Explore the vast range of titles available.

The Hippo-YAP signaling pathway is a critical regulator of proliferation, apoptosis, and cell fate. The main downstream effector of this pathway, YAP, has been shown to be misregulated in human cancer and has emerged as an attractive target for therapeutics. A significant insufficiency in our understanding of the pathway is the identity of transcriptional targets of YAP that drive its potent growth phenotypes. Here, using liver cancer as a model, we identify NUAK2 as an essential mediator of YAP-driven hepatomegaly and tumorigenesis in vivo. By evaluating several human cancer cell lines we determine that NUAK2 is selectively required for YAP-driven growth. Mechanistically, we found that NUAK2 participates in a feedback loop to maximize YAP activity via promotion of actin polymerization and myosin activity. Additionally, pharmacological inactivation of NUAK2 suppresses YAP-dependent cancer cell proliferation and liver overgrowth. Importantly, our work here identifies a specific, potent, and actionable target for YAP-driven malignancies. Hippo-YAP pathway plays an important role in cancers; however the in vivo relevance of YAP/TAZ target genes is unclear. Here, the authors show that NUAK2 is a target of YAP and participates in a feedback loop to maximize YAP activity. Inhibition of NUAK2 suppresses YAP-driven hepatomegaly and liver cancer growth, offering a new target for cancer therapy.

Benzodiazepines are widely recognized for their therapeutic benefits in the treatment of anxiety and insomnia. However, in the pursuit of innovative anticancer agents, they have gained attention as a possible pharmacophore. One of those promising anticancer benzodiazepines is 3b which was demonstrated to exert good antiproliferative effects. To investigate the anticancer effect of 3b , in silico prediction of the possible targets were performed. Then, the predicted targets were investigated through in vitro study. Furthermore, 3b was evaluated for its effects on cell cycle suppression and induction of apoptosis. Molecular docking was used to study the possible types of interactions while molecular dynamics simulations were conducted to estimate the protein–ligand complex’s stability and dynamic behavior. Results demonstrated that 3b is a potent dual inhibitor of HER2 and HDAC1 with IC 50 values of 0.023 and 0.041 nM, respectively. Moreover, 3b was found to suppress cell cycle progression in G2/M phase and induce early and late apoptosis in HepG2 cancer cells. Further analysis of apoptotic markers revealed an induction of Caspase 3 and BAX proapoptotic proteins along with a suppression of the antiapoptotic protein (Bcl-2). Molecular docking of 3b into the active site of HER2 and HDAC1 displayed significant types of interactions with active sites of these target proteins while molecular dynamics simulations demonstrated the overall structural stability of HER2 and HDAC1 is maintained or even enhanced upon ligand binding. In conclusion, 3b is a powerful anticancer agent that exerts its effects by inhibiting HDAC1 and HER2, resulting in cell cycle arrest and cancer cell death through apoptosis. Nonetheless, additional investigations are needed to explore its mechanisms and therapeutic efficacy in more detail.

A potent and selective inhibitor of the kinase LRRK2 identified using an in vitro ATP-site competition binding assay also inhibits the G2019S mutant, implicated in Parkinson's disease, as well as the regulatory feedback loop where LRRK2 is phosphorylated and binds 14-3-3 protein. Mutations in leucine-rich repeat kinase 2 (LRRK2) are strongly associated with late-onset autosomal dominant Parkinson's disease. We employed a new, parallel, compound-centric approach to identify a potent and selective LRRK2 inhibitor, LRRK2-IN-1, and demonstrated that inhibition of LRRK2 induces dephosphorylation of Ser910 and Ser935 and accumulation of LRRK2 within aggregate structures. LRRK2-IN-1 will serve as a versatile tool to pharmacologically interrogate LRRK2 biology and study its role in Parkinson's disease.

Background Chk1 inhibitors are currently in clinical trials as putative potentiators of cytotoxic chemotherapy drugs. Chk1 inhibitors may exhibit single agent anti-tumor activity in cancers with underlying DNA repair, DNA damage response or DNA replication defects. Methods Here we describe the cellular effects of the pharmacological inhibition of the checkpoint kinase Chk1 by the novel inhibitor V158411 in triple-negative breast cancer and ovarian cancer. Cytotoxicity, the effect on DNA damage response and cell cycle along with the ability to potentiate gemcitabine and cisplatin cytotoxicity in cultured cells was investigated. Western blotting of proteins involved in DNA repair, checkpoint activation, cell cycle and apoptosis was used to identify potential predictive biomarkers of Chk1 inhibitor sensitivity. Results The Chk1 inhibitors V158411, PF-477736 and AZD7762 potently inhibited the proliferation of triple-negative breast cancer cells as well as ovarian cancer cells, and these cell lines were sensitive compared to ER positive breast and other solid cancer cells lines. Inhibition of Chk1 in these sensitive cell lines induced DNA damage and caspase-3/7 dependent apoptosis. Western blot profiling identified pChk1 (S296) as a predictive biomarker of Chk1 inhibitor sensitivity in ovarian and triple-negative breast cancer and pH2AX (S139) in luminal breast cancer. Conclusions This finding suggests that Chk1 inhibitors either as single agents or in combination chemotherapy represents a viable therapeutic option for the treatment of triple-negative breast cancer. pChk1 (S296) tumor expression levels could serve as a useful biomarker to stratify patients who might benefit from Chk1 inhibitor therapy.

Maintaining energy homeostasis requires complex feedback across organs that is difficult to study in isolated systems. New research uses whole-organism screening to identify key regulators of fasting metabolism in zebrafish, including ligands for the mitochondrial transporter protein TSPO. Improving the control of energy homeostasis can lower cardiovascular risk in metabolically compromised individuals. To identify new regulators of whole-body energy control, we conducted a high-throughput screen in transgenic reporter zebrafish for small molecules that modulate the expression of the fasting-inducible gluconeogenic gene pck1. We show that this in vivo strategy identified several drugs that affect gluconeogenesis in humans as well as metabolically uncharacterized compounds. Most notably, we find that the translocator protein ligands PK 11195 and Ro5-4864 are glucose-lowering agents despite a strong inductive effect on pck1 expression. We show that these drugs are activators of a fasting-like energy state and, notably, that they protect high-fat diet–induced obese mice from hepatosteatosis and glucose intolerance, two pathological manifestations of metabolic dysregulation. Thus, using a whole-organism screening strategy, this study has identified new small-molecule activators of fasting metabolism.

Translocator protein (TSPO) and voltage dependent anion channels (VDAC) are two proteins forming a macromolecular complex in the outer mitochondrial membrane that is involved in pleiotropic functions. Specifically, these proteins were described to regulate the clearance of damaged mitochondria by selective mitophagy in non-erythroid immortalized cell lines. Although it is well established that erythroblast maturation in mammals depends on organelle clearance, less is known about mechanisms regulating this clearance throughout terminal erythropoiesis. Here, we studied the effect of TSPO1 downregulation and the action of Ro5-4864, a drug ligand known to bind to the TSPO/VDAC complex interface, in ex vivo human terminal erythropoiesis. We found that both treatments delay mitochondrial clearance, a process associated with reduced levels of the PINK1 protein, which is a key protein triggering canonical mitophagy. We also observed that TSPO1 downregulation blocks erythroblast maturation at the orthochromatic stage, decreases the enucleation rate, and increases cell death. Interestingly, TSPO1 downregulation does not modify reactive oxygen species (ROS) production nor intracellular adenosine triphosphate (ATP) levels. Ro5-4864 treatment recapitulates these phenotypes, strongly suggesting an active role of the TSPO/VDAC complex in selective mitophagy throughout human erythropoiesis. The present study links the function of the TSPO/VDAC complex to the PINK1/Parkin-dependent mitophagy induction during terminal erythropoiesis, leading to the proper completion of erythroid maturation.

Background Doublecortin-like kinase 1 (DCLK1) is emerging as a tumor specific stem cell marker in colorectal and pancreatic cancer. Previous in vitro and in vivo studies have demonstrated the therapeutic effects of inhibiting DCLK1 with small interfering RNA (siRNA) as well as genetically targeting the DCLK1 + cell for deletion. However, the effects of inhibiting DCLK1 kinase activity have not been studied directly. Therefore, we assessed the effects of inhibiting DCLK1 kinase activity using the novel small molecule kinase inhibitor, LRRK2-IN-1, which demonstrates significant affinity for DCLK1. Results Here we report that LRRK2-IN-1 demonstrates potent anti-cancer activity including inhibition of cancer cell proliferation, migration, and invasion as well as induction of apoptosis and cell cycle arrest. Additionally we found that it regulates stemness, epithelial-mesenchymal transition, and oncogenic targets on the molecular level. Moreover, we show that LRRK2-IN-1 suppresses DCLK1 kinase activity and downstream DCLK1 effector c-MYC, and demonstrate that DCLK1 kinase activity is a significant factor in resistance to LRRK2-IN-1. Conclusions Given DCLK1’s tumor stem cell marker status, a strong understanding of its biological role and interactions in gastrointestinal tumors may lead to discoveries that improve patient outcomes. The results of this study suggest that small molecule inhibitors of DCLK1 kinase should be further investigated as they may hold promise as anti-tumor stem cell drugs.

Background White matter injury (WMI) is a major neuropathological event associated with intracerebral hemorrhage (ICH). P2X purinoreceptor 4 (P2X4R) is a member of the P2X purine receptor family, which plays a crucial role in regulating WMI and neuroinflammation in central nervous system (CNS) diseases. Our study investigated the role of P2X4R in the WMI and the inflammatory response in mice, as well as the possible mechanism of action after ICH. Methods ICH was induced in mice via collagenase injection. Mice were treated with 5-BDBD and ANA-12 to inhibit P2X4R and tropomyosin-related kinase receptor B (TrkB), respectively. Immunostaining and quantitative polymerase chain reaction (qPCR) were performed to detect microglial phenotypes after the inhibition of P2X4R. Western blots (WB) and immunostaining were used to examine WMI and the underlying molecular mechanisms. Cylinder, corner turn, wire hanging, and forelimb placement tests were conducted to evaluate neurobehavioral function. Results After ICH, the protein levels of P2X4R were upregulated, especially on day 7 after ICH, and were mainly located in the microglia. The inhibition of P2X4R via 5-BDBD promoted neurofunctional recovery after ICH as well as the transformation of the pro-inflammatory microglia induced by ICH into an anti-inflammatory phenotype, and attenuated ICH-induced WMI. Furthermore, we found that TrkB blockage can reverse the protective effects of WMI as well as neuroprotection after 5-BDBD treatment. This result indicates that P2X4R plays a crucial role in regulating WMI and neuroinflammation and that P2X4R inhibition may benefit patients with ICH. Conclusions Our results demonstrated that P2X4R contributes to WMI by polarizing microglia into a pro-inflammatory phenotype after ICH. Furthermore, the inhibition of P2X4R promoted pro-inflammatory microglia polarization into an anti-inflammatory phenotype, enhanced brain-derived neurotrophic factor (BDNF) production, and through the BDNF/TrkB pathway, attenuated WMI and improved neurological function. Therefore, the regulation of P2X4R activation may be beneficial for the reducing of ICH-induced brain injury.

In the course of screening lipopolysaccharide (LPS)-induced nitric oxide (NO) production inhibitors, two related benzodiazepine derivatives, cyclopenol and cyclopenin, were isolated from the extract of a deep marine-derived fungal strain, Aspergillus sp. SCSIOW2. Cyclopenol and cyclopenin inhibited the LPS-induced formation of NO and secretion of IL-6 in RAW264.7 cells at nontoxic concentrations. In terms of the mechanism underlying these effects, cyclopenol and cyclopenin were found to inhibit the upstream signal of NF-κB activation. These compounds also inhibited the expression of IL-1β, IL-6, and inducible nitric oxide synthase (iNOS) in mouse microglia cells, macrophages in the brain. In relation to the cause of Alzheimer’s disease, amyloid-β-peptide is known to induce inflammation in the brain. Therefore, the present study investigated the ameliorative effects of these inhibitors on an in vivo Alzheimer’s model using flies. Learning deficits were induced by the overexpression of amyloid-β42 in flies, and cyclopenin but not cyclopenol was found to rescue learning impairment. Therefore, novel anti-inflammatory activities of cyclopenin were identified, which may be useful as a candidate of anti-inflammatory agents for neurodegenerative diseases.

Several new (5-aryloxy-pyrazolyl)- and (5-aryl/olefin-sulfanyl-pyrazolyl)-dibenzo[b,e] [1,4] diazepinone scaffolds have been synthesized, by assembling 5-substituted 3-methyl-1-phenyl-pyrazole-4-carbaldehydes of varied nature with different cyclic diketones and aromatic diamines successfully in the presence of indium chloride in acetonitrile, at room temperature. Desired products are excellent in the purity and isolated without chromatography. All new structures are confirmed, on the basis of single-crystal X-ray diffraction data of representative 29e. Compounds reported in the present work revealed good antioxidant, antimicrobial and antiproliferative activities with promising FRAP (ferric reducing antioxidant power), bacterial resistance and human solid tumor cell growth inhibitory values, respectively. Compounds 25c and 29e, overall, registered good to moderate activity against A549 (lung), HeLa (cervix), SW1573 (lung) T-47D (breast) and WiDr (colon) cell lines, with GI50 values in the 2.6–5.1 μM and 1.8–7.5 μM ranges, respectively. Molecular docking was carried out to elucidate the binding modes of the compounds (25c, 29e) to topoisomerase I and II.