Inhibition Of Activity Research Articles

Dual VEGFR-2 and EGFRT790M inhibitors of phenyldiazenes: anticancer evaluations, ADMET, docking, design and synthesis.

New phenyldiazene scaffold-linked heterocyclic pyrazole, pyrimidinone, pyrimidinthione, and/or triazine rings have been developed and synthesized. Cytotoxicity of our derivatives was estimated on four cancer and VERO normal cell lines targeting EGFRT790M (epidermal growth factor receptor) and VEGFR-2 (vascular endothelial growth factor receptor-2) enzymes. Our new derivatives selectively inhibited both VEGFR-2 and EGFR as they have the essential structural requirements for inhibitors of both receptors. Derivative 14 was the most active on A549, HCT116, HepG2, and MCF-7 cancers with half-maximal inhibitory concentration (IC50) = 5.50, 9.77, 7.12, and 7.85 µM respectively. The assessed derivatives 5, 7, 8, 9, 10, 12 and 14 showed IC50 = 54.40-62.60 μM against normal VERO (normal kidney) cells with low toxicity. In addition, derivatives 14, 8, 10, 7 and 9 were discovered to be very good active inhibitors of VEGFR-2 at IC50 values of 1.15, 1.35, 140, 1.78 and 1.90 µM, respectively. Furthermore, derivatives 14, 10, 8, and 9 strongly repressed EGFRT790M with IC50 = 0.28, 0.33, 0.35, and 0.50 µM correspondingly. Additionally, the highly active compounds 8, 10, and 14 showed good ADMET profile. Our derivatives could be considered as anticancer agents with dual VEGFR-2 and EGFRT790M inhibition.

Advancing COVID-19 Treatment: The Role of Non-covalent Inhibitors Unveiled by Integrated Machine Learning and Network Pharmacology.

The COVID-19 pandemic has necessitated rapid advancements in therapeutic discovery. This study presents an integrated approach combining machine learning (ML) and network pharmacology to identify potential non-covalent inhibitors against pivotal proteins in COVID-19 pathogenesis, specifically B-cell lymphoma 2 (BCL2) and Epidermal Growth Factor Receptor (EGFR). Employing a dataset of 13,107 compounds, ML algorithms such as k-Nearest Neighbors (kNN), Support Vector Machine (SVM), Random Forest (RF), and Naïve Bayes (NB) were utilized for screening and predicting active inhibitors based on molecular features. Molecular docking and molecular dynamics simulations, conducted over a 100 nanosecond period, enhanced the ML-based screening by providing insights into the binding affinities and interaction dynamics with BCL2 and EGFR. Network pharmacology analysis identified these proteins as hub targets within the COVID-19 protein-protein interaction network, highlighting their roles in apoptosis regulation and cellular signaling. The identified inhibitors exhibited strong binding affinities, suggesting potential efficacy in disrupting viral life cycles and impeding disease progression. Comparative analysis with existing literature affirmed the relevance of BCL2 and EGFR in COVID-19 therapy and underscored the novelty of integrating network pharmacology with ML. This multidisciplinary approach establishes a framework for emerging pathogen treatments and advocates for subsequent in vitro and in vivo validation, emphasizing a multi-targeted drug design strategy against viral adaptability. This study's findings are crucial for the ongoing development of therapeutic agents against COVID-19, leveraging computational and network-based strategies.

A Novel, Cell-Compatible Hyaluronidase Activity Assay Identifies Dextran Sulfates and Other Sulfated Polymeric Hydrocarbons as Potent Inhibitors for CEMIP

Hyaluronan (HA) levels are dynamically regulated homeostatically through biosynthesis and degradation. HA homeostasis is often perturbed under disease conditions. HA degradation products are thought to contribute to disease pathology. The hyaluronidase CEMIP requires the presence of living cells for its HA depolymerizing activity. CEMIP is overexpressed in a variety of pathological conditions, and the inhibition of its hyaluronidase activity therefore has therapeutic potential. To identify novel inhibitors of the CEMIP hyaluronidase activity, we established here a cell-compatible, medium-throughput assay for CEMIP-dependent HA depolymerization. The assay employs ultrafiltration plates to separate low- from high-molecular-weight HA, followed by quantification of HA fragments using an HA ELISA-like assay. Using this assay, we tested a range of compounds that have been reported to inhibit other hyaluronidases. Thereby, we identified several sulfated hydrocarbon polymers that inhibit CEMIP more potently than other hyaluronidases. One of these is heparin, a sulfated glycosaminoglycan produced by mast cells that constitutes the first described physiological CEMIP inhibitor. The most potent inhibitor (IC50 of 1.8 nM) is dextran sulfate, a synthetic sulfated polysaccharide. Heparin and dextran sulfate are used in numerous established and experimental biomedical applications. Their ability to inhibit CEMIP needs to be taken into account in these contexts.

Hepatitis B virus hijacks MRE11-RAD50-NBS1 complex to form its minichromosome.

Chronic hepatitis B virus (HBV) infection can significantly increase the incidence of cirrhosis and liver cancer, and there is no curative treatment. The persistence of HBV covalently closed circular DNA (cccDNA) is the major obstacle of antiviral treatments. cccDNA is formed through repairing viral partially double-stranded relaxed circular DNA (rcDNA) by varies host factors. However, the detailed mechanisms are not well characterized. To dissect the biogenesis of cccDNA, we took advantage of an in vitro rcDNA repair system to precipitate host factors interacting with rcDNA and identified co-precipitated proteins by mass spectrometry. Results revealed the MRE11-RAD50-NBS1 (MRN) complex as a potential factor. Transiently or stably knockdown of MRE11, RAD50 or NBS1 in hepatocytes before HBV infection significantly decreased viral markers, including cccDNA, while reconstitution reversed the effect. Chromatin immunoprecipitation assay further validated the interaction of MRN complex and HBV DNA. However, MRN knockdown after HBV infection showed no effect on viral replication, which indicated that MRN complex inhibited the formation of cccDNA without affecting its stability or transcriptional activity. Interestingly, Mirin, a MRN complex inhibitor which can inhibit the exonuclease activity of MRE11 and MRN-dependent activation of ATM, but not ATM kinase inhibitor KU55933, could decrease cccDNA level. Likewise, the MRE11 endonuclease activity inhibitor PFM01 treatment decreased cccDNA. MRE11 nuclease assays indicated that rcDNA is a substrate of MRE11. Furthermore, the inhibition of ATR-CHK1 pathway, which is known to be involved in cccDNA formation, impaired the effect of MRN complex on cccDNA. Similarly, inhibition of MRE11 endonuclease activity mitigated the effect of ATR-CHK1 pathway on cccDNA. These findings indicate that MRN complex cooperates with ATR-CHK1 pathway to regulate the formation of HBV cccDNA. In summary, we identified host factors, specifically the MRN complex, regulating cccDNA formation during HBV infection. These findings provide insights into how HBV hijacks host enzymes to establish chronic infection and reveal new therapeutic opportunities.

Exploring oncogenic roles and clinical significance of EZH2: focus on non-canonical activities.

The enhancer of zeste homolog 2 (EZH2) is a catalytic component of Polycomb repressive complex 2 (PRC2) mediating the methylation of histone 3 lysine 27 (H3K27me3) and hence the epigenetic repression of target genes, known as canonical function. Growing evidence indicates that EZH2 has non-canonical roles that are exerted as PRC2-dependent and PRC2-independent methylation of non-histone proteins, and methyltransferase-independent interactions of EZH2 with various proteins contributing to gene expression regulation and alterations in the protein stability. EZH2 is frequently mutated and/or its expression is deregulated in various cancer types. The cancer sensitivity to inhibitors of EZH2 enzymatic activity and state-of-the-art approaches to deplete EZH2 with chemical degraders are discussed. This review also presents the clinical trials in various phases that evaluate the use of EZH2 inhibitors, both as monotherapy and in combination with other agents for the treatment of patients with diverse types of cancers.

A high throughput assay for phosphoribosylformylglycinamidine synthase.

Metabolic reprogramming of purine biosynthesis is a hallmark of cancer metabolism and represents a critical vulnerability. The enzyme phosphoribosylformylglycinamidine synthase (PFAS) catalyzes the fourth step in de novo purine biosynthesis and has been demonstrated to be prognostic for survival of liver cancer. Despite the importance of this protein as a drug target, there are no known specific inhibitors of PFAS activity. Here, we describe a new continuous, spectrophotometric assay for the synthase domain of PFAS that is amenable to high-throughput screening (HTS). This mechanism-based fluorescent assay makes use of the acid phosphatase substrate, 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP). PFAS catalyzes the turnover of DiFMUP with a KM of 108 ± 7 µM. After optimization and miniaturization of the assay for 1,536-well format, we conducted a pilot HTS using the LOPAC1280 library. The assay performed extremely well, with an average Z´ of 0.94 ± 0.02, average signal to noise of 5.01 ± 0.06, excellent inter plate correlation, and a hit rate of 1.18%. This assay provides a critically needed tool to advance the study of PFAS enzymology and will be foundational for the discovery of small molecule inhibitors both as functional probes and for the basis of new drug development.

A review of the role of bioactive components in legumes in the prevention and treatment of cardiovascular diseases.

Cardiovascular diseases (CVD) represent a primary global health challenge. Poor dietary choices and lifestyle factors significantly increase the risk of developing CVD. Legumes, recognized as functional foods, contain various bioactive components such as active peptides, protease inhibitors, saponins, isoflavones, lectins, phytates, and tannins. Studies have demonstrated that several of these compounds are associated with the prevention and treatment of cardiovascular diseases, notably active peptides, saponins, isoflavones, and tannins. This review aims to analyze and summarize the relationship between bioactive compounds in legumes and cardiovascular health. It elaborates on the mechanisms through which active ingredients in legumes interact with risk factors for cardiovascular diseases, such as hypertension, hypercholesterolemia, endothelial dysfunction, and atherosclerosis. These mechanisms include, but are not limited to, lowering blood pressure, regulating lipid levels, promoting anticoagulation, enhancing endothelial function, and modulating TLR4 and NF-κB signaling pathways. Together, these mechanisms emphasize the potential of legumes in improving cardiovascular health. Additionally, the limitations of bioactive components in legumes and their practical applications, with the goal of fostering further advancements in this area were discussed.

Identification of Lauric Acid as a Potent Sodium Channel NaV1.5 Blocker from Compound Chinese Medicine Wenxin Keli.

The major cardiac voltage-gated sodium channel NaV1.5 (INa) is essential for cardiac action potential initiation and subsequent propagation. Compound Chinese medicine Wenxin Keli (WXKL) has been shown to suppress arrhythmias and heart failure. However, its active components have not been fully elucidated. This study focused on identifying the active inhibitor of INa in WXKL and exploring their mode of action in electrophysiological conduction. A chemical fraction library was constructed from an aqueous extract of WXKL and screened using an automated patch-clamping system in cells stably expressing the NaV1.5 gene SCN5A. Candidate fractions with INa-inhibition activity were analyzed by HPLC-ESI-IT-TOF-MS and GC-MS to identify the ingredients. NaV1.5 blocker molecules identified by single-cell electrocardiogram were tested in hiPSC-derived cardiomyocytes. We evaluated the SCN5A inhibitory potential of Wenxin Keli effective monomer employing molecular docking and molecular dynamics simulation approaches. A primary screen of the WXKL chemical library identified five fractions that significantly inhibited the NaV1.5 channel, with one of them rich in poly-saturated fatty acids. Molecular structural characterization revealed the presence of lauric acid, myristic acid, palmitic acid, and stearic acid in the active subfraction. Electrophysiological characterization demonstrated lauric acid (LA) as the most effective monomer for INa-inhibition with an IC50 at 27.40 ± 12.78 μM. LA shifted the steady-state inactivation of INa to more negative potentials and decreased the amplitude of extracellular field potential in hiPSC-derived cardiomyocytes. We demonstrate for the first time that naturally poly-saturated fatty acid, lauric acid, as a potential novel INa blocker. Molecular docking and molecular dynamics simulation suggested that LA binds to the NaV1.5 protein, with a significant binding affinity forming interactions with functionally essential residues and blocks the inward flow of Na+. Mechanistically, lauric acid acts on the fast inactivation of NaV1.5 alter electrophysiology conduction of hiPSC-derived cardiomyocytes and contribute to the antiarrhythmic effect of WXKL. Lauric acid is a potent blocker for sodium channel NaV1.5 and alleviates arrhythmia via inhibiting INa.

Discovery of Triketone-Indazolones as Novel 4-Hydroxyphenylpyruvate Dioxygenase Inhibiting-Based Herbicides.

4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a crucial herbicide target in current research, playing an important role in the comprehensive management of resistant weeds. However, the limited crop selectivity and less effectiveness against grass weeds of many existing HPPD inhibitors, limit their further application. To address these issues, a series of novel HPPD inhibitors with fused ring structures were designed and synthesized by introducing an electron-rich indazolone ring and combining it with the classical triketone pharmacophore structure. The cocrystal structure of representative compound III-7 complexed with Arabidopsis thaliana HPPD (AtHPPD) was obtained at 2.0 Å resolution to guide the optimization of the designed inhibitor. The optimization results showed that 5-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,4-dimethyl-2-(3-(methylthio)phenyl)-1,2-dihydro-3H-indazol-3-one, III-15, was the most active AtHPPD inhibitor, with an IC50 value of 12 nM, nearly 30 times higher efficacy than mesotrione. Greenhouse herbicidal activity tests demonstrated that compound III-15 exhibited excellent herbicidal potency at 30-120 g ai/ha. Notably, it maintained high safety for peanuts even at 120 g ai/ha. Our results showed that compound III-15 is promising as a new candidate HPPD herbicide for use in the peanut fields.

Inhibiting CFTR through inh-172 in primary neutrophils reveals CFTR-specific functional defects

The lungs of people with cystic fibrosis (PwCF) are characterized by recurrent bacterial infections and inflammation. Infections in cystic fibrosis (CF) are left unresolved despite excessive neutrophil infiltration. The role of CFTR in neutrophils is not fully understood. In this study, we aimed to assess which antimicrobial functions are directly impaired by loss of CFTR function in neutrophils. In order to do so, we used a specific inhibitor of CFTR ion channel activity, inh-172. CF neutrophils from PwCF harboring severe CFTR mutations were additionally isolated to further discern CFTR-specific functional defects. We evaluated phagocytosis, reactive oxygen species (ROS) production, neutrophil elastase (NE) and myeloperoxidase (MPO) exocytosis and bacterial killing. The inh-172 model identified decreased acidification of the phagosome, increased bacterial survival and decreased ROS production upon stimulation. In PwCF neutrophils, we observed reduced degranulation of both NE and MPO. When co-culturing neutrophils with CF sputum supernatant and airway epithelial cells, the extent of phagocytosis was reduced, underscoring the importance of recreating an inflammatory environment as seen in PwCF lungs to model immune responses in vitro. Despite low CFTR expression in blood neutrophils, functional defects were found in inh-172-treated and CF neutrophils. The inh-172 model disregards donor variability and allows pinpointing neutrophil functions directly impaired by dysfunctional CFTR.

Impact of the clinically approved BTK inhibitors on the conformation of full-length BTK and analysis of the development of BTK resistance mutations in chronic lymphocytic leukemia

Inhibition of Bruton’s tyrosine kinase (BTK) has proven to be highly effective in the treatment of B-cell malignancies such as chronic lymphocytic leukemia (CLL), autoimmune disorders, and multiple sclerosis. Since the approval of the first BTK inhibitor (BTKi), Ibrutinib, several other inhibitors including Acalabrutinib, Zanubrutinib, Tirabrutinib, and Pirtobrutinib have been clinically approved. All are covalent active site inhibitors, with the exception of the reversible active site inhibitor Pirtobrutinib. The large number of available inhibitors for the BTK target creates challenges in choosing the most appropriate BTKi for treatment. Side-by-side comparisons in CLL have shown that different inhibitors may differ in their treatment efficacy. Moreover, the nature of the resistance mutations that arise in patients appears to depend on the specific BTKi administered. We have previously shown that Ibrutinib binding to the kinase active site causes unanticipated long-range effects on the global conformation of BTK (Joseph et al., 2020). Here, we show that binding of each of the five approved BTKi to the kinase active site brings about distinct allosteric changes that alter the conformational equilibrium of full-length BTK. Additionally, we provide an explanation for the resistance mutation bias observed in CLL patients treated with different BTKi and characterize the mechanism of action of two common resistance mutations: BTK T474I and L528W.

The role and clinical implications of HIF-PHI daprodustat in dialysis-dependent and non-dialysis-dependent chronic kidney disease anemic patients: a general review

Chronic kidney disease (CKD) patients often suffer from complications such as anemia as the kidney function declines. More than 25% of CKD hemodialysis patients in China are complicated with renal anemia due to renal and hepatic impairment in the production of erythropoietin (EPO). In recent years, prolyl hydroxylase domain (PHD) inhibitors have been approved in China and Japan for the treatment of CKD patients complicated with anemia. Daprodustat is a novel orally administrated active hypoxia-induced factor-prolyl hydroxylase inhibitor (HIF-PHI) that may improve quality of life and ischemic conditions such as peripheral arterial disease (PAD), stimulate the synthesis of endogenous EPO, and can effectively induce the production of red blood cells. It has been shown to increase EPO levels, which can lead to an increase in hemoglobin (Hgb), hematocrit, and red blood cell counts. Clinical studies have shown its effectiveness in dialysis and non-dialysis CKD anemic patients. In this literature review, we will focus on the mechanism and metabolism of the drug as well as its clinical applications in dialysis and non-dialysis CKD patients and summarize the adverse reactions.

The effect of synergists on the inhibition of detoxification enzyme activities and acaricide sensitivity in Rhizoglyphus robini.

The saffron bulb mite, Rhizoglyphus robini Claparede (Acari: Acaridae), is the most important pest of the saffron crop in Iran. This pest attacks and feeds on saffron corms. For this reason, the corms are treated with acaricides before planting. The high activity of detoxification enzymes in arthropods may reduce their pesticide sensitivity. Diethyl maleate (DEM) is an inhibitor of glutathione S-transferases (GSTs), piperonyl butoxide (PBO) is an inhibitor of cytochrome P450 monooxygenases, and triphenyl phosphate (TPP) is an inhibitor of esterase activity. A filter paper method was used to determine the efficiency of these synergists in inhibiting the activity of detoxifying enzymes of R. robini. Adult mites were treated with these three synergists for 6, 12, 24, and 48 h, respectively. The activity of each detoxifying enzyme was measured and compared to the control treatment, and the inhibition percentage was calculated each time. The results showed that DEM reduced GST activity by 59.9% after 48 h, PBO inhibited cytochrome P450 activity by 30%, and TPP suppressed esterase activity by 38.5%. The most statistically significant inhibition occurred 24 h after pretreatment with each synergist. Bioassays with 24 h pretreatment showed that the sensitivity of R. robini to propargite increased by 1.6 times with PBO, 1.7 times with TPP, and 2.5 times with DEM. In conclusion, synergists and efficient inhibition of detoxifying enzymes can play a significant role in increasing the sensitivity of agricultural pests to pesticides and can be considered in managing pesticide resistance.

Computational insights into potent USP5 inhibitors based on multistep virtual screening and molecular dynamics simulation

USP5 is widely distributed in various malignant tumors and can regulate the stability and promoting tumor progression of many tumor-related proteins. However, there is still a lack of highly active USP5 inhibitors. Therefore, effective inhibitors were screened in the TCMIO database in this study. Three hit compounds, CHEMBL3645368, CHEMBL3689818, and CHEMBL2070208, were finally obtained by molecular docking, molecular fingerprint, quantum chemistry, and molecular dynamics simulation. Molecular docking results showed hit compounds had similar binding mode comparing with positive compound. Quantum chemistry and molecular dynamics results showed hit compounds had better binding energy and higher affinity than the positive compound. ADMET predicted hit compounds had low toxicity. These results all suggest CHEMBL3645368, CHEMBL3689818, and CHEMBL2070208 may inhibit USP5 and could be candidates for further exploration.

Bichromatic Splicing Detector Allows Quantification of THRA1 and THRA2 Splicing Isoforms in Single Cells by Fluorescent Live-Cell Imaging.

Thyroid hormone receptor alpha (THRα) is a nuclear hormone receptor that binds triiodothyronine (T3) and acts as an important transcription factor in development, metabolism, and reproduction. The coding gene, THRA, has two major splicing isoforms in mammals, THRA1 and THRA2, which encode THRα1 and THRα1, respectively. The better characterized isoform, THRα1, is a transcriptional stimulator of genes involved in cell metabolism and growth. The less well-characterized isoform, THRα2, lacks the ligand-binding domain (LBD) and may act as an inhibitor of THRα1 activity. Thus, the ratio of THRα1 to THRα2 isoforms is critical for transcriptional regulation in various tissues and during development and may be abnormal in a number of thyroid hormone resistance syndromes. However, the complete characterization of the THRα isoform expression pattern in healthy human tissues, and especially the study of changes in the ratio of THRα1 to THRα2 in cultured patient cells, has been hampered by the lack of suitable tools to detect the isoform-specific expression patterns. Therefore, we developed a plasmid pCMV-THRA-RFP-EGFP splicing detector that allows the visualization and quantification of the differential expression of THRA1 and THRA2 splicing isoforms in living single cells during time-lapse and perturbation experiments. This tool enables experiments to further characterize the role of THRα2 and to perform high-throughput drug screening. Molecules that modify THRA splicing may be developed into drugs for the treatment of thyroid hormone resistance syndromes.

In Vitro and In Silico Evaluation of Syzygium aromaticum Essential Oil: Effects on Mitochondrial Function and Cytotoxic Potential Against Cancer Cells.

The current study proposes the in vitro and in silico anticancer evaluation of clove (Syzygium aromaticum L.) essential oil (CEO). The steam hydrodistillation method used yielded 10.7% (wt) CEO. GC-MS analysis revealed that the obtained oil is rich in eugenol (75%), β-caryophyllene (20%), and α- caryophyllene (2.8%) and also contains several other minor components accounting for approximately 1.5%. The DPPH-based scavenging antioxidant activity was assessed for the obtained CEO, exhibiting an IC50 value of 158 μg/mL. The cytotoxic effects of CEO, its major component eugenol, and CEO solubilized with Tween-20 and PEG-400 were tested against both noncancerous HaCaT cells and HT-29 human colorectal adenocarcinoma, RPMI-7951 melanoma, A431 skin carcinoma, and NCI-H460 non-small lung cancer cells, using the Alamar Blue and LDH assay after 48 h treatment. The Tween-20 and PEG-400 CEO formulations, at 200 μg/mL, recorded the highest cytotoxic and selective effects against RPMI-7951 (72.75% and 71.56%), HT-29 (71.51% and 45.43%), and A431 cells (61.62% and 59.65%). Furthermore, CEO disrupted mitochondrial function and uncoupled oxidative phosphorylation. This effect was more potent for the CEO against the RPMI-7951 and HT-29 cells, whereas for the other two tested cell lines, a more potent inhibition of mitochondrial function was attributed to eugenol. The present study is the first to specifically investigate the effects of CEO and Tween-20 and PEG-400 CEO formulations on the mitochondrial function of RPMI-7951, HT-29, A431, and NCI-H460 cancer cell lines using high-resolution respirometry, providing novel insights into their impact on mitochondrial respiration and bioenergetics in cancer cells. The results obtained may explain the increased ROS production observed in cancer cell lines treated with eugenol and CEO. Molecular docking identified potential protein targets, related to the CEO anticancer activity, in the form of PI3Kα, where the highest active theoretical inhibitor was calamenene (-7.5 kcal/mol). Docking results also showed that calamenene was the overall most active theoretical inhibitor for all docked proteins and indicated a potential presence of synergistic effects among all CEO constituents.

DTX3L-mediated TIRR nuclear export and degradation regulates DNA repair pathway choice and PARP inhibitor sensitivity

53BP1 plays an important role in DNA double-strand break (DSB) repair and this activity is negatively regulated by its interaction with Tudor interacting repair regulator (TIRR). However, how the TIRR-53BP1 repair axis is regulated in response to DNA damage remains elusive. Here, we demonstrate that TIRR is translocated to the cytoplasm and degraded upon DNA damage. Ubiquitination of TIRR at lysine 187 by DTX3L is a critical process that regulates NHEJ pathway activity and PARP inhibitor sensitivity by facilitating XPO1-mediated TIRR nuclear export and degradation after DNA damage. We show that DTX3L is overexpressed in prostate cancers in patients and that decreased expression of TIRR due to DTX3L overexpression impairs the negative regulatory effect of TIRR on 53BP1, which consequently induces HR deficiency and chromosomal instability and sensitizes prostate cancer cells to poly (ADP-ribose) polymerase (PARP) inhibitors. Our work reveals a dual action of DTX3L on TIRR degradation and nuclear exportation and identifies DTX3L as an upstream regulator of the TIRR-53BP1 axis that governs DNA repair pathway choice and PARP inhibitor sensitivity. These findings suggest that TIRR ubiquitination and DTX3L overexpression could be viable biomarkers predicting PARP inhibitor sensitivity in cancers.

Prognostic and diagnostic value of SPINK mRNAs expression in head and neck squamous cell carcinoma based on genome-wide analysis

Aim: Head and neck squamous cell carcinoma (HNSC) is a major contributor to the global cancer burden. The serine protease inhibitor Kazal-type (SPINK) gene family has been linked to various cancers. This study explores the prognostic value of SPINK genes in predicting overall survival (OS) in HNSC patients. Methods: We analyzed RNA sequencing and clinical data from 504 cancer and 44 non-cancer samples from the TCGA database. Differential expression and functional enrichment analyses gene ontology and Kyoto encyclopedia of genes and genomes (GO and KEGG) were performed using clusterProfiler. Protein-protein interaction (PPI) networks were built with STRING and visualized. Immune infiltration was evaluated using single-sample Gene Set Enrichment Analysis (ssGSEA). Survival analysis utilized Kaplan-Meier curves and Cox regression models. Results: Our results showed that SPINK5, SPINK7, SPINK8, SPINK9, and SPINK14 were significantly overexpressed in normal tissues compared to carcinoma tissues, whereas SPINK1, SPINK4, and SPINK6 showed higher expression in carcinoma tissues. Correlation analysis revealed significant relationships among SPINK family members. GO and KEGG analyses highlighted their involvement in processes such as negative regulation of peptidase activity and serine-type endopeptidase inhibitor activity. PPI network analysis indicated close interactions between several SPINK proteins and other relevant proteins. Immune infiltration analysis showed that NK cells and Th2 cells were negatively correlated with SPINK genes, while mast cells and neutrophils were positively correlated. Survival analysis revealed that high mRNA expression levels of SPINK1, SPINK5, and SPINK6 were significantly associated with OS in HNSC patients. Receiver operating characteristic (ROC) curve analysis indicated that these genes have diagnostic value. We developed a nomogram model that combines tumor stage and SPINK gene expression providing a predictive tool for patient prognosis. Conclusions: This study elucidates the multifaceted roles of the SPINK gene family in HNSC. These findings offer valuable insights into their potential as diagnostic biomarkers and therapeutic targets.

Synthesis of Some Novel 4-bromobenzoic Acid Clubbed Hydrazone Schiff Base Derivatives as Potent α-amylase Inhibitors: In vitro and In silico Studies

Aims: Synthesis of novel 4-bromobenzoic acid-based hydrazone-Schiff base derivatives and to screen them for their α-amylase inhibitory activity. Objective: The biological activities of hydrazone-Schiff base compounds encouraged us to evaluate the synthesized derivatives (4-32) for in-vitro inhibition activity against the α-amylase enzyme. Methods: In current research work twenty-nine Schiff base derivatives (4-32) of 4-bromobenzoic acid were synthesized in worthy yields by treating various replaced aldehydes with 4- bromobenzohydrazide using methanol solvent in catalytic quantity of acetic acid. The products were structurally described through the support of several spectroscopic methods (EI-MS and 1HNMR) and finally evaluated against α-amylase enzyme. Results: All the made derivatives exhibited worthy inhibition potential from IC50 = 0.21 ± 0.01 to 5.50 ± 0.01 μM when equated to the usual acarbose drug having IC50 = 1.34 ± 0.01 μM. Compound 21 (IC50 = 0.21 ± 0.01 μM) was established as the most active inhibitor among the series better than standard. The structure-activity relationship study showed that the alteration in the activity of the produced products might be due to the attached position and nature of the substituents. Furthermore, in-silico study supported the effects of groups attached on the binding interaction with α-amylase enzyme. Conclusion: A series of substituted hydrazone Schiff bases based on 4-bromobenzoic acid were produced, confirmed the structures by EI-MS and 1H-NMR spectroscopic methods and lastly tested for their in-vitro α-amylase inhibitory potential. Among the series, twenty-four products indicated brilliant inhibition potential having IC50 values from 0.21 ± 0.01 to 1.30 ± 0.01 μM. The structure-activity relationship study showed that the alteration in the activity of the synthesized products might be due to the attached position and nature of the substituents. On the other hand, in silico studies advocated that the synthesized Schiff base derivatives have prevalent interactions of binding within the active site of the α-amylase enzyme, and because of their various attached substituent, their conformation is altered in the active site of the enzyme. The current study recognized a number of lead candidates derived from 4-bromobenzoic acid. Additional investigation of the synthesized derivatives for coming research to get novel α-amylase inhibitors.

Ex-vivo antioxidant, enzyme inhibitory properties and computational analysis unveil the molecular mechanism of cardiac and penile phosphodiesterase-5 inhibition by bacterial strain HOKA1 extract as an aphrodisiac's agent.

The study uses in-vitro antioxidant, ex-vivo enzyme kinetics and in-silico approach using standard protocols to understand their inhibitory mechanism better. The study revealed that bacterial strain HOKA1 isolated from Oniru beach, grown in nutrient agar supplemented with sodium chloride (30%NaCl). Moreso, the bacterial strain HOKA1 extract showed better antioxidant capability and greatly reduced the penile and cardiac cGMP with the highest penile and cardiac concentration between 0.013 and 0.183μM/Min as compared to the sildenafil citrate (0.00-0.203μM/Min). Moreover, the kinetic parameters (Vmax and Km) effects revealed that bacterial strain HOKA1 extract inhibited PDE-5 activities better than sildenafil citrate. The GC-MS analysis revealed twenty-nine bioactive compounds in the extract, and these compounds could provide comprehensible supporting evidence for the antioxidant and inhibitory potential of the strain HOKA1 extract on PDE-5 activity. Molecular docking study revealed majority of the GC-MS-identified bioactive constituents from the HOKA1 extract showed high binding energy or lower bonding affinities (-6.8 to -3.3kcal/mol) compared to reference drug sildenafil citrate (-9.6kcal/mol), except campesterol (-10.0kcal/mol); also, ergostane (-9.9kcal/mol). The results of 100ns simulation (RMSF, RMSD, Rg and H-bond) show extraordinary stability of PDE-5 with campesterol and ergostane, so also complimentary binding energy of MM-PBSA (campesterol -65.92±4.09kcal/mol; ergostane -57.23±4.70kcal/mol) indicating their probability of acting promising PDE-5 inhibitors. Therefore, the study revealed that bacterial strain HOKA1 extract showed a better aphrodisiac property, and its bioactive compounds (campesterol and ergostane) should be considered in upcoming rational development and design of more active selective PDE-5 inhibitors, making a treatment for erectile dysfunction.