Design, Synthesis and Antitumor Activity of Novel Selenium-Containing Tepotinib Derivatives as Dual Inhibitors of c-Met and TrxR.

Cellular mesenchymal-epithelial transition factor (c-Met), an oncogenic transmembrane receptor tyrosine kinase (RTK), plays an essential role in cell proliferation during embryo development and liver regeneration. Thioredoxin reductase (TrxR) is overexpressed and constitutively active in most tumors closely related to cancer recurrence. Multi-target-directed ligands (MTDLs) strategy provides a logical approach to drug combinations and would adequately address the pathological complexity of cancer. In this work, we designed and synthesized a series of selenium-containing tepotinib derivatives by means of selenium-based bioisosteric modifications and evaluated their antiproliferative activity. Most of these selenium-containing hybrids exhibited potent dual inhibitory activity toward c-Met and TrxR. Among them, compound 8b was the most active, with an IC50 value of 10 nM against MHCC97H cells. Studies on the mechanism of action revealed that compound 8b triggered cell cycle arrest at the G1 phase and caused ROS accumulations by targeting TrxR, and these effects eventually led to cell apoptosis. These findings strongly suggest that compound 8b serves as a dual inhibitor of c-Met and TrxR, warranting further exploitation for cancer therapy.

The synthesis and evaluation of new butadiene derivatives as tubulin polymerization inhibitors.

A series of new butadiene derivatives was synthesized and evaluated as tubulin polymerization inhibitors for the treatment of cancer. The optimal butadiene derivative, 9a, exhibited IC50 values of 0.056-0.089µM for five human cancer cell lines. This paper included a mechanistic study of the antiproliferative activity, including a tubulin polymerization assay, an examination of morphological alterations of cancer cells, an analysis of cell cycle arrest and an apoptosis assay.

Synthesis and biological evaluation of a new series of ebselen derivatives as glutathione peroxidase (GPx) mimics and cholinesterase inhibitors against Alzheimer's disease.

A series of ebselen derivatives were designed, synthesised and evaluated as inhibitors of cholinesterases (ChEs) and glutathione peroxidase (GPx) mimics. Most of the compounds were found to be potent against AChEs and BuChE, compounds 5e and 5i, proved to be the most potent against AChE with IC50 values of 0.76 and 0.46 µM, respectively. Among these hybrids, most of the compounds were found to be good GPx mimics compare with ebselen. The selected compounds 5e and 5i were also used to determine the catalytic parameters and in vitro hydrogen peroxide scavenging activity. The results indicate that compounds 5e and 5i may be excellent multifunctional agents for the treatment of AD.

The lack of PPARα exacerbated the progression of non-alcoholic steatohepatitis in mice with spleen deficiency syndrome by triggering an inflammatory response.

Background: In addition to abnormal liver inflammation, the main symptoms of non-alcoholic steatohepatitis (NASH) are often accompanied by gastrointestinal digestive dysfunction, consistent with the concept of spleen deficiency (SD) in traditional Chinese medicine. As an important metabolic sensor, whether peroxisome proliferator-activated receptor alpha (PPARα) participates in regulating the occurrence and development of NASH with SD (NASH-SD) remains to be explored. Methods: Clinical liver samples were collected for RNA-seq analysis. C57BL/6J mice induced by folium sennae (SE) were used as an SD model. qPCR analysis was conducted to evaluate the inflammation and metabolic levels of mice. PPARα knockout mice (PPARαko) were subjected to SE and methionine-choline-deficient (MCD) diet to establish the NASH-SD model. The phenotype of NASH and the inflammatory indicators were measured using histopathologic analysis and qPCR as well. Results: The abnormal expression of PPARα signaling, coupled with metabolism and inflammation, was found in the results of RNA-seq analysis from clinical samples. SD mice showed a more severe inflammatory response in the liver evidenced by the increases in macrophage biomarkers, inflammatory factors, and fibrotic indicators in the liver. qPCR results also showed differences in PPARα between SD mice and control mice. In PPARαko mice, further evidence was found that the lack of PPARα exacerbated the inflammatory response phenotype as well as the lipid metabolism disorder in NASH-SD mice. Conclusion: The abnormal NR signaling accelerated the vicious cycle between lipotoxicity and inflammatory response in NAFLD with SD. Our results provide new evidence for nuclear receptors as potential therapeutic targets for NAFLD with spleen deficiency.

Identification of acetylshikonin as a novel tubulin polymerization inhibitor with antitumor activity in human hepatocellular carcinoma cells.

Background: Microtubules are attractive targets for anticancer drugs. However, the microtubule-targeting agents (MTAs) currently in clinical use exhibit inevitable drug resistance. Therefore, there is an urgent need to discover novel MTAs for the clinical treatment of cancer. Methods: Bioactive compounds extracted from Lithospermum erythrorhizon were assessed for in vitro anti-proliferative activities against a panel of human cancer cell lines using cell counting kit-8 (CCK-8) assay. Tubulin polymerization inhibition assay, colchicine competitive binding site assay, and immunofluorescence were used to validate the tubulin inhibition effect of acetylshikonin. Flow cytometry, Hoechst staining, and caspase-3 activity evaluation were performed to assess cell cycle arrest and cell apoptosis. 5,5',6,6'-tetrachloro-1,1',3,3'-tetramethylbenzimidazolylcarbocyanine iodide (JC-1) staining and dichloro-dihydro-fluorescein diacetate (DCFH-DA) staining were used to evaluate mitochondrial membrane potential (MMP) and reactive oxygen species (ROS), respectively. Results: Acetylshikonin exhibited potent anti-proliferative activities against a panel of human cancer cell lines (IC50 values: 1.09-7.26 µM) and displayed comparable cytotoxicity against several drug-resistant cell lines. Further mechanism studies revealed that acetylshikonin induced cell cycle arrest of MHCC-97H cells at G2/M phase, and significantly promoted apoptosis marked by a collapse of MMP and abnormal ROS accumulation. Conclusions: In this study, acetylshikonin was identified as MTA against hepatocellular carcinoma and can serve as a promising lead compound for further development of anti-cancer drug, underscoring its potential clinical significance.

Discovery of a Novel Stilbene Derivative as a Microtubule Targeting Agent Capable of Inducing Cell Ferroptosis.

Microtubule targeting agents (MTAs) are used as clinically effective chemotherapies for cancer treatment but might be limited by the acquired or intrinsic resistance of cancer cells to apoptosis. The vulnerability of therapy-resistant cancers to ferroptosis provides an alternative way to overcome drug resistance. In this study, on the basis of the MTAs obtained in our previous studies, a series of MTAs were synthesized, and detailed structure-activity relationships were obtained through extensive molecular dynamics studies. Among them, a diphenylethene derivative, compound 33, displayed the most potent activity in vitro and in vivo, with IC50 values of 10-50 nM toward six cancer cell lines and a 78.6% tumor growth inhibition in vivo. Interestingly, although it acted as the MTA, compound 33 triggered cell death mainly through cell ferroptosis rather than apoptosis, which might provide an alternative way to eradicate apoptosis-related drug resistance.

Design, synthesis, and biological evaluation of novel benzodiazepine derivatives as anticancer agents through inhibition of tubulin polymerization in vitro and in vivo.

A series of novel structurally-related tubulin polymerization inhibitors based on benzodiazepine were designed, synthesized, and evaluated for anticancer activity. Extensive structure modifications were performed to investigate the detailed structure and activity relationships (SARs). Most compounds exhibited potent antiproliferative activity against a panel of cancer cell lines. Among these compounds, the optimal compound, 9a, possessed the most superior activity, including cytotoxicity against five cancer cell lines (IC50 = 6-15 nM) and inhibition of tubulin polymerization (IC50 = 1.65 ±â€¯0.11 µM). Mechanistic studies revealed that 9a could disrupt intracellular microtubule organization, arrest cell cycle at the G2/M phase and eventually induce cell apoptosis. Compound 9a exhibited good metabolic stability with a t1/2 of 161.2 min, which was much better than the reference compound CA-4. Moreover, the disodium salt of 9a, 9a-P, exhibited excellent in vivo antitumor activity in xenograft mice model with inhibitory rate of 89.3%, which was better than the reference compounds CA-4P (inhibitory rate: 52.8%) and Y-01P (inhibitory rate: 77.7%). Altogether, 9a could serve as a promising lead compound for the development of highly efficient anticancer agents.

Selenepezil, a Selenium-Containing Compound, Exerts Neuroprotective Effect via Modulation of the Keap1-Nrf2-ARE Pathway and Attenuates Aß-Induced Cognitive Impairment in Vivo.

Oxidative stress is a major risk factor for neurodegenerative disease. The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2 related factor 2 (Nrf2)-antioxidant response element (ARE) pathway is one of the most potent defensive systems against oxidative stress. Selenepezil, a selenium-based compound, was previously found to exhibit excellent acetylcholinesterase (AChE) inhibition, to mimic endogenous glutathione peroxidase (GPx) activity, and to exhibit scavenging activity for hydrogen peroxide in vitro. However, none of these activities have been evaluated in a cellular model, and detailed molecular mechanisms are not elucidated. Moreover, whether selenepezil ameliorates memory deficits in vivo remains unknown. This study validated the cytoprotective effect of selenepezil against 6-hydroxydopamine (6-OHDA)- or H2O2-induced SH-SY5Y cell damage via alleviation or neutralization of intracellular microtubule disorder, reactive oxygen species (ROS) accumulation, mitochondrial dysfunction, and cell apoptosis. Our study clearly demonstrated that selenepezil pretreatment exhibited remarkable cytoprotective effect in a Nrf2-dependent manner via activating the Keap1-Nrf2-ARE pathway and stimulating the transcription of Nrf2-ARE-regulated cytoprotective genes. Moreover, selenepezil·HCl exerts neuroprotective effect via attenuating Aß-induced cognitive impairment in Alzheimer's disease (AD) rat and was more active than the reference drug donepezil. In summary, selenepezil deserves further consideration for AD therapy.

The discovery of a potent and selective third-generation EGFR kinase inhibitor as a therapy for EGFR L858R/T790M double mutant non-small cell lung cancer.

A new series of AZD9291 (osimertinib) derivatives containing a sulfoxide side chain at the C-4 position of an aniline moiety were designed, synthesized and evaluated. Among these derivatives, the chiral sulfoxide derivative (-)-4i exhibited excellent inhibition of EGFR kinase activity and L858R/T790M double mutant cell proliferation, with IC50 values of 4.10 nM and 10 nM, respectively. A mechanism study elucidated that (-)-4i induced cell apoptosis and reduced phosphorylation of EGFR and AKT in a dose-dependent manner. Furthermore, (-)-4i exhibited very little apparent toxicity toward three non-tumorigenic cell lines and was less toxic than AZD9291. Moreover, the remarkable exposure (AUC0-inf: 1294.74 h ng/mL), oral bioavailability (73.69%), and relatively shorter half-life (t1/2 = 1.12 h) of (-)-4i displayed its favorable pharmacokinetic properties. Finally, the antitumor activity of (-)-4i in vivo resulted in a significant reduction of the tumor volume (TGI: 94.30%). Altogether, these results suggest that (-)-4i warrants further investigation in Non-Small cell lung cancer (NSCLC) therapy.

Design, Synthesis, and Biological Evaluation of Novel Selenium-Containing Isocombretastatins and Phenstatins as Antitumor Agents.

Two series of structurally related organoselenium compounds designed by fusing the anticancer agent methyl(phenyl)selane into the tubulin polymerization inhibitors isocombretastatins or phenstatins were synthesized and evaluated for antiproliferative activity. Most of these selenium containing hybrids exhibited potent cytotoxicity against a panel of cancel cell lines, with IC50 values in the submicromolar concentration range. Among them, 11a, the 3-methylseleno derivative of isocombretastatin A-4 (isoCA-4) represented the most active compound with IC50 values of 2-34 nM against 12 cancer cell lines, including two drug-resistant cell lines. Importantly, its phosphate salt, 11ab, inhibited tumor growth in xenograft mice models with inhibitory rate of 72.9% without apparent toxicity, which was better than the reference compounds isoCA-4P (inhibitory rate 52.2%) and CA-4P (inhibitory rate 47.6%). Mechanistic studies revealed that 11a is a potent tubulin polymerization inhibitor, which could arrest cell cycle at G2/M phase and induce apoptosis along with the decrease of mitochondrial membrane potential. In summary, 11a could serve as a promising lead for the development of highly efficient anticancer agents.

A novel synthetic compound exerts effective anti-tumour activity in vivo via the inhibition of tubulin polymerisation in A549 cells.

Microtubules are critical elements that are involved in a wide range of cellular processes, and thus, they have become an attractive target for many anticancer drugs. A novel synthesised compound, 12P, was identified as new microtubule inhibitor. This compound inhibits tubulin polymerisation through binding to the colchicine-binding site of tubulin. 12P exhibits excellent anti-proliferative activities against a panel of human cancer cell lines, with IC50 values range from 9 to 55nM. Interestingly, compound 12P also displayed equally potent cytotoxicity against several drug-resistant cell lines, and it showed high selectivity for active human umbilical vein endothelial cells (HUVECs). Further flow cytometric analysis showed that 12P induces G2/M phase arrest and apoptosis in A549 cells. Cellular studies have revealed that the induction of apoptosis by 12P was associated with a collapse of mitochondrial membrane potential (MMP), accumulation of reactive oxygen species (ROS), alterations in the expression of some cell cycle-related proteins (e.g. Cyclin B1, Cdc25c, Cdc2) and some apoptosis-related proteins (e.g. Bax, Bad, Bcl-2, Bcl-xl). Importantly, 12P significantly reduced the growth of xenograft tumours of A549 cells in vivo (tumour inhibitory rate of 12P: 84.2%), without any loss of body weight. Taken together, these in vitro and in vivo results suggested that 12P may become a promising lead compound for the development of new anticancer drugs.