Design, Synthesis, Antifungal Activity, and Mechanism of Action of New Piperidine-4-carbohydrazide Derivatives Bearing a Quinazolinyl Moiety.

A series of new piperidine-4-carbohydrazide derivatives bearing a quinazolinyl moiety were prepared and evaluated for their fungicidal activities against agriculturally important fungi. Among these derivatives, the chemical structure of compound A45 was clearly verified by X-ray crystallographic analysis. The antifungal bioassays revealed that many compounds in this series possessed good to excellent inhibition effects toward the tested fungi. For example, compounds A13 and A41 had EC50 values of 0.83 and 0.88 µg/mL against Rhizoctonia solani in vitro, respectively, superior to those of positive controls Chlorothalonil and Boscalid (1.64 and 0.96 µg/mL, respectively). Additionally, the above two compounds also exhibited notable inhibitory activities against Verticillium dahliae (with EC50 values of 1.12 and 3.20 µg/mL, respectively), far better than the positive controls Carbendazim and Chlorothalonil (19.3 and 11.0 µg/mL, respectively). More importantly, compound A13 could potently inhibit the proliferation of R. solani in the potted rice plants, showing good in vivo curative and protective efficiencies of 76.9% and 76.6% at 200 µg/mL, respectively. Furthermore, compound A13 demonstrated an effective inhibition of succinate dehydrogenase (SDH) activity in vitro with an IC50 value of 6.07 µM. Finally, the molecular docking study revealed that this compound could be well embedded into the active pocket of SDH via multiple noncovalent interactions, involving residues like SER39, ARG43, and GLY46.

Evaluation of the novel endophytic fungus Chaetomium ascotrichoides 1-24-2 from Pinus massoniana as a biocontrol agent against pine wilt disease caused by Bursaphelenchus xylophilus.

BACKGROUND: Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD), is an ever-increasing threat to Pinus forests worldwide. This study aimed to develop biological control of PWD by the application of endophytic fungi isolated from healthy pine trees. RESULTS: We successfully isolated a novel endophytic fungal strain 1-24-2 from branches of healthy Pinus massoniana. The culture filtrates (CFs) of strain 1-24-2 exhibited strong nematicidal activity against Bursaphelenchus xylophilus, with a corrected mortality rate of 99.00%. Based on the morphological and molecular characteristics, the isolated strain 1-24-2 was identified as Chaetomium ascotrichoides. In the in-planta assay, pine seedlings (2-years-old) treated with 1-24-2 CFs + pine wood nematode (T2) showed a significant control effect of 80%. A total of 24 toxic compounds were first identified from 1-24-2 CFs through gas chromatography-mass spectrometry (GC-MS) analysis, from which O-methylisourea, 2-chlorobenzothiazole, and 4,5,6-trihydroxy-7-methylphthalide showed robust binding sites at Tyr119 against phosphoethanolamine methyltransferase (PMT) protein of Bursaphelenchus xylophilus by molecular docking approach and could be used as potential compounds for developing effective nematicides. Interestingly, strain 1-24-2 produces toxic volatile organic compounds (VOCs), which disturb the natural development process of B. xylophilus, whose total number decreased by up to 83.32% in the treatment group as compared to control and also reduced Botrytis cinerea growth by up to 71.01%. CONCLUSION: Our results highlight the potential of C. ascotrichoides 1-24-2 as a promising biocontrol agent with solid nematicidal activity against B. xylophilus. This is the first report of C. ascotrichoides isolated from P. massoniana exhibiting strong biocontrol potential against B. xylophilus in the world. © 2024 Society of Chemical Industry.

Synthesis and agricultural antimicrobial evaluation of new quinazoline derivatives containing both a piperazine linker and the N-acetyl moiety.

BACKGROUND: To discover more efficient agricultural antimicrobial agents, a series of new quinazoline derivatives containing both a piperazine linker and the N-acetyl moiety were prepared and assessed for their antibacterial and antifungal activities. RESULTS: All the target compounds were characterized by 1H and 13C NMR as well as high-resolution mass spectrometry (HRMS), and the chemical structure of the most potent compound E19 incorporating a 4-trifluoromethoxy substituent was clearly confirmed via single crystal X-ray diffraction measurements. The bioassay results indicated that some compounds possessed notable inhibitory effects in vitro against the bacterium Xanthomonas oryzae pv. oryzicola (Xoc). For example, compound E19 had an EC50 (effective concentration for 50% activity) value of 7.1 µg/mL towards this pathogen, approximately 15- and 10-fold more effective than the commercial bactericides thiodiazole copper and bismerthiazol (EC50 = 110.2 and 72.4 µg/mL, respectively). Subsequently, the mechanistic studies showed that compound E19 likely exerted its antibacterial efficacies by altering the cell morphology, increasing the permeability of bacterial cytoplasmic membrane, suppressing the production of bacterial extracellular polysaccharides and the extracellular enzyme activities (amylase and cellulase), and blocking the swimming motility of Xoc. Moreover, the proteomic analysis revealed that compound E19 could reduce the bacterial flagellar biosynthesis and decrease the flagellar motility by down-regulating the expression of the related differential proteins. CONCLUSION: Compound E19 exhibited good potential for further development as a bactericide candidate for control of Xoc. © 2024 Society of Chemical Industry.

Modulation of luminescence properties of circularly polarized thermally activated delayed fluorescence molecules with axial chirality by donor engineering.

Multifunctional thermally activated delayed fluorescence (TADF) materials are currently a trending research subject for luminescence layer materials of organic light-emitting diodes (OLEDs). Among these, circularly polarized thermally activated delayed fluorescence (CP-TADF) materials have the advantage of being able to directly achieve highly efficient circularly polarized luminescence (CPL). The simultaneous integration of outstanding luminescence efficiency and excellent luminescence asymmetry factor (glum) is a major constraint for the development of CP-TADF materials. Therefore, on the basis of first-principles calculations in conjunction with the thermal vibration correlation function (TVCF) method, we study CP-TADF molecules with different donors to explore the feasibility of using the donor substitution strategy for optimizing the CPL and TADF properties. The results indicate that molecules with the phenothiazine (PTZ) unit as the donor possess small energy difference, a great spin-orbit coupling constant and a rapid reverse intersystem crossing rate, which endow them with remarkable TADF features. Meanwhile, compared with the reported molecules, the three designed molecules exhibit better CPL properties with higher glum values. Effective molecular design strategies by donor engineering to modulate the CPL and TADF properties are theoretically proposed. Our findings reveal the relationship between molecular structures and luminescence properties of CP-TADF molecules and further provide theoretical design strategies for optimizing the CPL and TADF properties.

Overexpression of genes involved in fatty acid biosynthesis increases lipid content in the NaHCO3-tolerant Chlorella sp. JB6.

IMPORTANCE: Fatty acid (FA) contents can be altered in Chlorella JB6 in the presence of sodium bicarbonate (NaHCO3). Overexpression of the FA de novo synthesis genes inhibited the growth of JB6 cells and decreased their resistance to NaHCO3, but these transgenic JB6 strains could grow in a medium containing as high as 300 mM NaHCO3. In JB6, ectopic expression of the FA de novo synthesis genes increased the synthesis of very long-chain saturated FA (> 20C).

Synthesis, X-ray Crystal Structure, and Antimicrobial Studies of New Quinazolin-4(3H)-one Derivatives Containing the 1,2,4-Triazolo[3,4-b][1,3,4]thiadiazole Moiety and 4-Piperidinyl Linker.

A total of 35 new quinazolinone derivatives bearing the 1,2,4-triazolo[3,4-b][1,3,4]thiadiazole scaffold and the 4-piperidinyl linker were designed, prepared, and assessed for their antibacterial and antifungal activities. Among these derivatives, the chemical structure of compound F5 was clearly verified via single-crystal X-ray diffraction analysis. The experimental results revealed that some of the compounds displayed good even excellent inhibitory effects toward the tested phytopathogenic bacteria. For instance, compound F33 was capable of strongly inhibiting Xanthomonas oryzae pv. oryzae (Xoo) in vitro with an EC50 (half-maximal effective concentration) value of 4.1 µg/mL, about 16-fold more effective than the commercialized bactericide bismerthiazol. Significantly, this compound also effectively suppressed the proliferation of Xoo in the potted rice plants, showing a good in vivo protection efficacy of 47.6% at 200 µg/mL. Subsequently, the antibacterial mechanisms of compound F33 were explored by means of different biophysical and biochemical methods. Last, some of the compounds were found to possess relatively good antifungal activities in vitro, like compound F19 against Phytophthora nicotianae (with an inhibition rate of 67.2% at 50 µg/mL). In a word, the current experimental results imply that the 4-piperidinyl-bridged quinazolinone-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole derivatives possess potential as lead compounds for developing more efficient anti-Xoo bactericides.

Design, synthesis, and antimicrobial evaluation of 2-aminothiazole derivatives bearing the 4-aminoquinazoline moiety against plant pathogenic bacteria and fungi.

BACKGROUND: To find more effective agricultural antibiotics, a class of new 2-aminothiazole derivatives containing the 4-aminoquinazoline moiety were synthesized and evaluated for their antimicrobial properties against phytopathogenic bacteria and fungi of agricultural importance. RESULTS: All the target compounds were fully characterized by 1 H NMR, 13 C NMR, and high-resolution mass spectrometry. The bioassay results showed that compound F29 with a 2-pyridinyl substituent exhibited an outstanding antibacterial effect against Xanthomonas oryzae pv. oryzicola (Xoc) in vitro, having an half-maximal effective concentration (EC50 ) value as low as 2.0 µg/mL (over 30-fold more effective than the commercialized agrobactericide bismerthiazol, with an EC50 value of 64.3 µg/mL). In addition, compound F8 with a 2-fluorophenyl group demonstrated a good inhibitory activity toward the bacterium Xanthomonas axonopodis pv. citri (Xac), around twofold more active than bismerthiazol in terms of their EC50 values (22.8 versus 71.5 µg/mL). Interestingly, this compound also demonstrated a notable fungicidal effect against Phytophthora parasitica var. nicotianae, with an EC50 value largely comparable with that of the commercialized fungicide carbendazim. Finally, mechanistic studies revealed that compound F29 exerted its antibacterial effects by increasing the permeability of bacterial membranes, reducing the release of extracellular polysaccharides, and triggering morphological changes of bacterial cells. CONCLUSION: Compound F29 has promising potential as a lead compound for developing more efficient bactericides to fight against Xoc. © 2023 Society of Chemical Industry.

Corrigendum: The m6A methyltransferase METTL16 inhibits the proliferation of pancreatic adenocarcinoma cancer cells via the p21 signaling pathway.

[This corrects the article DOI: 10.3389/fonc.2023.1138238.].

The m6A methyltransferase METTL16 inhibits the proliferation of pancreatic adenocarcinoma cancer cells via the p21 signaling pathway.

Background: Many studies have reported that N6-methyladenosine (m6A) modification plays a critical role in the epigenetic regulation of organisms and especially in the pathogenesis of malignant diseases. However, m6A research has mainly focused on methyltransferase activity mediated by METTL3, and few studies have focused on METTL16. The aim of this study was to investigate the mechanism of METTL16, which mediates m6A modification, and its role in pancreatic adenocarcinoma (PDAC) cell proliferation. Methods: Clinicopathologic and survival data were retrospectively collected from 175 PDAC patients from multiple clinical centers to detect the expression of METTL16. CCK-8, cell cycle, EdU and xenograft mouse model experiments were used to evaluate the proliferation effect of METTL16. Potential downstream pathways and mechanisms were explored via RNA sequencing, m6A sequencing, and bioinformatic analyses. Regulatory mechanisms were studied through methyltransferase inhibition, RIP, MeRIP‒qPCR assays. Results: We found that METTL16 expression was markedly downregulated in PDAC, and multivariate Cox regression analyses revealed that METTL16 was a protective factor for PDAC patients. We also demonstrated that METTL16 overexpression inhibited PDAC cell proliferation. Furthermore, we identified a METTL16-p21 signaling axis, with downregulation of METTL16 resulting in inhibition of CDKN1A (p21). Additionally, METTL16 silencing and overexpression experiments highlighted m6A modification alterations in PDAC. Conclusions: METTL16 plays a tumor-suppressive role and suppresses PDAC cell proliferation through the p21 pathway by mediating m6A modification. METTL16 may be a novel marker of PDAC carcinogenesis and target for the treatment of PDAC.

Rhynchophylline relieves nonalcoholic fatty liver disease by activating lipase and increasing energy metabolism.

Hepatic fat metabolism may be altered in the context of overnutrition and obesity, often resulting in the accumulation of triglycerides in hepatocytes and leading to nonalcoholic fatty liver disease (NAFLD). Natural plant alkaloids have demonstrated great potential for the prevention and treatment of NAFLD. However, the role of rhynchophylline (RHY) in lipid metabolism is not clear. We explored the role of RHY in lipid metabolism in cells treated with oleic and palmitic acids to mimic high-fat diet (HFD) conditions. RHY attenuated oleic and palmitic acid-induced increases in triglyceride accumulation in HepG2, AML12, and LMH cells. RHY also increased energy metabolism and reduced oxidative stress. We further investigated the effect of RHY on hepatic lipid metabolism in mice fed an HFD including 40 mg/kg RHY. RHY alleviated hepatic steatosis, reduced fat deposition, promoted energy metabolism, and improved glucose metabolism. We investigated the mechanism responsible for this activity by docking with key proteins of lipid metabolism disorders using Discovery Studio software, which showed that RHY interacted well with lipases. Finally, we found that adding RHY promoted lipase activity and lipolysis. In conclusion, RHY ameliorated HFD-induced NAFLD and its complications by increasing lipase activity.

Optimisation Models for Pathway Activity Inference in Cancer.

BACKGROUND: With advances in high-throughput technologies, there has been an enormous increase in data related to profiling the activity of molecules in disease. While such data provide more comprehensive information on cellular actions, their large volume and complexity pose difficulty in accurate classification of disease phenotypes. Therefore, novel modelling methods that can improve accuracy while offering interpretable means of analysis are required. Biological pathways can be used to incorporate a priori knowledge of biological interactions to decrease data dimensionality and increase the biological interpretability of machine learning models. METHODOLOGY: A mathematical optimisation model is proposed for pathway activity inference towards precise disease phenotype prediction and is applied to RNA-Seq datasets. The model is based on mixed-integer linear programming (MILP) mathematical optimisation principles and infers pathway activity as the linear combination of pathway member gene expression, multiplying expression values with model-determined gene weights that are optimised to maximise discrimination of phenotype classes and minimise incorrect sample allocation. RESULTS: The model is evaluated on the transcriptome of breast and colorectal cancer, and exhibits solution results of good optimality as well as good prediction performance on related cancer subtypes. Two baseline pathway activity inference methods and three advanced methods are used for comparison. Sample prediction accuracy, robustness against noise expression data, and survival analysis suggest competitive prediction performance of our model while providing interpretability and insight on key pathways and genes. Overall, our work demonstrates that the flexible nature of mathematical programming lends itself well to developing efficient computational strategies for pathway activity inference and disease subtype prediction.

Perillartine protects against metabolic associated fatty liver in high-fat diet-induced obese mice.

Metabolic associated fatty liver disease is the main cause of chronic liver disease in the world, but there is still no effective treatment. In the search for drugs to treat liver steatosis, we screened 303 natural products using HepG2 cells and discovered that perillartine derived from Perilla frutescens (L.) improved fat deposition as well as glucose homeostasis in hepatocytes. In vitro, perillartine reduced the expression of genes involved in lipid synthesis, lipid transport, and gluconeogenesis in hepatocytes, increased the number of mitochondria, and upregulated the phosphorylation of Akt. In vivo, perillartine reduced body weight gain and the fat rate, improved glucose metabolism and energy balance, and altered the gut microbial composition in mice given a high-fat diet. In addition, RORγ was identified as a possible target of perillartine through pharmacophore screening. Functional studies revealed that the overexpression of RORγ blocked the effects of perillartine, suggesting that it reduced lipid accumulation and regulated glucose metabolism by inhibiting the transcriptional activity of RORγ. Our results provide new information on a natural product inhibitor for RORγ and reveal that perillartine is a new candidate for the treatment of obesity and metabolic associated fatty liver disease.

Hesperidin methyl chalcone ameliorates lipid metabolic disorders by activating lipase activity and increasing energy metabolism.

Obesity has become an increasingly serious health issue with the continuous improvement in living standards. Its prevalence has become an economic burden on health care systems worldwide. Flavonoids have been shown to be beneficial in the prevention and treatment of obesity. Here, we evaluated the therapeutic potential of the flavonoid hesperidin methyl chalcone (HMC) on mice with high-fat diet (HFD)-induced hepatic steatosis in vivo and in vitro. Treatment with HMC reduced oleic and palmitic acid-induced increases in intracellular triglyceride accumulation in HepG2, AML12 and LMH cells. HMC also enhanced energy metabolism and lowered oxidative stress. We used Discovery studio to dock key proteins associated with lipid metabolism disorders to HMC, and found that HMC interacted with lipase. Furthermore, we demonstrated that HMC improved lipase activity and lipolysis. In addition, we found that HMC promoted glucose absorption, alleviated lipid metabolic disorders, improved HFD-induced liver injury, and regulated HFD-induced changes in energy metabolism. In conclusion, our study demonstrated that HMC ameliorated HFD-induced obesity and its complications by promoting lipase activity, and provides a novel approach for the prevention and treatment of obesity and related diseases.

Microstructure Evolution and Mechanical Properties of Ferrite-Austenite Duplex Fe-Mn-Al-(Cu)-C Steel under Different Annealing Temperatures.

The effect of Cu addition and the intercritical annealing (IA) temperature on the microstructural evolution and mechanical properties of Fe-0.4C-7Mn-4Al (wt%) was investigated via scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and nanoindentation tests. The results showed that the volume fraction and the average grain size of austenite, and the fraction of high angle grain boundaries, increased with IA temperature increase in the range of 650 °C to 710 °C. The addition of Cu facilitates the formation of Cu-rich nanoparticles, raises the volume fraction of austenite, and delays the recrystallization of austenite. As IA temperature increased, the yield strength (YS), ultimate tensile strength (UTS), and Lüders bands strain (LBS) decreased in both experimental steels. The Cu addition not only increases the YS of medium Mn steel but also benefits the decrease of LBS. The best comprehensive mechanical properties were obtained at the IA temperature of 690 °C in the studied steel, with Cu addition. According to nanoindentation experiments, the Cu addition raises the hardness of ferrite and austenite from 4.7 GPa to 6.3 GPa and 7.4 GPa to 8.5 GPa, respectively, contributing to the increase of YS of medium-Mn steel.

The mechanism of intramolecular halogen bonding enhanced the quantum efficiency of ultralong organic phosphorescence in the aggregated state.

Ultralong organic phosphorescence (UOP) has broad application prospects in many fields, but realizing its high quantum efficiency is still full of challenges. One of the main reasons is that the internal luminescence mechanism is unclear and theoretical investigations to reveal the inner structure-property relationship are highly desired. Herein, the internal mechanism of halogen bonding enhancing the quantum efficiency of UOP is studied through the combination of quantum mechanics and molecular mechanics methods coupled with the thermal vibration correlation function (TVCF) method. Geometric and electronic data are obtained by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. Transition properties, energy gaps, intermolecular interactions, excited state dynamics as well as Huang-Rhys factors and reorganization energies are analyzed in detail. The results show that the high phosphorescence quantum efficiency benefits from the fast intersystem crossing (ISC) process and the slow non-radiative decay process. The halogen bonding, which cooperates with the effects of aromatic carbonyl and heavy atoms, not only accelerates the ISC rate by increasing the spin-orbit coupling effect, but also restricts the molecular motion and reduces the non-radiative energy consumption. Furthermore, through wise molecular design, an efficient UOP molecule with fast ISC and slow non-radiative decay rates is proposed. This work provides an insight into realizing efficient UOP emission via intramolecular halogen bonding.

Hsa-miR-3178/RhoB/PI3K/Akt, a novel signaling pathway regulates ABC transporters to reverse gemcitabine resistance in pancreatic cancer.

BACKGROUND: Although gemcitabine has been considered as the first-line drug for advanced pancreatic cancer (PC), development of resistance to gemcitabine severely limits the effectiveness of this chemotherapy, and the underlying mechanism of gemcitabine resistance remains unclear. Various factors, such as ATP binding cassette (ABC) transporters, microRNAs and their downstream signaling pathways are included in chemoresistance to gemcitabine. This study investigated the potential mechanisms of microRNAs and ABC transporters related signaling pathways for PC resistance to gemcitabine both in vivo and in vitro. METHODS: Immunohistochemistry and Western blotting were applied to detect the expression of ABC transporters. Molecular docking analysis was performed to explore whether gemcitabine interacted with ABC transporters. Gain-of-function and loss-of-function analyses were performed to investigate the functions of hsa-miR-3178 in vitro and in vivo. Bioinformatics analysis, Western blotting and dual-luciferase reporter assay were used to confirm the downstream regulatory mechanisms of hsa-miR-3178. RESULTS: We found that P-gp, BCRP and MRP1 were highly expressed in gemcitabine-resistant PC tissues and cells. Molecular docking analysis revealed that gemcitabine can bind to the ABC transporters. Hsa-miR-3178 was upregulated in gemcitabine resistance PANC-1 cells as compared to its parental PANC-1 cells. Moreover, we found that hsa-miR-3178 promoted gemcitabine resistance in PC cells. These results were also verified by animal experiments. RhoB was down-regulated in gemcitabine-resistant PC cells and it was a downstream target of hsa-miR-3178. Kaplan-Meier survival curve showed that lower RhoB expression was significantly associated with poor overall survival in PC patients. Rescue assays demonstrated that RhoB could reverse hsa-miR-3178-mediated gemcitabine resistance. Interestingly, hsa-miR-3178 promoted gemcitabine resistance in PC by activating the PI3K/Akt pathway-mediated upregulation of ABC transporters. CONCLUSIONS: Our results indicate that hsa-miR-3178 promotes gemcitabine resistance via RhoB/PI3K/Akt signaling pathway-mediated upregulation of ABC transporters. These findings suggest that hsa-miR-3178 could be a novel therapeutic target for overcoming gemcitabine resistance in PC.

Theoretical perspective of relationship between molecular structure and luminescence properties for circularly polarized thermally activated delayed fluorescence.

Circularly polarized luminescence (CPL) molecules with thermally activated delayed fluorescence (TADF) features show promising applications in high-efficiency circularly polarized organic light emitting diodes (CP-OLEDs). Herein, a pair of chiral molecules (R)-ImNT and (S)-ImNT are studied, two kinds of conformations are found by molecular dynamic conformation search, namely the quasi-axial and the quasi-equatorial conformations. Moreover, molecule with quasi-axial conformation is conducive to achieve outstanding CPL properties due to the large contributions of chiral groups to natural transition orbitals. While the energy gaps for quasi-equatorial conformations are significantly reduced and spin-orbit coupling effects between them are obviously increased. In addition, the quasi-equatorial configuration can facilitate the reverse intersystem crossing process to achieve remarkable TADF feature. Relationships between molecular geometries and CPL as well as TADF properties are revealed. Our research elucidates the relationship between geometric structure and luminescence mechanism, which could provide valuable insights for the design of efficient CPL-TADF emitters.

TMPRSS4 Promotes Cell Proliferation and Inhibits Apoptosis in Pancreatic Ductal Adenocarcinoma by Activating ERK1/2 Signaling Pathway.

Transmembrane protease serine 4 (TMPRSS4) is upregulated in various kinds of human cancers, including pancreatic cancer. However, its biological function in pancreatic ductal adenocarcinoma (PDAC) remains unclear. In the current study, real-time qPCR, immunohistochemical staining, Western blotting, and database (Cancer Genome Atlas and Gene Expression) analysis revealed remarkable overexpression of TMPRSS4 in PDAC tissue as compared to non-tumor tissue. The TMPRSS4 overexpression was associated with poor prognosis of PDAC patients. Moreover, multivariate analysis revealed that TMPRSS4 serves as an independent risk factor in PDAC. We performed gain-and loss-of-function analysis and found that TMPRSS4 promotes cellular proliferation and inhibits apoptosis of PDAC cells both in vitro and in vivo. Furthermore, we showed that TMPRSS4 might promote cell proliferation and inhibit apoptosis through activating ERK1/2 signaling pathway in pancreatic cancer cells. These findings were validated by using ERK1/2 phosphorylation inhibitor SCH772984 both in vitro and in vivo. Taken together, this study suggests that TMPRSS4 is a proto-oncogene, which promotes initiation and progression of PDAC by controlling cell proliferation and apoptosis. Our findings indicate that TMPRSS4 could be a promising prognostic biomarker and a therapeutic target for the treatment of pancreatic cancer.

Sensing mechanism of fluorescent sensor to Cu2+ based on inhibiting ultra-fast intramolecular proton transfer process.

A novel and efficient chemosensor 1 for detecting Cu2+ has recently been developed. However, the photophysical properties of chemosensor 1 and its response mechanism to Cu2+ are still unclear. Herein, the density functional theory and the time-dependent density functional theory approaches are implemented to investigate the excited state behavior of chemosensor 1 and its sensing mechanism for Cu2+ is revealed. Through constructing the potential energy curve with the dihedral angle of hydroxide radical as a variable, the irreversibility of the adjustment of the hydrogen proton direction is determined. This feature provides a favorable geometric configuration condition for the formation of intramolecular hydrogen bond. Moreover, the reduced density gradient analysis and topological analysis are performed to visualize the hydrogen bond strength, it is found that the hydrogen bond is enhanced in first singlet excited state (S1) compared with that in ground state (S0). The chemosensor 1 has only a low potential barrier in the S1 state, indicating that it could undergo an ultra-fast excited state intramolecular proton transfer (ESIPT) process. Furthermore, the reaction sites of chemosensor 1 and Cu2+ is theoretically predicted by the electrostatic potential analysis and the coordination mode of 1 + Cu2+-H+ is confirmed. Thus, we verify that the deprotonation inhibits the ESIPT behavior and leads to fluorescence quenching to achieve the recognition of chemosensor 1 to Cu2+. In addition, the binding energy of Cu2+ with chemosensor 1 is greater than that of Mg2+ and Zn2+, the high selectivity of chemosensor 1 to Cu2+ is illustrated. Our investigation clarifies the sensing mechanism of chemosensor 1 to Cu2+ based on inhibiting ultra-fast ESIPT process, which provides a theoretical basis for the development of new metal ion sensors.

Integration of transcriptome and cistrome analysis identifies RUNX1-target genes involved in pancreatic cancer proliferation.

The extremely high proliferation rate of tumor cells contributes to pancreatic cancer (PC) progression. Runt-related transcription factor 1(RUNX1), a key factor in hematopoiesis that was correlated with tumor progression. However, the role of RUNX1 in PC proliferation was still unclear. We found that RUNX1 was significantly upregulated in PC tissues and its expression was negatively associated with prognosis of PC patients in a multicenter analysis according to immunohistochemical (IHC). RUNX1 downregulation in PC resulted in a significantly reduced cell proliferation rate, which was consistent with in vivo subcutaneous tumor formation assay results. RNA-seq and ChIP-seq results revealed that a portion of target genes, including HAP1, GPRC5B, PTPN21, VHL and EN2, were regulated by RUNX1, a finding successfully validated by ChIP-qPCR, qRT-PCR and Western blot. Subsequently, IHC and proliferation assays showed these target genes to be dysregulated in PC, affecting tumor growth. Our data suggest that RUNX1 plays an oncogenic role in tumor proliferation and is a potential prognostic biomarker and therapeutic target for PC.