Multi-omics characterization of esophageal squamous cell carcinoma identifies molecular subtypes and therapeutic targets.

Esophageal squamous cell carcinoma (ESCC) is the predominant form of esophageal cancer and is characterized by an unfavorable prognosis. To elucidate the distinct molecular alterations in ESCC and investigate therapeutic targets, we performed a comprehensive analysis of transcriptomics, proteomics, and phosphoproteomics data derived from 60 paired treatment-naive ESCC and adjacent nontumor tissue samples. Additionally, we conducted a correlation analysis to describe the regulatory relationship between transcriptomic and proteomic processes, revealing alterations in key metabolic pathways. Unsupervised clustering analysis of the proteomics data stratified patients with ESCC into 3 subtypes with different molecular characteristics and clinical outcomes. Notably, subtype III exhibited the worst prognosis and enrichment in proteins associated with malignant processes, including glycolysis and DNA repair pathways. Furthermore, translocase of inner mitochondrial membrane domain containing 1 (TIMMDC1) was validated as a potential prognostic molecule for ESCC. Moreover, integrated kinase-substrate network analysis using the phosphoproteome nominated candidate kinases as potential targets. In vitro and in vivo experiments further confirmed casein kinase II subunit α (CSNK2A1) as a potential kinase target for ESCC. These underlying data represent a valuable resource for researchers that may provide better insights into the biology and treatment of ESCC.

Erianin suppresses constitutive activation of MAPK signaling pathway by inhibition of CRAF and MEK1/2.

Constitutive activation of RAS-RAF-MEK-ERK signaling pathway (MAPK pathway) frequently occurs in many cancers harboring RAS or RAF oncogenic mutations. Because of the paradoxical activation induced by a single use of BRAF or MEK inhibitors, dual-target RAF and MEK treatment is thought to be a promising strategy. In this work, we evaluated erianin is a novel inhibitor of CRAF and MEK1/2 kinases, thus suppressing constitutive activation of the MAPK signaling pathway induced by BRAF V600E or RAS mutations. KinaseProfiler enzyme profiling, surface plasmon resonance (SPR), isothermal titration calorimetry (ITC), cellular thermal shift assay, computational docking, and molecular dynamics simulations were utilized to screen and identify erianin binding to CRAF and MEK1/2. Kinase assay, luminescent ADP detection assay, and enzyme kinetics assay were investigated to identify the efficiency of erianin in CRAF and MEK1/2 kinase activity. Notably, erianin suppressed BRAF V600E or RAS mutant melanoma and colorectal cancer cell by inhibiting MEK1/2 and CRAF but not BRAF kinase activity. Moreover, erianin attenuated melanoma and colorectal cancer in vivo. Overall, we provide a promising leading compound for BRAF V600E or RAS mutant melanoma and colorectal cancer through dual targeting of CRAF and MEK1/2.

Periplogenin suppresses the growth of esophageal squamous cell carcinoma in vitro and in vivo by targeting STAT3.

The mortality rate of esophageal squamous cell carcinoma (ESCC) is higher than that of other cancers worldwide owing to a lack of therapeutic targets and related drugs. This study aimed to find new drugs by targeting an efficacious therapeutic target in ESCC patients. Signal transducer and activator of transcription 3 (STAT3) is hyperactive in ESCC. Herein, we identified a novel STAT3 inhibitor, periplogenin, which strongly inhibited phosphorylation of STAT3 at Tyr705. Docking models and pull-down assays revealed that periplogenin bound directly and specifically to STAT3, leading to significant suppression of subsequent dimerization, nuclear import, and transcription activities. In addition, STAT3 knockdown cell lines were insensitive to periplogenin, whereas in contrast, STAT3-overexpressing cells were more sensitive to periplogenin, indicating that STAT3 was a target of periplogenin. Intraperitoneally administered periplogenin exhibited efficacious therapeutic effects in ESCC patient-derived xenograft models and dramatically impaired the phosphorylation of STAT3 and expression levels of STAT3-mediated downstream genes. Thus, our study demonstrated that periplogenin acted as a new STAT3 inhibitor, suppressing the growth of ESCC in vitro and in vivo, providing a basis for its potential application in ESCC treatment and prevention.

miR-17-3p promotes the proliferation of multiple myeloma cells by downregulating P21 expression through LMLN inhibition.

Multiple myeloma (MM), a hematological malignancy, has a poor prognosis and requires an invasive procedure. Reports have implicated miRNAs in the diagnosis, treatment and prognosis of hematological malignancies. In our study, we evaluated the expression profiles of miR-17-3p in plasma and bone marrow mononuclear cells of monoclonal gammopathy of undetermined significance (MGUS) and MM patients and healthy subjects. The results showed that the plasma and mononuclear cell expression levels of miR-17-3p in MM patients were higher than those in MGUS patients and normal controls. In addition, the expression of miR-17-3p was positively correlated with diagnostic indexes, such as marrow plasma cell abundance and serum M protein level, and positively correlated with the International Staging System stage of the disease. Receiver operating characteristic curve analysis suggested that miR-17-3p might be a diagnostic index of MM. Moreover, miR-17-3p regulated cell proliferation, apoptosis and the cell cycle through P21 in MM cell lines and promoted MM tumor growth in vivo. Furthermore, we predicted and verified LMLN as a functional downstream target gene of miR-17-3p. Negatively regulated by miR-17-3p, LMLN inhibits MM cell growth, exerting a tumor suppressive function through P21. Taken together, our data identify miR-17-3p as a promising diagnostic biomarker for MM in the clinic and unveil a new miR-17-3p-LMLN-P21 axis in MM progression.

Catalytic route electrochemiluminescence microscopy of cell membranes with nitrogen-doped carbon dots as nano-coreactants.

Catalytic route electrochemiluminescence (ECL) microscopy enables imaging upper cell membranes with freely diffusing Ru(bpy)32+ as the emitter and nitrogen-doped carbon dots as the nano-coreactants and labels. This strategy provides a vertical resolution when studying the ECL profiles at different heights and realizes the ECL imaging of the externalized phosphatidylserine.

Mitophagy receptor FUNDC1 is regulated by PGC-1α/NRF1 to fine tune mitochondrial homeostasis.

Mitophagy is an essential cellular autophagic process that selectively removes superfluous and damaged mitochondria, and it is coordinated with mitochondrial biogenesis to fine tune the quantity and quality of mitochondria. Coordination between these two opposing processes to maintain the functional mitochondrial network is of paramount importance for normal cellular and organismal metabolism. However, the underlying mechanism is not completely understood. Here we report that PGC-1α and nuclear respiratory factor 1 (NRF1), master regulators of mitochondrial biogenesis and metabolic adaptation, also transcriptionally upregulate the gene encoding FUNDC1, a previously characterized mitophagy receptor, in response to cold stress in brown fat tissue. NRF1 binds to the classic consensus site in the promoter of Fundc1 to upregulate its expression and to enhance mitophagy through its interaction with LC3. Specific knockout of Fundc1 in BAT results in reduced mitochondrial turnover and accumulation of functionally compromised mitochondria, leading to impaired adaptive thermogenesis. Our results demonstrate that FUNDC1-dependent mitophagy is directly coupled with mitochondrial biogenesis through the PGC-1α/NRF1 pathway, which dictates mitochondrial quantity, quality, and turnover and contributes to adaptive thermogenesis.

Bio-Coreactant-Enhanced Electrochemiluminescence Microscopy of Intracellular Structure and Transport.

A bio-coreactant-enhanced electrochemiluminescence (ECL) microscopy realizes the ECL imaging of intracellular structure and dynamic transport. This microscopy uses Ru(bpy)32+ as the electrochemical molecular antenna connecting extracellular and intracellular environments, and uses intracellular biomolecules as the coreactants of ECL reactions via a "catalytic route". Accordingly, intracellular structures are identified without using multiple labels, and autophagy involving DNA oxidative damage is detected using nuclear ECL signals. A time-resolved image sequence discloses the universal edge effect of cellular electroporation due to the influence of the geometric properties of cell membranes on the induced transmembrane voltage. The dynamic transport of Ru(bpy)33+ in the different cellular compartments unveils the heterogeneous intracellular diffusivity correlating with the actin cytoskeleton. In addition to single-cell studies, the bio-coreactant-enhanced ECL microscopy is used to image a slice of a mouse liver and a colony of Shewanella oneidensis MR-1.

Defective mitochondrial ISCs biogenesis switches on IRP1 to fine tune selective mitophagy.

Both iron metabolism and mitophagy, a selective mitochondrial degradation process via autolysosomal pathway, are fundamental for the cellular well-being. Mitochondria are the major site for iron metabolism, especially the biogenesis of iron-sulfur clusters (ISCs) via the mitochondria-localized ISCs assembly machinery. Here we report that mitochondrial ISCs biogenesis is coupled with receptor-mediated mitophagy in mammalian cells. Perturbation of mitochondrial ISCs biogenesis, either by depleting iron with the iron chelator or by knocking down the core components of the mitochondrial ISCs assembly machinery, triggers FUNDC1-dependent mitophagy. IRP1, one of the cellular iron sensors to maintain iron homeostasis, is crucial for iron stresses induced mitophagy. Knockdown of IRP1 disturbed iron stresses induced mitophagy. Furthermore, IRP1 could bind to a newly characterized IRE in the 5' untranslated region of the Bcl-xL mRNA and suppress its translation. Bcl-xL is an intrinsic inhibitory protein of the mitochondrial phosphatase PGAM5, which catalyzes the dephosphorylation of FUNDC1 for mitophagy activation. Alterations of the IRP1/Bcl-xL axis navigate iron stresses induced mitophagy. We conclude that ISCs serve as physiological signals for mitophagy activation, thus coupling mitophagy with iron metabolism.

Hydrogen Evolution Reaction Monitored by Electrochemiluminescence Blinking at Single-Nanoparticle Level.

Monitoring and characterization methods that provide performance tracking of hydrogen evolution reaction (HER) at the single-nanoparticle level can greatly advance our understanding of catalysts' structure and activity relationships. Electrochemiluminescence (ECL) microscopy is implemented for the first time to identify HER activities of single nanocatalysts and to provide a direction for further optimization. Here, we develop a novel ECL blinking technique at the single-nanoparticle level to directly monitor H2 nanobubbles generated from hollow carbon nitride nanospheres (HCNSs). The ECL ON and OFF mechanisms are identified being closely related to the generation, growth, and collapse of H2 nanobubbles. The power-law distributed durations of ON and OFF states demonstrate multiple catalytic sites with stochastic activities on a single HCNS. The power-law coefficients of ECL blinking increase with improved HER activities from modified HCNSs with other active HER catalysts. Besides, ECL blinking phenomenon provides an explanation for the low cathodic ECL efficiency of semiconductor nanomaterials.

Stable and Monochromatic All-Inorganic Halide Perovskite Assisted by Hollow Carbon Nitride Nanosphere for Ratiometric Electrochemiluminescence Bioanalysis.

Lead halide perovskites have been promising electrochemiluminescence (ECL) candidates because of their excellent photophysical attributes, but their poor stability has severely restricted ECL applications. Herein, the in situ assembly of all-inorganic perovskite CsPbBr3 nanocrystals (CPB) into hollow graphitic carbon nitride nanospheres (HCNS) were described as a novel ECL emitter. The architecture guaranteed not only improved stability because of the peripheral HCNS protecting shell but also high-performance ECL of CPB because of a matching band-edge arrangement. Dual-ECL readouts were obtained from the nanocomposite including an anodic ECL from CPB and a cathodic ECL from HCNS. The former displayed prominent color purity to construct an efficient ECL resonance energy transfer system, and the latter served as an internal standard for a ratiometric analysis. A well-designed DNA probe was further utilized for the targeting of CD44 receptors on the MCF-7 cell surface and the double signal amplification. The sensing strategy exhibited good analytical performance for MCF-7 cells, ranging from 1.0 × 103 to 3.2 × 105 cells mL-1 with a detection limit of 320 cells mL-1. Sensitive and accurate evaluation of CD44 expression was finally achieved at 0.22 pM. This work is the first attempt to use halide perovskite for reliable ECL bioanalysis and provides a perspective to design a perovskite-based nanocomposite as a high-performance ECL emitter for its exclusive ECL system.

Molybdenum Carbide Nanoparticles Coated into the Graphene Wrapping N-Doped Porous Carbon Microspheres for Highly Efficient Electrocatalytic Hydrogen Evolution Both in Acidic and Alkaline Media.

Molybdenum carbide (Mo2C) is recognized as an alternative electrocatalyst to noble metal for the hydrogen evolution reaction (HER). Herein, a facile, low cost, and scalable method is provided for the fabrication of Mo2C-based eletrocatalyst (Mo2C/G-NCS) by a spray-drying, and followed by annealing. As-prepared Mo2C/G-NCS electrocatalyst displays that ultrafine Mo2C nanopartilces are uniformly embedded into graphene wrapping N-doped porous carbon microspheres derived from chitosan. Such designed structure offer several favorable features for hydrogen evolution application: 1) the ultrasmall size of Mo2C affords a large exposed active sites; 2) graphene-wrapping ensures great electrical conductivity; 3) porous structure increases the electrolyte-electrode contact points and lowers the charge transfer resistance; 4) N-dopant interacts with H+ better than C atoms and favorably modifies the electronic structures of adjacent Mo and C atoms. As a result, the Mo2C/G-NCS demonstrates superior HER activity with a very low overpotential of 70 or 66 mV to achieve current density of 10 mA cm-2, small Tafel slope of 39 or 37 mV dec-1, respectively, in acidic and alkaline media, and high stability, indicating that it is a great potential candidate as HER electrocatalyst.

Mitophagy receptors sense stress signals and couple mitochondrial dynamic machinery for mitochondrial quality control.

Mitochondria are essential organelles for many fundamental cellular processes, including energy production, fatty acid ß-oxidation, metabolite synthesis, iron and calcium homeostasis, and programmed cell death. Mitochondrial quality thus influences not only individual cell functions but also whole body metabolism. Dysregulated mitochondrial quality control is closely associated with the progression of aging related diseases, such as cancers and neurodegenerative disorders. Mitochondrial quality is monitored at the protein, organelle and sub-organelle levels. The critical issues are how stresses such as bioenergetic stress, oxidative stress and proteotoxic stress, are sensed and how the mitochondrial events are coordinated. Recently, several receptors were identified to mediate selective mitophagy, which is essential for mitochondrial quality control in yeast and mammalian cells. It is emerging that these receptors sense distinct stress signals and couple mitophagy machineries with mitochondrial fission/fusion machineries for mitochondrial quality control. Herein, we will review recent advances in receptors mediated mitophagy and mitochondrial dynamics for mitochondrial quality control, with attempt to have an integrative view on the molecular mechanisms for mitochondrial quality control.

Selective removal of mitochondria via mitophagy: distinct pathways for different mitochondrial stresses.

The efficient and selective elimination of damaged or excessive mitochondria in response to bioenergetic and environmental cues is critical for maintaining a healthy and appropriate population of mitochondria. Mitophagy is considered to be the central mechanism of mitochondrial quality and quantity control. Atg32, a mitophagy receptor in yeast, recruits mitochondria targeted for degradation into the isolation membrane via both direct and indirect interactions with Atg8. In mammals, different mitophagy effectors, including the mitophagy receptors NIX, BNIP3 and FUDNC1 and the PINK1/Parkin pathway, have been identified to participate in the selective clearance of mitochondria. One common feature of mitophagy receptors is that they harbor an LC3-interacting region (LIR) that interacts with LC3, thus promoting the sequestration of mitochondria into the isolation membrane. Additionally, both receptor- and Parkin/PINK1-mediated mitophagy have been found to be regulated by reversible phosphorylation. Here, we review the recent progress in the understanding of the molecular mechanisms involved in selective mitophagy at multiple levels. We also discuss different mitophagy receptors from an evolutionary perspective and highlight the specific functions of and possible cooperation between distinct mechanisms of mitophagy.

Effect of electro-acupuncture at different acupoints on neuropeptide and somatostatin in rat brain with irritable bowel syndrome.

OBJECTIVE: To compare the regulatory effects of electro-acupuncture (EA) at acupoints Zusanli (ST36) and Hegu (LI4) on the visceral hyper-sensitivity in the rat model of irritable bowel syndrome (IBS), and to explore the acting targets and specialty of acupoints. METHODS: Except 8 rats of the normal control group, the rest 32 rats were prepared to set up the IBS models. IBS animal model was prepared by enema with acetic acid. Model rats were divided into three groups. Except for rats in the model group for control, those in the other two groups were treated 20 min by EA on ST36 (EA-ST36) and LI4 (EA-LI4) respectively for 2 weeks to observe the effect on behavior response of viscera sensitivity. The changes of neuropeptide (NPY), the somatostatin (SS) levels in blood and tissues of brain and intestine were monitored as well. RESULTS: The volume thresholds for abdomen uplifting and back hunching were obviously increased after EA-ST36 (P<0.05), but showed insignificant change after EA-LI4. NPY contents lowered and SS contents increased in model rats; both EA-ST36 and EA-LI4 could raise the level of thalamic NPY (P<0.01 and P<0.05, respectively), but showed insignificant effects on NPY in colonic tissue. As for SS content, its colonic level could be reduced by EA-S36 and EA-LI4 (P<0.01 and P<0.05, respectively), however, its blood level was affected only by EA-ST36 (P<0.05). CONCLUSIONS: EA-ST36 or EA-LI4 could regulate the NPY in thalamus and SS in colonic tissue, the former could affect blood level of SS as well. It is deemed that NPY and SS may be the key substances for regulating the action of acupuncture in the brain-intestinal axis; their different levels could be regarded as an indicator for the functional difference between the acupoints.

Purification and physicochemical properties of different polysaccharide fractions from the water extract of Boschniakia rossica and their effect on macrophages activation.

Today more and more attentions had been attracted by many nutritionists and pharmacologists on polysaccharides from natural plants or animals due to their significant biological activities. In this research three polysaccharides (BRR-W1, BRR-WA1 and BRR-WA2) were isolated and purified from the water extract of Boschniakia rossica by DEAE Sepharose Fast Flow and Sepharose 6 Fast Flow column chromatography. Chemical and physical characteristics of three polysaccharides were investigated by a combination of chemical and instrumental analysis methods. The assays of their effect on macrophages activation were also investigated in vitro, including phagocytosis of macrophages, detections for NO production and TNF-α secretion. The results indicated that the effect of polysaccharides on macrophages activation was influenced by their respective physicochemical properties.

Microwave pretreatment can enhance tolerance of wheat seedlings to CdCl2 stress.

In order to determine the role of microwave in cadmium stress tolerance of wheat (Triticum aestivum L.), seeds were exposed to microwave radiation for 0, 5, 10 and 15 s (wavelength 125 mm, power density 126 mW cm(-2), 2450 MHz), and when the seedlings were 7 d old (with one fully expanded leaves), they were treated with 150 µM CdCl(2) solution for 10 d. Changes in a number of physiological and biochemical characteristics were measured and used as indicators of the protective capacity of microwave radiation in this experiment. Our results showed that 150 µM CdCl(2) treatment reduced plant height, root length, dry weight, AsA and GSH concentration and the activities of SOD, POD, CAT and APX, enhanced the concentration of MDA, H(2)O(2) and the production rate of O(2)- when compared with the control. However, seeds with microwave pretreatment 5 or 10 s conferred tolerance to cadmium stress in wheat seedlings by decreasing the concentration of MDA and H(2)O(2), the production rate of O(2)- and increasing the activities of SOD, POD, CAT, APX and AsA and GSH concentration. Therefore, antioxidative enzymes and antioxidative compounds may participate in tolerance of wheat seedlings to cadmium stress. The results also showed that the microwave radiation had a positive physiological effect on the growth and development of cadmium stressed seedlings. This is the first investigation reporting the use of microwave pretreatment to enhance cadmium stress tolerance of wheat.