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1.
Artigo em Inglês | MEDLINE | ID: mdl-39341699

RESUMO

BACKGROUND: Whether HCV infection is associated with colorectal cancer (CRC) development remains inconclusive. METHODS: A nationwide population-based cohort study of the Taiwan National Health Insurance Research Database was conducted. RESULTS: From 2003 to 2012, 1:2:2 propensity score-matched HCV-treated [interferon-based therapy ≥ 6 months, surveys for CRC (n = 9017), colon cancer (CC) (n = 9,022) and rectal cancer (RC) (n = 9,033), HCV-untreated and HCV-uninfected cohorts CRC (n = 18034), CC (n = 18,044) and RC (n = 18,066) were enrolled. The HCV-uninfected cohort had the lowest cumulative incidence of CRC (0.117%; 95% CI: 0.062%-0.207%), whereas the HCV-treated (0.966%; 0.375-2.122%) and HCV-untreated (0.807%; 0.485%-1.280%) cohorts had similar incidences (P = .0662); HCV infection [reference: HCV-untreated cohort, HCV-treated: hazard ratio (HR): 0.598; 95% CI HR: 0.337-1.059; HCV-uninfected: 0.250; 0.138-0.456] and age ≥ 49 years (3.128;1.751-5.59) were associated with CRC development. The HCV-untreated cohort had the highest cumulative incidence of CC (0.883%; 0.371-1.839%), while HCV-treated (0.478%; 0.110-1.518%) and HCV-uninfected cohorts (0.147%; 0.071-0.284%) had similar incidences (P = .4853); HCV infection (HCV-treated: 0.474; 0.232-0.971; HCV-uninfected: 0.338; 0.184-0.62), male sex (2.18; 1.301-3.654), age≥ 49 years (4.818; 2.123-10.936) and diabetes (1.983; 1.205-3.262) were associated with CC development. A higher RC cumulative incidence was noted in the HCV-untreated cohort (0.332%; 0.151-0.664%) than in the HCV-uninfected cohort (0.116%; 0.054-0.232%) (P = .0352); HCV infection (HCV-treated: 0.691; 0.295-1.617; HCV-uninfected: 0.424; 0.207-0.867), age ≥ 49 years (3.745, 1.576-8.898) and stroke (3.162; 1.366-7.322) were associated with RC development. CONCLUSIONS: The baseline associations were HCV infection and age ≥ 49 years with CRC; male sex and diabetes with CC; and stroke with RC. Anti-HCV therapy might reverse the risk of HCV-related CC but not RC.

2.
bioRxiv ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39229073

RESUMO

Reduced responsiveness of precursor B-acute lymphoblastic leukemia (BCP-ALL) to chemotherapy can be first detected in the form of minimal residual disease leukemia cells that persist after 28 days of initial treatment. The ability of these cells to resist chemotherapy is partly due to the microenvironment of the bone marrow, which promotes leukemia cell growth and provides protection, particularly under these conditions of stress. It is unknown if and how the glycocalyx of such cells is remodelled during the development of tolerance to drug treatment, even though glycosylation is the most abundant cell surface post-translational modification present on the plasma membrane. To investigate this, we performed omics analysis of BCP-ALL cells that survived a 30-day vincristine chemotherapy treatment while in co-culture with bone marrow stromal cells. Proteomics showed decreased levels of some metabolic enzymes. Overall glycocalyx changes included a shift from Core-2 to less complex Core-1 O-glycans, and reduced overall sialylation, with a shift from α2-6 to α2-3 linked Neu5Ac. Interestingly, there was a clear increase in bisecting complex N-glycans with a concomitant increased mRNA expression of MGAT3 , the only enzyme known to form bisecting N-glycans. These small but reproducible quantitative differences suggest that individual glycoproteins become differentially glycosylated. Glycoproteomics confirmed glycosite-specific modulation of cell surface and lysosomal proteins in drug-tolerant BCP-ALL cells, including HLA-DRA, CD38, LAMP1 and PPT1. We conclude that drug-tolerant persister leukemia cells that grow under continuous chemotherapy stress have characteristic glycotraits that correlate with and perhaps contribute to their ability to survive and could be tested as neoantigens in drug-resistant leukemia.

3.
Nat Commun ; 15(1): 7038, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147846

RESUMO

Soft-matter-based photonic crystals like blue-phase liquid crystals (BPLC) have potential applications in wide-ranging photonic and bio-chemical systems. To date, however, there are limitations in the fabrication of large monocrystalline BPLCs. Traditional crystal-growth process involves the transition from a high-temperature disordered phase to an ordered (blue) phase and is generally slow (takes hours) with limited achievable lattice structures, and efforts to improve molecular alignment through post-crystallization field application typically prove ineffective. Here we report a systematic study on the molecular self-assembly dynamics of BPLC starting from a highly ordered phase in which all molecules are unidirectionally aligned by a strong electric field. We have discovered that, near the high-temperature end of the blue phase, if the applied field strength is then switched to an intermediate level or simply turned off, large-area monocrystalline BPLCs of various symmetries (tetragonal, orthorhombic, cubic) can be formed in minutes. Subsequent temperature tuning of the single crystal at a fixed applied field allows access to different lattice parameters and the formation of never-before-seen monoclinic structures. The formed crystals remain stable upon field removal. The diversity of stable monocrystalline BPLCs with widely tunable crystalline symmetries, band structures, and optical dispersions will significantly improve and expand their application potentials.

4.
Opt Lett ; 49(16): 4501-4504, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146088

RESUMO

Recent progress in the fabrication of Yb-doped silicate fibers with low concentration quenching and low background absorption loss has led to the demonstration of anti-Stokes-fluorescence cooling in several aluminosilicate compositions. This breakthrough is critical to combat deleterious thermal effects due to the quantum defect in fiber lasers and amplifiers. Since cooling efficiencies remain low (1-2.7%), it is paramount to engineer compositions that improve this metric. We report a silica fiber with a core glass heavily doped with aluminum and phosphorus that sets, to our knowledge, a few new records. This few-mode fiber (16-µm core) was cooled in air by -0.25 K from room temperature with ∼0.5 W of 1040-nm power. The measured cooling efficiency is 3.3% at low pump power and 2.8% at the power that produced maximum cooling. The critical quenching concentration inferred from the measured dependence of cooling on pump power and careful calibration of the pump absorption and saturation is 79 wt.%. The inferred background absorption loss is 15 dB/km. Together with the fiber's average Yb concentration of 4.2 wt.%, these metrics rank among the best reported in a silica glass.

5.
ACS Nano ; 18(35): 24173-24181, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39167162

RESUMO

Transition metal dichalcogenides (TMDCs) are at the forefront of nanophotonics because of their exceptional optical characteristics. The 2D architecture of TMDCs facilitates efficient light absorption and emission, holding tantalizing potential for next-generation nanophotonic and quantum devices. Yet, the atomic thinness limits their interaction volume with light, affecting light-matter interaction and quantum efficiency. The light coupling in the 2D layered TMDCs can be enhanced by integration with photonic structure, and the metasurfaces supporting bound states in the continuum (BICs) offer strong confinement of optical fields, ideal for coupling with 2D TMDCs. Here, we demonstrate enhanced light-matter coupling by integrating TMDC monolayers, including WSe2 and MoS2, with a finite-area membrane metasurface, leading to amplified and high-quality-factor (Q-factor) spontaneous emission from quasi-BIC-coupled TMDC monolayers. The high-Q-factor emission extends over an area with a scale of a few micrometers while maintaining the high-Q factor across the emission area. Notably, the suspended finite-area membrane metasurface, which is freestanding in air rather than positioned atop a substrate, minimizes radiation loss while enhancing light-matter interaction in the TMDC monolayer. Furthermore, the predominantly in-plane dipole orientation of excitons within TMDC monolayers results in distinctive enhancement behaviors for emission, contingent on the excitation power, when coupled with quasi-BIC modes exhibiting TE and TM resonances. This work introduces a nanophotonic platform for robust coupling of membrane metasurfaces with 2D materials, offering possibilities for developing 2D material-based nanophotonic and quantum devices.

6.
Nano Lett ; 24(35): 11012-11019, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39186248

RESUMO

Ferroelectric catalysts are known for altering surface catalytic activities by changing the direction of their electric polarizations. This study demonstrates polarization-switchable electrochemistry using layered bismuth oxyselenide (L-Bi2O2Se) bifunctional microreactors through ferroelectric modulation. A selective-area ionic liquid gating is developed with precise control over the spatial distribution of the dipole orientation of L-Bi2O2Se. On-chip microreactors with upward polarization favor the oxygen evolution reaction, whereas those with downward polarization prefer the hydrogen evolution reaction. The microscopic origin behind polarization-switchable electrochemistry primarily stems from enhanced surface adsorption and reduced energy barriers for reactions, as examined by nanoscale scanning electrochemical cell microscopy. Integrating a pair of L-Bi2O2Se microreactors consisting of upward or downward polarizations demonstrates overall water splitting in a full-cell configuration based on a bifunctional catalyst. The ability to modulate surface polarizations on a single catalyst via ferroelectric polarization switching offers a pathway for designing catalysts for water splitting.

7.
Small ; 20(36): e2403915, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38973115

RESUMO

In 2D materials, a key engineering challenge is the mass production of large-area thin films without sacrificing their uniform 2D nature and unique properties. Here, it is demonstrated that a simple fluid phenomenon of water/alcohol solvents can become a sophisticated tool for self-assembly and designing organized structures of 2D nanosheets on a water surface. In situ, surface characterizations show that water/alcohol droplets of 2D nanosheets with cationic surfactants exhibit spontaneous spreading of large uniform monolayers within 10 s. Facile transfer of the monolayers onto solid or flexible substrates results in high-quality mono- and multilayer films with high coverages (>95%) and homogeneous electronic/optical properties. This spontaneous spreading is quite general and can be applied to various 2D nanosheets, including metal oxides, graphene oxide, h-BN, MoS2, and transition metal carbides, enabling on-demand smart manufacture of large-size (>4 inchϕ) 2D nanofilms and free-standing membranes.

8.
Rev Clin Esp (Barc) ; 224(8): 503-509, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38972634

RESUMO

PURPOSE: Estimated pulse wave velocity (ePWV) and body mass index (BMI) are significant predictors of new-onset diabetes. This study aims to evaluate the impact and predictive value of combining ePWV and BMI on the incidence of new-onset diabetes. METHODS: A secondary analysis was conducted on a cohort study by Rich Healthcare (China), involving 211,833 eligible participants. Logistic regression analysis identified factors influencing diabetes occurrence, while ROC curve analysis assessed the predictive value of ePWV, BMI, and their combination for new-onset diabetes. RESULTS: Over a mean follow-up period of 3.12 years, 3,000 men (1.41%) and 1,174 women (0.55%) were diagnosed with diabetes. Logistic regression revealed that BMI, triglycerides, alanine aminotransferase, blood urea nitrogen, creatinine clearance rate, ePWV, and family history of diabetes are high-risk factors for new-onset diabetes. The combination of ePWV and BMI provided a higher area under the ROC curve (0.822) compared to ePWV or BMI alone. CONCLUSION: Elevated levels of ePWV and BMI are independent risk factors for new-onset diabetes. Combining these measures enhances predictive accuracy compared to using either indicator alone.


Assuntos
Índice de Massa Corporal , Valor Preditivo dos Testes , Análise de Onda de Pulso , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Adulto , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/fisiopatologia , Fatores de Risco , Idoso , China/epidemiologia , Incidência , Curva ROC , Modelos Logísticos , Estudos de Coortes
9.
J Am Chem Soc ; 146(33): 23278-23288, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39049154

RESUMO

Manipulating electronic polarizations such as ferroelectric or spin polarizations has recently emerged as an effective strategy for enhancing the efficiency of photocatalytic reactions. This study demonstrates the control of electronic polarizations modulated by ferroelectric and magnetic approaches within a two-dimensional (2D) layered crystal of copper indium thiophosphate (CuInP2S6) to boost the photocatalytic reduction of CO2. We investigate the substantial influence of ferroelectric polarization on the photocatalytic CO2 reduction efficiency, utilizing the ferroelectric-paraelectric phase transition and polarization alignment through electrical poling. Additionally, we explore enhancing the CO2 reduction efficiency by harnessing spin electrons through the synergistic introduction of sulfur vacancies and applying a magnetic field. Several advanced characterization techniques, including piezoresponse force microscopy, ultrafast pump-probe spectroscopy, in situ X-ray absorption spectroscopy, and in situ diffuse reflectance infrared Fourier transformed spectroscopy, are performed to unveil the underlying mechanism of the enhanced photocatalytic CO2 reduction. These findings pave the way for manipulating electronic polarizations regulated through ferroelectric or magnetic modulations in 2D layered materials to advance the efficiency of photocatalytic CO2 reduction.

10.
J Cancer Res Clin Oncol ; 150(7): 354, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031214

RESUMO

BACKGROUND: Patients with autoimmune diseases (AD) generally carry an increased risk of developing cancer. However, the effect of AD in hepatocellular carcinoma (HCC) patients receiving surgical treatment is uncertain. The present study aimed to investigate the potential influence of AD on the survival of HCC patients undergoing hepatectomies. METHODS: Operated HCC patients were identified from the Chang Gung Research Database, and the survival outcomes of HCC patients with or without AD were analyzed ad compared. Cox regression model was performed to identify significant risk factors associated with disease recurrence and mortality. RESULTS: From 2002 to 2018, a total of 5532 patients underwent hepatectomy for their HCC. Among them, 229 patients were identified to have AD and 5303 were not. After excluding cases who died within 30 days of surgery, the estimated median overall survival (OS) was 43.8 months in the AD (+) group and 47.4 months in the AD (-) group (P = 0.367). The median liver-specific survival and disease-free survival (DFS) were also comparable between the two groups. After Cox regression multivariate analysis, the presence of AD did not lead to a higher risk of all-cause mortality, liver-specific mortality, or disease recurrence. CONCLUSION: Our study demonstrated that autoimmune disease does not impair the OS and DFS of HCC patients undergoing liver resections. AD itself is not a risk factor for tumor recurrence after surgery. Patients eligible for liver resections, as a result, should be considered for surgery irrespective of the presence of AD. Further studies are mandatory to validate our findings.


Assuntos
Doenças Autoimunes , Carcinoma Hepatocelular , Hepatectomia , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Masculino , Feminino , Hepatectomia/mortalidade , Doenças Autoimunes/complicações , Doenças Autoimunes/mortalidade , Doenças Autoimunes/cirurgia , Pessoa de Meia-Idade , Idoso , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos , Fatores de Risco , Adulto , Taxa de Sobrevida , Prognóstico
12.
Elife ; 122024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38896450

RESUMO

The DNA damage response is critical for maintaining genome integrity and is commonly disrupted in the development of cancer. PPM1D (protein phosphatase Mg2+/Mn2+-dependent 1D) is a master negative regulator of the response; gain-of-function mutations and amplifications of PPM1D are found across several human cancers making it a relevant pharmacological target. Here, we used CRISPR/Cas9 screening to identify synthetic-lethal dependencies of PPM1D, uncovering superoxide dismutase-1 (SOD1) as a potential target for PPM1D-mutant cells. We revealed a dysregulated redox landscape characterized by elevated levels of reactive oxygen species and a compromised response to oxidative stress in PPM1D-mutant cells. Altogether, our results demonstrate a role for SOD1 in the survival of PPM1D-mutant leukemia cells and highlight a new potential therapeutic strategy against PPM1D-mutant cancers.


Assuntos
Proteína Fosfatase 2C , Superóxido Dismutase-1 , Proteína Fosfatase 2C/metabolismo , Proteína Fosfatase 2C/genética , Humanos , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Linhagem Celular Tumoral , Leucemia/genética , Sistemas CRISPR-Cas , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Mutações Sintéticas Letais , Mutação
13.
Int J Mol Sci ; 25(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38928347

RESUMO

Colorectal cancer (CRC) is a global health concern, necessitating adjuvant chemotherapy post-curative surgery to mitigate recurrence and enhance survival, particularly in intermediate-stage patients. However, existing therapeutic disparities highlight the need for biomarker-guided adjuvant chemotherapy to achieve better CRC inhibition. This study explores the molecular mechanisms underlying the inhibition of CRC through a genome-wide association study (GWAS) focused on 5-fluorouracil (5-FU)-based adjuvant therapy in intermediate-stage CRC patients, a domain previously unexplored. We retrospectively included 226 intermediate-stage CRC patients undergoing surgical resection followed by 5-FU-based adjuvant chemotherapy. The exploration cohort comprised 31 patients, and the validation cohort included 195 individuals. Genotyping was carried out using either Axiom Genome-Wide TWB 2.0 Array Plate-based or polymerase chain reaction-based methods on genomic DNA derived from collected tissue samples. Statistical analyses involved descriptive statistics, Kaplan-Meier analyses, and Cox proportional hazard analyses. From the GWAS, potential genetic predictors, GALNT14-rs62139523 and DNMBP-rs10786578 genotypes, of 5-FU-based adjuvant therapy following surgery in intermediate-stage CRC patients were identified. Validation in a larger cohort of 195 patients emphasized the predictive significance of GALNT14-rs62139523 genotypes, especially the "A/G" genotype, for improved overall and progression-free survival. This predictive association remained robust across various subgroups, with exceptions for specific demographic and clinical parameters such as age < 58 years old, CEA ≤ 2.5 ng/mL, tumor diameter > 44.0 mm, and tumor-free margin ≥ 50 mm. This study identifies that the GALNT14-rs62139523 "A/G" genotype modulates therapeutic outcomes, establishing it as a promising biomarker for predicting favorable responses to 5-FU-based adjuvant chemotherapy in intermediate-stage CRC patients, although further investigations are needed to detail these mechanisms.


Assuntos
Neoplasias Colorretais , Fluoruracila , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/patologia , Fluoruracila/uso terapêutico , Quimioterapia Adjuvante/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/genética , Estudos Retrospectivos , Adulto , Genótipo , N-Acetilgalactosaminiltransferases/genética , Prognóstico , Resultado do Tratamento
14.
Neuron ; 112(13): 2157-2176.e12, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38697111

RESUMO

Mutations in human nonsense-mediated mRNA decay (NMD) factors are enriched in neurodevelopmental disorders. We show that deletion of key NMD factor Upf2 in mouse embryonic neural progenitor cells causes perinatal microcephaly but deletion in immature neurons does not, indicating NMD's critical roles in progenitors. Upf2 knockout (KO) prolongs the cell cycle of radial glia progenitor cells, promotes their transition into intermediate progenitors, and leads to reduced upper-layer neurons. CRISPRi screening identified Trp53 knockdown rescuing Upf2KO progenitors without globally reversing NMD inhibition, implying marginal contributions of most NMD targets to the cell cycle defect. Integrated functional genomics shows that NMD degrades selective TRP53 downstream targets, including Cdkn1a, which, without NMD suppression, slow the cell cycle. Trp53KO restores the progenitor cell pool and rescues the microcephaly of Upf2KO mice. Therefore, one physiological role of NMD in the developing brain is to degrade selective TRP53 targets to control progenitor cell cycle and brain size.


Assuntos
Encéfalo , Camundongos Knockout , Células-Tronco Neurais , Degradação do RNAm Mediada por Códon sem Sentido , Proteína Supressora de Tumor p53 , Animais , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética , Camundongos , Encéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido/genética , Epistasia Genética , Microcefalia/genética , Ciclo Celular/fisiologia , Ciclo Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética
16.
iScience ; 27(3): 109122, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38414863

RESUMO

During aging, blood cell production becomes dominated by a limited number of variant hematopoietic stem cell (HSC) clones. Differentiated progeny of variant HSCs are thought to mediate the detrimental effects of such clonal hematopoiesis on organismal health, but the mechanisms are poorly understood. While somatic mutations in DNA methyltransferase 3A (DNMT3A) frequently drive clonal dominance, the aging milieu also likely contributes. Here, we examined in mice the interaction between high-fat diet (HFD) and reduced DNMT3A in hematopoietic cells; strikingly, this combination led to weight gain. HFD amplified pro-inflammatory pathways and upregulated inflammation-associated genes in mutant cells along a pro-myeloid trajectory. Aberrant DNA methylation during myeloid differentiation and in response to HFD led to pro-inflammatory activation and maintenance of stemness genes. These findings suggest that reduced DNMT3A in hematopoietic cells contributes to weight gain, inflammation, and metabolic dysfunction, highlighting a role for DNMT3A loss in the development of metabolic disorders.

17.
Sci Adv ; 10(8): eadk3127, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38394203

RESUMO

Epigenetic dysregulation has been reported in multiple cancers including leukemias. Nonetheless, the roles of the epigenetic reader Tudor domains in leukemia progression and therapy remain unexplored. Here, we conducted a Tudor domain-focused CRISPR screen and identified SGF29, a component of SAGA/ATAC acetyltransferase complexes, as a crucial factor for H3K9 acetylation, ribosomal gene expression, and leukemogenesis. To facilitate drug development, we integrated the CRISPR tiling scan with compound docking and molecular dynamics simulation, presenting a generally applicable strategy called CRISPR-Scan Assisted Drug Discovery (CRISPR-SADD). Using this approach, we identified a lead inhibitor that selectively targets SGF29's Tudor domain and demonstrates efficacy against leukemia. Furthermore, we propose that the structural genetics approach used in our study can be widely applied to diverse fields for de novo drug discovery.


Assuntos
Leucemia , Domínio Tudor , Humanos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Acetiltransferases/metabolismo , Descoberta de Drogas , Leucemia/tratamento farmacológico , Leucemia/genética
18.
J Hematol Oncol ; 17(1): 7, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302992

RESUMO

BACKGROUND: While liver cancer stem cells (CSCs) play a crucial role in hepatocellular carcinoma (HCC) initiation, progression, recurrence, and treatment resistance, the mechanism underlying liver CSC self-renewal remains elusive. We aim to characterize the role of Methyltransferase 16 (METTL16), a recently identified RNA N6-methyladenosine (m6A) methyltransferase, in HCC development/maintenance, CSC stemness, as well as normal hepatogenesis. METHODS: Liver-specific Mettl16 conditional KO (cKO) mice were generated to assess its role in HCC pathogenesis and normal hepatogenesis. Hydrodynamic tail-vein injection (HDTVi)-induced de novo hepatocarcinogenesis and xenograft models were utilized to determine the role of METTL16 in HCC initiation and progression. A limiting dilution assay was utilized to evaluate CSC frequency. Functionally essential targets were revealed via integrative analysis of multi-omics data, including RNA-seq, RNA immunoprecipitation (RIP)-seq, and ribosome profiling. RESULTS: METTL16 is highly expressed in liver CSCs and its depletion dramatically decreased CSC frequency in vitro and in vivo. Mettl16 KO significantly attenuated HCC initiation and progression, yet only slightly influenced normal hepatogenesis. Mechanistic studies, including high-throughput sequencing, unveiled METTL16 as a key regulator of ribosomal RNA (rRNA) maturation and mRNA translation and identified eukaryotic translation initiation factor 3 subunit a (eIF3a) transcript as a bona-fide target of METTL16 in HCC. In addition, the functionally essential regions of METTL16 were revealed by CRISPR gene tiling scan, which will pave the way for the development of potential inhibitor(s). CONCLUSIONS: Our findings highlight the crucial oncogenic role of METTL16 in promoting HCC pathogenesis and enhancing liver CSC self-renewal through augmenting mRNA translation efficiency.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células-Tronco Neoplásicas , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Autorrenovação Celular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metiltransferases/genética , Metiltransferases/metabolismo , Células-Tronco Neoplásicas/patologia , Biossíntese de Proteínas , Ribossomos/metabolismo , RNA
19.
Nat Struct Mol Biol ; 31(3): 465-475, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316881

RESUMO

The plasma membrane is enriched for receptors and signaling proteins that are accessible from the extracellular space for pharmacological intervention. Here we conducted a series of CRISPR screens using human cell surface proteome and integrin family libraries in multiple cancer models. Our results identified ITGAV (integrin αV) and its heterodimer partner ITGB5 (integrin ß5) as the essential integrin α/ß pair for cancer cell expansion. High-density CRISPR gene tiling further pinpointed the integral pocket within the ß-propeller domain of ITGAV for integrin αVß5 dimerization. Combined with in silico compound docking, we developed a CRISPR-Tiling-Instructed Computer-Aided (CRISPR-TICA) pipeline for drug discovery and identified Cpd_AV2 as a lead inhibitor targeting the ß-propeller central pocket of ITGAV. Cpd_AV2 treatment led to rapid uncoupling of integrin αVß5 and cellular apoptosis, providing a unique class of therapeutic action that eliminates the integrin signaling via heterodimer dissociation. We also foresee the CRISPR-TICA approach to be an accessible method for future drug discovery studies.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Membrana Celular
20.
bioRxiv ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37693622

RESUMO

The DNA damage response is critical for maintaining genome integrity and is commonly disrupted in the development of cancer. PPM1D (protein phosphatase, Mg2+/Mn2+ dependent 1D) is a master negative regulator of the response; gain-of-function mutations and amplifications of PPM1D are found across several human cancers making it a relevant pharmacologic target. Here, we used CRISPR/Cas9 screening to identify synthetic-lethal dependencies of PPM1D, uncovering superoxide dismutase-1 (SOD1) as a potential target for PPM1D-mutant cells. We revealed a dysregulated redox landscape characterized by elevated levels of reactive oxygen species and a compromised response to oxidative stress in PPM1D-mutant cells. Altogether, our results demonstrate the protective role of SOD1 against oxidative stress in PPM1D-mutant leukemia cells and highlight a new potential therapeutic strategy against PPM1D-mutant cancers.

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