Targeting EGFR degradation by autophagosome degraders.

Several generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors have been developed for the treatment of non-small cell lung cancer (NSCLC) in clinic. However, emerging drug resistance mediated by new EGFR mutations or activations by pass, leads to malignant progression of NSCLC. Proteolysis targeting chimeras (PROTACs) have been utilized to overcome the drug resistance acquired by mutant EGFR, newly potent and selective degraders are still need to be developed for clinical applications. Herein, we developed autophagosome-tethering compounds (ATTECs) in which EGFR can be anchored to microtubule-associated protein-1 light chain-3B (LC3B) on the autophagosome with the assistance of the LC3 ligand GW5074. A series of EGFR-ATTECs have been designed and synthesized. Biological evaluations showed that these compounds could degrade EGFR and exhibited moderate inhibitory effects on certain NSCLC cell lines. The ATTEC 12c potently induced the degradation of EGFR with a DC50 value of 0.98 µM and a Dmax value of 81% in HCC827 cells. Mechanistic exploration revealed that the lysosomal pathway was mainly involved in this degradation. Compound 12c also exhibited promising inhibitory activity, as well as degradation efficiency in vivo. Our study highlights that EGFR-ATTECs could be developed as a new expandable EGFR degradation tool and also reveals a novel potential therapeutic strategy to prevent drug resistance acquired EGFR mutations.

Spatio-Temporal Graph Hubness Propagation Model for Dynamic Brain Network Classification.

Dynamic brain network has the advantage over static brain network in characterizing the variation pattern of functional brain connectivity, and it has attracted increasing attention in brain disease diagnosis. However, most of the existing dynamic brain networks analysis methods rely on extracting features from independent brain networks divided by sliding windows, making them hard to reveal the high-order dynamic evolution laws of functional brain networks. Additionally, they cannot effectively extract the spatio-temporal topology features in dynamic brain networks. In this paper, we propose to use optimal transport (OT) theory to capture the topology evolution of the dynamic brain networks, and develop a multi-channel spatio-temporal graph convolutional network that collaboratively extracts the temporal and spatial features from the evolution networks. Specifically, we first adaptively evaluate the graph hubness of brain regions in the brain network of each time window, which comprehensively models information transmission among multiple brain regions. Second, the hubness propagation information across adjacent time windows is captured by optimal transport, describing high-order topology evolution of dynamic brain networks. Moreover, we develop a spatio-temporal graph convolutional network with attention mechanism to collaboratively extract the intrinsic temporal and spatial topology information from the above networks. Finally, the multi-layer perceptron is adopted for classifying the dynamic brain network. The extensive experiment on the collected epilepsy dataset and the public ADNI dataset show that our proposed method not only outperforms several state-of-the-art methods in brain disease diagnosis, but also reveals the key dynamic alterations of brain connectivities between patients and healthy controls.

Catalyst-free late-stage functionalization to assemble α-acyloxyenamide electrophiles for selectively profiling conserved lysine residues.

Covalent probes coupled with chemical proteomics represent a powerful method for investigating small molecule and protein interactions. However, the creation of a reactive warhead within various ligands to form covalent probes has been a major obstacle. Herein, we report a convenient and robust process to assemble a unique electrophile, an α-acyloxyenamide, through a one-step late-stage coupling reaction. This procedure demonstrates remarkable tolerance towards other functional groups and facilitates ligand-directed labeling in proteins of interest. The reactive group has been successfully incorporated into a clinical drug targeting the EGFR L858R mutant, erlotinib, and a pan-kinase inhibitor. The resulting probes have been shown to be able to covalently engage a lysine residue proximal to the ATP-binding pocket of the EGFR L858R mutant. A series of active sites, and Mg2+, ATP-binding sites of kinases, such as K33 of CDK1, CDK2, CDK5 were detected. This is the first report of engaging these conserved catalytic lysine residues in kinases with covalent inhibition. Further application of this methodology to natural products has demonstrated its success in profiling ligandable conserved lysine residues in whole proteome. These findings offer insights for the development of new targeted covalent inhibitors (TCIs).

3D hierarchic interfacial assembly of Au nanocage@Au along with IS-AgMNPs for simultaneous, ultrasensitive, reliable, and quantitative SERS detection of colorectal cancer related miRNAs.

Simultaneous, reliable, and ultra-sensitive analysis of promising miRNA biomarkers of colorectal cancer (CRC) in serum is critical for early diagnosis and prognosis of CRC. In this work, we proposed a novel 3D hierarchic assembly clusters-based SERS strategy with dual enrichment and enhancement designed for the ultrasensitive and quantitative analysis of two upregulated CRC-related miRNAs (miR-21 and miR-31). The biosensor contains the following: (1) SERS probe, Au nanocage@Au nanoparticles (AuNC@Au NPs) labeled with Raman reporters (RaRs). (2) magnetic capture unit, Ag-coated Fe3O4 magnetic nanoparticles (AgMNPs) modified with internal standard (IS). (3) signal amplify probes (SA probes) for the formation of hierarchic assembly clusters. Based on this sensing strategy, the intensity ratio IRaRs/IIS with Lg miRNAs presents a wide linear range (10 aM-100 pM) with a limit of detection of 3.46 aM for miR-21, 6.49 aM for miR-31, respectively. Moreover, the biosensor shows good specificity and anti-interference ability, and the reliability and repeatability of the strategy were then verified by practical detection of clinical serum. Finally, the biosensor can distinguish CRC cancer subjects from normal ones and guide the distinct tumor, lymph node, and metastasis (TNM) stages. Overall, benefiting from the face-to-face coupling of hierarchic assembly clusters, rapid magnetic enrichment and IS signal calibration of AgMNPs, the established biosensor achieves ultra-sensitive and simultaneous detection of dual miRNAs and opens potential avenues for prediction and staging of CRC.

Comprehensive pan-cancer analysis unveils the significant prognostic value and potential role in immune microenvironment modulation of TRIB3.

TRIB3, a pseudokinase, was previously studied within only some specific cancer types, leaving its comprehensive functions in pan-cancer contexts largely unexplored. Here, we performed an integrated analysis of TRIB3 expression, prognosis, genetic alterations, functional enrichment and tumor immune-related characteristics in 33 cancer types. Our results showed that TRIB3 exhibits high expression levels across 24 different cancer types and correlates closely with unfavorable prognoses. Meanwhile, TRIB3 shows mutations in a wide spectrum of 22 distinct cancer types, with the predominant mutation types being missense mutations and gene amplifications, and significant changes in DNA methylation levels in 14 types of cancer. We further discovered that TRIB3 expression is significantly associated with cancer immune-related genome mutations, such as tumor mutational burden (TMB), microsatellite instability (MSI) and DNA mismatch repair (MMR), and infiltration of immunosuppressive cells, such as CD4+ Th2 cells and myeloid-derived suppressor cells (MDSCs), into the tumor microenvironment. These results indicated that the expression of TRIB3 might reshape the tumor immune microenvironment (TIME) and lead to immunosuppressive "cold" tumors. In addition, our results confirmed that the loss of function of TRIB3 inhibits cell proliferation, promotes apoptosis, and leads to significant enrichment of "hot" tumor-related immune pathways, at least in breast cancer cells, which further supports the important role of TRIB3 in cancer prognosis and TIME regulation. Together, this pan-cancer investigation provided a comprehensive understanding of the critical role of TRIB3 in human cancers, and suggested that TRIB3 might be a promising prognostic biomarker and a potential target for cancer immunotherapy.

A large-scale transcriptional analysis reveals herb-derived ginsenoside F2 suppressing hepatocellular carcinoma via inhibiting STAT3.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common type of cancer that shows great morbidity and mortality rates. However, there are limited available drugs to treat HCC. AIM: The present work focused on discovering the potential anti-HCC compounds from traditional Chinese medicine (TCM) by employing high-throughput sequencing-based high-throughput screening (HTS2) together with the liver cancer pathway-associated gene signature. METHODS: HTS2 assay was adopted for identifying herbs. Protein-protein interaction (PPI) network analysis and computer-aided drug design (CADD) were used to identify key targets and screen the candidate natural products of herbs. Molecular docking, network pharmacology analysis, western blotting, immunofluorescent staining, subcellular fractionation experiment, dual-luciferase reporter gene assay, surface plasmon resonance (SPR) as well as nuclear magnetic resonance (NMR) were performed to validate the ability of compound binding with key target and inhibiting its function. Moreover, cell viability, colony-forming, cell cycle assay and animal experiments were performed to examine the inhibitory effect of compound on HCC. RESULTS: We examined the perturbation of 578 herb extracts on the expression of 84 genes from the liver cancer pathway, and identified the top 20 herbs significantly reverting the gene expression of this pathway. Signal transducer and activator of transcription 3  (STAT3)  was identified as one of the key targets of the liver cancer pathway by PPI network analysis. Then, by analyzing compounds from top 20 herbs utilizing CADD, we found ginsenoside F2 (GF2) binds to STAT3 with high affinity, which was further validated by the results from molecular docking, SPR and NMR. Additionally, our results showed that GF2 suppresses the phosphorylation of Y705 of STAT3, inhibits its nuclear translocation, decreases its transcriptional activity and inhibits the growth of HCC in vitro and in vivo. CONCLUSION: Based on this large-scale transcriptional study, a number of anti-HCC herbs were identified. GF2, a compound derived from TCM, was found to be a chemical basis of these herbs in treating HCC. The present work also discovered that GF2 is a new STAT3 inhibitor, which is able to suppress HCC. As such, GF2 represents a new potential anti-HCC therapeutic strategy.

Ethyl acetate extract of Antenoron Filiforme inhibits the proliferation of triple negative breast cancer cells via suppressing Skp2/p21 signaling axis.

BACKGROUND: Triple negative breast cancer (TNBC) has the worst prognosis of the any breast cancer subtype, and the efficient therapeutical treatment is extremely limited. Antenoron filiforme (Thunb.) Roberty & Vautier (AF) is a Traditional Chinese Medicine (TCM), which is well-known for a diverse array of pharmacological activities, including but not limited to anti-inflammatory, antioxidant and anti-tumors properties. Clinically, AF is commonly prescribed for the treatment of gynecological diseases. PURPOSE: Since TNBC is one of the worst gynecological diseases, the objective of this research is to study the anti-TNBC function of the ethyl acetate extract (EAE) of AF (AF-EAE) and disclose its mechanism of action. MATERIALS AND METHODS: With the aim of elucidating the underlying molecular mechanism and possible chemical basis of AF-EAE in the treatment of TNBC, a comprehensive approach combining system pharmacology and transcriptomic analysis, functional experimental validation, and computational modeling was implemented. Firstly, the potential therapeutic targets of AF-EAE treating TNBC were analyzed by systemic pharmacology and transcriptome sequencing. Subsequently, cell viability assays, cell cycle assays, and transplantation tumor assays were employed to detect the inhibitory effect of AF-EAE on TNBC. Apart from that, the western blot and RT-qPCR assays were adopted to verify its mechanism of action. Finally, the potential chemical basis of anti-TNBC function of AF-EAE was screened through molecular docking and validated by molecular dynamics. RESULTS: This study analyzed the differentially expressed genes after AF-EAE treatment by RNA-sequencing (RNA-seq). It was found that most of the genes were abundant in the gene set termed "cell cycle". Besides, AF-EAE could suppress the proliferation of TNBC cells in vitro and in vivo by inhibiting the function of Skp2 protein. AF-EAE could also lead to the accumulation of p21 and a decrease of CDK6/CCND1 protein, thereby stalling the cycle of cell in the G1/S stage. Notably, clinical data survival analysis clearly demonstrated that Skp2 overexpression has been negatively correlated with survival rates in breast cancer (BC) patients. Further, as suggested by molecular docking and molecular dynamics, the quercetin and its analogues of AF-EAE might bind to Skp2 protein. CONCLUSION: In summary, AF-EAE inhibits the growth of TNBC in vitro and in vivo through targeting Skp2/p21 signaling pathway. While providing a novel potential drug for treating TNBC, this study might establish a method to delve into the action mechanism of TCM.

MSTGC: Multi-Channel Spatio-Temporal Graph Convolution Network for Multi-Modal Brain Networks Fusion.

Multi-modal brain networks characterize the complex connectivities among different brain regions from structure and function aspects, which have been widely used in the analysis of brain diseases. Although many multi-modal brain network fusion methods have been proposed, most of them are unable to effectively extract the spatio-temporal topological characteristics of brain network while fusing different modalities. In this paper, we develop an adaptive multi-channel graph convolution network (GCN) fusion framework with graph contrast learning, which not only can effectively mine both the complementary and discriminative features of multi-modal brain networks, but also capture the dynamic characteristics and the topological structure of brain networks. Specifically, we first divide ROI-based series signals into multiple overlapping time windows, and construct the dynamic brain network representation based on these windows. Second, we adopt adaptive multi-channel GCN to extract the spatial features of the multi-modal brain networks with contrastive constraints, including multi-modal fusion InfoMax and inter-channel InfoMin. These two constraints are designed to extract the complementary information among modalities and specific information within a single modality. Moreover, two stacked long short-term memory units are utilized to capture the temporal information transferring across time windows. Finally, the extracted spatio-temporal features are fused, and multilayer perceptron (MLP) is used to realize multi-modal brain network prediction. The experiment on the epilepsy dataset shows that the proposed method outperforms several state-of-the-art methods in the diagnosis of brain diseases.

Midbrain dopamine oxidation links ubiquitination of glutathione peroxidase 4 to ferroptosis of dopaminergic neurons.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual loss of midbrain dopaminergic neurons in association with aggregation of α-synuclein. Oxidative damage has been widely implicated in this disease, though the mechanisms involved remain elusive. Here, we demonstrated that preferential accumulation of peroxidized phospholipids and loss of the antioxidant enzyme glutathione peroxidase 4 (GPX4) were responsible for vulnerability of midbrain dopaminergic neurons and progressive motor dysfunctions in a mouse model of PD. We also established a mechanism wherein iron-induced dopamine oxidation modified GPX4, thereby rendering it amenable to degradation via the ubiquitin-proteasome pathway. In conclusion, this study unraveled what we believe to be a novel pathway for dopaminergic neuron degeneration during PD pathogenesis, driven by dopamine-induced loss of antioxidant GPX4 activity.

Ynamide Coupling Reagent for the Chemical Cross-Linking of Proteins in Live Cells.

Chemical cross-linking of proteins coupled with mass spectrometry analysis (CXMS) is a powerful method for the study of protein structure and protein-protein interactions (PPIs). However, the chemical probes used in the CXMS are limited to bidentate reactive warheads, and the available zero-length cross-linkers are restricted to 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM). To alleviate this issue, an efficient coupling reagent, sulfonyl ynamide, was developed as a new zero-length cross-linker that can connect high-abundance carboxyl residues (D/E) with lysine (K) to form amide bonds in the absence of any catalyst. Significant improvement in the cross-linking efficiency and specificity in comparison with traditional EDC/NHS was achieved with model proteins, which includes inter- and intramolecular conjugations. The cross-linked structures were validated by X-ray crystallography. Importantly, this coupling reagent can be successfully used to capture interacting proteins in the whole proteome and can be a useful reagent for probing potential protein-protein interactions in situ.

Optimization of the Epimedii Folium Mutton-Oil Processing Technology and Testing Its Effect on Zebrafish Embryonic Development.

As a traditional Chinese medicine (TCM), Epimedii folium (EF) has a history in medicine and food that is > 2,000 years old. Clinically, EF processed with mutton oil is often used as a medicine. In recent years, reports of safety risks and adverse reactions of products that use EF as a raw material have gradually increased. Processing can effectively improve the safety of TCM. According to TCM theory, mutton-oil processing can reduce the toxicity of EF and enhance its tonifying effect on the kidneys. However, there is a lack of systematic research and evaluation of EF mutton-oil processing technology. In this study, we used the Box-Behnken experimental design-response surface methodology to optimize the key parameters of the processing technology by assessing the contents of multiple components. The results showed that the optimal mutton-oil processing technology of EF was as follows: heating the mutton oil at 120 °C ± 10 °C, adding the crude EF, stir-frying it gently to 189 °C ± 10 °C until it is evenly shiny, and then removing it and cool. For every 100 kg of EF, 15 kg of mutton oil should be used. The toxicities and teratogenicities of an aqueous extract of crude and mutton-oil processed EF were compared in a zebrafish embryo developmental model. The results showed that the crude herb group was more likely to cause zebrafish deformities, and its half-maximal lethal EF concentration was lower. In conclusion, the optimized mutton-oil processing technology was stable and reliable, with good repeatability. At a certain dose, the aqueous extract of EF was toxic to the development of zebrafish embryos, and the toxicity was stronger for the crude drug than for the processed drug. The results showed that mutton-oil processing reduced the toxicity of crude EF. These findings can be used to improve the quality, uniformity, and clinical safety of mutton oil-processed EF.

Affinity-based protein profiling-driven discovery of myricanol as a Nampt activator.

Herein, we synthesized an affinity-based probe of myricanol (pMY) with a photo-affinity cross-linker to initiate a bioconjugation reaction, which was applied for target identification in live C2C12 myotubes. Pull-down of biotinylated pMY coupled with mass spectroscopy and Western blotting revealed that pMY can bind with nicotinamide phosphoribosyltransferase (Nampt), a rate-limiting enzyme in the nicotinamide adenine dinucleotide salvage pathway. Cellular thermal shift assay, drug affinity responsive target stability assay and recombinant protein labeling further validated the direct interaction between myricanol and Nampt. Myricanol did not affect the protein expression of Nampt, but enhanced its activity. Knock-down of Nampt totally abolished the promoting effect of myricanol on insulin-stimulated glucose uptake in C2C12 myotubes. Taken together, myricanol sensitizes insulin action in myotubes through binding with and activating Nampt.

Yupingfeng San exhibits anticancer effect in hepatocellular carcinoma cells via the MAPK pathway revealed by HTS2 technology.

ETHNOPHARMACOLOGICAL RELEVANCE: Yupingfeng San (YPFS) is a classic rousing prescription in Chinese medicine, with widly clinical application and remarkably curative effect. It consists of three herbs named Astragalus mongholicus Bunge (Huangqi), Atractylodes rubra Dekker (Baizhu) and Saposhnikovia divaricata (Turcz.) Schischk. (Fangfeng), and has a variety of pharmacological activities including immune regulation, antioxidant, anti-tumor, regulation of cytokines, etc. AIM OF THE STUDY: It has been proved that YPFS exerts its anti-tumor effect through enhancing the systemic and local immune responses in tumor patients, moreover, it has the direct tumor-suppressing effect and can reduce the adverse reactions caused by radiotherapy and chemotherapy drugs. Therefore, in this study, we explored the potential anti-HCC mechanism of YPFS based on HTS2 technology and systems pharmacology, aiming to provide a scientific basis for the clinical application of YPFS and a new strategy for Chinese medicine research. MATERIALS AND METHODS: In this study, systems pharmacology plus high throughput sequencing-based high throughput screening (HTS2) technology, and experimental validation were used to investigate the therapeutic mechanisms and the chemical basis of YPFS in HCC treatment. Firstly, the potential therapeutic targets and signaling pathways of YPFS in the treatment of HCC were obtained through systems pharmacology. Subsequently, HTS2 technology combined with PPI network analysis were used to reveal potential therapeutic targets. Finally, the anti-HCC effects and underlying mechanisms of YPFS were further verified in vitro in human hepatocellular carcinoma cell lines. Moreover, the possible chemical basis was explored by drug target verification and molecular docking technology. RESULTS: In total, 183 active ingredients were predicted by YPFS screening and 49 anti-HCC targets were further identified. Most of these targets were enriched into the "MAPK pathway", and the expression of 37 genes was significantly changed after herb treatment. Among them, 5 key targets, including VEGFA, GRB2, JUN, PDGFRB and CDC42, were predicted by protein-protein interaction (PPI) network analysis. According to our results, YPFS inhibited the proliferation, induced the apoptosis and caused cell cycle arrest of HCC cells. In addition, YPFS significantly reduced P38 gene expression. Fangfeng, one of the three herbs in YPFS, significantly down-regulated the expression of more target genes than that of the other two herbs. Lastly, as revealed by molecular docking analysis, 4'-O-glucosyl-5-O-methylvisamminol, an active ingredient identified in Fangfeng, showed a high affinity for P38. CONCLUSION: Taken together, this study shows that YPFS possesses the activities of anti-proliferation and pro-apoptosis in treating HCC, which are achieved by inhibiting the MAPK signaling pathway. P38 is one of the critical targets of YPFS in treating HCC, which may be directly bound and inhibited by 4'-O-glucosyl-5-O-methylvisamminol, a compound derived from YPFS.

Ganglioside lipidomics of CNS myelination using direct infusion shotgun mass spectrometry.

Gangliosides are present and concentrated in axons and implicated in axon-myelin interactions, but how ganglioside composition changes during myelin formation is not known. Here, we present a direct infusion (shotgun) lipidomics method to analyze gangliosides in small amounts of tissue reproducibly and with high sensitivity. We resolve the mouse ganglioside lipidome during development and adulthood and determine the ganglioside content of mice lacking the St3gal5 and B4galnt1 genes that synthesize most ganglioside species. Our results reveal substantial changes in the ganglioside lipidome during the formation of myelinated nerve fibers. In sum, we provide insights into the CNS ganglioside lipidome with a quantitative and sensitive mass spectrometry method. Since this method is compatible with global lipidomic profiling, it will provide insights into ganglioside function in physiology and pathology.

A toxin-deformation dependent inhibition mechanism in the T7SS toxin-antitoxin system of Gram-positive bacteria.

Toxin EsaD secreted by some S. aureus strains through the type VII secretion system (T7SS) specifically kills those strains lacking the antitoxin EsaG. Here we report the structures of EsaG, the nuclease domain of EsaD and their complex, which together reveal an inhibition mechanism that relies on significant conformational change of the toxin. To inhibit EsaD, EsaG breaks the nuclease domain of EsaD protein into two independent fragments that, in turn, sandwich EsaG. The originally well-folded ßßα-metal finger connecting the two fragments is stretched to become a disordered loop, leading to disruption of the catalytic site of EsaD and loss of nuclease activity. This mechanism is distinct from that of the other Type II toxin-antitoxin systems, which utilize an intrinsically disordered region on the antitoxins to cover the active site of the toxins. This study paves the way for developing therapeutic approaches targeting this antagonism.

Taohong Siwu Decoction exerts anticancer effects on breast cancer via regulating MYC, BIRC5, EGF and PIK3R1 revealed by HTS2 technology.

Taohong Siwu Decoction (TSD), a classical gynecological prescription that was firstly reported 600 years ago, has been widely used in the adjuvant treatment of breast cancer (BRCA) in China. However, the mechanism of action of TSD in treating BRCA has remained unclear. Here, high-throughput sequencing-based high-throughput screening (HTS2) technology was used to reveal the molecular mechanism of TSD, combination with bioinformatics and systems pharmacology in this study. Firstly, our results showed that TSD exerts an anticancer effect on BRCA cells by inhibiting cell proliferation, migration and inducing apoptosis as well as cell-cycle arrest. And our results from HTS2 suggested that herbs of TSD could significantly inhibit KRAS pathway and pathway in cancer, and activate apoptosis pathway, p53 pathway and hypoxia pathway, which may lead to the anticancer function of TSD. Further, we found that TSD clearly regulates MYC, BIRC5, EGF, and PIK3R1 genes, which play an important role in the development and progression of tumor and have significant correlation with overall survival in BRCA patients. By molecular docking, we discovered that Pentagalloylglucose, a compound derived from TSD, might directly bind to and inhibit the function of BRD4, which is a reported transcriptional activator of MYC gene, and thus repress the expression of MYC. Taken together, this study explores the mechanism of TSD in anti-BRCA by combining HTS2 technology, bioinformatics analysis and systems pharmacology.

Ynamide Electrophile for the Profiling of Ligandable Carboxyl Residues in Live Cells and the Development of New Covalent Inhibitors.

Covalent inhibitors with an electrophilic warhead have received considerable attention due to their remarkable pharmacological properties. However, the electrophilic warhead in covalent drugs is often an α, ß-unsaturated amide, and the targets are mainly cysteine or lysine residues. Thus, the development of novel electrophiles that can target other amino acids is highly desirable. Ynamide, a useful and versatile building block, is commonly employed in the construction of various compounds in organic synthesis. The performance of this functional group in a proteome-wide environment has been studied here for the first time, and it has been shown that it can efficiently modify carboxyl residues in situ and in vitro. Upon incorporation of this ynamide warhead into the pharmacophores of kinase inhibitors, the resulting compound showed moderate inhibition against the EGFR L858R mutant but not against EGFR WT. This novel electrophilic group can be used in the development of new types of covalent inhibitors.

Roles of lncRNA LVBU in regulating urea cycle/polyamine synthesis axis to promote colorectal carcinoma progression.

Altered expression of Urea Cycle (UC) enzymes occurs in many tumors, resulting a metabolic hallmark termed as UC dysregulation. Polyamines are synthesized from ornithine, and polyamine synthetic genes are elevated in various tumors. However, the underlying deregulations of UC/ polyamine synthesis in cancer remain elusive. Here, we characterized a hypoxia-induced lncRNA LVBU (lncRNA regulation via BCL6/urea cycle) that is highly expressed in colorectal cancer (CRC) and correlates with poor cancer prognosis. Increased LVBU expression promoted CRC cells proliferation, foci formation and tumorigenesis. Further, LVBU regulates urea cycle and polyamine synthesis through BCL6, a negative regulator of p53. Mechanistically, overexpression of LVBU competitively bound miR-10a/miR-34c to protect BCL6 from miR-10a/34c-mediated degradation, which in turn allows BCL6 to block p53-mediated suppression of genes (arginase1 ARG1, ornithine transcarbamylase OTC, ornithine decarboxylase 1 ODC1) involved in UC/polyamine synthesis. Significantly, ODC1 inhibitor attenuated the growth of patient derived xenografts (PDX) that sustain high LVBU levels. Taken together, elevated LVBU can regulate BCL6-p53 signaling axis for systemic UC/polyamine synthesis reprogramming and confers a predilection toward CRC development. Our data demonstrates that further drug development and clinical evaluation of inhibiting UC/polyamine synthesis are warranted for CRC patients with high expression of LVBU.

Analysis of Raw and Processed Cyperi Rhizoma Samples Using Liquid Chromatography-Tandem Mass Spectrometry in Rats with Primary Dysmenorrhea.

Cyperi rhizoma (CR) is widely used in gynecology and is a general medicine for treating women's diseases in China. Since the analgesic effect of CR is enhanced after processing with vinegar, CR processed with vinegar (CRV) is generally used clinically. However, the mechanism by which the analgesic effect is enhanced by vinegar processing is unclear. In this study, the ultra-high pressure liquid chromatographytandem mass spectrometry (UPLC-MS/MS) technique was used to examine changes in the blood levels of the exogenous constituents and metabolites between CR-treated and CRV-treated rats with dysmenorrhea. The results revealed differing levels of 15 constituents and two metabolites in the blood of these rats. Among them, the levels of (-)-myrtenol and [(1R,2S,3R,4R)-3-hydroxy-1,4,7,7-tetramethylbicyclo[2.2.1]hept-2-yl]acetic acid in the CRV group were considerably higher than in the CR group. CRV reduced the level of 2-series prostanoids and 4-series leukotrienes with proinflammatory, platelet aggregation, and vasoconstriction activities and provided analgesic effects by modulating arachidonic acid and linoleic acid metabolism and the biosynthesis of unsaturated fatty acids. This study revealed that vinegar processing enhances the analgesic effect of CR and contributes to our understanding of the mechanism of action of CRV.