of proinflammatory factors elucidates, in part, the mechanism of action of CN016 on alleviating paclitaxel-induced peripheral neuropathy. Based on excellent efficacy in improving behavioral functions, high safety profiles (MTD > 500 mg/kg), and a large therapeutic window (MTD/MED > 50) in mice, CN016 might have great potential to become a peripherally neuroprotective agent to prevent neurotoxicity caused by chemotherapeutics as typified by paclitaxel.

An efficient Ugi multicomponent reaction with strain promoted azide-alkyne cycloaddition protocol has been utilized in concert or independently to prepare a small family of bioactive zinc(II) dipicolylamine (ZnDPA)-based SN-38 conjugates. With sequential click chemistry coupling between the cytotoxic payload and phosphatidylserine-targeting ZnDPA ligand derived from structurally diverse carboxylic acids, aldehyde or ketones, and isocyanides, we demonstrated that this convergent synthetic strategy could furnish conjugates harnessing diversified linkers that exhibited different pharmacokinetic profiles in systemic circulation in vivo . Among the eight new conjugates, comparative studies on in vitro cytotoxicities, plasma stabilities, in vivo pharmacokinetic properties, and maximum tolerated doses were then carried out to identify a potent ZnDPA-based SN-38 conjugate that resulted in pancreatic cancer growth regression with an 80% reduction of cytotoxic payload used when compared to that of the marketed irinotecan. Our work provided the roadmap to construct a variety of theranostic agents in a similar manner for cancer treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tsai, Chiu, Chen, Hsu, Tsai, Yeh, Huang and Tsou.)

Background: Previous studies showed inconsistent Results of the effects of dipeptidyl peptidase (DPP)-IV inhibitors on syngeneic mouse islet transplantation. We hypothesized that the implanted islet numbers are critical for the effects of DPP-IV inhibitors on the outcomes of transplantation., Methods: One hundred and fifty or three hundred islets were syngeneically transplanted under the renal capsule of each streptozocin-diabetic C57BL/6 mouse and recipients were then treated without or with LAF237 (10 mg/kg/day, po) for 6 weeks. After transplantation, recipients' blood glucose, body weight and intraperitoneal glucose tolerance test (IPGTT) were followed-up periodically. The graft was removed for the measurement of β-cell mass at 6 weeks., Results: In recipients with 150 islets, it was not significantly different between the LAF237- treated group (n = 14) and control group (n = 14) in terms of the blood glucose, body weight, glucose tolerance at 2, 4 and 6 weeks or the graft β-cell mass at 6 weeks. In contrast, in recipients with 300 islets, the LAF237-treated group (n = 24) did have a lower area under the curve of the IPGTT at 4 weeks (p = 0.0237) and 6 weeks (p = 0.0113) as well as more graft β-cell mass at 6 weeks (0.655 ± 0.008 mg vs. 0.435 ± 0.006 mg, p = 0.0463) than controls (n = 24)., Conclusions: Our findings revealed 6-week treatment of LAF237 improves glucose tolerance and increases graft β-cell mass in diabetic mice transplanted with a sufficient number but not a marginal number of islets. These indicate that the effects of DPP-IV inhibitors are influenced by the implanted islet mass., Competing Interests: Conflicts of interest The authors declare no conflicts of interests., (Copyright © 2020 Chang Gung University. Published by Elsevier B.V. All rights reserved.)

Targeted oral delivery of a drug via the intestinal lymphatic system (ILS) has the advantages of protecting against hepatic first-pass metabolism of the drug and improving its pharmacokinetic performance. It is also a promising route for the oral delivery of vaccines and therapeutic agents to induce mucosal immune responses and treat lymphatic diseases, respectively. This article describes the anatomical structures and physiological characteristics of the ILS, with an emphasis on enterocytes and microfold (M) cells, which are the main gateways for the transport of particulate delivery vehicles across the intestinal epithelium into the lymphatics. A comprehensive overview of recent advances in the rational engineering of particulate vehicles, along with the challenges and opportunities that they present for improving ILS drug delivery, is provided, and the mechanisms by which such vehicles target and transport through enterocytes or M cells are discussed. The use of naturally sourced materials, such as yeast microcapsules and their derived polymeric β-glucans, as novel ILS-targeting delivery vehicles is also reviewed. Such use is the focus of an emerging field of research. Their potential use in the oral delivery of nucleic acids, such as mRNA vaccines, is proposed., (© 2021 Wiley-VCH GmbH.)

Rare oncogenic NTRK gene fusions result in uncontrolled TRK signaling leading to various adult and pediatric solid tumors. Based on the architecture of our multi-targeted clinical candidate BPR1K871 (10), we designed and synthesized a series of quinazoline compounds as selective and orally bioavailable type II TRK inhibitors. Property-driven and lead optimization strategies informed by structure-activity relationship studies led to the identification of 39, which showed higher (about 15-fold) selectivity for TRKA over AURA and AURB, as well as potent cellular activity (IC 50  = 56.4 nM) against the KM12 human colorectal cancer cell line. 39 also displayed good AUC and oral bioavailability (F = 27%), excellent in vivo efficacy (TGI = 64%) in a KM12 xenograft model, and broad-spectrum anti-TRK mutant potency (IC 50  = 3.74-151.4 nM), especially in the double-mutant TRKA enzymatic assays. 39 is therefore proposed for further development as a next-generation, selective, and orally-administered type II TRK inhibitor., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Colony-stimulating factor-1 receptor (CSF1R) is implicated in tumor-associated macrophage (TAM) repolarization and has emerged as a promising target for cancer immunotherapy. Herein, we describe the discovery of orally active and selective CSF1R inhibitors by property-driven optimization of BPR1K871 ( 9 ), our clinical multitargeting kinase inhibitor. Molecular docking revealed an additional nonclassical hydrogen-bonding (NCHB) interaction between the unique 7-aminoquinazoline scaffold and the CSF1R hinge region, contributing to CSF1R potency enhancement. Structural studies of CSF1R and Aurora kinase B (AURB) demonstrated the differences in their back pockets, which inspired the use of a chain extension strategy to diminish the AURA/B activities. A lead compound BPR1R024 ( 12 ) exhibited potent CSF1R activity (IC 50 = 0.53 nM) and specifically inhibited protumor M2-like macrophage survival with a minimal effect on antitumor M1-like macrophage growth. In vivo , oral administration of 12 mesylate delayed the MC38 murine colon tumor growth and reversed the immunosuppressive tumor microenvironment with the increased M1/M2 ratio.

Remdesivir, a prodrug targeting RNA-dependent-RNA-polymerase, and cyclosporine, a calcineurin inhibitor, individually exerted inhibitory activity against human coronavirus OC43 (HCoV-OC43) in HCT-8 and MRC-5 cells at EC 50 values of 96 ± 34 ∼ 85 ± 23 nM and 2,920 ± 364 ∼ 4,419 ± 490 nM, respectively. When combined, these two drugs synergistically inhibited HCoV-OC43 in both HCT-8 and MRC-5 cells assayed by immunofluorescence assay (IFA). Remdesivir and cyclosporine also separately reduced IL-6 production induced by HCoV-OC43 in human lung fibroblasts MRC-5 cells with EC 50 values of 224 ± 53 nM and 1,292 ± 352 nM, respectively; and synergistically reduced it when combined. Similar trends were observed for SARS-CoV-2, which were 1) separately inhibited by remdesivir and cyclosporine with respective EC 50 values of 3,962 ± 303 nM and 7,213 ± 143 nM by IFA, and 291 ± 91 nM and 6,767 ± 1,827 nM by a plaque-formation assay; and 2) synergistically inhibited by their combination, again by IFA and plaque-formation assay. Collectively, these results suggest that the combination of remdesivir and cyclosporine merits further study as a possible treatment for COVID-19 complexed with a cytokine storm., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hsu, Yang, Lee, Lin, Chang, Yang, Liang, Chao, Liao, Kao, Wu, Chang, Sytwu, Chen and Lee.)

Aims: Dipeptidyl peptidase 4 (DPP-4) is a valid molecular drug target from which its inhibitors have been developed as medicines for treating diabetes. The present study evaluated a new synthetic DPP-4-specific inhibitor of small molecule DBPR108 for pharmacology and pharmacokinetic profiles., Main Methods: DBPR108 of various doses was orally administered to rats, diabetic mice, and dogs and the systemic circulating DPP-4 activities in the animals were measured to demonstrate the pharmacological mechanisms of action via DPP-4 inhibition. Upon an oral administration of DBPR108, the serum active GLP-1 and insulin levels of the rats challenged with an oral glucose ingestion were measured. Oral glucose tolerance test in diet-induced obese mice was performed to examine if DBPR108 increases the glucose tolerability in animals., Key Findings: Orally administered DBPR108 inhibited the systemic plasma DPP-4 activities in rats, dogs and diabetic mice in a dose-dependent manner. DBPR108 caused elevated serum levels of active GLP-1 and insulin in the rats. DBPR108 dose-dependently increased the glucose tolerability in diet-induced obese (DIO) mice and, furthermore, DIO mice treated with DBPR108 (0.1 mg/kg) in combination with metformin (50 or 100 mg/kg) showed a prominently strong increase in the glucose tolerability., Significance: DBPR108 is a novel DPP-4-selective inhibitor of small molecule that demonstrated potent in vivo pharmacological effects and good safety profiles in animals. DBPR108 is now a drug candidate being further developed in the clinical studies as therapeutics for treating diabetes., (Copyright © 2021. Published by Elsevier Inc.)

Most orally administered drugs fail to reach the intracerebral regions because of the intestinal epithelial barrier (IEB) and the blood-brain barrier (BBB), which are located between the gut and the brain. Herein, an oral prodrug delivery system that can overcome both the IEB and the BBB noninvasively is developed for treating gliomas. The prodrug is prepared by conjugating an anticancer drug on β-glucans using a disulfide-containing linker. Following oral administration in glioma-bearing mice, the as-prepared prodrug can specifically target intestinal M cells, transpass the IEB, and be phagocytosed/hitchhiked by local macrophages (Mϕ). The Mϕ-hitchhiked prodrug is transported to the circulatory system via the lymphatic system, crossing the BBB. The tumor-overexpressed glutathione then cleaves the disulfide bond within the prodrug, releasing the active drug, improving its therapeutic efficacy. These findings reveal that the developed prodrug may serve as a gut-to-brain oral drug delivery platform for the well-targeted treatment of gliomas., (© 2021 Wiley-VCH GmbH.)

The A-type Aurora kinase is upregulated in many human cancers, and it stabilizes MYC-family oncoproteins, which have long been considered an undruggable target. Here, we describe the design and synthesis of a series of pyrimidine-based derivatives able to inhibit Aurora A kinase activity and reduce levels of cMYC and MYCN. Through structure-based drug design of a small molecule that induces the DFG-out conformation of Aurora A kinase, lead compound 13 was identified, which potently (IC 50 < 200 nM) inhibited the proliferation of high-MYC expressing small-cell lung cancer (SCLC) cell lines. Pharmacokinetic optimization of 13 by prodrug strategies resulted in orally bioavailable 25 , which demonstrated an 8-fold higher oral AUC ( F = 62.3%). Pharmacodynamic studies of 25 showed it to effectively reduce cMYC protein levels, leading to >80% tumor regression of NCI-H446 SCLC xenograft tumors in mice. These results support the potential of 25 for the treatment of MYC -amplified cancers including SCLC.

Reactivation of fetal hemoglobin (HbF) expression by therapeutic agents has been suggested as an alternative treatment to modulate anemia and the related symptoms of severe β-thalassemia and sickle cell disease (SCD). Hydroxyurea (HU) is the first US FDA-approved HbF inducer for treating SCD. However, approximately 25% of the patients with SCD do not respond to HU. A previous study identified TN1 (1) as a small-molecule HbF inducer. However, this study found that the poor potency and oral bioavailability of compound 1 limits the development of this inducer for clinical use. To develop drug-like compounds, further structure-activity relationship studies on the purine-based structure of 1 were conducted. Herein, we report our discovery of a more potent inducer, compound 13a, that can efficiently induce γ-globin gene expression at non-cytotoxic concentrations. The molecular mechanism of 13a, for the regulation HbF expression, was also investigated. In addition, we demonstrated that oral administration of 13a can ameliorate anemia and the related symptoms in SCD mice. The results of this study suggest that 13a can be further developed as a novel agent for treating hemoglobinopathies, such as β-thalassemia and SCD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Zinc(II)-dipicolylamine (Zn-DPA) has been shown to specifically identify and bind to phosphatidylserine (PS), which exists in bulk in the tumor microenvironment. BPRDP056, a Zn-DPA-SN38 conjugate was designed to provide PS-targeted drug delivery of a cytotoxic SN38 to the tumor microenvironment, thereby allowing a lower dosage of SN38 that induces apoptosis in cancer cells. Micro-Western assay showed that BPRDP056 exhibited apoptotic signal levels similar to those of CPT-11 in the treated tumors growing in mice. Pharmacokinetic study showed that BPRDP056 has excellent systemic stability in circulation in mice and rats. BPRDP056 is accumulated in tumors and thus increases the cytotoxic effects of SN38. The in vivo antitumor activities of BPRDP056 have been shown to be significant in subcutaneous pancreas, prostate, colon, liver, breast, and glioblastoma tumors, included an orthotopic pancreatic tumor, in mice. BPRDP056 shrunk tumors at a lower (~20% only) dosing intensity of SN38 compared to that of SN38 conjugated in CPT-11 in all tumor models tested. A wide spectrum of antitumor activities is expected to treat all cancer types of PS-rich tumor microenvironments. BPRDP056 is a first-in-class small molecule drug conjugate for cancer therapy., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: A patent (international application number: PCT/US2015/031386) has been filed in relation to this work. The authors, Y.S.C., L.K.T., and C.T.C, are also co-inventors in the patent. The authors declare no additional competing financial interests., (Copyright © 2020. Published by Elsevier Inc.)

Tylophorine-based compounds and natural cardiotonic steroids (cardenolides and bufadienolides) are two classes of transmissible gastroenteritis coronavirus inhibitors, targeting viral RNA and host cell factors, respectively. We tested both types of compounds against two types of coronaviruses, to compare and contrast their antiviral properties, and with view to their further therapeutic development. Examples of both types of compounds potently inhibited the replication of both feline infectious peritonitis virus and human coronavirus OC43 with EC 50 values of up to 8 and 16 nM, respectively. Strikingly, the tylophorine-based compounds tested inhibited viral yields of HCoV-OC43 to a much greater extent (7-8 log magnitudes of p.f.u./ml) than the cardiotonic steroids (about 2-3 log magnitudes of p.f.u./ml), as determined by end point assays. Based on these results, three tylophorine-based compounds were further examined for their anti-viral activities on two other human coronaviruses, HCoV-229E and SARS-CoV-2. These three tylophorine-based compounds inhibited HCoV-229E with EC 50 values of up to 6.5 nM, inhibited viral yields of HCoV-229E by 6-7 log magnitudes of p.f.u./ml, and were also found to inhibit SARS-CoV-2 with EC 50 values of up to 2.5-14 nM. In conclusion, tylophorine-based compounds are potent, broad-spectrum inhibitors of coronaviruses including SARS-CoV-2, and could be used for the treatment of COVID-19., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Yang, Lee, Hsu, Jan, Lin, Chang, Peng, Yang, Liang, Liao, Chao, Pang, Kao, Huang, Lin, Chang, Niu, Wu, Sytwu, Chen and Lee.)

Non-small-cell lung cancer (NSCLC) is a leading cause of cancer-related death worldwide. NSCLC patients with overexpressed or mutated epidermal growth factor receptor (EGFR) related to disease progression are treated with EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Acquired drug resistance after TKI treatments has been a major focus for development of NSCLC therapies. This study aimed to establish afatinib-resistant cell lines from which afatinib resistance-associated genes are identified and the underlying mechanisms of multiple-TKI resistance in NSCLC can be further investigated. Nude mice bearing subcutaneous NSCLC HCC827 tumors were administered with afatinib at different dose intensities (5-100 mg/kg). We established three HCC827 sublines resistant to afatinib (IC 50 > 1 μM) with cross-resistance to gefitinib (IC 50 > 5 μM). cDNA microarray revealed several of these sublines shared 27 up- and 13 down-regulated genes. The mRNA expression of selective novel genes - such as transmembrane 4 L six family member 19 (TM4SF19), suppressor of cytokine signaling 2 (SOCS2), and quinolinate phosphoribosyltransferase (QPRT) - are responsive to afatinib treatments only at high concentrations. Furthermore, c-MET amplification and activations of a subset of tyrosine kinase receptors were observed in all three resistant cells. PHA665752, a c-MET inhibitor, remarkably increased the sensitivity of these resistant cells to afatinib (IC 50 = 12-123 nM). We established afatinib-resistant lung cancer cell lines and here report genes associated with afatinib resistance in human NSCLC. These cell lines and the identified genes serve as useful investigational tools, prognostic biomarkers of TKI therapies, and promising molecule targets for development of human NSCLC therapeutics., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Machine learning is a well-known approach for virtual screening. Recently, deep learning, a machine learning algorithm in artificial neural networks, has been applied to the advancement of precision medicine and drug discovery. In this study, we performed comparative studies between deep neural networks (DNN) and other ligand-based virtual screening (LBVS) methods to demonstrate that DNN and random forest (RF) were superior in hit prediction efficiency. By using DNN, several triple-negative breast cancer (TNBC) inhibitors were identified as potent hits from a screening of an in-house database of 165,000 compounds. In broadening the application of this method, we harnessed the predictive properties of trained model in the discovery of G protein-coupled receptor (GPCR) agonist, by which computational structure-based design of molecules could be greatly hindered by lack of structural information. Notably, a potent (~ 500 nM) mu-opioid receptor (MOR) agonist was identified as a hit from a small-size training set of 63 compounds. Our results show that DNN could be an efficient module in hit prediction and provide experimental evidence that machine learning could identify potent hits in silico from a limited training set.

The therapeutic outcome of pancreatic cancer remains unsatisfactory, despite many attempts to improve it. To address this challenge, an oral drug delivery system that spontaneously initiates an effervescent reaction to form gas-bubble carriers is proposed. These carriers concurrently deliver lipophilic paclitaxel (PTX) and hydrophilic gemcitabine (GEM) in the small intestine. The bursting of the bubbles promotes the intestinal absorption of the drugs. The antitumor efficacy of this proposed oral drug delivery system is evaluated in rats with experimentally created orthotopic pancreatic tumors. The combined administration of equivalent amounts of PTX and GEM via the intravenous (i.v.) route, which is clinically used for treating pancreatic cancer, serves as a control. Following oral administration, the lipophilic PTX is initially absorbed through the intestinal lymphatic system and then enters systemic circulation, whereas the hydrophilic GEM is directly taken up into the blood circulation, ultimately accumulating in the tumorous pancreatic tissues. A pharmacokinetic study reveals that the orally delivered formulation has none of the toxic side-effects that are associated with the i.v. injected formulation; changes the pharmacokinetic profiles of the drugs; and increases the bioavailability of PTX. The oral formulation has a greater impact than the i.v. formulation on tumor-specific stromal depletion, resulting in greater inhibition of tumor growth with no evidence of metastatic spread. As well as enhancing the therapeutic efficacy, this unique approach of oral chemotherapy has potential for use on outpatients, greatly improving their quality of life., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The coronavirus (CoV) disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome CoV-2 (SARS-CoV-2) is a health threat worldwide. Viral main protease (M pro , also called 3C-like protease [3CL pro ]) is a therapeutic target for drug discovery. Herein, we report that GC376, a broad-spectrum inhibitor targeting M pro in the picornavirus-like supercluster, is a potent inhibitor for the M pro encoded by SARS-CoV-2, with a half-maximum inhibitory concentration (IC 50 ) of 26.4 ± 1.1 nM. In this study, we also show that GC376 inhibits SARS-CoV-2 replication with a half-maximum effective concentration (EC 50 ) of 0.91 ± 0.03 μM. Only a small portion of SARS-CoV-2 M pro was covalently modified in the excess of GC376 as evaluated by mass spectrometry analysis, indicating that improved inhibitors are needed. Subsequently, molecular docking analysis revealed that the recognition and binding groups of GC376 within the active site of SARS-CoV-2 M pro provide important new information for the optimization of GC376. Given that sufficient safety and efficacy data are available for GC376 as an investigational veterinary drug, expedited development of GC376, or its optimized analogues, for treatment of SARS-CoV-2 infection in human is recommended., (Copyright © 2020 Hung et al.)

Background: New therapeutic options to address the ongoing coronavirus disease 2019 (COVID-19) pandemic are urgently needed. One possible strategy is the repurposing of existing drugs approved for other indications as antiviral agents for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Due to the commercial unavailability of SARS-CoV-2 drugs for treating COVID-19, we screened approximately 250 existing drugs or pharmacologically active compounds for their inhibitory activities against feline infectious peritonitis coronavirus (FIPV) and human coronavirus OC43 (HCoV-OC43), a human coronavirus in the same genus (Betacoronavirus) as SARS-CoV-2., Methods: FIPV was proliferated in feline Fcwf-4 cells and HCoV-OC43 in human HCT-8 cells. Viral proliferation was assayed by visualization of cytopathic effects on the infected Fcwf-4 cells and immunofluorescent assay for detection of the nucleocapsid proteins of HCoV-OC43 in the HCT-8 cells. The concentrations (EC 50 ) of each drug necessary to diminish viral activity to 50% of that for the untreated controls were determined. The viabilities of Fcwf-4 and HCT-8 cells were measured by crystal violet staining and MTS/PMS assay, respectively., Results: Fifteen out of the 252 drugs or pharmacologically active compounds screened were found to be active against both FIPV and HCoV-OC43, with EC 50 values ranging from 11 nM to 75 μM. They are all old drugs as follows, anisomycin, antimycin A, atovaquone, chloroquine, conivaptan, emetine, gemcitabine, homoharringtonine, niclosamide, nitazoxanide, oligomycin, salinomycin, tilorone, valinomycin, and vismodegib., Conclusion: All of the old drugs identified as having activity against FIPV and HCoV-OC43 have seen clinical use in their respective indications and are associated with known dosing schedules and adverse effect or toxicity profiles in humans. Those, when later confirmed to have an anti-viral effect on SARS-CoV-2, should be considered for immediate uses in COVID-19 patients., Competing Interests: Conflicts of Interest The authors declare no conflict of interest., (Copyright © 2020 Chang Gung University. Published by Elsevier B.V. All rights reserved.)

Background: The ongoing COVID-19 pandemic has caused more than 193,825 deaths during the past few months. A quick-to-be-identified cure for the disease will be a therapeutic medicine that has prior use experiences in patients in order to resolve the current pandemic situation before it could become worsening. Artificial intelligence (AI) technology is hereby applied to identify the marketed drugs with potential for treating COVID-19., Methods: An AI platform was established to identify potential old drugs with anti-coronavirus activities by using two different learning databases; one consisted of the compounds reported or proven active against SARS-CoV, SARS-CoV-2, human immunodeficiency virus, influenza virus, and the other one containing the known 3C-like protease inhibitors. All AI predicted drugs were then tested for activities against a feline coronavirus in in vitro cell-based assay. These assay results were feedbacks to the AI system for relearning and thus to generate a modified AI model to search for old drugs again., Results: After a few runs of AI learning and prediction processes, the AI system identified 80 marketed drugs with potential. Among them, 8 drugs (bedaquiline, brequinar, celecoxib, clofazimine, conivaptan, gemcitabine, tolcapone, and vismodegib) showed in vitro activities against the proliferation of a feline infectious peritonitis (FIP) virus in Fcwf-4 cells. In addition, 5 other drugs (boceprevir, chloroquine, homoharringtonine, tilorone, and salinomycin) were also found active during the exercises of AI approaches., Conclusion: Having taken advantages of AI, we identified old drugs with activities against FIP coronavirus. Further studies are underway to demonstrate their activities against SARS-CoV-2 in vitro and in vivo at clinically achievable concentrations and doses. With prior use experiences in patients, these old drugs if proven active against SARS-CoV-2 can readily be applied for fighting COVID-19 pandemic., Competing Interests: The authors declare that they have no competing interests., (© 2020 Chang Gung University. Publishing services by Elsevier B.V.)

A major obstacle to nanodrugs-mediated cancer therapy is their rapid uptake by the reticuloendothelial system that decreases the systemic exposure of the nanodrugs to tumors and also increases toxicities. Intralipid has been shown to reduce nano-oxaliplatin-mediated toxicity while improving bioavailability. Here, we have found that Intralipid reduces the cytotoxicity of paclitaxel for human monocytic cells, but not for breast, lung, or pancreatic cancer cells. Intralipid also promotes the polarization of macrophages to the anti-cancer M1-like phenotype. Using a xenograft breast cancer mouse model, we have found that Intralipid pre-treatment significantly increases the amount of paclitaxel reaching the tumor and promotes tumor apoptosis. The combination of Intralipid with half the standard clinical dose of Abraxane reduces the tumor growth rate as effectively as the standard clinical dose. Our findings suggest that pre-treatment of Intralipid has the potential to be a powerful agent to enhance the tumor cytotoxic effects of Abraxane and to reduce its off-target toxicities.

Gastrointestinal stromal tumors (GISTs) are prototypes of stem cell factor receptor (c-KIT)-driven cancer. Two receptor tyrosine kinases, c-KIT and fms-tyrosine kinase (FLT3), are frequently mutated in acute myeloid leukemia (AML) patients, and these mutations are associated with poor prognosis. In this study, we discovered a multitargeted tyrosine kinase inhibitor, compound 15a , with potent inhibition against single or double mutations of c-KIT developed in GISTs. Moreover, crystal structure analysis revealed the unique binding mode of 15a with c-KIT and may elucidate its high potency in inhibiting c-KIT kinase activity. Compound 15a inhibited cell proliferation and induced apoptosis by targeting c-KIT in c-KIT-mutant GIST cell lines. The antitumor effects of 15a were also demonstrated in GIST430 and GIST patient-derived xenograft models. Further studies demonstrated that 15a inhibited the proliferation of c-KIT- and FLT3-driven AML cells in vitro and in vivo. The results of this study suggest that 15a may be a potential anticancer drug for the treatment of GISTs and AML.

Dengue virus (DENV) is a global health problem that affects approximately 3.9 billion people worldwide. Since safety concerns were raised for the only licensed vaccine, Dengvaxia, and since the present treatment is only supportive care, the development of more effective therapeutic anti-DENV agents is urgently needed. In this report, we identified a potential small-molecule inhibitor, BP34610, via cell-based high-throughput screening (HTS) of 12,000 compounds using DENV-2 reporter viruses. BP34610 reduced the virus yields of type 2 DENV-infected cells with a 50% effective concentration (EC 50 ) and selectivity index value of 0.48 ± 0.06 μM and 197, respectively. Without detectable cytotoxicity, the compound inhibited not only all four serotypes of DENV but also Japanese encephalitis virus (JEV). Time-of-addition experiments suggested that BP34610 may act at an early stage of DENV virus infection. Sequencing analyses of several individual clones derived from BP34610-resistant viruses revealed a consensus amino acid substitution (S397P) in the N-terminal stem region of the E protein. Introduction of S397P into the DENV reporter viruses conferred an over 14.8-fold EC 90 shift for BP34610. Importantly, the combination of BP34610 with a viral replication inhibitor, ribavirin, displayed synergistic enhancement of anti-DENV-2 activity. Our results identify an effective small-molecule inhibitor, BP34610, which likely targets the DENV E protein. BP34610 could be developed as an anti-flavivirus agent in the future., (Copyright © 2019. Published by Elsevier B.V.)

Epidermal growth factor receptor (EGFR)-targeted therapy in non-small cell lung cancer represents a breakthrough in the field of precision medicine. Previously, we have identified a lead compound, furanopyrimidine 2 , which contains a ( S )-2-phenylglycinol structure as a key fragment to inhibit EGFR. However, compound 2 showed high clearance and poor oral bioavailability in its pharmacokinetics studies. In this work, we optimized compound 2 by scaffold hopping and exploiting the potent inhibitory activity of various warhead groups to obtain a clinical candidate, 78 (DBPR112), which not only displayed a potent inhibitory activity against EGFR L858R/T790M double mutations but also exhibited tenfold potency better than the third-generation inhibitor, osimertinib, against EGFR and HER2 exon 20 insertion mutations. Overall, pharmacokinetic improvement through lead-to-candidate optimization yielded fourfold oral AUC better that afatinib along with F = 41.5%, an encouraging safety profile, and significant antitumor efficacy in in vivo xenograft models. DBPR112 is currently undergoing phase 1 clinical trial in Taiwan.

Background: Boschniakia rossica is a well-known traditional Chinese medicine for tonifying kidney and improving impotence. Boschnaloside is the major iridoid glycoside in this herb but therapeutic benefits for diabetes remained to be evaluated., Hypothesis/purpose: The current investigation aims to study the antidiabetic effect and the underlying pharmacological mechanisms., Study Design and Methods: Receptor binding, cAMP production, Ins secretion, glucagon-like peptide 1 (GLP-1) secretion, and dipeptidyl peptidase-4 activity assays were performed. Therapeutic benefits of orally administrated boschnaloside (150 and 300 mg/kg/day) were evaluated using severely 12-week old female diabetic db/db mice (Hemoglobin A1c >10%)., Results: Oral treatment of boschnaloside for 4 weeks improved diabetic symptoms including fasting blood sugar, hemoglobin A1c, glucose intolerance, and Homeostatic Model Assessment of Ins Resistance, accompanied by circulating GLP-1 active and adiponectin levels. In addition, bochnaloside treatment improved islet/β cell function associated with an alteration of the pancreatic and duodenal homeobox 1 level. It was shown that boschnaloside interacted with the extracellular domain of GLP-1 receptor and enhanced glucose stimulated Ins secretion. Boschnaloside also augmented the insulinotropic effect of GLP-1. Finally, the presence of boschnaloside caused a reduction of dipeptidyl peptidase-4 activity while enhanced GLP-1 secretion from STC-1 cells., Conclusion: It appears that bochnaloside at oral dosage greater than 150 mg/kg/day exerts antidiabetic effects in vivo through modulating the action of GLP-1., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

Host cells infected with dengue virus (DENV) often trigger endoplasmic reticulum (ER) stress, a key process that allows viral reproduction, without killing the host cells until the late stage of the virus life-cycle. However, little is known regarding which DENV viral proteins interact with the ER machinery to support viral replication. In this study, we identified and characterized a novel host factor, stress-associated ER protein 1 (SERP1), which interacts with the DENV type 2 (DENV-2) NS4B protein by several assays, for example, yeast two-hybrid, subcellular localization, NanoBiT complementation, and co-immunoprecipitation. A drastic increase (34.5-fold) in the SERP1 gene expression was observed in the DENV-2-infected or replicon-transfected Huh7.5 cells. The SERP1 overexpression inhibited viral yields (37-fold) in the DENV-2-infected Huh7.5 cells. In contrast, shRNAi-knockdown and the knockout of SERP1 increased the viral yields (3.4- and 16-fold, respectively) in DENV-2-infected HEK-293 and Huh7.5 cells, respectively. DENV-2 viral RNA replication was severely reduced in stable SERP1-expressing Huh7.5 cells transfected with DENV-2 replicon plasmids. The overexpression of DENV-2 NS4B alleviated the inhibitory effect of SERP1 on DENV-2 RNA replication. Taking these results together, we hypothesized that SERP1 may serve as an antiviral player during ER stress to restrict DENV-2 infection. Our studies revealed novel anti-DENV drug targets that may facilitate anti-DENV drug discovery.

We report that compound 13 , a novel phosphatidylserine-targeting zinc(II) dipicolylamine drug conjugate, readily triggers a positive feedback therapeutic loop through the in situ generation of phosphatidylserine in the tumor microenvironment. Linker modifications, pharmacokinetics profiling, in vivo antitumor studies, and micro-Western array of treated-tumor tissues were employed to show that this class of conjugates induced regeneration of apoptotic signals, which facilitated subsequent recruitment of the circulating conjugates through the zinc(II) dipicolylamine-phosphatidylserine association and resulted in compounding antitumor efficacy. Compared to the marketed compound 17 , compound 13 not only induced regressions in colorectal and pancreatic tumor models, it also exhibited at least 5-fold enhancement in antitumor efficacy with only 40% of the drug employed during treatment, culminating in a >12.5-fold increase in therapeutic potential. Our study discloses a chemically distinct apoptosis-targeting theranostic, with built-in complementary functional moieties between the targeting module and the drug mechanism to expand the arsenal of antitumor therapy.

Background/aim: Our current study aimed to determine the molecular mechanisms of citronellol-induced cell death and ROS accumulation in non-small cell lung cancer (NCI-H1299 cells) and also compare the anticancer effects of citronellol and EOPC., Materials and Methods: ROS measurement and western blotting were performed to detect whether citronellol can induce necroptosis in vitro. Besides, we performed an in vivo analysis of tumourigenesis inhibition by citronellol treatment in BALB/c (nu/nu) nude mice., Results: Necroptosis occured by up-regulating TNF-α, RIP1/RIP3 activities, and down-regulating caspase-3/caspase-8 activities after citronellol treatment in NCI-H1299 cells. Citronellol also resulted in a biphasic increase in ROS production at 1 h and at 12 h in NCI-H1299 cells. Xenograft model experiments showed that citronellol could effectively inhibit subcutaneous tumours produced 4 weeks after intraperitoneal injection of NCI-H1299 in BALB/c nude mice., Conclusion: Citronellol induced necroptosis of NCI-H1299 cells via TNF-α pathway and ROS accumulation., (Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Head and neck squamous cell carcinoma (HNSCC) is one of the leading causes of cancer deaths worldwide, especially in male. With poor prognosis, significant portions of patients with HNSCC die due to cancer recurrence and tumor metastasis after chemotherapy and targeted therapies. The HNSCC FaDu cell ectopic expression of Twist, a key transcriptional factor of epithelial-mesenchymal transition (EMT), which triggers EMT and results in the acquisition of a mesenchymal phenotype, was used as the cell model. Our results demonstrated that treatment with newly synthesized 2-(3-hydroxyphenyl)-5-methylnaphthyridin-4-one (CSC-3436), a flavonoid derivative, elicited changes in its cell morphology, upregulated E-cadherin messenger RNA and protein expression, downregulated N-cadherin, vimentin, and CD133 (a marker associated with tumor-initiating cells) in FaDu-pCDH-Twist cells. Moreover, CSC-3436 exposure reduced B cell-specific Moloney murine leukemia virus integration site 1 (Bmi1) expression regulated by Twist and further suppressed the direct co-regulation of E-cadherin by Twist and Bmi1. Interestingly, CSC-3436 reduced EMT, cancer stemness, and migration/invasion abilities through the inhibition of the Twist/Bmi1-Akt/β-catenin pathway. Most importantly, our findings provided new evidence that CSC-3436 played a crucial role in therapeutic targeting to Bmi1 and its molecular pathway in HNSCC, and it will be valuable in prognostic prediction and treatment., (© 2018 Wiley Periodicals, Inc.)

Drug resistance due to acquired mutations that constitutively activate c-KIT is a significant challenge in the treatment of patients with gastrointestinal stromal tumors (GISTs). Herein, we identified 1-(5-ethyl-isoxazol-3-yl)-3-(4-{2-[6-(4-ethylpiperazin-1-yl)pyrimidin-4-ylamino]-thiazol-5-yl}phenyl)urea (10a) as a potent inhibitor against unactivated and activated c-KIT. The binding of 10a induced rearrangements of the DFG motif, αC-helix, juxtamembrane domain, and the activation loop to switch the activated c-KIT back to its structurally inactive state. To the best of our knowledge, it is the first structural evidence demonstrating how a compound can inhibit the activated c-KIT by switching back to its inactive state through a sequence of conformational changes. Moreover, 10a can effectively inhibit various c-KIT mutants and the proliferation of several GIST cell lines. The distinct binding features and superior inhibitory potency of 10a, together with its excellent efficacy in the xenograft model, establish 10a as worthy of further clinical evaluation in the advanced GISTs.

A medicinal chemistry program based on the small-molecule HCV NS5A inhibitor daclatasvir has led to the discovery of dimeric phenylthiazole compound 8, a novel and potent HCV NS5A inhibitor. The subsequent SAR studies and optimization revealed that the cycloalkyl amide derivatives 27a-29a exhibited superior potency against GT1b with GT1b EC 50 values at picomolar concentration. Interestingly, high diastereospecificity for HCV inhibition was observed in this class with the (1R,2S,1'R,2'S) diastereomer displaying the highest GT1b inhibitory activity. The best inhibitor 27a was found to be 3-fold more potent (GT1b EC 50  = 0.003 nM) than daclatasvir (GT1b EC 50  = 0.009 nM) against GT1b, and no detectable in vitro cytotoxicity was observed (CC 50  > 50 μM). Pharmacokinetic studies demonstrated that compound 27a had an excellent pharmacokinetic profiles with a superior oral exposure and desired bioavailability after oral administration in both rats and dogs, and therefore it was selected as a developmental candidate for the treatment of HCV infection., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Morphine is widely used for the treatment of severe pain. This analgesic effect is mediated principally by the activation of μ-opioid receptors (MOR). However, prolonged activation of MOR also results in tolerance, dependence, addiction, constipation, nausea, sedation, and respiratory depression. To address this problem, we sought alternative ways to activate MOR - either by use of novel ligands, or via a novel activation mechanism. To this end, a series of compounds were screened using a sensitive CHO-K1/MOR/Gα15 cell-based FLIPR ® calcium high-throughput screening (HTS) assay, and the bithiazole compound 5a was identified as being able activate MOR in combination with naloxone. Structural modifications of 5a resulted in the discovery of lead compound 5j, which could effectively activate MOR in combination with the MOR antagonist naloxone or naltrexone. In vivo, naloxone in combination with 100 mg/kg of compound 5j elicited antinociception in a mouse tail-flick model with an ED 50 of 17.5 ± 4 mg/kg. These results strongly suggest that the mechanism by which the 5j/naloxone combination activates MOR is worthy of further study, as its discovery has the potential to yield an entirely novel class of analgesics., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

The NS4A protein of dengue virus (DENV) has a cytosolic N terminus and four transmembrane domains. NS4A participates in RNA replication and the host antiviral response. However, the roles of amino acid residues within the N-terminus of NS4A during the life cycle of DENV are not clear. Here we explore the function of DENV NS4A by introducing a series of alanine substitutions into the N-terminus of NS4A in the context of a DENV infectious clone or subgenomic replicon. Nine of 17 NS4A mutants displayed a lethal phenotype due to the impairment of RNA replication. M2 and M14 displayed a more than 10 000-fold reduction in viral yields and moderate defects in viral replication by a replicon assay. Sequencing analyses of pseudorevertant viruses derived from M2 and M14 viruses revealed one consensus reversion mutation, A21V, within NS4A. The A21V mutation apparently rescued viral RNA replication in the M2 and M14 mutants although not to wild-type (WT) levels but resulted in 100- and 1000-fold lower titres than that of the WT, respectively. M2 Rev1 (M2+A21V) and M14 Rev1 (M14+A21V) mutants displayed phenotypes of smaller plaque size and WT-like assembly/secretion by a transpackaging assay. A defect in the virus-induced cytopathic effect (CPE) was observed in HEK-293 cells infected with either M2 Rev1 or M14 Rev1 mutant virus by MitoCapture staining, cell proliferation and lactate dehydrogenase release assays. In conclusion, the results revealed the essential roles of the N-terminal NS4A in both RNA replication and virus-induced CPE. Intramolecular interactions in the N-terminus of NS4A were implicated.

Sodium-dependent glucose co-transporter 2 (SGLT2) inhibition has been demonstrated to efficiently control hyperglycemia via an insulin secretion-independent pathway. The unique mode of action eliminates the risk of hypoglycemia and makes SGLT2 inhibitors an attractive option for the treatment of type 2 diabetes. In a continuation of our previous studies on SGLT2 inhibitors bearing different sugar moieties, sixteen new N-glucosyl indole derivatives were designed, synthesized, and evaluated for their inhibitory activity against hSGLT2. Of these sixteen, acethydrazide-containing N-glucosyl indole 9d was found to be the most potent SGLT2 inhibitor, and caused a significant elevation in urine glucose excretion in rats at 50 mg/kg, relative to the vehicle control., (Copyright © 2018 Elsevier Inc. All rights reserved.)