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1.
EMBO J ; 43(8): 1570-1590, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499787

RESUMO

Ten-eleven translocation (TET) proteins are dioxygenases that convert 5-methylcytosine (5mC) into 5-hydroxylmethylcytosine (5hmC) in DNA and RNA. However, their involvement in adult stem cell regulation remains unclear. Here, we identify a novel enzymatic activity-independent function of Tet in the Drosophila germline stem cell (GSC) niche. Tet activates the expression of Dpp, the fly homologue of BMP, in the ovary stem cell niche, thereby controlling GSC self-renewal. Depletion of Tet disrupts Dpp production, leading to premature GSC loss. Strikingly, both wild-type and enzyme-dead mutant Tet proteins rescue defective BMP signaling and GSC loss when expressed in the niche. Mechanistically, Tet interacts directly with Bap55 and Stat92E, facilitating recruitment of the Polybromo Brahma associated protein (PBAP) complex to the dpp enhancer and activating Dpp expression. Furthermore, human TET3 can effectively substitute for Drosophila Tet in the niche to support BMP signaling and GSC self-renewal. Our findings highlight a conserved novel catalytic activity-independent role of Tet as a scaffold protein in supporting niche signaling for adult stem cell self-renewal.


Assuntos
Dioxigenases , Proteínas de Drosophila , Drosophila melanogaster , Animais , Feminino , Humanos , Diferenciação Celular/genética , Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Células Germinativas/metabolismo , Nicho de Células-Tronco/fisiologia , Células-Tronco/metabolismo , Dioxigenases/metabolismo
2.
Chemphyschem ; : e202400522, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143702

RESUMO

The long-emission-lifetime nature of room-temperature phosphorescence (RTP) materials lays the foundation of their applications in diverse areas. Despite the advantage of mechanical property, processability and solvent dispersity, the emission lifetimes of polymer-based room-temperature phosphorescence materials remain not particularly long because of the labile nature of organic triplet excited states under ambient conditions. Specifically, ambient phosphorescence lifetime (τP) longer than 2 s and even 4 s have rarely been reported in polymer systems. Here, luminescent compounds with small phosphorescence rate on the order of approximately 10-1 s-1 are designed, ethylene-vinyl alcohol copolymer (EVOH) as polymer matrix and antioxidant 1010 to protect organic triplets are employed, and ultralong phosphorescence lifetime up to 4.6 s under ambient conditions by short-term and low-power excitation are achieved. The resultant materials exhibit high afterglow brightness, long afterglow duration, excellent processability into large area thin films, high transparency and thermal stability, which display promising anticounterfeiting and data encryption functions.

3.
J Chem Inf Model ; 64(3): 761-774, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38215394

RESUMO

Metal complexes exhibit a diverse range of coordination geometries, representing novel privileged scaffolds with convenient click types of preparation inaccessible for typical carbon-centered organic compounds. Herein, we explored the opportunity to identify biologically active organometallic complexes by reverse docking of a rigid, minimum-size octahedral organoruthenium scaffold against thousands of protein-binding pockets. Interestingly, cannabinoid receptor type 1 (CB1) was identified based on the docking scores and the degree of overlap between the docked organoruthenium scaffold and the hydrophobic scaffold of the cocrystallized ligand. Further structure-based optimization led to the discovery of organoruthenium complexes with nanomolar binding affinities and high selectivity toward CB2. Our work indicates that octahedral organoruthenium scaffolds may be advantageous for targeting the large and hydrophobic binding pockets and that the reverse docking approach may facilitate the discovery of novel privileged scaffolds, such as organometallic complexes, for exploring chemical space in lead discovery.


Assuntos
Desenho de Fármacos , Receptor CB2 de Canabinoide , Receptores de Canabinoides/química , Receptores de Canabinoides/metabolismo , Ligação Proteica , Ligantes , Receptor CB2 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/metabolismo
4.
Proc Natl Acad Sci U S A ; 117(7): 3603-3609, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32015133

RESUMO

5-Methylcytosine (m5C) is a RNA modification that exists in tRNAs and rRNAs and was recently found in mRNAs. Although it has been suggested to regulate diverse biological functions, whether m5C RNA modification influences adult stem cell development remains undetermined. In this study, we show that Ypsilon schachtel (YPS), a homolog of human Y box binding protein 1 (YBX1), promotes germ line stem cell (GSC) maintenance, proliferation, and differentiation in the Drosophila ovary by preferentially binding to m5C-containing RNAs. YPS is genetically demonstrated to function intrinsically for GSC maintenance, proliferation, and progeny differentiation in the Drosophila ovary, and human YBX1 can functionally replace YPS to support normal GSC development. Highly conserved cold-shock domains (CSDs) of YPS and YBX1 preferentially bind to m5C RNA in vitro. Moreover, YPS also preferentially binds to m5C-containing RNAs, including mRNAs, in germ cells. The crystal structure of the YBX1 CSD-RNA complex reveals that both hydrophobic stacking and hydrogen bonds are critical for m5C binding. Overexpression of RNA-binding-defective YPS and YBX1 proteins disrupts GSC development. Taken together, our findings show that m5C RNA modification plays an important role in adult stem cell development.


Assuntos
5-Metilcitosina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Óvulo/crescimento & desenvolvimento , RNA/metabolismo , Animais , Proliferação de Células , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Humanos , Ovário/metabolismo , Óvulo/metabolismo , RNA/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteína 1 de Ligação a Y-Box/genética , Proteína 1 de Ligação a Y-Box/metabolismo
5.
Angew Chem Int Ed Engl ; 62(21): e202300980, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36942404

RESUMO

Organic room temperature phosphorescence (RTP) attracts extensive attentions, but still faces the challenge of achieving both high RTP efficiencies (ηRTP ) and long lifetimes (τRTP ), due to the intrinsic contradiction between triplet radiation and stabilization. In this work, we developed three carbazole-triphenylphosphine hybrids named xCzTPP, in which phosphine groups provide nonbonding electrons and steric hindrance to modulate intermolecular p-π and π-π interactions. With the rational orientations and spatial positions of functional groups, para-substituted pCzTPP achieves high ηRTP over 10 % and more than twofold increased τRTP (>600 ms), compared to ortho- and meta- isomers. Theoretical simulation and photophysical investigation indicate that the strongest intermolecular p-π and π-π electronic interplays of pCzTPP harmonize high transition probability of 3 pπ state and triplet stability of 3 ππ state, reflecting the p-π and π-π synergy in RTP process.

6.
BMC Genomics ; 23(1): 524, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35854220

RESUMO

BACKGROUND: Drought stress is a serious threat to land use efficiency and crop yields worldwide. Understanding the mechanisms that plants use to withstand drought stress will help breeders to develop drought-tolerant medicinal crops. Liquorice (Glycyrrhiza uralensis Fisch.) is an important medicinal crop in the legume family and is currently grown mostly in northwest China, it is highly tolerant to drought. Given this, it is considered an ideal crop to study plant stress tolerance and can be used to identify drought-resistant proteins. Therefore, to understand the effects of drought stress on protein levels of liquorice, we undertook a comparative proteomic analysis of liquorice seedlings grown for 10 days in soil with different relative water content (SRWC of 80%, 65%, 50% and 35%, respectively). We used an integrated approach of Tandem Mass Tag labeling in conjunction with LC-MS/MS. RESULTS: A total of 7409 proteins were identified in this study, of which 7305 total proteins could be quantified. There were 837 differentially expressed proteins (DEPs) identified after different drought stresses. Compared with CK, 123 DEPs (80 up-regulated and 43 down-regulated) were found in LS; 353 DEPs (254 up-regulated and 99 down-regulated) in MS; and 564 DEPs (312 up-regulated and 252 down-regulated) in SS.The number of differentially expressed proteins increased with increasing water stress, and the number of up-regulated proteins was higher than that of down-regulated proteins in the different drought stress treatments compared with the CK. Used systematic bioinformatics analysis of these data to identify informative proteins we showed that osmolytes such as cottonseed sugars and proline accumulated under light drought stress and improved resistance. Under moderate and severe drought stress, oxidation of unsaturated fatty acids and accumulation of glucose and galactose increased in response to drought stress. Under moderate and severe drought stress synthesis of the terpene precursors, pentacene 2,3-epoxide and ß-coumarin, was inhibited and accumulation of triterpenoids (glycyrrhetinic acid) was also affected. CONCLUSIONS: These data provide a baseline reference for further study of the downstream liquorice proteome in response to drought stress. Our data show that liquorice roots exhibit specific response mechanisms to different drought stresses.


Assuntos
Secas , Glycyrrhiza , Cromatografia Líquida , Regulação da Expressão Gênica de Plantas , Glycyrrhiza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Estresse Fisiológico , Espectrometria de Massas em Tandem
7.
Mol Cancer ; 21(1): 84, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35337339

RESUMO

BACKGROUND: Immune checkpoint inhibitors had a great effect in triple-negative breast cancer (TNBC); however, they benefited only a subset of patients, underscoring the need to co-target alternative pathways and select optimal patients. Herein, we investigated patient subpopulations more likely to benefit from immunotherapy and inform more effective combination regimens for TNBC patients. METHODS: We conducted exploratory analyses in the FUSCC cohort to characterize a novel patient selection method and actionable targets for TNBC immunotherapy. We investigated this in vivo and launched a phase 2 trial to assess the clinical value of such criteria and combination regimen. Furthermore, we collected clinicopathological and next-generation sequencing data to illustrate biomarkers for patient outcomes. RESULTS: CD8-positivity could identify an immunomodulatory subpopulation of TNBCs with higher possibilities to benefit from immunotherapy, and angiogenesis was an actionable target to facilitate checkpoint blockade. We conducted the phase II FUTURE-C-Plus trial to assess the feasibility of combining famitinib (an angiogenesis inhibitor), camrelizumab (a PD-1 monoclonal antibody) and chemotherapy in advanced immunomodulatory TNBC patients. Within 48 enrolled patients, the objective response rate was 81.3% (95% CI, 70.2-92.3), and the median progression-free survival was 13.6 months (95% CI, 8.4-18.8). No treatment-related deaths were reported. Patients with CD8- and/or PD-L1- positive tumors benefit more from this regimen. PKD1 somatic mutation indicates worse progression-free and overall survival. CONCLUSION: This study confirms the efficacy and safety of the triplet regimen in immunomodulatory TNBC and reveals the potential of combining CD8, PD-L1 and somatic mutations to guide clinical decision-making and treatments. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04129996 . Registered 11 October 2019.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Mama Triplo Negativas , Inibidores da Angiogênese/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/genética , Biomarcadores Tumorais/metabolismo , Humanos , Neovascularização Patológica/tratamento farmacológico , Receptor de Morte Celular Programada 1/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
8.
Endocr Pract ; 27(9): 918-924, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33636393

RESUMO

OBJECTIVE: This study aimed to comprehensively assess the characteristics and risk factors of hyperthyroidism with pulmonary hypertension (PH). METHODS: This was a retrospective cross-sectional analysis of 315 consecutive patients with hyperthyroidism admitted to the endocrinology department of Tongji Hospital from February 2016 to December 2017. PH was defined as a pulmonary arterial systolic pressure above 35 mm Hg measured by echocardiography. RESULTS: Among the 315 patients, 208 were females, the median age was 42 (30-51) years, and the median disease duration was 12 (3-48) months. Thirty-five percent (111/315) of patients were identified with PH. Patients with hyperthyroidism and PH showed significantly higher serum concentrations of free thyroxine (FT4), free triiodothyronine, thyroid receptor antibodies, total bilirubin (TB), direct and indirect bilirubin, lower serum levels of hemoglobin and creatinine, and more severe cardiac load (P < .05 for each) compared with patients without PH. Levels of serum FT4, free triiodothyronine, thyroid receptor antibodies, and thyroid peroxidase antibody were different among groups of patients with different levels of pulmonary arterial systolic pressure (P < .05 for each). Multivariate logistic regression analysis indicated that serum FT4 (odds ratio, 1.02; 95% CI, 1.01-1.04; P = .004) and TB (OR, 1.03; 95% CI, 1.00-1.06; P = .030) were independent risk factors for PH in patients with hyperthyroidism. CONCLUSION: Elevated serum FT4 and TB levels may be independent risk factors for PH in patients with hyperthyroidism and valuable indicators for the identification and treatment of patients with PH and hyperthyroidism.


Assuntos
Hipertensão Pulmonar , Hipertireoidismo , Adulto , Estudos Transversais , Feminino , Humanos , Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/etiologia , Hipertireoidismo/complicações , Hipertireoidismo/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Tireotropina , Tiroxina , Tri-Iodotironina
9.
Mol Carcinog ; 59(1): 126-135, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31713931

RESUMO

Fibrous sheath interacting protein 1 (FSIP1) is frequently activated in a variety of tumors including breast cancer. However, the clinical significance of FSIP1 in hormone receptor (HR)-positive breast cancer is unclear. We analyzed the expression and clinical significance of FSIP1 in human breast cancer databases. A comprehensive analysis of 1094 gene expression profiles of breast cancer in The Cancer Genome Atlas revealed that FSIP1 overexpression correlated with decreased overall survival in HR-positive breast cancer patients. We also showed that knockdown of FSIP1 in T47D and BT474 cell lines resulted in decreased cell proliferation and migration in vitro. Furthermore, we retrospectively examined the expression and prognostic value of FSIP1 in 129 breast cancer patients to examine the expression of FSIP1 by the immunohistochemical method and got the similar results that high expression of FSIP1 predicts poor prognosis. Therefore, FSIP1 has a crucial role in HR-positive breast cancer and represents an attractive therapeutic target for HR-positive breast cancer.


Assuntos
Neoplasias da Mama/genética , Proteínas de Transporte/genética , Regulação Neoplásica da Expressão Gênica , Receptores de Estrogênio/análise , Proteínas de Plasma Seminal/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Proteínas de Transporte/análise , Linhagem Celular Tumoral , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Prognóstico , Proteínas de Plasma Seminal/análise , Transcriptoma , Regulação para Cima
10.
Cancer Cell Int ; 20: 86, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32206037

RESUMO

BACKGROUND: Papillary carcinoma is an uncommon type of breast cancer. Additionally, patients with huge breast papillary carcinoma are extremely rare in clinical practice. To improve therapeutic effect on such patients, it is urgent to explore biologically and clinically relevant models of the disease to discover effective drugs. METHODS: We collected surgical tumor specimens from a 63-year-old Chinese woman who has been diagnosed breast papillary carcinoma. The tumor was more than 15 cm in diameter, and applied to establish patient-derived papillary carcinoma organoids that could continuously propagate for more than 6 months. RESULTS: The papillary carcinoma organoids matched the histological characteristics of orginal tumor by H&E staining identification, and maintained the expression of the breast cancer biomarkers by IHC, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER2) and antigen Ki-67 (Ki67). In addition, we performed a 3-D drug screening to examine the effects of endocrine drugs (Fulvestrant, Tamoxifen) and targeted therapy drugs (Palbociclib, Everolimus, BKM120) on breast papillary carcinoma in the mimic in vivo environment. The drug sensitivities of our breast papillary carcinoma organoids were investigated as follows, Fulvestrant (IC50 0.275 µmol), Palbociclib (IC50 2.21 µmol), BKM120 (IC50 3.81 µmol), Everolimus (IC50 4.45 µmol), Tamoxifen (IC50 19.13 µmol). CONCLUSIONS: These results showed that an effective organoid platform for 3-D in vitro culture of breast cancer organoids from patients with breast papillary carcinoma could be used to identify possible treatments, and might be commonly applied to explore clinicopathological characteristics of breast papillary carcinoma.

11.
Nature ; 514(7521): 233-6, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25119050

RESUMO

The balance between stem cell self-renewal and differentiation is controlled by intrinsic factors and niche signals. In the Drosophila melanogaster ovary, some intrinsic factors promote germline stem cell (GSC) self-renewal, whereas others stimulate differentiation. However, it remains poorly understood how the balance between self-renewal and differentiation is controlled. Here we use D. melanogaster ovarian GSCs to demonstrate that the differentiation factor Bam controls the functional switch of the COP9 complex from self-renewal to differentiation via protein competition. The COP9 complex is composed of eight Csn subunits, Csn1-8, and removes Nedd8 modifications from target proteins. Genetic results indicated that the COP9 complex is required intrinsically for GSC self-renewal, whereas other Csn proteins, with the exception of Csn4, were also required for GSC progeny differentiation. Bam-mediated Csn4 sequestration from the COP9 complex via protein competition inactivated the self-renewing function of COP9 and allowed other Csn proteins to promote GSC differentiation. Therefore, this study reveals a protein-competition-based mechanism for controlling the balance between stem cell self-renewal and differentiation. Because numerous self-renewal factors are ubiquitously expressed throughout the stem cell lineage in various systems, protein competition may function as an important mechanism for controlling the self-renewal-to-differentiation switch.


Assuntos
Ligação Competitiva , Diferenciação Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Complexo do Signalossomo COP9 , Proliferação de Células , DNA Helicases/metabolismo , Proteínas de Drosophila/metabolismo , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteína NEDD8 , Ovário/citologia , Ligação Proteica , Ubiquitinas/metabolismo
12.
Development ; 143(23): 4312-4323, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27729408

RESUMO

Stem cells in adult tissues are constantly exposed to genotoxic stress and also accumulate DNA damage with age. However, it remains largely unknown how DNA damage affects both stem cell self-renewal and differentiation. In this study, we show that DNA damage retards germline stem cell (GSC) self-renewal and progeny differentiation in a Lok kinase-dependent manner in the Drosophila ovary. Both heatshock-inducible endonuclease I-CreI expression and X-ray irradiation can efficiently introduce double-strand breaks in GSCs and their progeny, resulting in a rapid GSC loss and a GSC progeny differentiation defect. Surprisingly, the elimination of Lok or its kinase activity can almost fully rescue the GSC loss and the progeny differentiation defect caused by DNA damage induced by I-CreI or X-ray. In addition, the reduction in bone morphogenetic protein signaling and Shotgun expression only makes a limited contribution to DNA damage-induced GSC loss. Finally, DNA damage also decreases the expression of the master differentiation factor Bam in a Lok-dependent manner, which helps explain the GSC progeny differentiation defect. Therefore, this study demonstrates, for the first time in vivo, that Lok kinase activation is required for the DNA damage-mediated disruption of adult stem cell self-renewal and lineage differentiation, and might also offer novel insight into how DNA damage causes tissue aging and cancer formation.


Assuntos
Diferenciação Celular/fisiologia , Autorrenovação Celular/fisiologia , Quinase do Ponto de Checagem 2/metabolismo , Dano ao DNA/genética , Proteínas de Drosophila/metabolismo , Células Germinativas/citologia , Células-Tronco/citologia , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Linhagem da Célula/genética , Transformação Celular Neoplásica/genética , Quinase do Ponto de Checagem 2/genética , Enzimas de Restrição do DNA/metabolismo , Desoxirribonuclease I/metabolismo , Drosophila , Proteínas de Drosophila/genética , Ativação Enzimática
13.
J Transl Med ; 17(1): 73, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849973

RESUMO

BACKGROUND: Previous studies from this as well as other research groups suggested that non-invasive chromosome screening (NICS) with embryo culture medium can be used to identify chromosomal ploidy and chromosomal abnormalities. We here report a series of clinical cases utilizing the technology. METHODS: A total of 45 couples underwent in vitro fertilisation during a period between February 2016 and February 2017. Karyotyping revealed normal chromosomes in both partners in 23 couples, and chromosomal rearrangements in at least one partner in 22 couples. Intracytoplasmic sperm injection (ICSI) was used for fertilization. NICS was carried out using embryo culture medium at the blastocyst stage via multiple annealing and looping-based amplification cycles, whole-genome amplification and next-generation sequencing. RESULTS: A total of 413 embryos were obtained; 170 blastocysts were subjected to NICS. The screening showed euploidy in 79 embryos, aneuploidy in 52 embryos, and mosaic ploidy for 33 embryos. The rate of euploidy was comparable in couples with normal karyotype (50.7%; 38/75) vs. chromosomal rearrangement (43.2%; 41/95). A total of 52 euploid embryos (50 oocyte retrieval cycles) were transferred in 43 women. Biochemical pregnancy rate was 72.0% (36/50). Clinical pregnancy rate was 58.0% (29/50). The rate of spontaneous miscarriage was 3/29 (none with chromosomal aneuploidy). A total of 27 healthy babies were delivered. CONCLUSIONS: NICS could identify embryo chromosomal abnormalities in couples either with or without chromosomal rearrangement, with satisfying clinical outcomes.


Assuntos
Cromossomos Humanos/genética , Meios de Cultura/química , Embrião de Mamíferos/metabolismo , Fertilização in vitro , Adulto , Feminino , Humanos , Projetos Piloto , Gravidez , Resultado da Gravidez , Adulto Jovem
14.
Mol Pharm ; 16(10): 4213-4222, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31424939

RESUMO

Cancer results from cell proliferation that exceeds normal growth control. There are various specific proteins that control and regulate the cell cycle, such as cyclin-dependent kinases (CDKs), cyclins, and retinoblastoma protein (pRb). The aberration of the cyclin D-CDK4/6-INK4-pRb pathway occurs frequently in cancers; thus, CDK4/6 is an attractive target for the development of radiopharmaceuticals for tumor imaging. In this study, we chose palbociclib, which was approved by the FDA for treating ER+/HER2- advanced breast cancer as the target vector and the isonitrile group, which can coordinate strongly with the [99mTc(CO)3]+ core as the bifunctional chelator, to develop four novel 99mTc-labeled radiotracers for tumor imaging. The ligands (L2, L3, L4, and L5) were synthesized by reacting palbociclib with isocyanide-containing active esters and then radiolabeling with a [99mTc(CO)3]+ core to produce radiotracers (99mTc-L2, 99mTc-L3, 99mTc-L4, and 99mTc-L5) with high radiochemical purity (>95%) and good stability in vitro. The structures of the 99mTc complexes were identified by preparation and characterization of the corresponding stable rhenium complexes. Partition coefficient results indicated that these complexes were lipophilic. A kinase inhibition assay demonstrated the high affinity of the stable Re complexes for CDK4. A cell study showed that all four complexes had substantial uptake by MCF-7 cells and could be significantly inhibited by palbociclib and nonradiolabeled ligand, indicating a CDK4/6-specific uptake mechanism. Biodistribution studies in nude mice bearing MCF-7 tumors showed that the complexes had obvious accumulation in tumors at 2 h postinjection. 99mTc-L2 exhibited the highest tumor uptake and tumor/blood ratio, whereas 99mTc-L4 showed the highest tumor/muscle ratio. The micro-SPECT/CT study showed that complex 99mTc-L4 had visible uptake at the tumor site, and the accumulation was clearly reduced in the image after pretreatment with palbociclib, further indicating CDK4/6 specificity. All the results showed that the 99mTc-labeled complexes in this work have the potential for tumor imaging.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Piperazinas/química , Piperazinas/farmacologia , Piridinas/química , Piridinas/farmacologia , Animais , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Compostos Radiofarmacêuticos/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Proc Natl Acad Sci U S A ; 113(42): 11907-11912, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27688762

RESUMO

Preimplantation genetic screening (PGS) is widely used to select in vitro-fertilized embryos free of chromosomal abnormalities and to improve the clinical outcome of in vitro fertilization (IVF). A disadvantage of PGS is that it requires biopsy of the preimplantation human embryo, which can limit the clinical applicability of PGS due to the invasiveness and complexity of the process. Here, we present and validate a noninvasive chromosome screening (NICS) method based on sequencing the genomic DNA secreted into the culture medium from the human blastocyst. By using multiple annealing and looping-based amplification cycles (MALBAC) for whole-genome amplification (WGA), we performed next-generation sequencing (NGS) on the spent culture medium used to culture human blastocysts (n = 42) and obtained the ploidy information of all 24 chromosomes. We validated these results by comparing each with their corresponding whole donated embryo and obtained a high correlation for identification of chromosomal abnormalities (sensitivity, 0.882, and specificity, 0.840). With this validated NICS method, we performed chromosome screening on IVF embryos from seven couples with balanced translocation, azoospermia, or recurrent pregnancy loss. Six of them achieved successful clinical pregnancies, and five have already achieved healthy live births thus far. The NICS method avoids the need for embryo biopsy and therefore substantially increases the safety of its use. The method has the potential of much wider chromosome screening applicability in clinical IVF, due to its high accuracy and noninvasiveness.


Assuntos
Mapeamento Cromossômico , Embrião de Mamíferos , Fertilização in vitro , Genoma Humano , Genômica , Sequenciamento Completo do Genoma , Adulto , Blastocisto/citologia , Blastocisto/metabolismo , Meios de Cultivo Condicionados , Técnicas de Cultura Embrionária , Feminino , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Implantação/métodos , Translocação Genética
16.
Development ; 142(24): 4242-52, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26672093

RESUMO

Both stem cell self-renewal and lineage differentiation are controlled extrinsically as well as intrinsically. Germline stem cells (GSCs) in the Drosophila ovary provide an attractive model in which to study both stem cell self-renewal and lineage differentiation at the molecular and cellular level. Recently, we have proposed that escort cells (ECs) form a differentiation niche to control GSC lineage specification extrinsically. However, it remains poorly understood how the maintenance and function of the differentiation niche are regulated at the molecular level. Here, this study reveals a new role of COP9 in the differentiation niche to modulate autocrine Hedgehog (Hh) signaling, thereby promoting GSC lineage differentiation. COP9, which is a highly conserved protein complex composed of eight CSN subunits, catalyzes the removal of Nedd8 protein modification from target proteins. Our genetic results have demonstrated that all the COP9 components and the hh pathway components, including hh itself, are required in ECs to promote GSC progeny differentiation. Interestingly, COP9 is required in ECs to maintain Hh signaling activity, and activating Hh signaling in ECs can partially bypass the requirement for COP9 in GSC progeny differentiation. Finally, both COP9 and Hh signaling in ECs promote GSC progeny differentiation partly by preventing BMP signaling and maintaining cellular processes. Therefore, this study has demonstrated that the COP9-Hh signaling axis operates in the differentiation niche to promote GSC progeny differentiation partly by maintaining EC cellular processes and preventing BMP signaling. This provides new insight into how the function of the differentiation niche is regulated at the molecular level.


Assuntos
Diferenciação Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Células Germinativas/citologia , Proteínas Hedgehog/metabolismo , Complexos Multiproteicos/metabolismo , Ovário/citologia , Peptídeo Hidrolases/metabolismo , Nicho de Células-Tronco , Células-Tronco/citologia , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Complexo do Signalossomo COP9 , Linhagem da Célula , Drosophila melanogaster/metabolismo , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Fosforilação
17.
Mol Pharm ; 15(8): 3417-3424, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29985620

RESUMO

In this study, a d-glucosamine derivative with an isonitrile group (CN5DG) was synthesized and it was chosen to coordinate with 99mTc for preparing 99mTc-CN5DG. 99mTc-CN5DG could be readily obtained with high radiochemical purity (>95%) and had great in vitro stability and metabolic stability in urine. The radiotracer demonstrated a positive response to the administration of glucose and insulin in S180 and A549 tumor cells in vitro, suggesting the mechanism of 99mTc-CN5DG into tumor cells was related to glucose transporters. Biodistribution studies in mice bearing A549 xenografts showed 99mTc-CN5DG had a high tumor uptake and high tumor-to-background ratios. SPECT/CT images further supported its ability for tumor imaging. As a cheap, conveniently made and widely available probe, 99mTc-CN5DG would become a potential "working horse" and be a breakthrough in 99mTc-labeled radiopharmaceuticals for tumor detection.


Assuntos
Glucosamina/administração & dosagem , Neoplasias/diagnóstico por imagem , Compostos de Organotecnécio/administração & dosagem , Tecnécio/administração & dosagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Células A549 , Animais , Feminino , Glucosamina/química , Glucosamina/farmacocinética , Humanos , Camundongos , Neoplasias/patologia , Compostos de Organotecnécio/química , Compostos de Organotecnécio/farmacocinética , Tecnécio/química , Tecnécio/farmacocinética , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Pancreatology ; 17(2): 219-227, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28209258

RESUMO

OBJECTIVE: To investigate the effect of biliary tract external drainage (BTED) on severe acute pancreatitis (SAP) in rats and the relationship with heme oxygenase-1 (HO-1) pathway. METHODS: Thirty SD rats weighing 250-300 g were randomly assigned into five groups (n = 6): sham surgery (SS) group, SAP group, SAP + BTED group, SAP + zinc protoporphyrin IX (ZnPP) group, SAP + BTED + ZnPP group. The SAP model was induced via retrograde injection of 4% sodium taurocholate (1 mL/kg) into biliopancreatic duct through duodenal wall. BTED was performed by inserting a cannula into the bile duct of SAP rats. Tissue and blood samples were collected 24 h after surgery. Pathological changes in organs were scored. The level of amylase, alanine transaminase (ALT), aspartate aminotransferase (AST), diamine oxidase (DAO), lipopolysaccharide (LPS), myeloperoxidase (MPO) and ability to inhibit hydroxyl radical(·OH) in serum were measured. The expression of hemeoxygenase-1 (HO-1), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in tissues were analyzed by RT- PCR and western-blot. RESULTS: Organs damage in SAP rats was significantly alleviated by BTED (p < 0.05). Compared to the SAP group, the serum level of amylase, ALT, AST, DAO, MPO, and LPS were significantly lower in the SAP + BTED group, and the ability to inhibit ·OH was significantly higher (p < 0.05). The BETD treatment led to a significant reduction of TNF-α, IL-6 level and a significant increase of HO-1 level in tissues than in SAP rats (p < 0.05). ZnPP significantly inhibited all above mentioned changes. CONCLUSIONS: BTED protected multiple organs against SAP related injuries via HO-1 upregulation.


Assuntos
Regulação Enzimológica da Expressão Gênica , Heme Oxigenase (Desciclizante)/metabolismo , Pancreatite/complicações , Pancreatite/cirurgia , Animais , Heme Oxigenase (Desciclizante)/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Insuficiência de Múltiplos Órgãos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
19.
J Sep Sci ; 38(1): 25-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25354295

RESUMO

Sulfur fumigation may induce the decrease or the chemical transformation of some active ingredients of traditional Chinese medicines in vitro. Whether sulfur fumigation can cause the pharmacokinetic changes of the active ingredients in vivo is related to the efficacy and the safety of Chinese medicines' application clinically. A sensitive, specific, and accurate method for the simultaneous determination of paeoniflorin, ferulic acid, senkyunolide A, and senkyunolide I in rat plasma by ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry was developed to evaluate the influence of sulfur fumigation to Si Wu Tang for the first time. Each compound was extracted from plasma samples by liquid-liquid extraction with ethyl acetate, and the chromatographic separation was accomplished on an Agilent Extend C18 column with a linear gradient elution. The mass spectrometric detection and analysis were performed by using an AB Sciex triple quadrupole 5500 mass spectrometer in multiple reaction monitoring mode. The validated method was successfully applied to a pharmacokinetic study of four compounds in rats after oral administration of sun-dried and sulfur-fumigated Si Wu Tang. The results provided a meaningful basis for evaluating the affection of sulfur fumigation to the clinical application and the efficacy of Si Wu Tang.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/farmacocinética , Espectrometria de Massas/métodos , Enxofre/química , Animais , Benzofuranos/sangue , Benzofuranos/farmacocinética , Ácidos Cumáricos/sangue , Ácidos Cumáricos/farmacocinética , Fumigação , Glucosídeos/sangue , Glucosídeos/farmacocinética , Masculino , Monoterpenos/sangue , Monoterpenos/farmacocinética , Ratos , Ratos Sprague-Dawley
20.
Lasers Med Sci ; 30(8): 2077-86, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25759232

RESUMO

We have previously shown that blue light eliminates the black-pigmented oral bacteria Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, and Prevotella melaninogenica. In the present study, the in vitro photosensitivity of the above black-pigmented microorganisms and four Fusobacteria species (Fusobacterium nucleatum ss. nucleatum, F. nucleatum ss. vincentii, F. nucleatum ss. polymorphum, Fusobacterium periodonticum) was investigated in pure cultures and human dental plaque suspensions. We also tested the hypothesis that phototargeting the above eight key periodontopathogens in plaque-derived biofilms in vitro would control growth within the dental biofilm environment. Cultures of the eight bacteria were exposed to blue light at 455 nm with power density of 80 mW/cm2 and energy fluence of 4.8 J/cm2. High-performance liquid chromatography (HPLC) analysis of bacteria was performed to demonstrate the presence and amounts of porphyrin molecules within microorganisms. Suspensions of human dental plaque bacteria were also exposed once to blue light at 455 nm with power density of 50 mW/cm2 and energy fluence of 12 J/cm2. Microbial biofilms developed from the same plaque were exposed to 455 nm blue light at 50 mW/cm2 once daily for 4 min (12 J/cm2) over a period of 3 days (4 exposures) in order to investigate the cumulative action of phototherapy on the eight photosensitive pathogens as well as on biofilm growth. Bacterial growth was evaluated using the colony-forming unit (CFU) assay. The selective phototargeting of pathogens was studied using whole genomic probes in the checkerboard DNA-DNA format. In cultures, all eight species showed significant growth reduction (p < 0.05). HPLC demonstrated various porphyrin patterns and amounts of porphyrins in bacteria. Following phototherapy, the mean survival fractions were reduced by 28.5 and 48.2% in plaque suspensions and biofilms, respectively, (p < 0.05). DNA probe analysis showed significant reduction in relative abundances of the eight bacteria as a group in plaque suspensions and biofilms. The cumulative blue light treatment suppressed biofilm growth in vitro. This may introduce a new avenue of prophylactic treatment for periodontal diseases.


Assuntos
Biofilmes/efeitos da radiação , Luz , Periodonto/microbiologia , Periodonto/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Contagem de Colônia Microbiana , Placa Dentária/microbiologia , Fusobacterium/efeitos da radiação , Humanos , Viabilidade Microbiana/efeitos da radiação , Fototerapia , Porfirinas/análise
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