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1.
J Am Soc Mass Spectrom ; 35(9): 2090-2101, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39136314

ABSTRACT

The increasing need for mass spectrometric analysis of RNA molecules calls for a better understanding of their gas-phase fragmentation behaviors. In this study, we investigate the effect of terminal phosphate groups on the fragmentation spectra of RNA oligonucleotides (oligos) using high-resolution mass spectrometry (MS). Negative-ion mode collision-induced dissociation (CID) and higher-energy collisional dissociation (HCD) were carried out on RNA oligos containing a terminal phosphate group on either end, both ends, or neither end. We find that terminal phosphate groups affect the fragmentation behavior of RNA oligos in a way that is dependent on the precursor charge state and the oligo length. Specifically, for precursor ions of RNA oligos of the same sequence, those with 5'- or 3'-phosphate, or both, have a higher charge state distribution and lose the phosphate group(s) in the form of a neutral (H3PO4 or HPO3) or an anion ([H2PO4]- or [PO3]-) upon CID or HCD. Such a neutral or charged loss is most conspicuous for precursor ions of an intermediate charge state, e.g., 3- for 4-nt oligos or 4- and 5- for 8-nt oligos. This decreases the intensity of sequencing ions (a-, a-B, b-, c-, d-, w-, x-, y-, z-ions) and hence is unfavorable for sequencing by CID or HCD. Removal of terminal phosphate groups by calf intestinal alkaline phosphatase improved MS analysis of RNA oligos. Additionally, the intensity of a fragment ion at m/z 158.925, which we identified as a dehydrated pyrophosphate anion ([HP2O6]-), is markedly increased by the presence of a terminal phosphate group. These findings expand the knowledge base necessary for software development for MS analysis of RNA.


Subject(s)
Anions , Phosphates , RNA , Anions/chemistry , Phosphates/chemistry , RNA/chemistry , RNA/analysis , Oligonucleotides/chemistry , Oligonucleotides/analysis , Mass Spectrometry/methods , Tandem Mass Spectrometry/methods
2.
Molecules ; 29(16)2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39202911

ABSTRACT

In this work, we report the synthesis of a new thiosemicarbazone-based drug of N'-(di(pyridin-2-yl)methylene)-4-(thiazol-2-yl)piperazine-1-carbothiohydrazide (HL) featuring a thiazole spectator for efficient coordination with Cu(II) to give [CuCl(L)]2 (1) and [Cu(NO3)(L)]2 (2). Both 1 and 2 exhibit dimeric structures ascribed to the presence of di-2-pyridylketone moieties that demonstrate dual functions of chelation and intermolecular bridging. HL, 1, and 2 are highly toxic against hepatocellular carcinoma cell lines Hep-G2, PLC/PRF/5, and HuH-7 with half maximal inhibitory concentration (IC50) values as low as 3.26 nmol/mL (HL), 2.18 nmol/mL (1), and 2.54 × 10-5 nmol/mL (2) for PLC/PRF/5. While the free ligand HL may elicit its anticancer effect via the sequestration of bio-relevant metal ions (i.e., Fe3+ and Cu2+), 1 and 2 are also capable of generating cytotoxic reactive oxygen species (ROS) to inhibit cancer cell proliferation. Our preliminary pharmacokinetic studies revealed that oral administration (per os, PO) of HL has a significantly longer half-life t1/2 of 21.61 ± 9.4 h, nearly doubled as compared with that of the intravenous (i.v.) administration of 11.88 ± 1.66 h, certifying HL as an effective chemotherapeutic drug via PO administration.


Subject(s)
Antineoplastic Agents , Copper , Thiazoles , Thiosemicarbazones , Thiosemicarbazones/chemistry , Thiosemicarbazones/pharmacology , Thiosemicarbazones/pharmacokinetics , Humans , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Copper/chemistry , Thiazoles/chemistry , Thiazoles/pharmacology , Thiazoles/pharmacokinetics , Cell Line, Tumor , Biological Availability , Animals , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/pharmacokinetics , Administration, Oral , Molecular Structure , Hep G2 Cells , Reactive Oxygen Species/metabolism
3.
J Colloid Interface Sci ; 678(Pt A): 141-151, 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39182388

ABSTRACT

Luminescent materials with engineered optical properties play an important role in anti-counterfeiting and information security technology. However, conventional luminescent coding is limited by fluorescence color or intensity, and high-level multi-dimensional luminescent encryption technology remains a critically challenging goal in different scenarios. To improve the encoding capacity, we present an optical multiplexing concept by synchronously manipulating the emission color and decay lifetimes of room-temperature phosphorescence materials at molecular level. Herein, we devise a family of zero-dimensional (0D) hybrid metal halides by combining organic phosphonium cations and metal halide tetrahedral anions as independent luminescent centers, which display blue phosphorescence and green persistent afterglow with the highest quantum yields of 39.9 % and 57.3 %, respectively. Significantly, the luminescence lifetime can be fine-tuned in the range of 0.0968-0.5046 µs and 33.46-125.61 ms as temporary time coding through precisely controlling the heavy atomic effect and inter-molecular interactions. As a consequence, synchronous blue phosphorescence and green afterglow are integrated into one 0D halide platform with adjustable emission lifetime acting as color- and time-resolved dual RTP materials, which realize the multiple applications in high-level anti-counterfeiting and information storage. The color-lifetime-dual-resolved encoding ability greatly broadens the scope of luminescent halide materials for optical multiplexing applications.

4.
BMC Cancer ; 24(1): 902, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39061024

ABSTRACT

BACKGROUND: TBK1 positively regulates the growth factor-mediated mTOR signaling pathway by phosphorylating mTOR. However, it remains unclear how the TBK1-mTOR signaling pathway is regulated. Considering that STING not only interacts with TBK1 but also with MARCH1, we speculated that MARCH1 might regulate the mTOR signaling pathway by targeting TBK1. The aim of this study was to determine whether MARCH1 regulates the mTOR signaling pathway by targeting TBK1. METHODS: The co-immunoprecipitation (Co-IP) assay was used to verify the interaction between MARCH1 with STING or TBK1. The ubiquitination of STING or TBK1 was analyzed using denatured co-immunoprecipitation. The level of proteins detected in the co-immunoprecipitation or denatured co-immunoprecipitation samples were determined by Western blotting. Stable knocked-down cells were constructed by infecting lentivirus bearing the related shRNA sequences. Scratch wound healing and clonogenic cell survival assays were used to detect the migration and proliferation of breast cancer cells. RESULTS: We showed that MARCH1 played an important role in growth factor-induced the TBK1- mTOR signaling pathway. MARCH1 overexpression attenuated the growth factor-induced activation of mTOR signaling pathway, whereas its deficiency resulted in the opposite effect. Mechanistically, MARCH1 interacted with and promoted the K63-linked ubiquitination of TBK1. This ubiquitination of TBK1 then attenuated its interaction with mTOR, thereby inhibiting the growth factor-induced mTOR signaling pathway. Importantly, faster proliferation induced by MARCH1 deficiency was weakened by mTOR, STING, or TBK1 inhibition. CONCLUSION: MARCH1 suppressed growth factors mediated the mTOR signaling pathway by targeting the STING-TBK1-mTOR axis.


Subject(s)
Cell Proliferation , Protein Serine-Threonine Kinases , Signal Transduction , TOR Serine-Threonine Kinases , Ubiquitin-Protein Ligases , Ubiquitination , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Humans , TOR Serine-Threonine Kinases/metabolism , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , Cell Line, Tumor , Membrane Proteins/metabolism , Membrane Proteins/genetics , Female , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Cell Movement
5.
Nat Commun ; 15(1): 5799, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38987544

ABSTRACT

Germ granules are biomolecular condensates present in most animal germ cells. One function of germ granules is to help maintain germ cell totipotency by organizing mRNA regulatory machinery, including small RNA-based gene regulatory pathways. The C. elegans germ granule is compartmentalized into multiple subcompartments whose biological functions are largely unknown. Here, we identify an uncharted subcompartment of the C. elegans germ granule, which we term the E granule. The E granule is nonrandomly positioned within the germ granule. We identify five proteins that localize to the E granule, including the RNA-dependent RNA polymerase (RdRP) EGO-1, the Dicer-related helicase DRH-3, the Tudor domain-containing protein EKL-1, and two intrinsically disordered proteins, EGC-1 and ELLI-1. Localization of EGO-1 to the E granule enables synthesis of a specialized class of 22G RNAs, which derive exclusively from 5' regions of a subset of germline-expressed mRNAs. Defects in E granule assembly elicit disordered production of endogenous siRNAs, which disturbs fertility and the RNAi response. Our results define a distinct subcompartment of the C. elegans germ granule and suggest that one function of germ granule compartmentalization is to facilitate the localized production of specialized classes of small regulatory RNAs.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Cytoplasmic Granules , Germ Cells , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/genetics , Animals , Germ Cells/metabolism , Cytoplasmic Granules/metabolism , RNA, Messenger/metabolism , RNA, Messenger/genetics , DEAD-box RNA Helicases/metabolism , DEAD-box RNA Helicases/genetics , RNA-Dependent RNA Polymerase/metabolism , RNA-Dependent RNA Polymerase/genetics , Intrinsically Disordered Proteins/metabolism , Intrinsically Disordered Proteins/genetics
6.
Br J Cancer ; 131(3): 430-443, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38877108

ABSTRACT

BACKGROUND: Targeting DNA damage repair factors, such as DNA-dependent protein kinase catalytic subunit (DNA-PKcs), may offer an opportunity for effective treatment of multiple myeloma (MM). In combination with DNA damage-inducing agents, this strategy has been shown to improve chemotherapies partially via activation of cGAS-STING pathway by an elevated level of cytosolic DNA. However, as cGAS is primarily sequestered by chromatin in the nucleus, it remains unclear how cGAS is released from chromatin and translocated into the cytoplasm upon DNA damage, leading to cGAS-STING activation. METHODS: We examined the role of DNA-PKcs inhibition on cGAS-STING-mediated MM chemosensitivity by performing mass spectrometry and mechanism study. RESULTS: Here, we found DNA-PKcs inhibition potentiated DNA damage-inducing agent doxorubicin-induced anti-MM effect by activating cGAS-STING signaling. The cGAS-STING activation in MM cells caused cell death partly via IRF3-NOXA-BAK axis and induced M1 polarization of macrophages. Moreover, this activation was not caused by defective classical non-homologous end joining (c-NHEJ). Instead, upon DNA damage induced by doxorubicin, inhibition of DNA-PKcs promoted cGAS release from cytoplasmic chromatin fragments and increased the amount of cytosolic cGAS and DNA, activating cGAS-STING. CONCLUSIONS: Inhibition of DNA-PKcs could improve the efficacy of doxorubicin in treatment of MM by de-sequestrating cGAS in damaged chromatin.


Subject(s)
Chromatin , DNA Damage , DNA-Activated Protein Kinase , Doxorubicin , Membrane Proteins , Multiple Myeloma , Nucleotidyltransferases , Humans , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Multiple Myeloma/metabolism , Multiple Myeloma/genetics , Nucleotidyltransferases/metabolism , Nucleotidyltransferases/genetics , DNA-Activated Protein Kinase/metabolism , DNA-Activated Protein Kinase/antagonists & inhibitors , Chromatin/metabolism , Chromatin/drug effects , DNA Damage/drug effects , Doxorubicin/pharmacology , Membrane Proteins/metabolism , Membrane Proteins/genetics , Cell Line, Tumor , Mice , Animals , Signal Transduction/drug effects
7.
Food Chem ; 455: 139777, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-38850970

ABSTRACT

In this study, the overall sensory characteristics and low-molecule-weight compounds were analyzed to achieve the discrimination of different commercial salmons and investigate the salmon's sensory and nutritional quality. The results showed that above the overall sensory properties, O. mykiss, S. salar, and O. kisutch were the most satisfied salmons by the panel with the desirable texture and flavor, which displayed a large potential for growth in the consumption market. The alcohols and sulfur compounds were key volatile compounds contributing to typical aroma of O. masou and O. gorbuscha, response higher than others by 147% to 167%. The oligopeptides and phospholipids in salmon could be used as biomarkers for discrimination of these salmon. Oligopeptides were also closely related to the taste quality of salmon. Seventeen oligopeptides showed potential umami activity based on molecular docking results, especially Arg-Val and Ser-Asn, which were the key tastants contributing to the umami of salmon.


Subject(s)
Oligopeptides , Salmon , Seafood , Taste , Animals , Oligopeptides/chemistry , Oligopeptides/analysis , Seafood/analysis , Humans , Molecular Docking Simulation , Molecular Weight , Phospholipids/chemistry , Odorants/analysis , Nutritive Value
8.
Aging (Albany NY) ; 16(11): 9727-9752, 2024 06 05.
Article in English | MEDLINE | ID: mdl-38843383

ABSTRACT

This study explored the role of 14-3-3σ in carbon ion-irradiated pancreatic adenocarcinoma (PAAD) cells and xenografts and clarified the underlying mechanism. The clinical significance of 14-3-3σ in patients with PAAD was explored using publicly available databases. 14-3-3σ was silenced or overexpressed and combined with carbon ions to measure cell proliferation, cell cycle, and DNA damage repair. Immunoblotting and immunofluorescence (IF) assays were used to determine the underlying mechanisms of 14-3-3σ toward carbon ion radioresistance. We used the BALB/c mice to evaluate the biological behavior of 14-3-3σ in combination with carbon ions. Bioinformatic analysis revealed that PAAD expressed higher 14-3-3σ than normal pancreatic tissues; its overexpression was related to invasive clinicopathological features and a worse prognosis. Knockdown or overexpression of 14-3-3σ demonstrated that 14-3-3σ promoted the survival of PAAD cells after carbon ion irradiation. And 14-3-3σ was upregulated in PAAD cells during DNA damage (carbon ion irradiation, DNA damaging agent) and promotes cell recovery. We found that 14-3-3σ resulted in carbon ion radioresistance by promoting RPA2 and RAD51 accumulation in the nucleus in PAAD cells, thereby increasing homologous recombination repair (HRR) efficiency. Blocking the HR pathway consistently reduced 14-3-3σ overexpression-induced carbon ion radioresistance in PAAD cells. The enhanced radiosensitivity of 14-3-3σ depletion on carbon ion irradiation was also demonstrated in vivo. Altogether, 14-3-3σ functions in tumor progression and can be a potential target for developing biomarkers and treatment strategies for PAAD along with incorporating carbon ion irradiation.


Subject(s)
14-3-3 Proteins , Mice, Inbred BALB C , Pancreatic Neoplasms , Recombinational DNA Repair , 14-3-3 Proteins/metabolism , 14-3-3 Proteins/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/radiotherapy , Animals , Humans , Mice , Cell Line, Tumor , Down-Regulation , Radiation Tolerance/genetics , Exoribonucleases/metabolism , Exoribonucleases/genetics , Heavy Ion Radiotherapy , Carbon , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Male , DNA Damage , Female
9.
Front Hum Neurosci ; 18: 1325324, 2024.
Article in English | MEDLINE | ID: mdl-38807633

ABSTRACT

Background: Parkinson's disease (PD) generally progresses slowly, but it is controversial whether delaying treatment accelerates the progression. Objective: Determine the correlation between the time of dopaminergic replacement treatment initiation and the severity of clinical symptoms in PD, including motor and non-motor symptoms. Methods: PD patients were divided between 155 people who were diagnosed de novo and 165 PD patients receiving dopamine replacement therapy. Basic patient characteristics included gender, age, age at onset, disease duration, and the time of dopaminergic replacement treatment initiation. We used MDS-UPDRS scores to evaluate the severity of motor symptoms and we also used the scale to assess the severity of non-motor symptoms such as cognition, mood, sleep, and quality of life. Results: The mean time between symptom onset and the initiation of drug treatment was 31.0 (22.5) months. After adjusting for age, sex, age at onset, and disease duration, we found that the MDS-Unified Parkinson's Disease Rating Scale (UPDRS)-III score increased faster in the de novo group with a similar disease duration (F = 8.7, p = 0.0034) than the treatment group. The cumulative incidence of progression to H-Y score 3 in de novo PD group over disease duration was 39.7% in 50months and 92.2% in 100 months, while in treated group such cumulative incidence was 15.5% in 50 months, 51.4% in 100 months and 81.5% in 150 months. The cumulative incidence of patients in the de novo PD group was higher than that in the treated group (p = 0.001), suggesting that untreated patients were more likely to progress to the advanced stages. Symptoms onset, the time between symptom onset and treatment initiation, age, sex, and disease duration explained 28.95% of the total variation in the MDS-UPDRS-III score for motor symptoms. In drug-naïve patients, the time between symptom onset and treatment initiation explained 20.1% of the total variation in the MDS-UPDRS-III score for motor symptoms (t = 6.15, p < 0.001). Conclusions: These data in our study showed that early dopaminergic replacement treatment have played a positive role in PD patients, while dopaminergic replacement delayed treatment might be detrimental to motor symptoms and non-motor state of PD patient. Recognizing early stage symptoms of PD and early diagnosis are of great significance to treatment.

10.
J Lipid Res ; 65(6): 100553, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38704027

ABSTRACT

Multiple isozymes are encoded in the Caenorhabditis elegans genome for the various sphingolipid biosynthesis reactions, but the contributions of individual isozymes are characterized only in part. We developed a simple but effective reversed-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) method that enables simultaneous identification and quantification of ceramides (Cer), glucosylceramides (GlcCer), and sphingomyelins (SM) from the same MS run. Validating this sphingolipid profiling method, we show that nearly all 47 quantifiable sphingolipid species found in young adult worms were reduced upon RNA interference (RNAi) of sptl-1 or elo-5, which are both required for synthesis of the id17:1 sphingoid base. We also confirm that HYL-1 and HYL-2, but not LAGR-1, constitute the major ceramide synthase activity with different preference for fatty acid substrates, and that CGT-3, but not CGT-1 and CGT-2, plays a major role in producing GlcCers. Deletion of sms-5 hardly affected SM levels. RNAi of sms-1, sms-2, and sms-3 all lowered the abundance of certain SMs with an odd-numbered N-acyl chains (mostly C21 and C23, with or without hydroxylation). Unexpectedly, sms-2 RNAi and sms-3 RNAi elevated a subset of SM species containing even-numbered N-acyls. This suggests that sphingolipids containing even-numbered N-acyls could be regulated separately, sometimes in opposite directions, from those containing odd-numbered N-acyls, which are presumably monomethyl branched chain fatty acyls. We also find that ceramide levels are kept in balance with those of GlcCers and SMs. These findings underscore the effectiveness of this RPLC-MS/MS method in studies of C. elegans sphingolipid biology.


Subject(s)
Caenorhabditis elegans , Isoenzymes , Sphingolipids , Animals , Caenorhabditis elegans/metabolism , Caenorhabditis elegans/genetics , Caenorhabditis elegans/enzymology , Sphingolipids/biosynthesis , Sphingolipids/metabolism , Isoenzymes/metabolism , Isoenzymes/genetics , Tandem Mass Spectrometry , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/genetics , Ceramides/metabolism , Ceramides/biosynthesis , RNA Interference , Chromatography, Liquid
11.
Nature ; 630(8016): 484-492, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38811729

ABSTRACT

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Subject(s)
Bacteria , Bacteriophages , CRISPR-Associated Protein 9 , CRISPR-Cas Systems , Bacteria/virology , Bacteria/genetics , Bacteria/immunology , Bacteriophages/genetics , Bacteriophages/immunology , Chryseobacterium/genetics , Chryseobacterium/immunology , Chryseobacterium/virology , CRISPR-Associated Protein 9/chemistry , CRISPR-Associated Protein 9/genetics , CRISPR-Associated Protein 9/metabolism , CRISPR-Cas Systems/genetics , CRISPR-Cas Systems/immunology , DNA Cleavage , Genetic Loci/genetics , Models, Molecular , Protein Domains
12.
Front Biosci (Landmark Ed) ; 29(4): 144, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38682183

ABSTRACT

BACKGROUND: Gliomas are characterized by aggressive behavior, leading to severe disability and high mortality. Ubiquitin-like modifier activating enzyme 2 (UBA2) is a subunit of the E1-activating enzyme involved in the SUMOylation (SUMO, small ubiquitin-related modifier) of numerous proteins. Although the abnormality of UBA2 is linked to the progression of various tumor types, the role of UBA2 in glioma is still unknown. METHODS: A bioinformatic analysis using several public databases was conducted to examine the expression level, clinicopathological correlations, and prognostic significance of UBA2 in glioma. The correlation between UBA2 expression and drug sensitivity in cancers was also explored. Multiple cellular experiments were conducted to validate the role of UBA2 in glioma. RESULTS: Analysis of multiple databases and cellular experiments revealed that UBA2 was overexpressed in glioma tissues and cell lines, respectively. UBA2 expression in gliomas correlated with World Health Organization (WHO) grade, IDH gene status, 1p19q deletion, histological type, and immune cell infiltration in glioma. UBA2 expression in carcinomas also correlated with drug sensitivity. Kaplan-Meier analysis revealed that high expression of UBA2 predicted poorer survival in glioma patients. A nomogram model containing UBA2 expression was constructed for clinical practice. Knockdown of UBA2 was observed to suppress glioma cell progression and sensitize glioma cells to irradiation in vitro. CONCLUSION: Overall, this research showed that UBA2 might be involved not only in the development of glioma but also in the regulation of immunity, drug sensitivity, and radiosensitivity. Therefore, UBA2 may be a potential target for therapy and a candidate biomarker for glioma diagnosis and prognosis.


Subject(s)
Biomarkers, Tumor , Glioma , Ubiquitin-Activating Enzymes , Glioma/diagnosis , Glioma/immunology , Glioma/mortality , Glioma/therapy , Cell Line, Tumor , Prognosis , Ubiquitin-Activating Enzymes/analysis , Ubiquitin-Activating Enzymes/metabolism , Immunotherapy , Radiation Tolerance , Disease Progression
13.
Oncogene ; 43(23): 1769-1778, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38632437

ABSTRACT

Pyruvate kinase M2 (PKM2) is a central metabolic enzyme driving the Warburg effect in tumor growth. Previous investigations have demonstrated that PKM2 is subject to O-linked ß-N-acetylglucosamine (O-GlcNAc) modification, which is a nutrient-sensitive post-translational modification. Here we found that unc-51 like autophagy activating kinase 1 (ULK1), a glucose-sensitive kinase, interacts with PKM2 and phosphorylates PKM2 at Ser333. Ser333 phosphorylation antagonizes PKM2 O-GlcNAcylation, promotes its tetramer formation and enzymatic activity, and decreases its nuclear localization. As PKM2 is known to have a nuclear role in regulating c-Myc, we also show that PKM2-S333 phosphorylation inhibits c-Myc expression. By downregulating glucose consumption and lactate production, PKM2 pS333 attenuates the Warburg effect. Through mouse xenograft assays, we demonstrate that the phospho-deficient PKM2-S333A mutant promotes tumor growth in vivo. In conclusion, we identified a ULK1-PKM2-c-Myc axis in inhibiting breast cancer, and a glucose-sensitive phosphorylation of PKM2 in modulating the Warburg effect.


Subject(s)
Autophagy-Related Protein-1 Homolog , Breast Neoplasms , Carrier Proteins , Intracellular Signaling Peptides and Proteins , Membrane Proteins , Thyroid Hormone-Binding Proteins , Thyroid Hormones , Warburg Effect, Oncologic , Humans , Autophagy-Related Protein-1 Homolog/metabolism , Autophagy-Related Protein-1 Homolog/genetics , Phosphorylation , Animals , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Female , Mice , Thyroid Hormones/metabolism , Thyroid Hormones/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics , Carrier Proteins/metabolism , Carrier Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Cell Line, Tumor , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Acetylglucosamine/metabolism
14.
Biochem Biophys Res Commun ; 710: 149918, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38598902

ABSTRACT

Chimeric antigen receptor (CAR)-modified immune cells have emerged as a promising approach for cancer treatment, but single-target CAR therapy in solid tumors is limited by immune escape caused by tumor antigen heterogeneity and shedding. Natural killer group 2D (NKG2D) is an activating receptor expressed in human NK cells, and its ligands, such as MICA and MICB (MICA/B), are widely expressed in malignant cells and typically absent from healthy tissue. NKG2D plays an important role in anti-tumor immunity, recognizing tumor cells and initiating an anti-tumor response. Therefore, NKG2D-based CAR is a promising CAR candidate. Nevertheless, the shedding of MICA/B hinders the therapeutic efficacy of NKG2D-CARs. Here, we designed a novel CAR by engineering an anti-MICA/B shedding antibody 1D5 into the CAR construct. The engineered NK cells exhibited significantly enhanced cytotoxicity against various MICA/B-expressing tumor cells and were not inhibited by NKG2D antibody or NKG2D-Fc fusion protein, indicating no interference with NKG2D-MICA/B binding. Therefore, the developed 1D5-CAR could be combined with NKG2D-CAR to further improve the obstacles caused by MICA/B shedding.


Subject(s)
Neoplasms , Receptors, Chimeric Antigen , Humans , Cell Line, Tumor , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class I/metabolism , Killer Cells, Natural , Neoplasms/immunology , Neoplasms/metabolism , NK Cell Lectin-Like Receptor Subfamily K/genetics , NK Cell Lectin-Like Receptor Subfamily K/metabolism , Receptors, Chimeric Antigen/genetics , Receptors, Chimeric Antigen/metabolism , Immunotherapy, Adoptive/methods
15.
Cell Death Dis ; 15(4): 290, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38658567

ABSTRACT

High-grade serous ovarian cancer (HGSOC) represents the most common and lethal subtype of ovarian cancer. Despite initial response to platinum-based standard therapy, patients commonly suffer from relapse that likely originates from drug-tolerant persister (DTP) cells. We generated isogenic clones of treatment-naïve and cisplatin-tolerant persister HGSOC cells. In addition, single-cell RNA sequencing of barcoded cells was performed in a xenograft model with HGSOC cell lines after platinum-based therapy. Published single-cell RNA-sequencing data from neo-adjuvant and non-treated HGSOC patients and patient data from TCGA were analyzed. DTP-derived cells exhibited morphological alterations and upregulation of epithelial-mesenchymal transition (EMT) markers. An aggressive subpopulation of DTP-derived cells showed high expression of the stress marker ATF3. Knockdown of ATF3 enhanced the sensitivity of aggressive DTP-derived cells to cisplatin-induced cell death, implying a role for ATF3 stress response in promoting a drug tolerant persister cell state. Furthermore, single cell lineage tracing to detect transcriptional changes in a HGSOC cell line-derived xenograft relapse model showed that cells derived from relapsed solid tumors express increased levels of EMT and multiple endoplasmic reticulum (ER) stress markers, including ATF3. Single cell RNA sequencing of epithelial cells from four HGSOC patients also identified a small cell population resembling DTP cells in all samples. Moreover, analysis of TCGA data from 259 HGSOC patients revealed a significant progression-free survival advantage for patients with low expression of the ATF3-associated partial EMT genes. These findings suggest that increased ATF3 expression together with partial EMT promote the development of aggressive DTP, and thereby relapse in HGSOC patients.


Subject(s)
Activating Transcription Factor 3 , Cisplatin , Drug Resistance, Neoplasm , Epithelial-Mesenchymal Transition , Ovarian Neoplasms , Humans , Activating Transcription Factor 3/metabolism , Activating Transcription Factor 3/genetics , Female , Cisplatin/pharmacology , Cisplatin/therapeutic use , Cell Line, Tumor , Drug Resistance, Neoplasm/genetics , Drug Resistance, Neoplasm/drug effects , Epithelial-Mesenchymal Transition/drug effects , Epithelial-Mesenchymal Transition/genetics , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Ovarian Neoplasms/metabolism , Animals , Mice , Xenograft Model Antitumor Assays , Gene Expression Regulation, Neoplastic/drug effects
16.
Nanotechnology ; 35(27)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38574465

ABSTRACT

The morphology and size control of anisotropic nanocrystals are critical for tuning shape-dependent physicochemical properties. Although the anisotropic dissolution process is considered to be an effective means to precisely control the size and morphology of nanocrystals, the anisotropic dissolution mechanism remains poorly understood. Here, usingin situliquid cell transmission electron microscopy, we investigate the anisotropic etching dissolution behaviors of polyvinylpyrrolidone (PVP)-stabilized Ag nanorods in NaCl solution. Results show that etching dissolution occurs only in the longitudinal direction of the nanorod at low chloride concentration (0.2 mM), whereas at high chloride concentration (1 M), the lateral and longitudinal directions of the nanorods are dissolved. First-principles calculations demonstrate that PVP is selectively adsorbed on the {100} crystal plane of silver nanorods, making the tips of nanorods the only reaction sites in the anisotropic etching process. When the chemical potential difference of the Cl-concentration is higher than the diffusion barrier (0.196 eV) of Cl-in the PVP molecule, Cl-penetrates the PVP molecular layer of {100} facets on the side of the Ag nanorods. These findings provide an in-depth insight into the anisotropic etching mechanisms and lay foundations for the controlled preparation and rational design of nanostructures.

17.
Materials (Basel) ; 17(6)2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38541388

ABSTRACT

Currently, 1060 aluminum alloy is widely applied in the electronics industry, construction, the aerospace field, traffic engineering, decorations, and the consumer goods market for its good chemical, physical, and mechanical properties. In general, excellent processing property is necessary and important for the manufacturing of complicated panels. In this paper, a special 2D ultrasonic vibration incremental forming method is designed to improve its plasticity and mechanical properties. Three kind of processing methods, including traditional single-point incremental forming, longitudinal ultrasonic vibration incremental forming, and 2D ultrasonic vibration incremental forming, are used for the flexible manufacturing of cones and cylindrical cups of 1060 aluminum alloy sheet. Then, micro-hardness tests, residual stress tests, and scanning electron microscopy tests are carried out to probe the changes in micro-structure and mechanical properties and to analyze the effects of different types of ultrasonic vibration on the plasticity and fracture characteristic of 1060 aluminum alloy. It is proven that 2D ultrasonic vibration facilitates the improvement of plasticity and surface qualities of 1060 aluminum alloy better than the other two processing methods. Therefore, the novel 2D ultrasonic vibration incremental forming process possesses substantial application value for the flexible and rapid manufacturing of complicated thin-walled component of aluminum alloy.

18.
J Cancer ; 15(8): 2245-2259, 2024.
Article in English | MEDLINE | ID: mdl-38495488

ABSTRACT

Background and goal: Carbon ion beam is radio-biologically more efficient than photons and is beneficial for treating radio-resistant tumors. Several animal experiments with tumor-bearing suggest that carbon ion beam irradiation in combination with immunotherapy yields better results, especially in controlling distant metastases. This implies that carbon ion induces a different anti-tumor immune response than photon beam. More complex molecular mechanisms need to be uncovered. This in vivo and in vitro experiment was carried out in order to examine the radio-immune effects and the mechanism of action of carbon ion beam versus X-ray in combination with PD-1 inhibitors. Methods and Materials: Lewis lung adenocarcinoma cells and C57BL/6 mice were used to create a tumor-bearing mouse model, with the non-irradiated tumor growing on the right hind leg and the irradiated tumor on the left rear. 10Gy carbon ion beam or X-ray radiation, either alone or in combination with PD-1 inhibitor, were used to treat the left back tumor. The expression of molecules linked to immunogenicity and the infiltration of CD8+ T lymphocytes into tumor tissues were both identified using immunohistochemistry. IFN-ß in mouse serum was measured using an ELISA, while CD8+ T cells in mouse peripheral blood were measured using flow cytometry. Lewis cells were exposed to different dose of X-ray and carbon ion. TREX1, PD-L1, and IFN-ß alterations in mRNA and protein levels were identified using Western blot or RT-PCR, respectively. TREX1 knockdown was created by siRNA transfection and exposed to various radiations. Using the CCK8 test, EdU assay, and flow cytometry, changes in cell viability, proliferation, and apoptosis rate were discovered. Results: Bilateral tumors were significantly inhibited by the use of carbon ion or X-ray in combination with PD-1, particularly to non-irradiated tumor(p<0.05). The percentage of infiltrating CD8+ T cells and the level of IFN-ß expression were both raised by 10Gy carbon ion irradiation in the irradiated side tumor, although PD-L1 and TREX1 expression levels were also elevated. Lewis cell in vitro experiment further demonstrated that both X-ray and carbon ion irradiation can up-regulate the expression levels of PD-L1 and TREX1 with dose-dependent in tumors, particularly the trend of up-regulation TREX1 is more apparent at a higher dose in carbon ion, i.e. 8 or 10Gy, while the level of IFN-ß is decreased. IFN-ß levels were considerably raised under hypofractionated doses of carbon ion radiation by gene silencing TREX1. Conclusions: By enhancing tumor immunogenicity and increasing CD8+T infiltration in TME through a threshold dosage, X-ray or carbon ion radiation and PD-1 inhibitors improve anti-tumor activity and cause abscopal effect in Lewis lung adenocarcinoma-bearing mice. TREX1 is a possible therapeutic target and prognostic marker.

19.
Cell Metab ; 36(3): 459-460, 2024 03 05.
Article in English | MEDLINE | ID: mdl-38447527

ABSTRACT

It is generally believed that the contributions of the UCP1-independent thermogenic pathways are secondary to UCP1-mediated thermogenesis in BAT. Now, Rahbani et al. demonstrate in vivo that adaptive thermogenesis in brown adipose tissue is regulated by UCP1 and CKB in parallel.


Subject(s)
Adipose Tissue, Brown , Thermogenesis
20.
Front Cell Infect Microbiol ; 14: 1363437, 2024.
Article in English | MEDLINE | ID: mdl-38529473

ABSTRACT

Purpose: The objective of this study was to investigate the epidemiological characteristics, distribution of isolates, prevailing patterns, and antibiotic susceptibility of bacterial keratitis (BK) in a Tertiary Referral Hospital located in Southwest China. Methods: A retrospective analysis was conducted on 660 cases of bacterial keratitis occurring between January 2015 and December 2022. The demographic data, predisposing factors, microbial findings, and antibiotic sensitivity profiles were examined. Results: Corneal trauma emerged as the most prevalent predisposing factor, accounting for 37.1% of cases. Among these cases, bacterial culture results were positive in 318 cases, 68 species of bacteria were identified. The most common Gram-Positive bacteria isolated overall was the staphylococcus epidermis and the most common Gram-Negative bacteria isolated was Pseudomonas aeruginosa. Methicillin-Resistant Staphylococci accounted for 18.1% of all Gram-Positive bacteria. The detection rate of P. aeruginosa showed an increasing trend over time (Rs=0.738, P=0.037). There was a significant decrease in the percentage of Gram-Negative microorganisms over time (Rs=0.743, P=0.035). The sensitivity of Gram-Positive bacteria to linezolid, vancomycin, tigecycline, quinupristin/dalfopristin, and rifampicin was over 98%. The sensitivity rates of Gram-Negative bacteria to amikacin, meropenem, piperacillin/tazobactam, cefoperazone sodium/sulbactam, ceftazidime, and cefepime were all above 85%. In patients with a history of vegetative trauma, the possibility of BK should be taken into account in addition to the focus on fungal keratitis. Conclusion: The microbial composition primarily consists of Gram-Positive cocci and Gram-Negative bacilli. Among the Gram-Positive bacteria, S. epidermidis and Streptococcus pneumoniae are the most frequently encountered, while P. aeruginosa is the predominant Gram-Negative bacteria. To combat Gram-Positive bacteria, vancomycin, linezolid, and rifampicin are considered excellent antimicrobial agents. When targeting Gram-Negative pathogens, third-generation cephalosporins exhibit superior sensitivity compared to first and second-generation counterparts. As an initial empirical treatment for severe cases of bacterial keratitis and those unresponsive to fourth-generation fluoroquinolones in community settings, the combination therapy of vancomycin and tobramycin is a justifiable approach. Bacterial keratitis can be better managed by understanding the local etiology and antibacterial drug susceptibility patterns.


Subject(s)
Eye Infections, Bacterial , Keratitis , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Linezolid/therapeutic use , Vancomycin , Rifampin , Retrospective Studies , Tertiary Care Centers , Drug Resistance, Bacterial , Cefoperazone/therapeutic use , Eye Infections, Bacterial/drug therapy , Eye Infections, Bacterial/epidemiology , Sulbactam/therapeutic use , Gram-Positive Bacteria , Staphylococcus , Gram-Negative Bacteria , Keratitis/drug therapy , Keratitis/epidemiology , Keratitis/microbiology , Microbial Sensitivity Tests
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