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1.
Cell ; 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38657602

ABSTRACT

Antigen presentation defects in tumors are prevalent mechanisms of adaptive immune evasion and resistance to cancer immunotherapy, whereas how tumors evade innate immunity is less clear. Using CRISPR screens, we discovered that IGSF8 expressed on tumors suppresses NK cell function by interacting with human KIR3DL2 and mouse Klra9 receptors on NK cells. IGSF8 is normally expressed in neuronal tissues and is not required for cell survival in vitro or in vivo. It is overexpressed and associated with low antigen presentation, low immune infiltration, and worse clinical outcomes in many tumors. An antibody that blocks IGSF8-NK receptor interaction enhances NK cell killing of malignant cells in vitro and upregulates antigen presentation, NK cell-mediated cytotoxicity, and T cell signaling in vivo. In syngeneic tumor models, anti-IGSF8 alone, or in combination with anti-PD1, inhibits tumor growth. Our results indicate that IGSF8 is an innate immune checkpoint that could be exploited as a therapeutic target.

2.
Cell Death Dis ; 15(4): 279, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38637504

ABSTRACT

Cisplatin (DDP)-based chemoradiotherapy is one of the standard treatments for nasopharyngeal carcinoma (NPC). However, the sensitivity and side effects of DDP to patients remain major obstacles for NPC treatment. This research aimed to study DDP sensitivity regulated by cancer-associated fibroblasts (CAFs) through modulating ferroptosis. We demonstrated that DDP triggered ferroptosis in NPC cells, and it inhibited tumor growth via inducing ferroptosis in xenograft model. CAFs secreted high level of FGF5, thus inhibiting DDP-induced ferroptosis in NPC cells. Mechanistically, FGF5 secreted by CAFs directly bound to FGFR2 in NPC cells, leading to the activation of Keap1/Nrf2/HO-1 signaling. Rescued experiments indicated that FGFR2 overexpression inhibited DDP-induced ferroptosis, and CAFs protected against DDP-induced ferroptosis via FGF5/FGFR2 axis in NPC cells. In vivo data further showed the protective effects of FGF5 on DDP-triggered ferroptosis in NPC xenograft model. In conclusion, CAFs inhibited ferroptosis to decrease DDP sensitivity in NPC through secreting FGF5 and activating downstream FGFR2/Nrf2 signaling. The therapeutic strategy targeting FGF5/FGFR2 axis from CAFs might augment DDP sensitivity, thus decreasing the side effects of DDP in NPC treatment.


Subject(s)
Cancer-Associated Fibroblasts , Ferroptosis , Nasopharyngeal Neoplasms , Humans , Cisplatin/pharmacology , Cisplatin/therapeutic use , Nasopharyngeal Carcinoma/drug therapy , Nasopharyngeal Carcinoma/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Cancer-Associated Fibroblasts/metabolism , NF-E2-Related Factor 2/metabolism , Cell Line, Tumor , Nasopharyngeal Neoplasms/pathology , Drug Resistance, Neoplasm , Receptor, Fibroblast Growth Factor, Type 2/genetics , Receptor, Fibroblast Growth Factor, Type 2/metabolism , Fibroblast Growth Factor 5
3.
Mol Cancer ; 23(1): 20, 2024 01 22.
Article in English | MEDLINE | ID: mdl-38254110

ABSTRACT

The incidence of nasopharyngeal carcinoma (NPC) exhibits significant variations across different ethnic groups and geographical regions, with Southeast Asia and North Africa being endemic areas. Of note, Epstein-Barr virus (EBV) infection is closely associated with almost all of the undifferentiated NPC cases. Over the past three decades, radiation therapy and chemotherapy have formed the cornerstone of NPC treatment. However, recent advancements in immunotherapy have introduced a range of promising approaches for managing NPC. In light of these developments, it has become evident that a deeper understanding of the tumor microenvironment (TME) is crucial. The TME serves a dual function, acting as a promoter of tumorigenesis while also orchestrating immunosuppression, thereby facilitating cancer progression and enabling immune evasion. Consequently, a comprehensive comprehension of the TME and its intricate involvement in the initiation, progression, and metastasis of NPC is imperative for the development of effective anticancer drugs. Moreover, given the complexity of TME and the inter-patient heterogeneity, personalized treatment should be designed to maximize therapeutic efficacy and circumvent drug resistance. This review aims to provide an in-depth exploration of the TME within the context of EBV-induced NPC, with a particular emphasis on its pivotal role in regulating intercellular communication and shaping treatment responses. Additionally, the review offers a concise summary of drug resistance mechanisms and potential strategies for their reversal, specifically in relation to chemoradiation therapy, targeted therapy, and immunotherapy. Furthermore, recent advances in clinical trials pertaining to NPC are also discussed.


Subject(s)
Epstein-Barr Virus Infections , Nasopharyngeal Neoplasms , Humans , Epstein-Barr Virus Infections/complications , Nasopharyngeal Carcinoma/drug therapy , Tumor Microenvironment , Herpesvirus 4, Human , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/genetics
4.
Cell Death Dis ; 14(12): 852, 2023 12 21.
Article in English | MEDLINE | ID: mdl-38129408

ABSTRACT

Reprogramming of macrophages toward an M1 phenotype is a novel strategy to induce anticancer immunity. However, the regulatory mechanisms of M1 macrophage polarization and its functional roles in nasopharyngeal carcinoma (NPC) progression need to be further explored. Here we found that SPLUNC1 was highly expressed and responsible for M1 macrophage polarization. JAK/STATs pathway activation was involved in SPLUNC1-mediated M1 macrophage polarization. Importantly, regulation of SPLUNC1 in macrophages affected CM-mediated influence on NPC cell proliferation and migration. Mechanistically, USP7 deubiquitinated and stabilized TRIM24, which promoted SPLUNC1 expression via recruitment of STAT3 in M1 macrophages. Depletion of TRIM24 inhibited M1 macrophage polarization, which facilitated NPC cell growth and migration. However, over-expression of USP7 exhibited the opposite results and counteracted the tumorigenic effect of TRIM24 silencing. Finally, the growth and metastasis of NPC cells in vivo were repressed by USP7-induced M1 macrophage polarization via modulating TRIM24/SPLUNC1 axis. USP7 delayed NPC progression via promoting macrophage polarization toward M1 through regulating TRIM24/SPLUNC1 pathway, providing evidence for the development of effective antitumor immunotherapies for NPC.


Subject(s)
Macrophages , Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/genetics , Nasopharyngeal Carcinoma/metabolism , Ubiquitin-Specific Peptidase 7/metabolism , Macrophages/metabolism , Nasopharyngeal Neoplasms/pathology , Macrophage Activation , Carrier Proteins/metabolism
5.
J Phys Chem B ; 127(45): 9813-9821, 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37968938

ABSTRACT

Organic dyads with intramolecular charge-transfer (ICT) character are emerging as viable and more sustainable photocatalysts than metal-based complexes. Herein, a carbazole- and naphthalimide-based organic dyad (Cz-NI) was designed as an efficient organic photocatalyst for the direct C(sp3)-H carbamoylation of saturated aza-heterocycles. Aiming at understanding the effect of environment, especially the solvent polarity on photocatalysis performance, the excited-state dynamics of Cz-NI in different polar solvents were studied by femtosecond (fs) and nanosecond (ns) time-resolved transient absorption (TA) spectroscopy. Fs-TA measurements indicate that the formation of an intramolecular charge separation (ICS) state with twisted structural feature in polar solvents is driven and stabilized by solvation dynamics. Combined with chemical calculations, we found that orbital decoupling, poor conjugation between Cz and NI groups due to intramolecular torsional motion and transition moments associated with ICT emission, limits excited-state deactivation through radiation and nonradiation transition to the ground state. In addition, the orthogonal π-system of the ICS state enables the efficient spin-orbit, charge-transfer intersystem crossing to a triplet state, which is localized on the NI group. Spectroscopic and computational results reveal the formation of an ICS state at an appropriate energy that enables the population of the triplet state with high quantum yield, and the localized triplet state has long lifetime and high reduction potential for subsequent reactions. Therefore, solvent-solute interaction, especially the solvation-coupled excited-state structural relaxation, is the main factor that the photocatalysis efficiency of Cz-NI has a significant polarity correlation.

6.
Int Immunopharmacol ; 122: 110629, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37451020

ABSTRACT

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a head and neck malignant tumor with a high incidence and recurrence rate. The crosstalk between ferroptosis and tumor-associated macrophages (TAMs) is thought to have major implications in interfering with cancers. We intended to explore the effect of acyl-CoA synthetase long-chain family member 4 (ACSL4) on the pathogenesis of NPC via ferroptosis and TAMs. METHODS: Differential genes in NPC patients were analyzed using publicly available databases, and the ferroptosis-related gene ACSL4 was identified. Expression of ACSL4 in NPC cell lines and xenografted mice was examined. Colony formation, cell proliferation, migration, and invasion were assessed. The abundance of epithelial-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin, and Vimentin) was confirmed. Lipid peroxidation levels and related markers were measured. Clophosome was administered to determine the role of TAMs in NPC mice. RESULTS: Low levels of ACSL4 were observed in NPC patients and CNE-2 and 5-8F cells. Erastin (a ferroptosis inducer) and ACSL4 increased lipid peroxidation, decreased cell viability, colony formation, cell proliferation, migration and invasion, and inhibited EMT. Moreover, Erastin and ACSL4 promoted M2 to M1 macrophage polarization. The effects of erastin and ACSL4 were additive. Ferrostatin-1, an inhibitor of ferroptosis, exerted the opposite effect and reversed the beneficial effects of ACSL4 overexpression. In xenograft mice, ACSL4 and clophosome hindered the growth of NPC, and extra clophosome slightly enhanced the antitumor effect of ACSL4. CONCLUSION: Our findings indicated that ACSL4 inhibited the pathogenesis of NPC, at least through crosstalk between ferroptosis and macrophages, providing potential direction for NPC therapy.


Subject(s)
Ferroptosis , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms , Animals , Humans , Mice , Carcinogenesis , Cell Line, Tumor , Macrophages/pathology , Nasopharyngeal Carcinoma/genetics , Nasopharyngeal Neoplasms/genetics
7.
Front Pharmacol ; 14: 1037925, 2023.
Article in English | MEDLINE | ID: mdl-36874007

ABSTRACT

TRPV1 is a non-selective channel receptor widely expressed in skin tissues, including keratinocytes, peripheral sensory nerve fibers and immune cells. It is activated by a variety of exogenous or endogenous inflammatory mediators, triggering neuropeptide release and neurogenic inflammatory response. Previous studies have shown that TRPV1 is closely related to the occurrence and/or development of skin aging and various chronic inflammatory skin diseases, such as psoriasis, atopic dermatitis, rosacea, herpes zoster, allergic contact dermatitis and prurigo nodularis. This review summarizes the structure of the TRPV1 channel and discusses the expression of TRPV1 in the skin as well as its role of TRPV1 in skin aging and inflammatory skin diseases.

8.
Chem Commun (Camb) ; 59(14): 2003-2006, 2023 Feb 14.
Article in English | MEDLINE | ID: mdl-36723060

ABSTRACT

A mild metal-free C-N bond activation strategy for the direct conversion of inert tertiary amines with acyl chlorides into tertiary amides via organic photoredox catalysis is presented. In this protocol, a novel organic photocatalyst (Cz-NI-Ph) that showed excellent catalytic performance during C-N bond cleavage is developed. Moreover, this reaction features green and mild conditions, broad substrate scope, and readily available raw materials.

9.
Anticancer Drugs ; 34(2): 227-237, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36305358

ABSTRACT

The occurrence and progression of colorectal cancer (CRC) are closely related to intestinal microecological disorders. Butyrate, the representative of short chain fatty acids, possess anti-inflammatory and antioxidant effects, and its antitumor effect has been gradually paid attention to. In this study, azoxymethane/dextran sodium sulfate induced mouse CRC model was used to explore the role and mechanism of butyrate in regulating colon cancer and its intestinal microecological balance. Outcomes exhibited that butyrate alleviated weight loss, disease activity index, and survival in CRC mice and inhibited tumor number and progression. Further research revealed that butyrate restrained the aggregation of harmful while promoting the colonization of beneficial flora, such as Actinobacteriota, Bifidobacteriales and Muribaculacea through 16S rDNA sequence analysis. This study confirmed that butyrate can ameliorate CRC by repairing intestinal microecology, providing ideas and evidence for chemical prophylactic agents, such as butyrate to remedy tumors and regulate tumor microbiota.


Subject(s)
Colonic Neoplasms , Colorectal Neoplasms , Mice , Animals , Butyrates/adverse effects , Disease Models, Animal , Azoxymethane/adverse effects , Dextran Sulfate/adverse effects , Mice, Inbred C57BL , Colorectal Neoplasms/pathology
10.
Sensors (Basel) ; 22(20)2022 Oct 20.
Article in English | MEDLINE | ID: mdl-36298363

ABSTRACT

Traditional soil nitrogen detection methods have the characteristics of being time-consuming and having an environmental pollution effect. We urgently need a rapid, easy-to-operate, and non-polluting soil nitrogen detection technology. In order to quickly measure the nitrogen content in soil, a new method for detecting the nitrogen content in soil is presented by using a near-infrared spectrum technique and random forest regression (RF). Firstly, the experiment took the soil by the Xunsi River in the area of Hubei University of Technology as the research object, and a total of 143 soil samples were collected. Secondly, NIR spectral data from 143 soil samples were acquired, and chemical and physical methods were used to determine the content of nitrogen in the soil. Thirdly, the raw spectral data of soil samples were denoised by preprocessing. Finally, a forecast model for the soil nitrogen content was developed by using the measured values of components and modeling algorithms. The model was optimized by adjusting the changes in the model parameters and Gini coefficient (∆Gini), and the model was compared with the back propagation (BP) and support vector machine (SVM) models. The results show that: the RF model modeling set prediction R2C is 0.921, the RMSEC is 0.115, the test set R2P is 0.83, and the RMSEP is 0.141; the detection of the soil nitrogen content can be realized by using a near-infrared spectrum technique and random forest algorithm, and its prediction accuracy is better than that of the BP and SVM models; using ∆ Gini to optimize the RF modeling data, the spectral information of the soil nitrogen content can be extracted, and the data redundancy can be reduced effectively.


Subject(s)
Soil , Spectroscopy, Near-Infrared , Soil/chemistry , Spectroscopy, Near-Infrared/methods , Nitrogen/analysis , Support Vector Machine , Algorithms , Least-Squares Analysis
11.
Waste Manag ; 153: 61-71, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36055176

ABSTRACT

The recycling of valuable metals from spent lithium-ion batteries (LIBs) has great significance for environmental protection and resource conservation. In this paper, a low-temperature clean chlorination roasting-water leaching process was proposed to simultaneously extract Li, Ni, Co and Mn from cathode material (NCM) of spent LIBs. The temperature range of chlorination roasting was determined by thermodynamic analysis to be 250-600 °C. The effect of some factors on the conversion of valuable metals in the process of chlorination roasting and water leaching was systematically studied. The results showed that more than 98 % of Li, Co, Ni and Mn could be extracted under optimized chlorination roasting and water leaching conditions. The chlorination roasting mechanism and phase transformation evolution was determined by means of thermodynamic analysis, TG-DTA, XRD, SEM and EDS. The extraction of valuable metals was realized by the reaction of the metal oxides produced by the decomposition of NCM with NH4Cl or its evolved HCl to form water-soluble metal chlorides or chlorinated metal-ammonium complexes. The chlorination technique using NH4Cl provided an effective and clean approach for the simultaneous extraction of Li, Co, Ni and Mn from spent LIBs.

12.
Med Oncol ; 39(12): 214, 2022 Sep 29.
Article in English | MEDLINE | ID: mdl-36175598

ABSTRACT

Nasopharyngeal carcinoma (NPC) is one of the aggressive malignant tumors with high mortality, and the proliferation of myeloid-derived suppressor cells (MDSCs) could promote the metastasis of NPC through inhibiting the function of T cells. Meanwhile, SPLUNC1 was known to inhibit the malignant behavior of NPC cells, while the detailed function of SPLUNC1 in LPS-modified immune microenvironment of NPC remains unclear. To assess the impact of SPLUNC1 in immune microenvironment during the progression of NPC, NPC cells were exposed to LPS and then co-cultured with MDSCs for 48 h. RT-qPCR and western blot were performed to evaluate the mRNA and protein level of SPLUNC1, CXCL-2 and CXCR-2, respectively. The level of IL-1ß, IL-6, TNF-α, PD-L1, Arg-1 and iNOS were tested by ELISA. Meanwhile, the expression of CD33+ was tested by flow cytometry. The expression of CXCL-2 and CXCR-2 in NPC cells was higher, compared to that in NP69 cells. In contrast, SPLUNC1 level in NPC cells was much lower than that in NP69 cells. SPLUNC1 level was negatively correlated with CXCL-2 and CXCR-2. Overexpression of SPLUNC1 reversed LPS-induced inflammatory responses and proliferation in NPC cells. In addition, SPLUNC1 upregulation could reverse LPS-induced proliferation of MDSCs in tumor microenvironment. Meanwhile, SPLUNC1 overexpression could regulate CXCL-2/CXCR-2 axis through decreasing CXCL-2 and CXCR-2 protein and mRNA expression. SPLUNC1 regulates LPS-induced progression of nasopharyngeal carcinoma and proliferation of MDSCs. Thus, our study might provide a theoretical basis for discovering new strategies against NPC.


Subject(s)
Glycoproteins/metabolism , Myeloid-Derived Suppressor Cells , Nasopharyngeal Neoplasms , Phosphoproteins/metabolism , B7-H1 Antigen , Cell Proliferation , Humans , Interleukin-6 , Lipopolysaccharides/pharmacology , Nasopharyngeal Carcinoma , Tumor Microenvironment , Tumor Necrosis Factor-alpha
13.
Mol Immunol ; 149: 13-26, 2022 09.
Article in English | MEDLINE | ID: mdl-35696849

ABSTRACT

Multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) are demyelinating neuroinflammatory diseases identified by the accumulation and aggregation of misfolded proteins in the brain. The Sel1L-Hrd1 complex comprising endoplasmic reticulum associated degradation (ERAD) is an ER-protein quality control system (ERQC) in the cell. Unfortunately, the contribution of ERAD to the development of these diseases has not been well explored. In this study, we used mice with a conditional deletion (KO) of Sel1L in T cells to dissect the role of ERAD on T cells and its contribution to the development of EAE. The results showed that Sel1L KO mice developed more severe EAE than the control wild type (WT) mice. Although, no obvious effects on peripheral T cells in steady state, more CD44-CD25+ double-negative stage 3 (DN3) cells were detected in the thymus. Moreover, Sel1L deficiency promoted the differentiation of Th1 and Th17 cells and upregulated the proliferation and apoptosis of CD4 T cells in vitro. Regarding the mechanism analyzed by RNA sequencing, 437 downregulated genes and 271 upregulated genes were detected in Sel1L deletion CD4 T cells, which covered the activation, proliferation, differentiation and apoptosis of these T cells. Thus, this study declared that the dysfunction of Sel1L in ERAD in T cells exacerbated the severity of EAE and indicated the important role of ERQC in maintaining immune homeostasis in the central nervous system.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Animals , Cell Differentiation , Encephalomyelitis, Autoimmune, Experimental/genetics , Endoplasmic Reticulum-Associated Degradation , Mice , Mice, Inbred C57BL , Proteins/genetics , Th1 Cells/metabolism , Th17 Cells/metabolism , Ubiquitin-Protein Ligases/metabolism
14.
Front Immunol ; 13: 870952, 2022.
Article in English | MEDLINE | ID: mdl-35634308

ABSTRACT

Transient receptor potential vanilloid1 (TRPV1) was primarily expressed in sensory neurons, and could be activated by various physical and chemical factors, resulting in the flow of extracellular Ca2+ into cells. Accumulating data suggest that the TRPV1 is expressed in some immune cells and is a novel regulator of the immune system. In this review, we highlight the structure and biological features of TRPV1 channel. We also summarize recent findings on its role in modulating T cell activation and differentiation as well as its protective effect in T cell-mediated inflammatory diseases and potential mechanisms.


Subject(s)
Sesamum , Transient Receptor Potential Channels , Sensory Receptor Cells , T-Lymphocytes , TRPV Cation Channels
15.
Chem Commun (Camb) ; 58(17): 2882-2885, 2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35133366

ABSTRACT

Here we describe a metal-free amino-heteroarylation of unactivated olefins via organic photoredox catalysis, providing a concise and efficient approach for the rapid synthesis of various δ (ß, ε)-amino ketones under mild conditions. This protocol demonstrates that the new photocatalyst Cz-NI developed by our group has an excellent photoredox catalytic performance. Finally, a series of mechanistic experiments and DFT calculations indicate that this transformation undergoes a photoredox catalytic sequential radical addition/functional group migration process.

16.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Article in English | MEDLINE | ID: mdl-35031563

ABSTRACT

Drugs that block the activity of the methyltransferase EZH2 are in clinical development for the treatment of non-Hodgkin lymphomas harboring EZH2 gain-of-function mutations that enhance its polycomb repressive function. We have previously reported that EZH2 can act as a transcriptional activator in castration-resistant prostate cancer (CRPC). Now we show that EZH2 inhibitors can also block the transactivation activity of EZH2 and inhibit the growth of CRPC cells. Gene expression and epigenomics profiling of cells treated with EZH2 inhibitors demonstrated that in addition to derepressing gene expression, these compounds also robustly down-regulate a set of DNA damage repair (DDR) genes, especially those involved in the base excision repair (BER) pathway. Methylation of the pioneer factor FOXA1 by EZH2 contributes to the activation of these genes, and interaction with the transcriptional coactivator P300 via the transactivation domain on EZH2 directly turns on the transcription. In addition, CRISPR-Cas9-mediated knockout screens in the presence of EZH2 inhibitors identified these BER genes as the determinants that underlie the growth-inhibitory effect of EZH2 inhibitors. Interrogation of public data from diverse types of solid tumors expressing wild-type EZH2 demonstrated that expression of DDR genes is significantly correlated with EZH2 dependency and cellular sensitivity to EZH2 inhibitors. Consistent with these findings, treatment of CRPC cells with EZH2 inhibitors dramatically enhances their sensitivity to genotoxic stress. These studies reveal a previously unappreciated mechanism of action of EZH2 inhibitors and provide a mechanistic basis for potential combination cancer therapies.


Subject(s)
DNA Damage/genetics , DNA Damage/physiology , Enhancer of Zeste Homolog 2 Protein/genetics , Enhancer of Zeste Homolog 2 Protein/metabolism , Transcriptional Activation , CRISPR-Cas Systems , Cell Line, Tumor , DNA Repair/genetics , DNA Repair/physiology , Epigenesis, Genetic , Gene Expression Regulation, Neoplastic , Gene Knockout Techniques , Hepatocyte Nuclear Factor 3-alpha/genetics , Hepatocyte Nuclear Factor 3-alpha/metabolism , Humans , Male , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/metabolism
17.
Chem Commun (Camb) ; 57(97): 13158-13161, 2021 Dec 07.
Article in English | MEDLINE | ID: mdl-34812446

ABSTRACT

A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Brønsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.

18.
Nat Cell Biol ; 23(11): 1187-1198, 2021 11.
Article in English | MEDLINE | ID: mdl-34737445

ABSTRACT

How cancer cells adapt to evade the therapeutic effects of drugs targeting oncogenic drivers is poorly understood. Here we report an epigenetic mechanism leading to the adaptive resistance of triple-negative breast cancer (TNBC) to fibroblast growth factor receptor (FGFR) inhibitors. Prolonged FGFR inhibition suppresses the function of BRG1-dependent chromatin remodelling, leading to an epigenetic state that derepresses YAP-associated enhancers. These chromatin changes induce the expression of several amino acid transporters, resulting in increased intracellular levels of specific amino acids that reactivate mTORC1. Consistent with this mechanism, addition of mTORC1 or YAP inhibitors to FGFR blockade synergistically attenuated the growth of TNBC patient-derived xenograft models. Collectively, these findings reveal a feedback loop involving an epigenetic state transition and metabolic reprogramming that leads to adaptive therapeutic resistance and provides potential therapeutic strategies to overcome this mechanism of resistance.


Subject(s)
Antineoplastic Agents/pharmacology , Chromosomal Proteins, Non-Histone/metabolism , Drug Resistance, Neoplasm , Phenylurea Compounds/pharmacology , Pyrimidines/pharmacology , Receptors, Fibroblast Growth Factor/antagonists & inhibitors , Transcription Factors/metabolism , Triple Negative Breast Neoplasms/drug therapy , YAP-Signaling Proteins/metabolism , Amino Acids/metabolism , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Cell Line, Tumor , Chromatin Assembly and Disassembly , Chromosomal Proteins, Non-Histone/genetics , DNA Helicases/genetics , DNA Helicases/metabolism , Drug Resistance, Neoplasm/genetics , Drug Synergism , Epigenesis, Genetic , Female , Gene Expression Regulation, Neoplastic , Humans , Mechanistic Target of Rapamycin Complex 1/antagonists & inhibitors , Mechanistic Target of Rapamycin Complex 1/genetics , Mechanistic Target of Rapamycin Complex 1/metabolism , Molecular Targeted Therapy , Multiprotein Complexes , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Receptors, Fibroblast Growth Factor/metabolism , Signal Transduction , Transcription Factors/genetics , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Xenograft Model Antitumor Assays , YAP-Signaling Proteins/antagonists & inhibitors , YAP-Signaling Proteins/genetics
19.
Org Lett ; 23(22): 8942-8946, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34757741

ABSTRACT

Herein, we report a photoinduced dehydrogenation/(3+2) cycloaddition reaction by merging organic photoredox and Lewis acid catalysis, providing a straightforward and efficient approach for directly installing a benzofuran skeleton on the saturated aza-heterocycles. In this protocol, we also describe a novel organic photocatalyst (t-Bu-DCQ) with the advantages of a wider redox potential, easy synthesis, and a low price. Furthermore, the stepwise activation mechanism of dual C(sp3)-H bonds was demonstrated by a series of experimental and computational studies.

20.
Cell ; 184(21): 5357-5374.e22, 2021 10 14.
Article in English | MEDLINE | ID: mdl-34582788

ABSTRACT

Despite remarkable clinical efficacy of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits for triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that deletion of the E3 ubiquitin ligase Cop1 in cancer cells decreases secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances anti-tumor immunity, and strengthens ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed that Cop1 functions through proteasomal degradation of the C/ebpδ protein. The Cop1 substrate Trib2 functions as a scaffold linking Cop1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. In addition, deletion of the E3 ubiquitin ligase Cop1 in cancer cells stabilizes C/ebpδ to suppress expression of macrophage chemoattractant genes. Our integrated approach implicates Cop1 as a target for improving cancer immunotherapy efficacy in TNBC by regulating chemokine secretion and macrophage infiltration in the tumor microenvironment.


Subject(s)
Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Immunotherapy , Macrophages/enzymology , Neoplasms/immunology , Neoplasms/therapy , Nuclear Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , CCAAT-Enhancer-Binding Protein-delta/metabolism , CRISPR-Associated Protein 9/metabolism , Cell Line, Tumor , Chemokines/metabolism , Chemotaxis , Disease Models, Animal , Gene Library , Humans , Immune Evasion , Mice, Inbred BALB C , Mice, Inbred C57BL , Proteolysis , Substrate Specificity , Triple Negative Breast Neoplasms/immunology , Triple Negative Breast Neoplasms/therapy
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