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1.
Small ; : e2312141, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801318

RESUMO

Reactive oxygen species (ROS)-mediated emerging treatments exhibit unique advantages in cancer therapy in recent years. While the efficacy of ROS-involved tumor therapy is greatly restricted by complex tumor microenvironment (TME). Herein, a dual-metal CaO2@CDs-Fe (CCF) nanosphere, with TME response and regulation capabilities, are proposed to improve ROS lethal power by a multiple cascade synergistic therapeutic strategy with domino effect. In response to weak acidic TME, CCF will decompose, accompanied with intracellular Ca2+ upregulated and abundant H2O2 and O2 produced to reverse antitherapeutic TME. Then the exposed CF cores can act as both Fenton agent and sonosensitizer to generate excessive ROS in the regulated TME for enhanced synergistic CDT/SDT. In combination with calcium overloading, the augmented ROS induced oxidative stress will cause more severe mitochondrial damage and cellular apoptosis. Furthermore, CCF can also reduce GPX4 expression and enlarge the lipid peroxidation, causing ferroptosis and apoptosis in parallel. These signals of damage will finally initiate damage-associated molecular patterns to activate immune response and to realize excellent antitumor effect. This outstanding domino ROS/calcium loading synergistic effect endows CCF with excellent anticancer effect to efficiently eliminate tumor by apoptosis/ferroptosis/ICD both in vitro and in vivo.

2.
J Org Chem ; 89(16): 11558-11566, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39082143

RESUMO

Efficient copper-catalyzed radical thiocyanosulfonylation of alkenes and alkynes with potassium thiocyanate and sodium phenylsulfinate is described. The reactions provide general and convenient methods toward the synthesis of ß-thiocyanoalkyl sulfones and ß-thiocyanoalkenyl sulfones, respectively, in satisfactory yields. Based on conducted mechanistic experiments, a mechanism involving oxidative generation of sulfonyl radicals and subsequent addition to alkenes followed by Cu-assisted thiocyanation is proposed. Moreover, the practicability of the reaction is successfully demonstrated by its successful application on a gram scale.

3.
J Nanobiotechnology ; 22(1): 313, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840120

RESUMO

Adoptive cellular immunotherapy as a promising and alternative cancer therapy platform is critical for future clinical applications. Natural killer (NK) cells have attracted attention as an important type of innate immune regulatory cells that can rapidly kill multiple adjacent cancer cells. However, these cells are significantly less effective in treating solid tumors than in treating hematological tumors. Herein, we report the synthesis of a Fe3O4-PEG-CD56/Avastin@Ce6 nanoprobe labeled with NK-92 cells that can be used for adoptive cellular immunotherapy, photodynamic therapy and dual-modality imaging-based in vivo fate tracking. The labeled NK-92 cells specifically target the tumor cells, which increases the amount of cancer cell apoptosis in vitro. Furthermore, the in vivo results indicate that the labeled NK-92 cells can be used for tumor magnetic resonance imaging and fluorescence imaging, adoptive cellular immunotherapy, and photodynamic therapy after tail vein injection. These data show that the developed multifunctional nanostructure is a promising platform for efficient innate immunotherapy, photodynamic treatment and noninvasive therapeutic evaluation of breast cancer.


Assuntos
Neoplasias da Mama , Antígeno CD56 , Células Matadoras Naturais , Fotoquimioterapia , Polietilenoglicóis , Neoplasias da Mama/terapia , Humanos , Feminino , Animais , Fotoquimioterapia/métodos , Camundongos , Polietilenoglicóis/química , Linhagem Celular Tumoral , Antígeno CD56/metabolismo , Imunoterapia Adotiva/métodos , Apoptose/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Camundongos Endogâmicos BALB C , Camundongos Nus
4.
J Am Chem Soc ; 144(15): 6802-6812, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35378978

RESUMO

Density functional theory calculations (ωB97X-D) are reported for the reactions of methoxy, tert-butoxy, trichloroethoxy, and trifluoroethoxy radicals with a series of 26 C-H bonds in different environments characteristic of a variety of hydrocarbons and substituted derivatives. The variations in activation barriers are analyzed with modified Evans-Polanyi treatments to account for polarity and unsaturation effects. The treatments by Roberts and Steel and by Mayer have inspired the development of a simple treatment involving the thermodynamics of reactions, the difference between the reactant radical and product radical electronegativities, and the absence or presence of α-unsaturation. The three-parameter equation (ΔH⧧ = 0.52ΔHrxn(1 - d) - 0.35ΔχAB2 + 10.0, where d = 0.44 when there is α-unsaturation to the reacting C-H bond), correlates well with quantum mechanically computed barriers and shows the quantitative importance of the thermodynamics of reactions (dictated by the reactant and the product bond dissociation energies) and polar effects.


Assuntos
Hidrocarbonetos , Hidrogênio , Radicais Livres/química , Hidrocarbonetos/química , Hidrogênio/química , Termodinâmica
5.
Cell Commun Signal ; 20(1): 60, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35525979

RESUMO

Apolipoprotein A-I binding protein (AIBP), a secreted protein, has been shown to play a pivotal role in the development of atherosclerosis. The function of intracellular AIBP, however, is not yet well characterized. Here, we found that AIBP is abundantly expressed within human and mouse atherosclerotic lesions and exhibits a distinct localization in the inner membrane of mitochondria in macrophages. Bone marrow-specific AIBP deficiency promotes the progression of atherosclerosis and increases macrophage infiltration and inflammation in low-density lipoprotein receptor-deficient (LDLR-/-) mice. Specifically, the lack of mitochondrial AIBP leads to mitochondrial metabolic disorders, thereby reducing the formation of mitophagy by promoting the cleavage of PTEN-induced putative kinase 1 (PINK1). With the reduction in mitochondrial autophagy, macrophages polarize to the M1 proinflammatory phenotype, which further promotes the development of atherosclerosis. Based on these results, mitochondrial AIBP in macrophages performs an antiatherosclerotic role by regulating of PINK1-dependent mitophagy and M1/M2 polarization. Video Abstract.


Assuntos
Aterosclerose , Macrófagos , Mitofagia , Fosfoproteínas , Racemases e Epimerases , Animais , Aterosclerose/metabolismo , Polaridade Celular , Macrófagos/metabolismo , Camundongos , Mitocôndrias/metabolismo , Fosfoproteínas/metabolismo , Proteínas Quinases/metabolismo , Racemases e Epimerases/metabolismo
6.
Angew Chem Int Ed Engl ; 61(41): e202208908, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-35989224

RESUMO

We report herein a rare example of enantiodivergent aldehyde addition with ß-alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6-Di-9-anthracenyl-substituted chiral phosphoric acid-catalyzed asymmetric allylation using ß-vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with ß-2-propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate-catalyst C-H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies.


Assuntos
Álcoois , Aldeídos , Catálise , Estereoisomerismo
7.
Angew Chem Int Ed Engl ; 61(9): e202113204, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-34889494

RESUMO

Computations and experiments leading to new chiral phosphoric acids (CPAs) for epoxide thionations are reported. Density functional theory calculations reveal the mechanism and origin of the enantioselectivity of such CPA-catalyzed epoxide thionations. The calculated mechanistic information was used to design new efficient CPAs that were tested experimentally and found to be highly effective. Bulky ortho-substituents on the 3,3'-aryl groups of the CPA are important to restrict the position of the epoxide in the key transition states for the enantioselectivity-determining step. Larger para-substituents significantly improve the enantioselectivity of the reaction.

8.
Angew Chem Int Ed Engl ; 61(48): e202211562, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36107463

RESUMO

Hydrogenation of alkenes is one of the most fundamental transformations in organic synthesis, and widely used in the petrochemical, pharmaceutical, and food industries. Although numerous hydrogenation methods have been developed, novel types of catalysis with new mechanisms and new hydrogen sources are still desirable. Thioxanthone (TX) is widely used in energy-transfer photoreactions, but rarely in photoredox processes. Herein we show that a catalytic amount of TfOH as a co-catalyst can tune the properties of TX to make it a photoredox catalyst with highly enhanced oxidative capability in the hydrogenation of carbonylated alkenes with the cheap petroleum industrial product p-xylene serving as the hydrogen source. Deuterium can also be introduced by this method by using D2 O as the D source. To the best of our knowledge, this is the first example of using p-xylene as a hydrogen source.


Assuntos
Alcenos , Hidrogênio , Hidrogenação , Alcenos/química , Hidrogênio/química , Elétrons , Catálise
9.
J Am Chem Soc ; 143(39): 16041-16054, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34546749

RESUMO

The introduction of thianthrene as a linchpin has proven to be a versatile strategy for the C-H functionalization of aromatic compounds, featuring a broad scope and fast diversification. The synthesis of aryl thianthrenium salts has displayed an unusually high para regioselectivity, notably superior to those observed in halogenation or borylation reactions for various substrates. We report an experimental and computational study on the mechanism of aromatic C-H thianthrenation reactions, with an emphasis on the elucidation of the reactive species and the nature of the exquisite site selectivity. Mechanisms involving a direct attack of arene to the isolated O-trifluoracetylthianthrene S-oxide (TT+-TFA) or to the thianthrene dication (TT2+) via electron transfer under acidic conditions are identified. A reversible interconversion of the different Wheland-type intermediates before a subsequent, irreversible deprotonation is proposed to be responsible for the exceptional para selectivity of the reaction.

10.
BMC Neurosci ; 22(1): 28, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882822

RESUMO

BACKGROUND: Brain radiation exposure, in particular, radiotherapy, can induce cognitive impairment in patients, with significant effects persisting for the rest of their life. However, the main mechanisms leading to this adverse event remain largely unknown. A study of radiation-induced injury to multiple brain regions, focused on the hippocampus, may shed light on neuroanatomic bases of neurocognitive impairments in patients. Hence, we irradiated BALB/c mice (male and female) at postnatal day 3 (P3), day 10 (P10), and day 21 (P21) and investigated the long-term radiation effect on brain MRI changes and hippocampal neurogenesis. RESULTS: We found characteristic brain volume reductions in the hippocampus, olfactory bulbs, the cerebellar hemisphere, cerebellar white matter (WM) and cerebellar vermis WM, cingulate, occipital and frontal cortices, cerebellar flocculonodular WM, parietal region, endopiriform claustrum, and entorhinal cortex after irradiation with 5 Gy at P3. Irradiation at P10 induced significant volume reduction in the cerebellum, parietal region, cingulate region, and olfactory bulbs, whereas the reduction of the volume in the entorhinal, parietal, insular, and frontal cortices was demonstrated after irradiation at P21. Immunohistochemical study with cell division marker Ki67 and immature marker doublecortin (DCX) indicated the reduced cell division and genesis of new neurons in the subgranular zone of the dentate gyrus in the hippocampus after irradiation at all three postnatal days, but the reduction of total granule cells in the stratum granulosun was found after irradiation at P3 and P10. CONCLUSIONS: The early life radiation exposure during different developmental stages induces varied brain pathophysiological changes which may be related to the development of neurological and neuropsychological disorders later in life.


Assuntos
Encéfalo/efeitos da radiação , Irradiação Craniana/efeitos adversos , Neurogênese/efeitos da radiação , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C
11.
Virol J ; 18(1): 135, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215260

RESUMO

BACKGROUND: The relationship between psoriasis and hepatitis C was previously controversial, so our purpose is to investigate this connection. METHODS: We conducted a systematic review of the case-control, cross-sectional and cohort studies examining the association between psoriasis and hepatitis C in PubMed, EMBASE and Cochrane library databases and investigated the overlapping genes between psoriasis targets and hepatitis C targets using bioinformatics analysis. Based on overlapping genes and hub nodes, we also constructed the protein-protein interaction (PPI) network and module respectively, followed by the pathway enrichment analysis. RESULTS: We included 11 publications that reported a total of 11 studies (8 cross-sectional and 3 case-control). The case-control and cross-sectional studies included 25,047 psoriasis patients and 4,091,631 controls in total. Psoriasis was associated with a significant increase of prevalent hepatitis C (OR 1.72; 95% confidence interval [CI] (1.17-2.52)). A total of 389 significant genes were common to both hepatitis C and psoriasis, which mainly involved IL6, TNF, IL10, ALB, STAT3 and CXCL8. The module and pathway enrichment analyses showed that the common genes had the potential to influence varieties of biological pathways, including the inflammatory response, cytokine activity, cytokine-cytokine receptor interaction, Toll-like receptor signaling pathway, which play an important role in the pathogenesis of hepatitis C and psoriasis. CONCLUSION: Patients with psoriasis display increased prevalence of hepatitis C and the basic related mechanisms between hepatitis C and psoriasis had been preliminarily clarified.


Assuntos
Hepatite C , Psoríase , Biologia Computacional , Estudos Transversais , Hepatite C/complicações , Humanos , Mapas de Interação de Proteínas , Psoríase/complicações , Psoríase/virologia
12.
J Org Chem ; 86(15): 9925-9937, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34115516

RESUMO

A kinetic, product, and computational study on the reactions of the cumyloxyl radical with monosubstituted cyclopentanes and cyclohexanes has been carried out. HAT rates, site-selectivities for C-H bond oxidation, and DFT computations provide quantitative information and theoretical models to explain the observed patterns. Cyclopentanes functionalize predominantly at C-1, and tertiary C-H bond activation barriers decrease on going from methyl- and tert-butylcyclopentane to phenylcyclopentane, in line with the computed C-H BDEs. With cyclohexanes, the relative importance of HAT from C-1 decreases on going from methyl- and phenylcyclohexane to ethyl-, isopropyl-, and tert-butylcyclohexane. Deactivation is also observed at C-2 with site-selectivity that progressively shifts to C-3 and C-4 with increasing substituent steric bulk. The site-selectivities observed in the corresponding oxidations promoted by ethyl(trifluoromethyl)dioxirane support this mechanistic picture. Comparison of these results with those obtained previously for C-H bond azidation and functionalizations promoted by the PINO radical of phenyl and tert-butylcyclohexane, together with new calculations, provides a mechanistic framework for understanding C-H bond functionalization of cycloalkanes. The nature of the HAT reagent, C-H bond strengths, and torsional effects are important determinants of site-selectivity, with the latter effects that play a major role in the reactions of oxygen-centered HAT reagents with monosubstituted cyclohexanes.


Assuntos
Cicloexanos , Ciclopentanos , Ligação de Hidrogênio , Cinética , Estrutura Molecular
13.
Angew Chem Int Ed Engl ; 60(45): 24096-24106, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34608723

RESUMO

We report herein the development of stereodivergent syntheses of enantioenriched homoallylic alcohols using chiral nonracemic α-CH2 Bpin-substituted crotylboronate. Chiral phosphoric acid (S)-A-catalyzed asymmetric allyl addition with the reagent gave Z-anti-homoallylic alcohols with excellent enantioselectivities and Z-selectivities. When the enantiomeric acid catalyst (R)-A was utilized, the stereoselectivity was completely reversed and E-anti-homoallylic alcohols were obtained with high E-selectivities and excellent enantioselectivities. By pairing the chirality of the boron reagent with the catalyst, two complementary stereoisomers of chiral homoallylic alcohols can be obtained selectively from the same boron reagent. DFT computational studies were conducted to probe the origins of the observed stereoselectivity. These reactions generate highly enantioenriched homoallylic alcohol products that are valuable for rapid construction of polyketide structural frameworks.

14.
J Am Chem Soc ; 142(43): 18355-18368, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33052047

RESUMO

The development of α,α-disubstituted crotylboronate reagents is reported. Chiral Brønsted acid-catalyzed asymmetric aldehyde addition with the developed E-crotylboron reagent gave (E)-anti-1,2-oxaborinan-3-enes with excellent enantioselectivities and E-selectivities. With BF3·OEt2 catalysis, the stereoselectivity is reversed, and (Z)-δ-boryl-anti-homoallylic alcohols are obtained with excellent Z-selectivities from the same E-crotylboron reagent. The Z-crotylboron reagent also participates in BF3·OEt2-catalyzed crotylation to furnish (Z)-δ-boryl-syn-homoallylic alcohols with good Z-selectivities. DFT computations establish the origins of observed enantio- and stereoselectivities of chiral Brønsted acid-catalyzed asymmetric allylation. Stereochemical models for BF3·OEt2-catalyzed reactions are proposed to rationalize the Z-selective allyl additions. These reactions generate highly valuable homoallylic alcohol products with a stereodefined trisubstituted alkene unit. The synthetic utility is further demonstrated by the total syntheses of salinipyrones A and B.

15.
Angew Chem Int Ed Engl ; 59(26): 10540-10548, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32173972

RESUMO

We report a dual function asymmetric catalysis by a chiral phosphoric acid catalyst that controls both enantioselective addition of an achiral α-vinyl allylboronate to aldehydes and pseudo-axial orientation of the α-vinyl group in the transition state. The reaction produces dienyl homoallylic alcohols with high Z-selectivities and enantioselectivities. Computational studies revealed that minimization of steric interactions between the alkyl groups of the diol on boron and the chiral phosphoric acid catalyst influence the orientation of α-vinyl substituent of the allylboronate reagent to occupy a pseudo-axial position in the transition state.

16.
J Cell Mol Med ; 23(4): 2384-2398, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30677218

RESUMO

O-GlcNAcylation catalysed by O-GlcNAc transferase (OGT) is a reversible post-translational modification. O-GlcNAcylation participates in transcription, epigenetic regulation, and intracellular signalling. Dysregulation of O-GlcNAcylation in response to high glucose or OGT expression has been implicated in metabolic diseases and cancer. However, the underlying mechanisms by which OGT regulates hepatoma development remain largely unknown. Here, we employed the lentiviral shRNA-based system to knockdown OGT to analyse the contribution of OGT in hepatoma cell proliferation and stem-like cell potential. The sphere-forming assay and western blot analysis of stem-related gene expression were used to evaluate stem-like cell potential of hepatoma cell. We found that the level of total O-GlcNAcylation or OGT protein was increased in hepatocellular carcinoma. OGT activated stem-like cell potential in hepatoma through eukaryotic initiation factor 4E (eIF4E) which bound to stem-related gene Sox2 5'-untranslated region. O-GlcNAcylation of eIF4E at threonine 168 and threonine 177 protected it from degradation through proteasome pathway. Expression of eIF4E in hepatoma was determined by immunostaining in 232 HCC patients, and Kaplan-Meier survival analysis was used to determine the correlation of eIF4E expression with prognosis. High glucose promoted stem-like cell potential of hepatoma cell through OGT-eIF4E axis. Collectively, our findings indicate that OGT promotes the stem-like cell potential of hepatoma cell through O-GlcNAcylation of eIF4E. These results provide a mechanism of HCC development and a cue between the pathogenesis of HCC and high glucose condition.


Assuntos
Carcinoma Hepatocelular/genética , Fator de Iniciação 4E em Eucariotos/genética , Neoplasias Hepáticas/genética , N-Acetilglucosaminiltransferases/genética , Acilação/genética , Idoso , Apoptose/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glucose/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/patologia , Prognóstico , Processamento de Proteína Pós-Traducional/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/genética
17.
J Med Virol ; 91(9): 1633-1642, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31081548

RESUMO

BACKGROUND: No comprehensive analysis is available on the viral etiology and clinical characterization among children with severe acute lower respiratory tract infection (SALRTI) in Southern China. METHODS: Cohort of 659 hospitalized children (2 months to 14 years) with SALRTI admitted to the Pediatric Intensive Care Unit (PICU) in the Guangzhou from May 2015 to April 2018 was enrolled in this study. Nasopharyngeal aspirate specimens or induced sputum were tested for eight categories respiratory viral targets. The viral distribution and its clinical characters were statistically analyzed. RESULTS: Viral pathogen was detected in 326 (49.5%) of children with SALRTI and there were 36 (5.5%) viral coinfections. Overall, the groups of viruses identified were, in descending order of prevalence: Influenza virus (IFV) (n = 94, 14.3%), respiratory syncytial virus (RSV) (n = 75, 11.4%), human rhinovirus (HRV) (n = 56, 8.5%), adenovirus (ADV) (n = 55, 8.3%), parainfluenza (PIV) (n = 47, 7.1%), human coronavirus (HCoV) (n = 15, 2.3%), human metapneumovirus (HMPV) (n = 14, 2.1%) and human bocavirus (HBoV) (n = 11, 1.7%). The positive rate in younger children (< 5 years) was significantly higher than the positive rate detected in elder children (> 5 years) (52.5% vs 35.1%, P = 0.001). There were clear seasonal peaks for IFV, RSV, HRV, ADV, PIV, and HMPV. And the individuals with different viral infection varied significantly in terms of clinical profiles. CONCLUSIONS: Viral infections are present in a consistent proportion of patients admitted to the PICU. IFV, RSV, HRV, and ADV accounted for more than two-thirds of all viral SALRTI. Our findings could help the prediction, prevention and potential therapeutic approaches of SALRTI in children.


Assuntos
Criança Hospitalizada , Coinfecção/epidemiologia , Unidades de Terapia Intensiva Pediátrica , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Viroses/epidemiologia , Viroses/virologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , China/epidemiologia , Coinfecção/diagnóstico , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Vigilância em Saúde Pública , Infecções Respiratórias/diagnóstico , Estações do Ano , Fatores Sexuais , Viroses/diagnóstico
18.
Angew Chem Int Ed Engl ; 58(50): 18055-18060, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31549762

RESUMO

Chiral tetrahydrothiophenes and tetrahydroselenophenes are highly useful structural units. Described here is a new catalytic asymmetric approach for their synthesis. With a suitable chiral Brønsted acid catalyst, an oxetane desymmetrization by a well-positioned internal sulfur or selenium nucleophile proceeded efficiently to generate all-carbon quaternary stereocenters with excellent enantioselectivities. Taming the sulfur and selenium nucleophile in the form of a thioester and selenoester, respectively, is crucial to the success of this work. This approach also allows the facile synthesis of chiral tetrahydrothiopyrans. Mechanistic studies, including DFT calculations, suggested an intramolecular acyl-transfer pathway. Utilities of the chiral products are also demonstrated.

19.
J Hepatol ; 69(1): 89-98, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29551704

RESUMO

BACKGROUND & AIMS: Intrahepatic cholangiocarcinoma (ICC) is the second-most lethal primary liver cancer. Little is known about intratumoral heterogeneity (ITH) and its impact on ICC progression. We aimed to investigate the ITH of ICC in the hope of helping to develop new therapeutic strategies. METHODS: We obtained 69 spatially distinct regions from six operable ICCs. Patient-derived primary cancer cells (PDPCs) were established for each region, followed by whole-exome sequencing (WES) and multi-level validation. RESULTS: We observed widespread ITH for both somatic mutations and clonal architecture, shaped by multiple mechanisms, like clonal "illusion", parallel evolution and chromosome instability. A median of 60.3% of mutations were heterogeneous, among which 85% of the driver mutations were located on the branches of tumor phylogenetic trees. Many truncal and clonal driver mutations occurred in tumor suppressor genes, such as TP53, SMARCB1 and PBRM1 that are involved in DNA repair and chromatin-remodeling. Genome doubling occurred in most cases (5/6) after the accumulation of truncal mutations and was shared by all intratumoral sub-regions. In all cases, ongoing chromosomal instability is evident throughout the evolutionary trajectory of ICC. The recurrence of ICC1239 provided evidence to support the polyclonal metastatic seeding in ICC. The change of mutation landscape and internal diversity among subclones during metastasis, such as the loss of chemoresistance mediator, can be used for new treatment strategies. Targeted therapy against truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, was developed in 5/6 patients. CONCLUSIONS: Integrated investigations of spatial ITH and clonal evolution may provide an important molecular foundation for enhanced understanding of tumorigenesis and progression in ICC. LAY SUMMARY: We applied multiregional whole-exome sequencing to investigate the evolution of intrahepatic cholangiocarcinoma (ICC). The results revealed that many factors, such as parallel evolution and chromosome instability, may participate and promote the branch diversity of ICC. Interestingly, in one patient with primary and recurrent metastatic tumors, we found evidence of polyclonal metastatic seeding, indicating that symbiotic communities of multiple clones existed and were maintained during metastasis. More realistically, some truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, could be promising treatment targets in patients with ICC.


Assuntos
Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , Instabilidade Cromossômica/genética , Evolução Clonal/genética , DNA de Neoplasias/genética , Mutação , Idoso , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/patologia , Progressão da Doença , Exoma , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade
20.
Gastroenterology ; 152(1): 232-242.e4, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27639803

RESUMO

BACKGROUND & AIMS: No targeted therapies have been found to be effective against hepatocellular carcinoma (HCC), possibly due to the large degree of intratumor heterogeneity. We performed genetic analyses of different regions of HCCs to evaluate levels of intratumor heterogeneity and associate alterations with responses to different pharmacologic agents. METHODS: We obtained samples of HCCs (associated with hepatitis B virus infection) from 10 patients undergoing curative resection, before adjuvant therapy, at hospitals in China. We collected 4-9 spatially distinct samples from each tumor (55 regions total), performed histologic analyses, isolated cancer cells, and carried them low-passage culture. We performed whole-exome sequencing, copy-number analysis, and high-throughput screening of the cultured primary cancer cells. We tested responses of an additional 105 liver cancer cell lines to a fibroblast growth factor receptor (FGFR) 4 inhibitor. RESULTS: We identified a total of 3670 non-silent mutations (3192 missense, 94 splice-site variants, and 222 insertions or deletions) in the tumor samples. We observed considerable intratumor heterogeneity and branched evolution in all 10 tumors; the mean percentage of heterogeneous mutations in each tumor was 39.7% (range, 12.9%-68.5%). We found significant mutation shifts toward C>T and C>G substitutions in branches of phylogenetic trees among samples from each tumor (P < .0001). Of note, 14 of the 26 oncogenic alterations (53.8%) varied among subclones that mapped to different branches. Genetic alterations that can be targeted by existing pharmacologic agents (such as those in FGF19, DDR2, PDGFRA, and TOP1) were identified in intratumor subregions from 4 HCCs and were associated with sensitivity to these agents. However, cells from the remaining subregions, which did not have these alterations, were not sensitive to these drugs. High-throughput screening identified pharmacologic agents to which these cells were sensitive, however. Overexpression of FGF19 correlated with sensitivity of cells to an inhibitor of FGFR 4; this observation was validated in 105 liver cancer cell lines (P = .0024). CONCLUSIONS: By analyzing genetic alterations in different tumor regions of 10 HCCs, we observed extensive intratumor heterogeneity. Our patient-derived cell line-based model, integrating genetic and pharmacologic data from multiregional cancer samples, provides a platform to elucidate how intratumor heterogeneity affects sensitivity to different therapeutic agents.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Heterogeneidade Genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Variantes Farmacogenômicos , RNA Mensageiro/metabolismo , Antineoplásicos/farmacologia , Azepinas/farmacologia , Sequência de Bases , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Evolução Clonal , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Ensaios de Seleção de Medicamentos Antitumorais , Exoma , Fatores de Crescimento de Fibroblastos/genética , Amplificação de Genes , Humanos , Indazóis/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Mutação de Sentido Incorreto , Filogenia , Cultura Primária de Células , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Deleção de Sequência , Triazóis/farmacologia
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