The BEL1-like homeodomain protein OsBLH4 regulates rice plant height, grain number, and heading date by repressing the expression of OsGA2ox1.

Gibberellins (GAs) play crucial roles in regulating plant architecture and grain yield of crops. In rice, the inactivation of endogenous bioactive GAs and their precursors by GA 2-oxidases (GA2oxs) regulates stem elongation and reproductive development. However, the regulatory mechanisms of GA2ox gene expression, especially in rice reproductive organs, are unknown. The BEL1-like homeodomain protein OsBLH4, a negative regulatory factor for the rice OsGA2ox1 gene, was identified in this study. Loss of OsBLH4 function results in decreased bioactive GA levels and pleiotropic phenotypes, including reduced plant height, decreased grain number per panicle, and delayed heading date, as also observed in OsGA2ox1-overexpressing plants. Consistent with the mutant phenotype, OsBLH4 was predominantly expressed in shoots and young spikelets; its encoded protein was exclusively localized in the nucleus. Molecular analysis demonstrated that OsBLH4 directly bound to the promoter region of OsGA2ox1 to repress its expression. Genetic assays revealed that OsBLH4 acts upstream of OsGA2ox1 to control rice plant height, grain number, and heading date. Taken together, these results indicate a crucial role for OsBLH4 in regulating rice plant architecture and yield potential via regulation of bioactive GA levels, and provide a potential strategy for genetic improvements of rice.

Transcriptional repressor RST1 controls salt tolerance and grain yield in rice by regulating gene expression of asparagine synthetase.

Salt stress impairs nutrient metabolism in plant cells, leading to growth and yield penalties. However, the mechanism by which plants alter their nutrient metabolism processes in response to salt stress remains elusive. In this study, we identified and characterized the rice (Oryza sativa) rice salt tolerant 1 (rst1) mutant, which displayed improved salt tolerance and grain yield. Map-based cloning revealed that the gene RST1 encoded an auxin response factor (OsARF18). Molecular analyses showed that RST1 directly repressed the expression of the gene encoding asparagine synthetase 1 (OsAS1). Loss of RST1 function increased the expression of OsAS1 and improved nitrogen (N) utilization by promoting asparagine production and avoiding excess ammonium (NH4+) accumulation. RST1 was undergoing directional selection during domestication. The superior haplotype RST1Hap III decreased its transcriptional repression activity and contributed to salt tolerance and grain weight. Together, our findings unravel a synergistic regulator of growth and salt tolerance associated with N metabolism and provide a new strategy for the development of tolerant cultivars.

Near-Infrared Absorbing Para-Azaquinodimethane Conjugated Polymers Synthesized via the Transition-Metal-Free Route toward Efficient Photothermal Conversion.

Conjugated polymers with strong absorption in the second near-infrared (NIR-II) window have multiple applications. However, the development of new type of NIR-II conjugated polymers via facile and green methods remains challenging. Herein, this work reports a mild and convenient transition-metal-free method to synthesize near-infrared absorbing quinoidal conjugated polymers containing para-azaquinodimethane (AQM) moieties. The AQM quinoidal conjugated polymers with unique molecular structures and tunable optoelectronic properties can be synthesized by combining the Knoevenagel polycondensation of aromatic dialdehyde monomers with commercially available 1,4-diacetyl-2,5-piperazinedione and the following alkylation reaction. The resultant polymer PQ-DPP shows remarkable NIR-II absorption with a narrow band gap of about 1.08 eV. PQ-DPP nanoparticles exhibit high photothermal conversion efficiency of up to 48% under 1064 nm laser irradiation (1 W cm-2) endowing this polymer with potential in bio-related applications.

Radiofrequency radiation reshapes tumor immune microenvironment into antitumor phenotype in pulmonary metastatic melanoma by inducing active transformation of tumor-infiltrating CD8+ T and NK cells.

Immunosuppression by the tumor microenvironment is a pivotal factor contributing to tumor progression and immunotherapy resistance. Priming the tumor immune microenvironment (TIME) has emerged as a promising strategy for improving the efficacy of cancer immunotherapy. In this study we investigated the effects of noninvasive radiofrequency radiation (RFR) exposure on tumor progression and TIME phenotype, as well as the antitumor potential of PD-1 blockage in a model of pulmonary metastatic melanoma (PMM). Mouse model of PMM was established by tail vein injection of B16F10 cells. From day 3 after injection, the mice were exposed to RFR at an average specific absorption rate of 9.7 W/kg for 1 h per day for 14 days. After RFR exposure, lung tissues were harvested and RNAs were extracted for transcriptome sequencing; PMM-infiltrating immune cells were isolated for single-cell RNA-seq analysis. We showed that RFR exposure significantly impeded PMM progression accompanied by remodeled TIME of PMM via altering the proportion and transcription profile of tumor-infiltrating immune cells. RFR exposure increased the activation and cytotoxicity signatures of tumor-infiltrating CD8+ T cells, particularly in the early activation subset with upregulated genes associated with T cell cytotoxicity. The PD-1 checkpoint pathway was upregulated by RFR exposure in CD8+ T cells. RFR exposure also augmented NK cell subsets with increased cytotoxic characteristics in PMM. RFR exposure enhanced the effector function of tumor-infiltrating CD8+ T cells and NK cells, evidenced by increased expression of cytotoxic molecules. RFR-induced inhibition of PMM growth was mediated by RFR-activated CD8+ T cells and NK cells. We conclude that noninvasive RFR exposure induces antitumor remodeling of the TIME, leading to inhibition of tumor progression, which provides a promising novel strategy for TIME priming and potential combination with cancer immunotherapy.

Design, synthesis, and biological evaluation of naphthalene imidazo[1,2-b]pyridazine hybrid derivatives as VEGFR selective inhibitors.

The vascular endothelial growth factor receptor (VEGFR) is a receptor tyrosine kinase that is regarded as an emerging target for abnormal angiogenesis diseases. In this study, novel naphthalene imidazo[1,2-b]pyridazine hybrids as VEGFR selective inhibitors were designed and synthesized using a scaffold hopping strategy based on ponatinib, a multitarget kinase inhibitor. Among the evaluated compounds, derivative 9k (WS-011) demonstrated the most potent inhibitory potency against VEGFR-2 (IC50 = 8.4 nM) and displayed superior VEGFR selectivity over a panel of 70 kinases compared with ponatinib. Furthermore, 9k possessed good cytotoxic effects on various cancer cell lines, especially the colon cancer HT-29 cells, with an acceptable oral bioavailability. Moreover, 9k significantly inhibited the migration and invasion of human umbilical vein endothelial cells (HUVEC) cells and induced apoptosis through the upregulation of apoptotic proteins in HT-29 cells. 9k also effectively suppressed the activation of VEGFR-2 signaling pathways, which in turn inhibited the growth of HT-29 cells and the tube formation of HUVECs in vitro. All of the findings revealed that 9k could be considered a promising antiangiogenesis lead that merits further investigation.

The transcription factor OsMYBc and an E3 ligase regulate expression of a K+ transporter during salt stress.

Sodium (Na+) and potassium (K+) homeostasis is essential for plant survival in saline soils. A member of the High-Affinity K+ Transporter (HKT) family in rice (Oryza sativa), OsHKT1;1, is a vital regulator of Na+ exclusion from shoots and is bound by a MYB transcription factor (OsMYBc). Here, we generated transgenic rice lines in the oshkt1;1 mutant background for genetic complementation using genomic OsHKT1;1 containing a native (Com) or mutated (mCom) promoter that cannot be bound by OsMYBc. In contrast to wild-type (WT) or Com lines, the mCom lines were not able to recover the salt-sensitive phenotype of oshkt1;1. The OsMYBc-overexpressing plants were more tolerant to salt stress than WT plants. A yeast two-hybrid screen using the OsMYBc N-terminus as bait identified a rice MYBc stress-related RING finger protein (OsMSRFP). OsMSRFP is an active E3 ligase that ubiquitinated OsMYBc in vitro and mediated 26S proteasome-mediated degradation of OsMYBc under semi-in vitro and in vivo conditions. OsMSRFP attenuated OsMYBc-mediated OsHKT1;1 expression, and knockout of OsMSRFP led to rice salt tolerance. These findings uncover a regulatory mechanism of salt response that fine-tunes OsHKT1;1 transcription by ubiquitination of OsMYBc.

OsCYBDOMG1, a cytochrome b561 domain-containing protein, regulates salt tolerance and grain yield in rice.

KEY MESSAGE: OsCYBDOMG1 positively regulates salt tolerance, plant growth, and grain yield by affecting ascorbate biosynthesis and redox state. Soil salinity is a major abiotic stress affecting rice growth and productivity. Many genes involved in the salt stress response have been identified, but the precise mechanisms underlying salt tolerance remain unclear. In this study, we isolated a salt-sensitive mutant of rice, rss5, which exhibited more severe wilting and chlorosis with a significant increase in lipid peroxidation, electrolyte leakage, and shoot Na+ concentration compared to wild-type plants. Map-based cloning, MutMap analysis, and genetic complementation revealed that a single-nucleotide mutation in a gene encoding a cytochrome b561 domain-containing protein (OsCYBDOMG1) was responsible for the mutant phenotype of rss5. The OsCYBDOMG1 gene was mainly expressed in young shoots and nodes, and the encoded protein was principally located in the plasma membrane and endoplasmic reticulum. Mutations of OsCYBDOMG1 resulted in decreased ascorbic acid (AsA) content and AsA/DHA (dehydroascorbate) ratio, which led to increased H2O2 accumulation and reduced salt tolerance. Moreover, plant growth and grain yield of rss5 and the OsCYBDOMG1 knockout mutant (cr-1) were significantly decreased compared to wild-type plants under normal conditions. The elite haplotype of OsCYBDOMG1 associated with higher salt tolerance and grain width and weight was mainly existed in japonica varieties. These results suggest that OsCYBDOMG1 plays an important role in the regulation of salt tolerance, plant growth, and grain yield in rice.

Overexpression of the sulfate transporter-encoding SULTR2 increases chromium accumulation in Chlamydomonas reinhardtii.

Hexavalent chromium [Cr(Ⅵ)] is a highly toxic contaminant in aquatic systems, and microalgae represent promising bioremediators of metal-containing wastewater. However, the metal-binding capacity of algal cells is limited. Therefore, we improved the cellular Cr(Ⅵ) biosorption capacity of Chlamydomonas reinhardtii by overexpressing the sulfate transporter gene SULTR2. SULTR2 was predominantly located in the cytoplasm of the cell, and few proteins mobilized to the cell membrane as a Cr transporter under Cr stress conditions. Intracellular Cr accumulation was almost doubled in SULTR2-overexpressing transgenic strains after exposure to 30 µM K2 Cr2 O7 for 4 d. Alginate-based immobilization increased the rate of Cr removal from 43.81% to 88.15% for SULTR2-overexpressing transgenic strains after exposure to 10 µM K2 Cr2 O7 for 6 d. The immobilized cells also displayed a significant increase in nutrient removal efficiency compared to that of free-swimming cells. Therefore, SULTR2 overexpression in algae has a great potential for the bioremediation of Cr(Ⅵ)-containing wastewater.

Association between the NEP rs701109 polymorphism and the clinical efficacy and safety of sacubitril/valsartan in Chinese patients with heart failure.

OBJECTIVE: Sacubitril/valsartan is a commonly used medicine for treating heart failure (HF) patients, but the treatment effects significantly vary. Neprilysin (NEP) and carboxylesterase 1 (CES1) play an important role in the efficacy of sacubitril/valsartan. The purpose of this study was to explore the relationship between NEP and CES1 gene polymorphisms and the efficacy and safety of sacubitril/valsartan treatment in HF patients. METHODS: Genotyping of 10 single nucleotide polymorphisms (SNPs) of the NEP and CES1 genes in 116 HF patients was performed by the Sequenom MassARRAY method, and logistic regression and haplotype analysis were used to evaluate the associations between SNPs and the clinical efficacy and safety of sacubitril/valsartan in HF patients. RESULTS: A total of 116 Chinese patients with HF completed the whole trial, and T variations in rs701109 in NEP gene were an independent risk factor (P = 0.013, OR = 3.292, 95% CI:1.287-8.422) for the clinical efficacy of sacubitril/valsartan. Furthermore, haplotype analysis of 6 NEP SNPs (including rs701109) was performed and showed that the CGTACC and TGTACC haplotypes were significantly associated with clinical efficacy (OR = 0.095, 95%CI: 0.012-0.723, P = 0.003; OR = 5.586, 95% CI: 1.621-19.248, P = 0.005). Moreover, no association was found between SNPs of other selected genes in terms of efficacy in HF patients, and no association was observed between SNPs and symptomatic hypotension. CONCLUSION: Our results suggest an association between rs701109 and sacubitril/valsartan response in HF patients. Symptomatic hypotension is not associated with the presence of NEP polymorphisms.

Virtual screening for potential discoidin domain receptor 1 (DDR1) inhibitors based on structural assessment.

Discoidin domain receptor 1 (DDR1) (EC Number 2.7.10.1) has recently been considered as a promising therapeutic target for idiopathic pulmonary fibrosis (IPF). However, none of the currently discovered DDR1 inhibitors have been included in clinical studies due to low target specificity or druggability limitations, necessitating various approaches to develop novel DDR1 inhibitors. In this study, to assure target specificity, a docking assessment of the DDR1 crystal structures was undertaken to find the well-differentiated crystal structure, and 4CKR was identified among many crystal structures. Then, using the best pharmacophore model and molecular docking, virtual screening of the ChEMBL database was done, and five potential molecules were identified as promising inhibitors of DDR1. Subsequently, all hit compound complex systems were validated using molecular dynamics simulations and MM/PBSA methods to assess the stability of the system after ligand binding to DDR1. Based on molecular dynamics simulations and hydrogen-bonding occupancy analysis, the DDR1-Cpd2, DDR1-Cpd17, and DDR1-Cpd18 complex systems exhibited superior stability compared to the DDR1-Cpd1 and DDR-Cpd33 complex systems. Meanwhile, when targeting DDR1, the descending order of the five hit molecules' binding free energies was Cpd17 (- 145.820 kJ/mol) > Cpd2 (- 131.818 kJ/mol) > Cpd18 (- 130.692 kJ/mol) > Cpd33 (- 129.175 kJ/mol) > Cpd1 (- 126.103 kJ/mol). Among them, Cpd2, Cpd17, and Cpd18 showed improved binding characteristics, indicating that they may be potential DDR1 inhibitors. In this research, we developed a high-hit rate, effective screening method that serves as a theoretical guide for finding DDR1 inhibitors for the development of IPF therapeutics.

Pharmacokinetics, safety, and bioequivalence of apixaban tablets in healthy Chinese subjects under fasting and fed conditions.

OBJECTIVE: To evaluate the pharmacokinetics (PK), safety, and bioequivalence of two formulations of apixaban in healthy Chinese subjects under fasting and fed conditions. MATERIALS AND METHODS: A single-center, randomized, open, single-dose, two-period crossover PK study was carried out under fasting and fed conditions in 64 healthy subjects enrolled in either the fasting (36 subjects) or the fed (28 subjects) arms of the study. Subjects received a single oral dose of 2.5 mg apixaban tablets as test (T) or reference (R) formulation. The primary PK parameters determined were the area under the plasma concentration-time curve from zero to t and ∞ (AUC0-t and AUC0-∞) and the maximal plasma concentration (Cmax). Safety was assessed mainly from the occurrence of adverse events (AEs). RESULTS: A single drop-out in the fed arm of the trial was excluded from the statistical evaluation. The 90% confidence intervals (CIs) for the geometric mean ratio (GMR) for T/R using AUC0-t were 95.4 - 100.9% and 97.8 - 103.8%, and for AUC0-∞ were 95.3 - 100.6% and 98.3 - 104.3% under fasting (36 subjects) and fed (27 subjects) conditions, respectively. Similarly, the 90% CIs for Cmax were 94.6 - 103.1% and 88.8 - 102.0% under fasting (36 subjects) and the fed (27 subjects) conditions, respectively. Therefore, the 90% CIs for the T/R AUC and Cmax ratios were within the standard range for bioequivalence (80.0 - 125.0%). There were no serious adverse events (SAEs). CONCLUSION: The test and reference 2.5 mg apixaban tablets were bioequivalent and both showed good tolerability and safety.

Cadmium exposure disturbs myocardial lipid signature and induces inflammation in C57BL/6J mice.

Cadmium is a highly ubiquitous environmental pollutant that poses a serious threat to human health. In this study, we assessed the cardiotoxicity of Cd exposure and explored the possible mechanisms by which Cd exerts its toxic effects. The results demonstrated that exposure to Cd via drinking water containing CdCl2 10 mg/dL for eight consecutive weeks induced cardiac injury in C57BL/6J mice. The histopathological changes of myocardial hemolysis, widening of myocardial space, and fracture of myocardial fiber were observed. Meanwhile, elevated levels of cardiac enzyme markers and up-regulation of pro-apoptotic genes also indicated cardiac injury after Cd exposure. Non-targeted lipidomic analysis demonstrated that Cd exposure altered cardiac lipid metabolism, resulted in an increase in pro-inflammatory lipids, and changed lipid distribution abundance. In addition, Cd exposure affected the secretion of inflammatory cytokines by activating the NF-κB signaling pathway, leading to cardiac inflammation in mice. Taken together, results of our present study expand our understanding of Cd cardiotoxicity at the lipidomic level and provide new experimental evidence for uncovering the association of Cd exposure with cardiovascular diseases.

Manganese overexposure induces Parkinson-like symptoms, altered lipid signature and oxidative stress in C57BL/6 J mouse.

Although adequate intake of manganese (Mn) is essential to humans, Mn in excess is neurotoxic. Exposure to extremely high doses of Mn results in "manganism", a condition that exhibits Parkinson-like symptoms. However, the mechanisms underlying its neurotoxic effects in Mn-induced parkinsonism pathogenesis are unclear. In this study, 8-week-old male C57BL/6 J mice were injected intraperitoneally with saline and 50 mg/kg MnCl2 respectively once daily for 14 days to produce an acute Mn neurotoxicity model. Accumulation of Mn in the midbrain, motor dysfunction and loss of dopaminergic neurons in the substantia nigra evidenced Mn neurotoxicity. Untargeted lipidomic analysis demonstrated that Mn overexposure altered lipidome profiles. A significant modulation of 12 lipid subclasses belonging to 5 different categories were found in the midbrain and among the most abundant lipids were sphingolipids, glycerophospholipids, and glycerides. The levels of sphingomyelin (SM) were significantly decreased after Mn treatment. The expression of SM biosynthesis genes was decreased dramatically while sphingomyelinase was up-regulated. In addition, we observed oxidative stress in both the midbrain of mice and MN9D cells, indicated by the increase of MDA level, the decrease of reduced GSH level and the inhibition of SOD and GPx enzyme activities. There was a correlation between these changes and motor dysfunctions. Overall, our study is the first to use lipidomics techniques to explore the pathogenesis of Mn-induced parkinsonism in C57BL/6 J mice. Mn induced molecular events in the midbrain, such as lipid metabolism disorders, oxidative stress and dopaminergic neurons injury, may mechanistically play important roles in the pathogenesis of Parkinson-like symptoms. Moreover, these findings emphasize the necessity for reducing the health risk of environmental neurotoxic pollutants in relation to parkinsonism.

Chemotaxonomic Variation in Volatile Component Contents in Ancient Platycladus orientalis Leaves with Different Tree Ages in Huangdi Mausoleum.

To gain insight into the differences in the composition and volatile components content in ancient Platycladus orientalis leaves with different tree ages in Huangdi Mausoleum, the volatile components were identified by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) method. The volatile components were statistically analyzed by orthogonal partial least squares discriminant analysis and hierarchical cluster analysis, and the characteristic volatile components were screened. The results exhibited that a total of 72 volatile components were isolated and identified in 19 ancient Platycladus orientalis leaves with different tree ages, and 14 common volatile components were screened. Among them, the contents of α-pinene (6.40-16.76%), sabinene (1.11-7.29%), 3-carene (1.14-15.12%), terpinolene (2.17-4.95%), caryophyllene (8.04-13.53%), α-caryophyllene (7.34-14.41%), germacrene D (5.27-12.13%), (+)-Cedrol (2.34-11.30%) and α-terpinyl acetate (1.29-25.68%) were relatively higher (>1%), accounting for 83.40-87.61% of the total volatile components. Nineteen ancient Platycladus orientalis trees were clustered into three groups through the HCA method based on the 14 common volatile components content. Combined with the results of OPLS-DA analysis, (+)-cedrol, germacrene D, α-caryophyllene, α-terpinyl acetate, caryophyllene, ß-myrcene, ß-elemene and epiglobulol were the differential volatile components to distinguish ancient Platycladus orientalis with different tree ages. The results revealed that the composition of the volatile components in ancient Platycladus orientalis leaves with different tree ages was different, showing different aroma characteristics, which provided a theoretical reference for the differential development and application of volatile components in ancient Platycladus orientalis leaves.

Gastric Bypass Regulates Early Inflammatory Responses in High-Fat Diet-Induced Obese Mice.

INTRODUCTION: Obesity and diabetes are characterized by chronic inflammatory responses. Roux-en-Y gastric bypass (RYGB) is increasingly regarded as an effective approach for the improvement of glucose homeostasis. In this study, we examined the effects of RYGB on the regulation of early inflammatory responses in the liver and adipose tissue in high-fat diet (HFD)-induced obese (DIO) mice. MATERIALS AND METHODS: RYGB was performed in DIO mice followed by analyses of adiposity, insulin sensitivity, plasma and tissue cytokines and adipokines, tissue NF-κB and JNK/c-Jun activation, and tissue macrophage and T-cell subsets. RESULTS: We found that RYGB resulted in sustained improvement of adiposity and insulin sensitivity. Plasma insulin and leptin levels were increased in untreated DIO mice and reduced in RYGB mice. RYGB maintained plasma adiponectin levels and inhibited monocyte chemoattractant protein-1 and interleukin 6 in white adipose tissue (WAT) and liver. RYGB inhibited NF-κB activation in WAT and muscle, but not in the liver. However, RYGB attenuated the JNK/c-Jun signaling pathway in the liver and WAT at 1 wk after surgery, suggesting that RYGB regulates the tissue-specific inflammatory pathway. RYGB reduced M1-like (F4/80+/CD11c+) differentiation and enhanced M2-like population (F4/80+/CD206c+). RYGB also regulated CD4+ and CD8+ T-cell infiltration and increased Treg cells in the liver and WAT at the same time point. CONCLUSIONS: Our findings demonstrate that RYGB improves obesity and insulin resistance, which are associated with the regulation of early inflammatory reactions in the liver and WAT.

Investigation of putative antimicrobial peptides in Carassius gibel, revealing a practical approach to screening antimicrobials.

Antimicrobial peptides (AMPs) and their mimics are rapidly gaining attention as a new class of antimicrobials due to their clinical potential. AMPs are widely distributed throughout nature and participate in the innate host defense. In this study, 18 AMPs, including 3 ß-defensins, 3 hepcidins, 4 liver-expressed antimicrobial peptide 2 (LEAP-2) compounds, 4 g-type lysozymes, 2 c-type lysozymes, and 2 NK-lysins, were identified from the genome of Carassius auratus by a homologous search and were further classified based on their fundamental structural features and molecular phylogeny. C. auratus AMPs were found to be ubiquitously distributed in all tested tissues and showed similar expression profiles, with the exception of ß-defensins, when RT-qPCR was used to investigate the tissue distribution of AMPs in healthy Carassius gibel. In addition, the expression levels of NK-lysin genes in the tested tissues tended to be upregulated upon bacterial and viral infection when representative NK-lysins were chosen to examine their relative expression levels in various tissues. Importantly, the synthetic peptide caNKL2102-119, which targets the functional domain of saposin B in caNK-lysins, could effectively counter Aeromonas hydrophila, Staphylococcus aureus, and Escherichia coli with minimum inhibitory concentration (MIC) values of 3-6 µg/mL, as well as inhibit the proliferation of spring viraemia of carp virus (SVCV). These results provide potential targets for antibiotic-free breeding in the aquaculture industry.

Systematic research on gallium atom-doped neutral small- and medium-sized gas-phase magnesium clusters: A DFT study of GaMgn (n=2-12) clusters.

Structure, stability, charge transfer, chemical bonding, and spectroscopic properties of Ga atom-doped neutral Mgn (n = 2-12) clusters have been systematically investigated by CALYPSO and density functional theory. All cluster structures are based on "tetrahedral" and "yurt-like" growth except for GaMg2. The ground state isomer of GaMg8 with high symmetry structure is predicted to be the best-fit candidate for the "magic" cluster because of its excellent stability. Natural bond orbital calculations reveal that Ga and Mg atoms play the role of electron acceptor and donor in all ground state isomers, while the orbitals in both Ga and Mg are sp-hybridized. Most importantly, chemical bonding studies based on atom-in-molecular theory have shown that the lowest-energy state of GaMg4 is so special, in that it has not only the critical size for the appearance of Mg-Mg covalent bonds, but also the only cluster that has both Ga-Mg covalent and non-covalent bonds. Finally, theoretical calculations of IR and Raman spectra of all ground state isomers indicate that the spectra of these clusters are observable in the low-frequency band, and thus they can be identified by spectroscopic experiments. Furthermore, the bond heterogeneity of the Ga-Mg in the GaMg4 ground state isomer has also been specifically investigated, including the fixed GaMg4 structure with Mg atoms added in different directions, as well as ab initio molecular dynamics sampling at different temperatures.

Design, synthesis and biological evaluation of 2,4-pyrimidinediamine derivatives as ALK and HDACs dual inhibitors for the treatment of ALK addicted cancer.

Simultaneous inhibition of histone deacetylases (HDACs) and anaplastic lymphoma kinase (ALK) could enhance therapeutic activity against ALK addicted cancer cells. Herein, a new series of 2,4-pyrimidinediamine derivatives as ALK and HDACs dual inhibitors were designed, synthesised and evaluated. Compound 12a which possessed good inhibitory potency against ALKwt and HDAC1, exhibited stronger antiproliferative activity than Ceritinib on ALK positive cancer cell lines though inducing cell apoptosis and cell cycle arrest in vitro and in vivo. In addition, the mechanism is further verified by the down-regulation of p-ALK protein, and up-regulation of Acetylated histone 3 (Ac-H3) protein in cancer cells. These results suggested that 12a would be a potential candidate for the ALK addicted cancer treatment.

N6-methyladenosine-mediated downregulation of miR-374c-5p promotes cadmium-induced cell proliferation and metastasis by targeting GRM3 in breast cancer cells.

Cadmium (Cd) is a toxic heavy metal that can facilitate the development and progression of breast cancer (BC). Emerging evidence has indicated that the progression of Cd-exposed BC is related to the dysregulation of microRNAs (miRNAs). The purpose of our study was to investigate the expression pattern and underlying mechanisms of miR-374c-5p in Cd-mediated BC progression. In this study, T-47D cells and MCF-7 cells were treated with different concentrations of Cd (0.1, 1 and 10 µM) for 72 h. MiR-374c-5p expression was downregulated, and transfection of miR-374c-5p mimics significantly decreased BC cell proliferation, migration and invasion induced by 10 µM Cd. Importantly, we used the Cytoscape software plugin cytoHubba to analyse the intersected genes between our RNA-Seq results and the mirDIP database, and six hub genes (CNR1, CXCR4, GRM3, RTN1, SLC1A6 and ZEB1) were identified as potential direct targets of miR-374c-5p in our model; however, luciferase reporter assays indicated that miR-374c-5p only repressed GRM3 by directly binding to its 3'-untranslated region (UTR). Of note, we verified that suppression of N6-methyladenosine (m6A) modification led to miR-374c-5p downregulation by decreasing its RNA transcript stability. Together, these findings demonstrated that m6A modification of pri-miRNA-374c blocks miRNA-374c-5p maturation and then activates GRM3 expression, which drives BC cell metastasis after Cd exposure.

miR-3614-5p downregulation promotes cadmium-induced breast cancer cell proliferation and metastasis by targeting TXNRD1.

Cadmium (Cd), which is considered an endocrine disruptor, has been linked to the onset of breast cancer (BC). Our recent study demonstrated that Cd-induced BC progression has a strong correlation with miR-374c-5p dysregulation. The aim of our work was to investigate other potential miRNAs involved in Cd-induced BC cell proliferation and metastasis. In our study, the miRNA profiles of Cd-treated T-47D cells (10 µM, 72 h) were analyzed by miRNA-seq, and our results confirmed that miR-3614-5p was the top downregulated miRNA. Moreover, miR-3614-5p mimic transfection significantly decreased the proliferative ability, migration and invasive ability of BC cell lines (T-47D and MCF-7). Furthermore, we analyzed the overlapping genes from our RNA-seq data and predicted targets from the mirDIP database, and twelve genes (ALDH1A3, FBN1, GRIA3, NOS1, PLD5, PTGER4, RASGRF2, RELN, RNF150, SLC17A4, TG, and TXNRD1) were identified as potential binding targets of miR-3614-5p in the current model. Nonetheless, only miR-3614-5p inhibition caused an increase in TXNRD1 expression upon Cd exposure in T-47D and MCF-7 cell lines. Importantly, luciferase reporter assays further verified that miR-3614-5p suppressed the expression of TXNRD1 by directly binding to the 3'-untranslated region (UTR), and TXNRD1 inhibition significantly repressed the proliferation and metastasis capacity of BC cells upon Cd exposure. Together, our findings demonstrated that Cd exposure repressed the expression of miR-3614-5p, thus activating TXNRD1 expression, which promoted the abnormal proliferation and metastasis of BC cells.