Screening and bioinformatics analysis of key autophagy-related genes in alcoholic hepatitis / 器官移植

Objective To screen key autophagy-related genes in alcoholic hepatitis (AH) and investigate potential biomarkers and therapeutic targets for AH. Methods Two AH gene chips in Gene Expression Omnibus (GEO) and autophagy-related data sets obtained from MSigDB and GeneCards databases were used, and the key genes were verified and obtained by weighted gene co-expression network analysis (WGCNA). The screened key genes were subject to gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), protein-protein interaction (PPI) and immune infiltration analyses. Messenger RNA (mRNA)- microRNA (miRNA) network was constructed to analyze the expression differences of key autophagy-related genes during different stages of AH, which were further validated by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) in the liver tissues of AH patients and mice. Results Eleven autophagy-related genes were screened in AH (EEF1A2, CFTR, SOX4, TREM2, CTHRC1, HSPB8, TUBB3, PRKAA2, RNASE1, MTCL1 and HGF), all of which were up-regulated. In the liver tissues of AH patients and mice, the relative expression levels of SOX4, TREM2, HSPB8 and PRKAA2 in the AH group were higher than those in the control group. Conclusions SOX4, TREM2, HSPB8 and PRKAA2 may be potential biomarkers and therapeutic targets for AH.

Identification of key immune related genes in diabetes retinopathy based on weighted gene co-expression network / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the key genes related to immunity and immune cell infiltration levels in diabetes retinopathy(DR)using bioinformatics.METHODS: Differential expression genes(DEGs)were obtained by “limma” R from Gene Expression Omnibus(GEO)data from September to October 2022, Gene ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)were analyzed, and the infiltration of immune cell types in each sample was calculated based on CIBERSORT algorithm. Weighted gene co-expression network analysis(WGCNA)was used to screen for DEGs in immune-related gene modules. The protein-protein interaction(PPI)network was established by STRING online database and Cytoscape, and the hub genes were screened by MCODE and cytoHubba plug-ins.RESULTS: The results showed that 1 426 up-regulated and 206 down-regulated differential genes were screened, where 7 immune cell types, including B cell naive, Plasma cells, CD4+T cells, T cells regulatory(Tregs), Macrophages M0, Macrophages M1 and Neutrophils were significantly overexpressed(P<0.05), while others were low expressed(P<0.05). After WGCNA, a total of 820 DEGs were found in the modules most related to immunity. After constructing the PPI network, 10 key genes were screened using plug-ins, and two key genes were further screened using the expression amount of each differential gene in PPI: DLGAP5 and AURKB.CONCLUSION: This study used bioinformatics to screen the infiltration of immune cells and key genes related to immunity in patients with DR. These findings may provide evidences for future research, diagnosis, and treatment of DR.

Identification and verification of α-11 giardin-interacting protein / 中国血吸虫病防治杂志

Objective To identify and verify the interacting protein of α-11 giardin, so as provide the experimental evidence for studies on the α-11 giardin function. Methods The yeast two-hybrid cDNA library of the Giardia lambia C2 strain and the bait plasmid of α-11 giardin were constructed. All proteins interacting with α-11 giardin were screened using the yeast two-hybrid system. α-11 giardin and all screened potential interacting protein genes were constructed into pBiFc-Vc-155 and pBiFc-Vn-173 plasmids, and co-transfected into the breast cancer cell line MDA-MB-231. The interactions between α-11 giardin and interacting proteins were verified using bimolecular fluorescence complementation (BiFC). Results The yeast two-hybrid G. lambia cDNA library which was quantified at 2.715 × 107 colony-forming units (CFU) and the bait plasmid containing α-11 giardin gene without an autoactivation activity were constructed. Following two-round positive screening with the yeast two-hybrid system, two potential proteins interacting with α-11 giardin were screened, including eukaryotic translation initiation factor 5A (EIF5A), calmodulin-dependent protein kinase (CAMKL) and nicotinamide adenine dinucleotide phosphate-specific glutamate dehydrogenase (NADP-GDH), hypothetical protein 1 (GL50803_95880), hypothetical protein 2 (GL50803_87261) and a protein from Giardia canis virus. The α-11 giardin and EIF5A genes were transfected into the pBiFc-Vc-155 and pBiFc-Vn-173 plasmids using BiFC, and the recombinant plasmids pBiFc-Vc-155-α-11 and pBiFc-Vn-173-EIF5A were co-tranfected into MDA-MB-231 cells, which displayed green fluorescence under a microscope, indicating the interaction between α-11 giardin and EIF5A protein in cells. Conclusion The yeast two-hybrid cDNA library of the G. lambia C2 strain has been successfully constructed, and six potential protein interacting with α-11 giardin have been identified, including EIF5A that interacts with α-11 giardin in cells.

Mechanism of Calculus Bovis treating keratitis based on network pharmacology / 中华实验眼科杂志

Objective:To investigate the complex Calculus Bovis-target-keratitis network and to explore the molecular mechanism of Calculus Bovis treating keratitis through network pharmacology. Methods:Genes related to keratitis were searched in the online DisGeNET database and the protein-protein interaction (PPI) network of keratitis-associated proteins was constructed.The components isolated and identified in Calculus Bovis were collected through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP, https: //tcmsp-e.com/tcmsp.php), Chemistry Database by Shanghai Institute of Organic Chemistry of CAS (http: //www.organchem.csdb.cn), and published literature.The canonical SMILES information of the collected components was exported, which were submitted to the SwissTargetPrediction platform to predict potential targets of the components.The active component-predicted target network of Calculus Bovis was constructed and merged with the PPI network of keratitis-associated proteins to build the active component-potential target network of Calculus Bovis and systemically investigate the potential targets and signal pathways of Calculus Bovis in treatment of keratitis.The component-target-pathway network was established to analyze the mechanism of Calculus Bovis treating keratitis. Results:Thirty-nine components isolated and identified in Calculus Bovis were searched and 65 target genes related to keratitis were screened.Of the 28 potential targets involved in Calculus Bovis treating keratitis, there were 7 direct targets, including tumor necrosis factor, caspase 1, Toll-like receptor 9, C-X-C motif chemokine ligand 8, interleukin-6, mitogen-activated protein kinase 8, neurotrophic receptor tyrosine kinase 1.The 28 potential targets were annotated to 12 entries for biological process, 18 for cellular components and 13 for molecular function.In the Kyoto encyclopedia of genes and genomes pathway enrichment analysis, 10 signal pathways were identified as enriched categories, which were mainly related to human cytomegalovirus infection, amoebiasis, antifolate resistance, PI3K-Akt signaling pathway, rheumatoid arthritis, apoptosis, cytokine-cytokine receptor interaction, malaria, non-alcoholic fatty liver disease, interleukin-17 signaling pathway. Conclusions:Calculus Bovis may play an adjuvant therapeutic effect on keratitis through anti-inflammatory, antibacterial, antiviral, immune regulation, inflammatory regulation and other functions.

Identification of anti-Mycobacterium tuberculosis agents targeting the interaction of bacterial division proteins FtsZ and SepFe

Tuberculosis (TB) is one of the deadly diseases caused by Mycobacterium tuberculosis (Mtb), which presents a significant public health challenge. Treatment of TB relies on the combination of several anti-TB drugs to create shorter and safer regimens. Therefore, new anti-TB agents working by different mechanisms are urgently needed. FtsZ, a tubulin-like protein with GTPase activity, forms a dynamic Z-ring in cell division. Most of FtsZ inhibitors are designed to inhibit GTPase activity. In Mtb, the function of Z-ring is modulated by SepF, a FtsZ binding protein. The FtsZ/SepF interaction is essential for FtsZ bundling and localization at the site of division. Here, we established a yeast two-hybrid based screening system to identify inhibitors of FtsZ/SepF interaction in M. tuberculosis. Using this system, we found compound T0349 showing strong anti-Mtb activity but with low toxicity to other bacteria strains and mice. Moreover, we have demonstrated that T0349 binds specifically to SepF to block FtsZ/SepF interaction by GST pull-down, fluorescence polarization (FP), surface plasmon resonance (SPR) and CRISPRi knockdown assays. Furthermore, T0349 can inhibit bacterial cell division by inducing filamentation and abnormal septum. Our data demonstrated that FtsZ/SepF interaction is a promising anti-TB drug target for identifying agents with novel mechanisms.

TRIB3 promotes pulmonary fibrosis through inhibiting SLUG degradation by physically interacting with MDM2

Pulmonary fibrosis (PF) is the pathological structure of incurable fibroproliferative lung diseases that are attributed to the repeated lung injury-caused failure of lung alveolar regeneration (LAR). Here, we report that repetitive lung damage results in a progressive accumulation of the transcriptional repressor SLUG in alveolar epithelial type II cells (AEC2s). The abnormal increased SLUG inhibits AEC2s from self-renewal and differentiation into alveolar epithelial type I cells (AEC1s). We found that the elevated SLUG represses the expression of the phosphate transporter SLC34A2 in AEC2s, which reduces intracellular phosphate and represses the phosphorylation of JNK and P38 MAPK, two critical kinases supporting LAR, leading to LAR failure. TRIB3, a stress sensor, interacts with the E3 ligase MDM2 to suppress SLUG degradation in AEC2s by impeding MDM2-catalyzed SLUG ubiquitination. Targeting SLUG degradation by disturbing the TRIB3/MDM2 interaction using a new synthetic staple peptide restores LAR capacity and exhibits potent therapeutic efficacy against experimental PF. Our study reveals a mechanism of the TRIB3-MDM2-SLUG-SLC34A2 axis causing the LAR failure in PF, which confers a potential strategy for treating patients with fibroproliferative lung diseases.

Bioinformatic analysis identifies potential key genes in the pathogenesis of age-related macular degeneration

Purpose: Age?related macular degeneration (AMD) is the leading cause of irreversible blindness in older individuals. More studies focused on screening the genes, which may be correlated with the development of AMD. With advances in various technologies like multiple microarray datasets, researchers could identify differentially expressed genes (DEGs) more accurately. Exploring abnormal gene expression in disease status can help to understand pathophysiological changes in complex diseases. This study aims to identify the key genes and upstream regulators in AMD and reveal factors, especially genetic association, and the prognosis of the development of this disease. Methods: Data from expression profile GSE125564 and profile GSE29801 were obtained from the Gene Expression Omnibus (GEO) database. We analyzed DEGs using R software (version 3.6.3). Functional enrichment and PPI network analysis were performed using the R package and online database STRING (version 11.0). Results: We compared AMD with normal and found 68 up?regulated genes (URGs) and 25 down?regulated genes (DRGs). We also compared wet AMD with dry AMD and found 41 DRGs in dry AMD. Further work including PPI network analysis, GO classification, and KEGG analysis was done to find connections with AMD. The URGs were mainly enriched in the biological process such as DNA replication, nucleoplasm, extracellular exosome, and cadherin binding. Besides, DRGs were mainly enriched in these functions such as an integral component of membrane and formation of the blood?aqueous barrier (BAB). Conclusion: This study implied that core genes might involve in the process of AMD. Our findings may contribute to revealing the pathogenesis, developing new biomarkers, and raising strategies of treatment for AMD

Structure-function relationships among selected human coronaviruses-Supplementary data

Identifying the key proteins among different types of human disease-causing coronaviruses is essential for the molecular mechanism and thereby designing potential drug molecules. Eight selected proteins of seven types of disease-causing coronaviruses, viz.SARS-CoV-2 (severe acute respiratory syndrome coronavirus2), SARS-CoV (severe acute respiratory syndrome coronavirus), MERS-CoV (middle east respiratory syndrome coronavirus), Human coronavirus OC43, Human coronavirus HKU1, Human coronavirus 229E and Human coronavirus NL63, were chosen for the comparison. Further, an attempt has been made to explore the most important host-pathogen interactions with a special focus on spike (RBD) protein region as this region deemed to be functionally most important. Epitope region was also identified which helps in the design of epitope-based vaccines. The structural comparison carried out among the seven types of human coronaviruses has revealed the molecular level details on the similarity among this series. This study has facilitated the identification of the important residues in the studied proteins which control the key functions such as viral replication and transmission. Thus, exploring the protein space in the family of coronaviruses, provide valuable insights into the molecular basis associated with the role of proteins and viral infections, which is expected to trigger the identification of the drug targets for coronaviruses infections, in a rational way.

Structure-function relationships among selected human coronaviruses-Supplementary data

Identifying the key proteins among different types of human disease-causing coronaviruses is essential for the molecular mechanism and thereby designing potential drug molecules. Eight selected proteins of seven types of disease-causing coronaviruses, viz.SARS-CoV-2 (severe acute respiratory syndrome coronavirus2), SARS-CoV (severe acute respiratory syndrome coronavirus), MERS-CoV (middle east respiratory syndrome coronavirus), Human coronavirus OC43, Human coronavirus HKU1, Human coronavirus 229E and Human coronavirus NL63, were chosen for the comparison. Further, an attempt has been made to explore the most important host-pathogen interactions with a special focus on spike (RBD) protein region as this region deemed to be functionally most important. Epitope region was also identified which helps in the design of epitope-based vaccines. The structural comparison carried out among the seven types of human coronaviruses has revealed the molecular level details on the similarity among this series. This study has facilitated the identification of the important residues in the studied proteins which control the key functions such as viral replication and transmission. Thus, exploring the protein space in the family of coronaviruses, provide valuable insights into the molecular basis associated with the role of proteins and viral infections, which is expected to trigger the identification of the drug targets for coronaviruses infections, in a rational way.

Structure-function relationships among selected human coronaviruses

Identifying the key proteins among different types of human disease-causing coronaviruses is essential for the molecular mechanism and thereby designing potential drug molecules. Eight selected proteins of seven types of disease-causing coronaviruses, viz.SARS-CoV-2 (severe acute respiratory syndrome coronavirus2), SARS-CoV (severe acute respiratory syndrome coronavirus), MERS-CoV (middle east respiratory syndrome coronavirus), Human coronavirus OC43, Human coronavirus HKU1, Human coronavirus 229E and Human coronavirus NL63, were chosen for the comparison. Further, an attempt has been made to explore the most important host-pathogen interactions with a special focus on spike (RBD) protein region as this region deemed to be functionally most important. Epitope region was also identified which helps in the design of epitope-based vaccines. The structural comparison carried out among the seven types of human coronaviruses has revealed the molecular level details on the similarity among this series. This study has facilitated the identification of the important residues in the studied proteins which control the key functions such as viral replication and transmission. Thus, exploring the protein space in the family of coronaviruses, provide valuable insights into the molecular basis associated with the role of proteins and viral infections, which is expected to trigger the identification of the drug targets for coronaviruses infections, in a rational way.

Identification of hub genes in airway epithelial cells of asthma patients by WGCNA and PPI network

Bronchial asthma is a common chronic disease of airway inflammation, high mucus secretion and airway hyper responsiveness. The pathogenetic mechanisms of asthma remain unclear. In this study, we aimed at identifying genes playing an import role in disease-related pathways in airway epithelial cells of asthma patients. Microarray data GSE41861 of asthma airway epithelial cells was used to screen differentially expressed genes (DEGs) through GEO2R analysis. The weighted gene co-expression network analysis (WGCNA) was performed to identify gene co-expression network modules in bronchial asthma. The DAVID database was then used to perform functional and pathway enrichment analysis of these DEGs. In addition, we have conducted protein-protein interaction (PPI) network of DEGs by STRING, and eventually found key genes and significant modules. A total of 315 DEGs (111 up-regulated and 204 down-regulated) were identified between severe asthma and healthy individual, which were mainly involved in pathways of cilium assembly, cilium morphogenesis, axon guidance, positive regulation of fat cell differentiation, and positive regulation of cell substrate adhesion. A total of 60 genes in the black module and green module were considered to be correlated with the severity of asthma. Combining PPI network, several key genes were identified, such as BP2RY14, PTGS1, SLC18A2, SIGLEC6, RGS13, CPA3, and HPGDS. Our findings revealed several genes that may be involved in the process of development of bronchial asthma and potentially be candidate targets for diagnosis or therapy of bronchial asthma.

Research progress of proximity labeling technology based on biotin ligase in proteomics / 中国药科大学学报

@#Proximity-dependent biotinylation (PDB) uses biotin ligase fused to the protein of interest to biotinylate adjacent proteins, purify them with streptavidin beads, and then identify the biotinylated protein by mass spectrometry.This technology can be used to detect transient and/or low affinity interactions, provide a chance to learn more about membrane-less organelles and other subcellular structures that cannot be easily isolated or purified, and fill the gap in traditional methods.This article summarizes the technological development and application of PDB in recent years.

Progress of discovery of molecular glues from natural products and their derivatives / 药学学报

Molecular glues are a class of small molecules that induce the formation of protein-protein interactions to confer new biological function or therapeutic effects. As a unique pharmacological modality, molecular glues could target proteins without druggable binding pockets. It exhibits a variety of functions, including regulating signal transduction, stabilization or degradation of targeted proteins, through sticking different proteins together. This review will summarize the development and current status of molecular glues derived from natural products and analogs by illustrating the discovery and interaction mechanism. We hope to present a systematic view, provide valuable clues for researchers and encourage them to explore more efficient and rational molecular glue discovery strategies.

Inhibition of the CDK9-cyclin T1 protein-protein interaction as a new approach against triple-negative breast cancer

Cyclin-dependent kinase 9 (CDK9) activity is correlated with worse outcomes of triple-negative breast cancer (TNBC) patients. The heterodimer between CDK9 with cyclin T1 is essential for maintaining the active state of the kinase and targeting this protein-protein interaction (PPI) may offer promising avenues for selective CDK9 inhibition. Herein, we designed and generated a library of metal complexes bearing the 7-chloro-2-phenylquinoline CˆN ligand and tested their activity against the CDK9-cyclin T1 PPI. Complex 1 bound to CDK9 via an enthalpically-driven binding mode, leading to disruption of the CDK9-cyclin T1 interaction in vitro and in cellulo. Importantly, complex 1 showed promising anti-metastatic activity against TNBC allografts in mice and was comparably active compared to cisplatin. To our knowledge, 1 is the first CDK9-cyclin T1 PPI inhibitor with anti-metastatic activity against TNBC. Complex 1 could serve as a new platform for the future design of more efficacious kinase inhibitors against cancer, including TNBC.

Advances of inhibitors targeting MLL1-WDR5 protein-protein interaction / 中国药科大学学报

@#Mixed lineage leukemia 1(MLL1) is a member of the "SET" histone methyltransferases family.MLL1 methyltransferase complex, consisting of MLL1, WDR5, RbBP5, Ash2L and DPY-30, regulates methylation level of histone H3 lysine 4 and is essential for the development of human hematopoietic system and self-renewal of blood cells.As an oncogenic protein produced by the translocation of MLL1 gene, the MLL1 fusion protein has been found in some patients with leukemia.Complete MLL1 enzyme complex is required to perform histone demethylation effect, therefore, targeting the protein-protein interaction of MLL1-WDR5 has become a potential strategy for the treatment of leukemia induced by MLL1 fusion protein.This review systematically summarizes the biological mechanism, structural information and inhibitors of MLL1-WDR5 protein-protein interaction, with a perspective based on previously reported data, aiming to provide some reference for further investigation.

Macrophage differential genes and their functions in silicosis based on single cell RNA sequencing and spatial transcriptome sequencing / 环境与职业医学

Background The rise of single cell RNA sequencing (scRNA-seq) and spatial transcriptome sequencing technologies has allowed for intensive study of lung diseases, but both have been poorly studied in silicosis. Objective To explore differentially expressed genes DEGs in silicosis macrophages by scRNA-seq combined with spatial transcriptome sequencing and analyze the potential diagnostic genes. Methods Male C57BL/6 mice (5-6 weeks old, 22-30 g) were randomly divided into 4 groups: normal saline (NS) group for 7 d, NS group for 56 d, SiO2 group for 7 d, and SiO2 group for 56 d, with 1 mouse in each group. A silicosis model was constructed by tracheal drip injection of SiO2 suspension (0.2 g·kg−1, 50 g·cm−2), and the control mice were given the same volume of NS. The right lung was removed for scRNA-seq and the left lung for spatial transcriptome sequencing on day 7 and day 56, respectively. Cell populations were captured using principal component analysis techniques and dimensionality reduction of uniform manifold approximation and projection. The Find Markers function in R language was applied to analyze the DEGs changes of macrophages in two groups of lung tissues, and the corresponding DEGs were subjected to Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes signaling pathway analysis, while STRING and CytoHubba plug-ins of Cytoscape software were applied to protein-protein interaction network analysis to screen out key (Hub) genes. Spatial transcriptome sequencing was used to explore the original location of Hub genes on lung tissue sections and their mapping in lung macrophages. Finally, the correlation of Hub gene expression levels in lung tissues of silicosis patients and mouse silicosis models was verified, the diagnostic efficacy of Hub gene using subject operating characteristic curves (ROC). In vitro experiments by applying cell viability assay were conducted to verify the changes in viability of mouse macrophages (RAW264.7) under SiO2 stimulation. Results The scRNA-seq revealed a total of 20 clusters captured and defined. The results of scRNA-seq and spatial transcriptome sequencing showed an increased number of macrophages in the lung tissue of the SiO2 group compared to the NS group and clustered in the focal areas. Among the 97 macrophage DEGs screened out, 75 were up-regulated genes, and mainly enriched in chemotaxis and migration of neutrophils, chemokine receptor binding, tumor necrosis factor signaling pathway, cytokine-cytokine receptor interaction pathway, and interleukin-17 signaling pathway; and 22 were down-regulated genes, and mainly enriched in late endosomes, peroxisome proliferator-activated receptors signaling pathway, and alcoholic liver disease signaling pathway. A total of 2 core modules and 3 Hub genes were screened out, including Ccl2, Ccl7, and Ptgs2. The scRNA-seq showed that they were expressed at elevated levels in the SiO2 group compared to the NS group and clustered in additional macrophages, and the spatial transcriptome sequencing showed that they clustered in inflammatory areas with nodular lesions. The CCL7 and PTGS2 expressions were increased in the lung tissue of SiO2 patients compared with the healthy subjects, and the areas under the working curve of the subjects were 0.850 and 0.786, respectively. The viability of RAW264.7 cells was enhanced under SiO2 stimulation at 3 h, 6 h, and 12 h compared to those without the stimulation (P<0.05). Conclusion Bioinformatics screening have identified 3 Hub genes (Ccl2, Ccl7, and Ptgs2)and 2 potential diagnostic genes (CCL7 and PTGS2) in the lung tissue of silicosis mice, which may be potential molecular markers of early-stage silicosis with implications for the development and prognosis of silicosis.

Identificación de una triparedoxina peroxidasa citoplasmática en Leishmania braziliensis / Identification of a cytoplasmic tryparedoxin peroxidase from Leishmania braziliensis / Identificação de uma triparedoxina peroxidase citoplasmica de Leishmania braziliensis

Resumen Los sistemas de defensa anti-oxidante utilizados por el parásito intracelular Leishmania braziliensis durante el proceso de infección permiten eliminar especies reactivas de oxígeno y nitrógeno a expensas de equivalentes reductores derivados de la tripanotiona, evitando daños celulares del patógeno. Con el objetivo de identificar potenciales blancos moleculares para el desarrollo de fármacos contra este parásito, se realizó la detección de la enzima triparedoxina peroxidasa citoplasmática de L. braziliensis (LbTXNPxII), la cual es esencial para disminuir concentraciones tóxicas de peróxido de hidrógeno en el contexto de infección. Para esto se generaron anticuerpos policlonales en modelo aviar, partiendo de la clonación, expresión y purificación de la proteína recombinante 6xHis-SUMO-LbTXNPxII (37kDa) en el sistema heterólogo Escherichia coli. La proteína purificada se utilizó como antígeno para la producción de anticuerpos IgY, cuya implementación en estudios in situ permitió detectar y localizar la enzima LbTXNPxII endógena (22kDa) en el citoplasma de promastigotes fijados y verificar su interacción molecular con la nicotinamida/ nicotinato mononucleótido adenilil transferasa, enzima involucrada en la síntesis del NAD. De este modo, se reporta el desarrollo de una herramienta bioquímica para la identificación y estudio de la enzima LbTXNPxII y su participación en vías del metabolismo energético y de defensa anti-oxidante.

Abstract The antioxidant defense systems used by the intracellular parasite Leishmania braziliensis during the infection process make it possible to eliminate reactive oxygen and nitrogen species at the expense of reducing equivalents derived from trypanothione, avoiding cellular damage of the pathogen. In order to identify potential molecular targets for the development of drugs against this parasite, the cytoplasmic tryparedoxin peroxidase of L. braziliensis (LbTXNPxII), which is essential to reduce toxic concentrations of hydrogen peroxide in the context of infection, was carried out. In this regard, polyclonal antibodies were generated in an avian model, starting from the cloning, expression, and purification of the recombinant protein 6xHis-SUMO-LbTXNPxII (37kDa) in the heterologous system of Escherichia coli. The purified protein was used as an antigen for the production of IgY antibodies, whose implementation in in situ experiments allowed the detection and localization of the endogenous LbTXNPxII enzyme (22kDa) in the cytoplasm of fixed promastigotes, as well as the verification of its molecular interaction with nicotinamide/nicotinate mononucleotide adenylyltransferase, an enzyme involved in the synthesis of NAD. Thus, the development of a biochemical tool for the identification and study of the LbTXNPxII enzyme and its participation in energy metabolism and antioxidant defense pathways is reported.

Resumo Os sistemas de defesa antioxidante utilizados pelo parasita intracelular Leishmania braziliensis durante o processo de infecção, permitem a eliminação de espécies reativas de oxigênio e nitrogênio em detrimento de equivalentes redutores derivados de tripanotiona, evitando o dano celular do patógeno. Com o objetivo de identificar potenciais alvos moleculares para o desenvolvimento de drogas contra esse parasita, foi detectada a enzima citoplasmática triparedoxina peroxidase de L. braziliensis (LbTXNPxII), essencial para reduzir as concentrações tóxicas de peróxido de hidrogênio no contexto de infecção. Para isso, anticorpos policlonais foram gerados em modelo aviário, a partir da clonagem, expressão e purificação da proteína recombinante 6xHis-SUMO-LbTXNPxII (37kDa) no sistema heterólogo de Escherichia coli. A proteína purificada foi utilizada como antígeno para a produção de anticorpos IgY, cuja implementação em experimentos in situ permitiu a detecção e localização da enzima LbTXNPxII endógena (22kDa) no citoplasma de promastigotas fixos e verificar sua interação molecular com nicotinamida/nicotinato mononucleotídeo adenililtransferase, enzima envolvida na síntese de NAD. Assim, é relatado o desenvolvimento de uma ferramenta bioquímica para a identificação e estudo da enzima LbTXNPxII e sua participação no metabolismo energético e nas vias de defesa antioxidante.

TRIB3 promotes lung cancer cell survival and inhibits apoptosis through NRF2 activation / 药学学报

The nuclear transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) plays a crucial role in maintaining cellular redox homeostasis. The aberrant NRF2 signaling confers enhanced antioxidant capacity, which is linked to tumor progression and therapeutic resistance. The current study investigates the biological effects and molecular mechanism of tribbles homolog 3 (TRIB3), a stress-induced protein, in regulating cell survival and apoptosis in lung cancer. This study first performed the RNA sequencing data analysis with 576 lung adenocarcinoma patients from the cancer genome atlas (TCGA) database. The NRF2- antioxidant response element (ARE) signature was enriched in patients with high TRIB3 expression. Dual-luciferase reporter assay and real-time quantitative polymerase chain reaction (PCR) were used to confirm the effect of TRIB3 on the kelch-like ECH-associated protein-1 (KEAP1)-NRF2 pathway. Abrogation of TRIB3 impaired NRF2 transcriptional activity and reduced the expression of its target genes. Moreover, TRIB3 enhanced NRF2 stability via blocking KEAP1-NRF2 interaction. TRIB3-depletion promoted reactive oxygen species (ROS) production, restrained cell proliferation, and enhanced carboplatin-induced apoptosis. In addition, NRF2 overexpression recovered the tumor inhibition effect of TRIB3-depletion. Consistently, TRIB3 failed to modulate apoptosis in NRF2 depletion cells. In summary, this study shows that TRIB3 inhibits the KEAP1-NRF2 interaction and upregulates the transcriptional activity of NRF2, thereby promoting lung cancer cell proliferation and reducing the sensitivity to chemotherapy. Targeting the TRIB3-NRF2 signal axis may become a new strategy for ROS homeostasis and lung cancer treatment.

Recent advances in novel anticancer agents targeting β-catenin/TCF4 interaction for molecular cancer therapeutics / 药学学报

Wnt/β-catenin signaling pathway plays an important role in the proliferation, growth, invasion, and metastasis of human cancers. Moreover, β-catenin/T-cell factor 4 (TCF4) interaction regulates the transcription of the key oncogenes in Wnt/β-catenin signaling pathway. Therefore, β-catenin/TCF4 interaction would be a promising therapeutic target for the development of highly selective anticancer agents. At present, most ongoing small-molecule inhibitors targeting β-catenin/TCF4 interaction, including PKF222-815, iCRT3/5/14, LF3, and sanguinarine, have been developed in preclinical studies for human cancer therapeutics. In this review, we summarized the research advances of up-to date inhibitors targeting β-catenin/TCF4 interaction, including the molecular structure and cellular functions of β-catenin in canonical Wnt signaling pathway. This review holds a hopeful avenue for the development of novel and highly selective Wnt inhibitors targeting β-catenin/TCF4 interaction for future anticancer strategy.

Recent advances of MDM2-p53 inhibitors / 药学学报

Protein-protein interactions (PPI) are involved in a variety of biological processes, including cell-to-cell interactions, metabolism and development control. The misregulation, post-translational modification and interference of PPI are related to a variety of human diseases, making the regulation of these interactions a very attractive field of drug discovery. In recent years, the interaction between MDM2 and p53 has become a research hotspot, which plays an important role in the treatment of tumors. But unfortunately there are no such inhibitors approved all over the world. In this view, recent advances of MDM2-p53 inhibitors were briefly described and its inhibitors with potential therapeutic activities in clinical studies were introduced.