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1.
Cell ; 179(3): 644-658.e13, 2019 10 17.
Article in English | MEDLINE | ID: mdl-31607511

ABSTRACT

Rotavirus (RV) encounters intestinal epithelial cells amidst diverse microbiota, opening possibilities of microbes influencing RV infection. Although RV clearance typically requires adaptive immunity, we unintentionally generated RV-resistant immunodeficient mice, which, we hypothesized, reflected select microbes protecting against RV. Accordingly, such RV resistance was transferred by co-housing and fecal transplant. RV-protecting microbiota were interrogated by heat, filtration, and antimicrobial agents, followed by limiting dilution transplant to germ-free mice and microbiome analysis. This approach revealed that segmented filamentous bacteria (SFB) were sufficient to protect mice against RV infection and associated diarrhea. Such protection was independent of previously defined RV-impeding factors, including interferon, IL-17, and IL-22. Colonization of the ileum by SFB induced changes in host gene expression and accelerated epithelial cell turnover. Incubation of RV with SFB-containing feces reduced infectivity in vitro, suggesting direct neutralization of RV. Thus, independent of immune cells, SFB confer protection against certain enteric viral infections and associated diarrheal disease.


Subject(s)
Adaptive Immunity/genetics , Diarrhea/microbiology , Intestinal Mucosa/microbiology , Rotavirus Infections/microbiology , Animals , Anti-Infective Agents/pharmacology , Bacteria/genetics , Bacteria/metabolism , Diarrhea/prevention & control , Diarrhea/virology , Feces/microbiology , Gene Expression Regulation/genetics , Humans , Ileum/microbiology , Ileum/pathology , Ileum/virology , Interferons/genetics , Interleukin-17/genetics , Interleukins/genetics , Intestinal Mucosa/pathology , Intestinal Mucosa/virology , Mice , Microbiota/genetics , Rotavirus/pathogenicity , Rotavirus Infections/prevention & control , Rotavirus Infections/virology , Interleukin-22
2.
Nature ; 627(8003): 328-334, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38480966

ABSTRACT

As airborne methane surveys of oil and gas systems continue to discover large emissions that are missing from official estimates1-4, the true scope of methane emissions from energy production has yet to be quantified. We integrate approximately one million aerial site measurements into regional emissions inventories for six regions in the USA, comprising 52% of onshore oil and 29% of gas production over 15 aerial campaigns. We construct complete emissions distributions for each, employing empirically grounded simulations to estimate small emissions. Total estimated emissions range from 0.75% (95% confidence interval (CI) 0.65%, 0.84%) of covered natural gas production in a high-productivity, gas-rich region to 9.63% (95% CI 9.04%, 10.39%) in a rapidly expanding, oil-focused region. The six-region weighted average is 2.95% (95% CI 2.79%, 3.14%), or roughly three times the national government inventory estimate5. Only 0.05-1.66% of well sites contribute the majority (50-79%) of well site emissions in 11 out of 15 surveys. Ancillary midstream facilities, including pipelines, contribute 18-57% of estimated regional emissions, similarly concentrated in a small number of point sources. Together, the emissions quantified here represent an annual loss of roughly US$1 billion in commercial gas value and a US$9.3 billion annual social cost6. Repeated, comprehensive, regional remote-sensing surveys offer a path to detect these low-frequency, high-consequence emissions for rapid mitigation, incorporation into official emissions inventories and a clear-eyed assessment of the most effective emission-finding technologies for a given region.

3.
Nature ; 604(7904): 65-71, 2022 04.
Article in English | MEDLINE | ID: mdl-35388197

ABSTRACT

With the scaling of lateral dimensions in advanced transistors, an increased gate capacitance is desirable both to retain the control of the gate electrode over the channel and to reduce the operating voltage1. This led to a fundamental change in the gate stack in 2008, the incorporation of high-dielectric-constant HfO2 (ref. 2), which remains the material of choice to date. Here we report HfO2-ZrO2 superlattice heterostructures as a gate stack, stabilized with mixed ferroelectric-antiferroelectric order, directly integrated onto Si transistors, and scaled down to approximately 20 ångströms, the same gate oxide thickness required for high-performance transistors. The overall equivalent oxide thickness in metal-oxide-semiconductor capacitors is equivalent to an effective SiO2 thickness of approximately 6.5 ångströms. Such a low effective oxide thickness and the resulting large capacitance cannot be achieved in conventional HfO2-based high-dielectric-constant gate stacks without scavenging the interfacial SiO2, which has adverse effects on the electron transport and gate leakage current3. Accordingly, our gate stacks, which do not require such scavenging, provide substantially lower leakage current and no mobility degradation. This work demonstrates that ultrathin ferroic HfO2-ZrO2 multilayers, stabilized with competing ferroelectric-antiferroelectric order in the two-nanometre-thickness regime, provide a path towards advanced gate oxide stacks in electronic devices beyond conventional HfO2-based high-dielectric-constant materials.

4.
Plant J ; 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39133822

ABSTRACT

UV-B radiation can induce the accumulation of many secondary metabolites, including flavonoids, in plants to protect them from oxidative damage. BRI1-EMS-SUPPRESSOR1 (BES1) has been shown to mediate the biosynthesis of flavonoids in response to UV-B. However, the detailed mechanism by which it acts still needs to be further elucidated. Here, we revealed that UV-B significantly inhibited the transcription of multiple transcription factor genes in tobacco, including NtMYB27, which was subsequently shown to be a repressor of flavonoids synthesis in tobacco. We further demonstrated that NtBES1 directly binds to the E-box motifs present in the promoter of NtMYB27 to mediate its transcriptional repression upon UV-B exposure. The UV-B-repressed NtMYB27 could bind to the ACCT-containing element (ACE) in the promoters of Nt4CL and NtCHS and served as a modulator that promoted the biosynthesis of lignin and chlorogenic acid (CGA) but inhibited the accumulation of flavonoids in tobacco. The expression of NtMYB27 was also significantly repressed by heat stress, suggesting its putative roles in regulating heat-induced flavonoids accumulation. Taken together, our results revealed the role of NtBES1 and NtMYB27 in regulating the synthesis of flavonoids during the plant response to UV-B radiation in tobacco.

5.
Development ; 149(10)2022 05 15.
Article in English | MEDLINE | ID: mdl-35502748

ABSTRACT

Adventitious roots (ARs) are an important type of plant root and display high phenotypic plasticity in response to different environmental stimuli. It is known that photoreceptors inhibit darkness-induced hypocotyl adventitious root (HAR) formation by directly stabilizing Aux/IAA proteins. In this study, we further report that phytochrome-interacting factors (PIFs) plays a central role in HAR initiation by simultaneously inducing the expression of genes involved in auxin biosynthesis, auxin transport and the transcriptional control of root primordium initiation. We found that, on the basis of their activity downstream of phytochrome, PIFs are required for darkness-induced HAR formation. Specifically, PIFs directly bind to the promoters of some genes involved in root formation, including auxin biosynthesis genes YUCCA2 (YUC2) and YUC6, the auxin influx carrier genes AUX1 and LAX3, and the transcription factors WOX5/7 and LBD16/29, to activate their expression. These findings reveal a previously uncharacterized transcriptional regulatory network underlying HAR formation.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Phytochrome , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant , Hypocotyl/genetics , Hypocotyl/metabolism , Indoleacetic Acids/metabolism , Phytochrome/genetics , Plant Roots/genetics , Plant Roots/metabolism
6.
Drug Resist Updat ; 73: 101060, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38309140

ABSTRACT

Cancer lactate metabolic reprogramming induces an elevated level of extracellular lactate and H+, leading to an acidic immunosuppressive tumor microenvironment (TEM). High lactic acid level may affect the metabolic programs of various cells that comprise an antitumor immune response, therefore, restricting immune-mediated tumor destruction, and leading to therapeutic resistance and unsatisfactory prognosis. Here, we report a metal-phenolic coordination-based nanocomplex loaded with a natural polyphenol galloflavin, which inhibits the function of lactate dehydrogenase, reducing the production of lactic acid, and alleviating the acidic immunosuppressive TME. Besides, the co-entrapped natural polyphenol carnosic acid and the synthetic PEG-Ce6 polyphenol derivative (serving as a photosensitizer) could induce immunogenic cancer cell death upon laser irradiation, which further activates immune system and promotes immune cell recruitment and infiltration in tumor tissues. We demonstrated that this nanocomplex-based combinational therapy could reshape the TME and elicit immune responses in a murine breast cancer model, which provides a promising strategy to enhance the therapeutic efficiency of drug-resistant breast cancer.


Subject(s)
Breast Neoplasms , Neoplasms , Humans , Animals , Mice , Female , Lactic Acid , Polyphenols/pharmacology , Metabolic Reprogramming , Neoplasms/drug therapy , Breast Neoplasms/drug therapy , Phenols , Tumor Microenvironment
7.
Chem Soc Rev ; 53(2): 883-971, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38108127

ABSTRACT

Over the past few decades, there have been major developments in transition metal-catalyzed asymmetric cyclization reactions, enabling the convenient access to a wide spectrum of structurally diverse chiral carbo- and hetero-cycles, common skeletons found in fine chemicals, natural products, pharmaceuticals, agrochemicals, and materials. In particular, a plethora of enantioselective cyclization reactions have been promoted by chiral palladium catalysts owing to their outstanding features. This review aims to collect the latest advancements in enantioselective palladium-catalyzed cyclization reactions over the past eleven years, and it is organized into thirteen sections depending on the different types of transformations involved.

8.
J Am Chem Soc ; 146(31): 21231-21238, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39074300

ABSTRACT

Asymmetric Pd-catalyzed three-component carboamination reactions of dienes to construct chiral cyclohexenylamines, which are of great importance in many fields of chemistry, have remained largely unexplored. Here, we demonstrate a highly enantio- and regioselective Pd/Ming-Phos-catalyzed carboamination reactions of 1,3-cyclohexadiene with readily available aryl iodides and anilines for facile access to diverse valuable chiral cyclohexenylamines. The process shows excellent functional group tolerance, easy scalability, and mild conditions. Moreover, mechanistic studies suggest that this reaction has a first-order dependence on the concentration of the palladium catalyst and aniline.

9.
J Am Chem Soc ; 146(6): 3585-3590, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38316138

ABSTRACT

We report here an expanded porphyrinoid, cyclo[2]pyridine[8]pyrrole, 1, that can exist at three closed-shell oxidation levels. Macrocycle 1 was synthesized via the oxidative coupling of two open chain precursors and fully characterized by means of NMR and UV-vis spectroscopies, MS, and X-ray crystallography. Reduction of the fully oxidized form (1, blue) with NaBH4 produced either the half-oxidized (2, teal) or fully reduced forms (3, pale yellow), depending on the amount of reducing agent used and the presence or absence of air. Reduced products 2 or 3 can be oxidized to 1 by various oxidants (quinones, FeCl3, and AgPF6). Macrocycle 1 also undergoes proton-coupled reductions with I-, Br-, Cl-, SO32-, or S2O32- in the presence of an acid. Certain thiol-containing compounds likewise reduce 1 to 2 or 3. This conversion is accompanied by a readily discernible color change, making cyclo[2]pyridine[8]pyrrole 1 able to differentiate biothiols, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH).

10.
Biochem Biophys Res Commun ; 726: 150235, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-38908345

ABSTRACT

BACKGROUND: Diabetic ulcers (DUs) are characterized by chronic inflammation and delayed re-epithelialization, with a high incidence and weighty economic burden. The primary therapeutic strategies for refractory wounds include surgery, non-invasive wound therapy, and drugs, while the optimum regimen remains controversial. Sirtuin-6 (SIRT6) is a histone deacetylase and a key epigenetic factor that exerts anti-inflammatory and pro-proliferatory effects in wound healing. However, the exact function of SIRT6 in DUs remains unclear. METHODS: We generated tamoxifen-inducible SIRT6 knockout mice by crossing SIRT6flox/flox homozygous mice with UBC-creERT2+ transgenic mice. Systemic SIRT6 null mice, under either normal or diabetic conditions, were utilized to assess the effects of SIRT6 in DUs treatment. Gene and protein expressions of SIRT6 and inflammatory cytokines were measured by Western blotting and RT-qPCR. Histopathological examination confirmed the altered re-epithelialization (PCNA), inflammation (NF-κB p50 and F4/80), and angiogenesis (CD31) markers during DUs restoration. RESULTS: Knockout of SIRT6 inhibited the healing ability of DUs, presenting attenuated re-epithelialization (PCNA), exacerbated inflammation responses (NF-κB p50, F4/80, Il-1ß, Tnf-α, Il-6, Il-10, and Il-4), and hyperplasia vascular (CD31) compared with control mice. CONCLUSIONS: SIRT6 could boost impaired wound healing through improving epidermal proliferation, inflammation, and angiogenesis. Our study highlighted the therapeutic potential of the SIRT6 agonist for DUs treatment.


Subject(s)
Mice, Knockout , Sirtuins , Wound Healing , Animals , Wound Healing/genetics , Sirtuins/genetics , Sirtuins/metabolism , Sirtuins/deficiency , Mice , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Cytokines/metabolism , Mice, Inbred C57BL , Inflammation/genetics , Inflammation/pathology , Inflammation/metabolism , Male
11.
Small ; 20(16): e2307792, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38037483

ABSTRACT

A high-throughput ion beam sputtering system is used to synthesize compositional gradient superlattice-like (SLL) thin film libraries of Ge-Sb-Te alloys over the entire phase diagram. The optical properties and structural evolution of the Ge-Sb-Te combinatorial SLL thin film are investigated. A systematic screening over the annealing temperature, annealing time, and modulation period has elucidated the critical factors that affect the stability of the metastable phase and optical properties. It is found that amorphous stability and optical constant are highly dependent on the modulation period and chemical composition of the thin film. This data-driven approach offers new perspectives for accelerating the development of new materials with excellent optical and amorphous stability and for exploring their mechanisms, by greatly expanding the dataset of Ge-Sb-Te alloys with SLL structures through high-throughput experiments.

12.
PLoS Pathog ; 18(7): e1010723, 2022 07.
Article in English | MEDLINE | ID: mdl-35867722

ABSTRACT

Despite the advent of effective antiretroviral therapy (ART), human immunodeficiency virus (HIV) continues to pose major challenges, with extensive pathogenesis during acute and chronic infection prior to ART initiation and continued persistence in a reservoir of infected CD4 T cells during long-term ART. CD101 has recently been characterized to play an important role in CD4 Treg potency. Using the simian immunodeficiency virus (SIV) model of HIV infection in rhesus macaques, we characterized the role and kinetics of CD101+ CD4 T cells in longitudinal SIV infection. Phenotypic analyses and single-cell RNAseq profiling revealed that CD101 marked CD4 Tregs with high immunosuppressive potential, distinct from CD101- Tregs, and these cells also were ideal target cells for HIV/SIV infection, with higher expression of CCR5 and α4ß7 in the gut mucosa. Notably, during acute SIV infection, CD101+ CD4 T cells were preferentially depleted across all CD4 subsets when compared with their CD101- counterpart, with a pronounced reduction within the Treg compartment, as well as significant depletion in mucosal tissue. Depletion of CD101+ CD4 was associated with increased viral burden in plasma and gut and elevated levels of inflammatory cytokines. While restored during long-term ART, the reconstituted CD101+ CD4 T cells display a phenotypic profile with high expression of inhibitory receptors (including PD-1 and CTLA-4), immunsuppressive cytokine production, and high levels of Ki-67, consistent with potential for homeostatic proliferation. Both the depletion of CD101+ cells and phenotypic profile of these cells found in the SIV model were confirmed in people with HIV on ART. Overall, these data suggest an important role for CD101-expressing CD4 T cells at all stages of HIV/SIV infection and a potential rationale for targeting CD101 to limit HIV pathogenesis and persistence, particularly at mucosal sites.


Subject(s)
HIV Infections , Simian Acquired Immunodeficiency Syndrome , Simian Immunodeficiency Virus , Animals , CD4-Positive T-Lymphocytes , HIV Infections/metabolism , Humans , Macaca mulatta
13.
PLoS Biol ; 19(7): e3001330, 2021 07.
Article in English | MEDLINE | ID: mdl-34314414

ABSTRACT

Insect cuticular hydrocarbons (CHCs) serve as important intersexual signaling chemicals and generally show variation between the sexes, but little is known about the generation of sexually dimorphic hydrocarbons (SDHCs) in insects. In this study, we report the molecular mechanism and biological significance that underlie the generation of SDHC in the German cockroach Blattella germanica. Sexually mature females possess more C29 CHCs, especially the contact sex pheromone precursor 3,11-DimeC29. RNA interference (RNAi) screen against the fatty acid elongase family members combined with heterologous expression of the genes in yeast revealed that both BgElo12 and BgElo24 were involved in hydrocarbon (HC) production, but BgElo24 is of wide catalytic activities and is able to provide substrates for BgElo12, and only the female-enriched BgElo12 is responsible for sustaining female-specific HC profile. Repressing BgElo12 masculinized the female CHC profile, decreased contact sex pheromone level, and consequently reduced the sexual attractiveness of female cockroaches. Moreover, the asymmetric expression of BgElo12 between the sexes is modulated by sex differentiation cascade. Specifically, male-specific BgDsx represses the transcription of BgElo12 in males, while BgTra is able to remove this effect in females. Our study reveals a novel molecular mechanism responsible for the formation of SDHCs and also provide evidences on shaping of the SDHCs by sexual selection, as females use them to generate high levels of contact sex pheromone.


Subject(s)
Blattellidae/metabolism , Fatty Acids/metabolism , Hydrocarbons/metabolism , Sex Attractants/metabolism , Sex Characteristics , Sexual Behavior, Animal , Animals , Blattellidae/genetics , Blattellidae/physiology , Female , Genes, Insect , Sex Differentiation/genetics
14.
Environ Sci Technol ; 58(22): 9591-9600, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38759639

ABSTRACT

Methane is a major contributor to anthropogenic greenhouse gas emissions. Identifying large sources of methane, particularly from the oil and gas sectors, will be essential for mitigating climate change. Aircraft-based methane sensing platforms can rapidly detect and quantify methane point-source emissions across large geographic regions, and play an increasingly important role in industrial methane management and greenhouse gas inventory. We independently evaluate the performance of five major methane-sensing aircraft platforms: Carbon Mapper, GHGSat-AV, Insight M, MethaneAIR, and Scientific Aviation. Over a 6 week period, we released metered gas for over 700 single-blind measurements across all five platforms to evaluate their ability to detect and quantify emissions that range from 1 to over 1,500 kg(CH4)/h. Aircraft consistently quantified releases above 10 kg(CH4)/h, and GHGSat-AV and Insight M detected emissions below 5 kg(CH4)/h. Fully blinded quantification estimates for platforms using downward-facing imaging spectrometers have parity slopes ranging from 0.76 to 1.13, with R2 values of 0.61 to 0.93; the platform using continuous air sampling has a parity slope of 0.5 (R2 = 0.93). Results demonstrate that aircraft-based methane sensing has matured since previous studies and is ready for an increasingly important role in environmental policy and regulation.


Subject(s)
Aircraft , Greenhouse Gases , Methane , Methane/analysis , Greenhouse Gases/analysis , Environmental Monitoring/methods , Climate Change , Air Pollutants/analysis
15.
Environ Sci Technol ; 58(31): 13986-13994, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-38992920

ABSTRACT

Previous studies have highlighted the toxicity of pharmaceuticals and personal care products (PPCPs) in plants, yet understanding their spatial distribution within plant tissues and specific toxic effects remains limited. This study investigates the spatial-specific toxic effects of carbamazepine (CBZ), a prevalent PPCP, in plants. Utilizing desorption electrospray ionization mass spectrometry imaging (DESI-MSI), CBZ and its transformation products were observed predominantly at the leaf edges, with 2.3-fold higher concentrations than inner regions, which was confirmed by LC-MS. Transcriptomic and metabolic analyses revealed significant differences in gene expression and metabolite levels between the inner and outer leaf regions, emphasizing the spatial location's role in CBZ response. Notably, photosynthesis-related genes were markedly downregulated, and photosynthetic efficiency was reduced at leaf edges. Additionally, elevated oxidative stress at leaf edges was indicated by higher antioxidant enzyme activity, cell membrane impairment, and increased free fatty acids. Given the increased oxidative stress at the leaf margins, the study suggests using in situ Raman spectroscopy for early detection of CBZ-induced damage by monitoring reactive oxygen species levels. These findings provide crucial insights into the spatial toxicological mechanisms of CBZ in plants, forming a basis for future spatial toxicology research of PPCPs.


Subject(s)
Carbamazepine , Carbamazepine/toxicity , Plant Leaves/drug effects , Oxidative Stress , Multiomics
16.
J Chem Phys ; 160(8)2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38385512

ABSTRACT

We present a numerically exact approach for evaluating vibrationally resolved electronic spectra at finite temperatures using the coherence thermofield dynamics. In this method, which avoids implementing an algorithm for solving the von Neumann equation for coherence, the thermal vibrational ensemble is first mapped to a pure-state wavepacket in an augmented space, and this wavepacket is then propagated by solving the standard, zero-temperature Schrödinger equation with the split-operator Fourier method. We show that the finite-temperature spectra obtained with the coherence thermofield dynamics in a Morse potential agree exactly with those computed by Boltzmann-averaging the spectra of individual vibrational levels. Because the split-operator thermofield dynamics on a full tensor-product grid is restricted to low-dimensional systems, we briefly discuss how the accessible dimensionality can be increased by various techniques developed for the zero-temperature split-operator Fourier method.

17.
Curr Microbiol ; 81(8): 232, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38898312

ABSTRACT

Delftia has been separated from freshwater, sludge, and soil and has emerged as a novel opportunistic pathogen in the female vagina. However, the genomic characteristics, pathogenicity, and biotechnological properties still need to be comprehensively investigated. In this study, a Delftia strain was isolated from the vaginal discharge of a 43-year-old female with histologically confirmed cervical intraepithelial neoplasm (CIN III), followed by whole-genome sequencing. Phylogenetic analysis and average nucleotide identity (ANI) analysis demonstrated that it belongs to Delftia lacustris, named D. lacustris strain LzhVag01. LzhVag01 was sensitive to ß-lactams, macrolides, and tetracyclines but exhibited resistance to lincoamines, nitroimidazoles, aminoglycosides, and fluoroquinolones. Its genome is a single, circular chromosome of 6,740,460 bp with an average GC content of 66.59%. Whole-genome analysis identified 16 antibiotic resistance-related genes, which match the antimicrobial susceptibility profile of this strain, and 11 potential virulence genes. These pathogenic factors may contribute to its colonization in the vaginal environment and its adaptation and accelerate the progression of cervical cancer. This study sequenced and characterized the whole-genome of Delftia lacustris isolated from vaginal discharge, which provides investigators and clinicians with valuable insights into this uncommon species.


Subject(s)
Delftia , Genome, Bacterial , Vaginal Discharge , Delftia/classification , Delftia/drug effects , Delftia/genetics , Delftia/pathogenicity , Genome, Bacterial/genetics , Vaginal Discharge/microbiology , Humans , Female , Adult , Phylogeny , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial/genetics , Virulence Factors/genetics , Species Specificity
18.
Drug Resist Updat ; 66: 100903, 2023 01.
Article in English | MEDLINE | ID: mdl-36463808

ABSTRACT

Breast cancer stem-like cells (BCSCs) have been suggested as the underlying cause of tumor recurrence, metastasis and drug resistance in triple-negative breast cancer (TNBC). Here, we report the discovery and biological evaluation of a highly potent small-molecule antagonist of exportin-1, LFS-1107. We ascertained that exportin-1 (also named as CRM1) is a main cellular target of LFS-1107 by nuclear export functional assay, bio-layer interferometry binding assay and C528S mutant cell line. We found that LFS-1107 significantly inhibited TNBC tumor cells at low-range nanomolar concentration and LFS-1107 can selectively eliminate CD44+CD24- enriched BCSCs. We demonstrated that LFS-1107 can induce the nuclear retention of Survivin and consequent strong suppression of STAT3 transactivation abilities and the expression of downstream stemness regulators. Administration of LFS-1107 can strongly inhibit tumor growth in mouse xenograft model and eradicate BCSCs in residual tumor tissues. Moreover, LFS-1107 can significantly ablate the patient-derived tumor organoids (PDTOs) of TNBC as compared to a few approved cancer drugs. Lastly, we revealed that LFS-1107 can enhance the killing effects of chemotherapy drugs and downregulate multidrug resistance related protein targets. These new findings provide preclinical evidence of defining LFS-1107 as a promising therapeutic agent to deplete BCSCs for the treatment of TNBC.


Subject(s)
Antineoplastic Agents , Breast Neoplasms , Triple Negative Breast Neoplasms , Humans , Animals , Mice , Female , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/genetics , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/metabolism , Karyopherins/genetics , Karyopherins/metabolism , Karyopherins/pharmacology , Neoplastic Stem Cells , Cell Line, Tumor , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Cell Proliferation , Hyaluronan Receptors/genetics , Hyaluronan Receptors/metabolism , Hyaluronan Receptors/therapeutic use , CD24 Antigen/genetics , CD24 Antigen/metabolism , CD24 Antigen/therapeutic use
19.
World J Surg Oncol ; 22(1): 198, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39068445

ABSTRACT

BACKGROUND: Neoadjuvant therapy (NT) has increased survival rates for patients with locally advanced esophageal cancer (EC), but estimating the impact of NT treatment prior to surgery is still very difficult. METHODS: A retrospective study of the clinical information of 150 patients with locally advanced EC who got NT at Qilu Hospital of Shandong University between June 2018 and June 2023. Patients were randomized into training and internal validation groups at a 3:1 ratio. Furthermore, an external validation cohort comprised 38 patients who underwent neoadjuvant therapy at Qianfoshan Hospital in the Shandong Province between June 2021 and June 2023. Independent risk factors were identified using univariate and multivariate logistic regression (forward stepwise regression). Predictive models and dynamic web nomograms were developed by integrating these risk factors. RESULTS: A total of 188 patients with locally advanced EC were enrolled, of whom 118 achieved stage I of neoadjuvant pathologic TNM (ypTNM) after receiving NT and 129 achieved grades 0-1 in the tumor regression grade (TRG). Logistic regression analysis identified five independent predictors of TRG grades 0-1: pulmonary function tests (PFT), prognostic nutritional index (PNI), triglyceride (TG) levels, squamous cell carcinoma antigen (SCC-Ag) levels, and combination immunotherapy. The areas under the receiver operating characteristic (ROC) curves for the training, internal validation, and external validation groups were 0.87, 0.75, and 0.80, respectively. Meanwhile, two independent predictors of stage I of ypTNM were identified: prealbumin (PA) and SCC antigen. The areas under the ROC curves for the training, internal validation, and external validation groups were 0.78, 0.67, and 0.70, respectively. The Hosmer-Lemeshow test for both predictive models showed excellent calibration, with well-fitted calibration curves. Decision curve analysis (DCA) and clinical impact curves (CIC) have demonstrated that nomograms are of clinical utility. CONCLUSION: The nomograms performed well in predicting the likelihood of stage I of ypTNM and TRG grade 0-1 after NT in patients with locally advanced EC. It helps thoracic surgeons to predict the sensitivity of patients to NT before surgery, which enables precise treatment of patients with locally advanced EC.


Subject(s)
Esophageal Neoplasms , Neoadjuvant Therapy , Neoplasm Staging , Nomograms , Humans , Esophageal Neoplasms/pathology , Esophageal Neoplasms/therapy , Male , Female , Neoadjuvant Therapy/methods , Middle Aged , Retrospective Studies , Prognosis , Follow-Up Studies , Aged , Neoplasm Grading , Esophagectomy
20.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Article in English | MEDLINE | ID: mdl-34531299

ABSTRACT

Habituation and sensitization (nonassociative learning) are among the most fundamental forms of learning and memory behavior present in organisms that enable adaptation and learning in dynamic environments. Emulating such features of intelligence found in nature in the solid state can serve as inspiration for algorithmic simulations in artificial neural networks and potential use in neuromorphic computing. Here, we demonstrate nonassociative learning with a prototypical Mott insulator, nickel oxide (NiO), under a variety of external stimuli at and above room temperature. Similar to biological species such as Aplysia, habituation and sensitization of NiO possess time-dependent plasticity relying on both strength and time interval between stimuli. A combination of experimental approaches and first-principles calculations reveals that such learning behavior of NiO results from dynamic modulation of its defect and electronic structure. An artificial neural network model inspired by such nonassociative learning is simulated to show advantages for an unsupervised clustering task in accuracy and reducing catastrophic interference, which could help mitigate the stability-plasticity dilemma. Mott insulators can therefore serve as building blocks to examine learning behavior noted in biology and inspire new learning algorithms for artificial intelligence.


Subject(s)
Algorithms , Aplysia/physiology , Artificial Intelligence , Insulator Elements , Neural Networks, Computer , Nickel/chemistry , Synapses/physiology , Animals , Electrons , Models, Neurological , Neuronal Plasticity
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