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1.
Int J Nanomedicine ; 19: 3847-3859, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708182

RESUMO

Background: Dihydroartemisinin (DHA) has emerged as a promising candidate for anticancer therapy. However, the application of DHA in clinics has been hampered by several limitations including poor bioavailability, short circulation life, and low solubility, significantly restricting its therapeutic efficacy and leading to notable side effects during the treatment. Purpose: We present DHA-loaded zeolitic imidazolate framework-8 (D-ZIF) with controllable and targeted DHA release properties, leading to enhanced antitumor effects while reducing potential side effects. Methods: D-ZIF was prepared by one-pot synthesis method using methylimidazole (MIM), Zn(NO3)2•6H2O and DHA. We characterized the physical and chemical properties of D-ZIF by TEM, DLS, XRD, FT-IR, and TG. We measured the drug loading efficiency and the cumulative release of DHA in different pH conditions. We evaluated the cytotoxicity of D-ZIF on renal cell carcinoma (RCC786-O), glioma cells (U251), TAX-resistant human lung adenocarcinoma (A549-TAX) cells by CCK8 in vitro. We explored the possible antitumor mechanism of D-ZIF by Western blot. We evaluated the biocompatibility and hemolysis of D-ZIF and explored the in vivo antitumor efficiency in mice model by TUNEL testing and blood biomarker evaluations. Results: D-ZIF showed rhombic dodecahedral morphology with size of 129±7.2 nm and possessed a noticeable DHA encapsulation efficiency (72.9%). After 48 hours, D-ZIF released a cumulative 70.0% of the loaded DHA at pH 6.5, and only 42.1% at pH 7.4. The pH-triggered programmed release behavior of D-ZIF could enhance anticancer effect of DHA while minimizing side effects under normal physiological conditions. Compared with the free DHA group with 31.75% of A549-TAX cell apoptosis, the percentage of apoptotic cells was approximately 76.67% in the D-ZIF group. D-ZIF inhibited tumor growth by inducing tumor cell apoptosis through the mechanism of ROS production and regulation of Nrf2/HO-1 and P38 MAPK signaling pathways. D-ZIF showed potent effects in treating tumors with high safety in vivo. Conclusion: This pH-responsive release mechanism enhanced the targeting efficiency of DHA towards tumor cells, thereby increasing drug concentration in tumor sites with negligible side effects. Herein, D-ZIF holds great promise for curing cancers with minimal adverse effects.


Assuntos
Antineoplásicos , Artemisininas , Resistencia a Medicamentos Antineoplásicos , Imidazóis , Neoplasias Pulmonares , Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Artemisininas/química , Artemisininas/farmacologia , Artemisininas/farmacocinética , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacocinética , Estruturas Metalorgânicas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Camundongos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Linhagem Celular Tumoral , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Concentração de Íons de Hidrogênio , Células A549 , Liberação Controlada de Fármacos , Camundongos Nus , Apoptose/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Hemólise/efeitos dos fármacos
2.
Nat Commun ; 15(1): 2270, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491004

RESUMO

The success of macrophage-based adoptive cell therapy is largely constrained by poor polarization from alternatively activated (M2-like) to classically activated (M1-like) phenotype in the immunosuppressive tumor microenvironment (TME). Here, we show that the engineered macrophage (eMac) with a heat-inducible genetic switch can induce both self-polarization of adoptively transferred eMac and re-polarization of tumour-associated macrophages in response to mild temperature elevation in a mouse model. The locoregional production of proinflammatory cytokines by eMac in the TME dose not only induces the strong polarization of macrophages into a classically activated phenotype, but also ensures that the side effects typical for systemically administrate proinflammatory cytokines are avoided. We also present a wearable warming device which is adaptable for human patients and can be remotely controlled by a smartphone. In summary, our work represents a safe and efficient adoptive transfer immunotherapy method with potential for human translation.


Assuntos
Neoplasias , Microambiente Tumoral , Camundongos , Animais , Humanos , Temperatura Alta , Macrófagos , Citocinas/farmacologia , Neoplasias/terapia , Imunoterapia
3.
Angew Chem Int Ed Engl ; 63(14): e202316323, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38317057

RESUMO

We synthesize supramolecular poly(disulfide) (CPS) containing covalently attached cucurbit[7]uril (CB[7]), which is exploited not only as a carrier to deliver plasmid DNA encoding destabilized Cas9 (dsCas9), but also as a host to include trimethoprim (TMP) by CB[7] moieties through the supramolecular complexation to form TMP@CPS/dsCas9. Once the plasmid is transfected into tumor cells by CPS, the presence of polyamines can competitively trigger the decomplexation of TMP@CPS, thereby displacing and releasing TMP from CB[7] to stabilize dsCas9 that can target and edit the genomic locus of PLK1 to inhibit the growth of tumor cells. Following the systemic administration of TMP@CPS/dsCas9 decorated with hyaluronic acid (HA), tumor-specific editing of PLK1 is detected due to the elevated polyamines in tumor microenvironment, greatly minimizing off-target editing in healthy tissues and non-targeted organs. As the metabolism of polyamines is dysregulated in a wide range of disorders, this study offers a supramolecular approach to precisely control CRISPR/Cas9 functions under particular pathological contexts.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Sistemas CRISPR-Cas/genética , Plasmídeos , DNA , Poliaminas
4.
J Environ Manage ; 352: 120028, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38219668

RESUMO

One of the key issues in manure management of livestock production is to reduce greenhouse gas (GHG) and air pollutant emissions, which lead to significant environmental footprint and human/animal health threats. This study provides a review of potentially efficacious technologies and management strategies that reduce GHG and air pollutant emissions during the three key stages of manure management in livestock production, i.e., animal housing, manure storage and treatment, and manure application. Several effective mitigation technologies and practices for each manure management stage are identified and analyzed in detail, including feeding formulation adjustment, frequent manure removal and air scrubber during animal housing stage; solid-liquid separation, manure covers for storage, acidification, anaerobic digestion and composting during manure storage and treatment stage; land application techniques at appropriate timing during manure application stage. The results indicated several promising approaches to reduce multiple gas emissions from the entire manure management. Removing manure 2-3 times per week or every day during animal housing stage is an effective and simple way to reduce GHG and air pollutant emissions. Acidification during manure storage and treatment stage can reduce ammonia and methane emissions by 33%-93% and 67%-87%, respectively and proper acid, such as lactic acid can also reduce nitrous oxide emission by about 90%. Shallow injection of manure for field application has the best performance in reducing ammonia emission by 62%-70% but increase nitrous oxide emission. The possible trade-off brings insight to the prioritization of targeted gas emissions for the researchers, stakeholders and policymakers, and also highlights the importance of assessing the mitigation technologies across the entire manure management chain. Implementing a combination of the management strategies needs comprehensive considerations about mitigation efficiency, technical feasibility, local regulations, climate condition, scalability and cost-effectiveness.


Assuntos
Poluentes Atmosféricos , Gases de Efeito Estufa , Animais , Humanos , Poluentes Atmosféricos/análise , Gado , Amônia , Esterco/análise , Óxido Nitroso/análise , Efeito Estufa , Metano/análise
5.
Molecules ; 28(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836681

RESUMO

Six new tirucallane-type triterpenoids, named munropenes A-F (1-6), were extracted from the whole plants of Munronia pinnata using a water extraction method. Their chemical structures were determined based on detailed spectroscopic data. The relative configurations of the acyclic structures at C-17 of munropenes A-F (1-6) were established using carbon-proton spin-coupling constants (2,3JC,H) and inter-proton spin-coupling constants (3JH,H). Furthermore, the absolute configurations of munropenes A-F (1-6) were determined through high-performance liquid chromatography (HPLC), single-crystal X-ray diffraction, and electronic circular dichroism (ECD) analyses. The antiproliferative effects of munropenes A-F were evaluated in five tumor cell lines: HCT116, A549, HepG2, MCF7, and MDAMB. Munropenes A, B, D, and F (1, 2, 4, and 6) inhibited proliferation in the HCT116 cell line with IC50 values of 40.90, 19.13, 17.66, and 32.62 µM, respectively.


Assuntos
Prótons , Triterpenos , Humanos , Triterpenos/farmacologia , Triterpenos/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Células HCT116 , Estrutura Molecular
6.
Fitoterapia ; 168: 105539, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37178810

RESUMO

Phytochemical study on the whole plants of a Gentianaceous medicinal plant, Canscora lucidissima, gave one new acylated iridoid glucoside, canscorin A (1), and two new xanthone glycosides (2 and 3) together with 17 known compounds including five xanthones, eight xanthone glycosides, two benzophenone glucosides, caffeic acid, and loganic acid. Canscorin A (1) was assigned as a loganic acid derivative having a hydroxyterephthalic acid moiety by spectroscopic analysis together with chemical evidence, while 2 and 3 were elucidated to be a rutinosylxanthone and a glucosylxanthone, respectively. The absolute configurations of the sugar moieties of 2 and 3 were determined by HPLC analysis. The isolated compounds were evaluated for their inhibitory activities against erastin-induced ferroptosis on human hepatoma Hep3B cells and LPS-stimulated IL-1ß production from murine microglial cells.


Assuntos
Ferroptose , Gentianaceae , Xantonas , Camundongos , Humanos , Animais , Glucosídeos Iridoides , Estrutura Molecular , Glicosídeos/farmacologia , Glicosídeos/química , Xantonas/farmacologia
7.
Nat Commun ; 14(1): 2474, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120596

RESUMO

The ribosome-associated quality-control (RQC) pathway degrades aberrant nascent polypeptides arising from ribosome stalling during translation. In mammals, the E3 ligase Pirh2 mediates the degradation of aberrant nascent polypeptides by targeting the C-terminal polyalanine degrons (polyAla/C-degrons). Here, we present the crystal structure of Pirh2 bound to the polyAla/C-degron, which shows that the N-terminal domain and the RING domain of Pirh2 form a narrow groove encapsulating the alanine residues of the polyAla/C-degron. Affinity measurements in vitro and global protein stability assays in cells further demonstrate that Pirh2 recognizes a C-terminal A/S-X-A-A motif for substrate degradation. Taken together, our study provides the molecular basis underlying polyAla/C-degron recognition by Pirh2 and expands the substrate recognition spectrum of Pirh2.


Assuntos
Mamíferos , Ubiquitina-Proteína Ligases , Animais , Ubiquitina-Proteína Ligases/metabolismo , Proteólise , Mamíferos/metabolismo
8.
Front Oncol ; 13: 1112879, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007084

RESUMO

Introduction: The leukemic cells of patients with chronic lymphocytic leukemia (CLL) are often unique, expressing remarkably similar IGHV-IGHD-IGHJ gene rearrangements, "stereotyped BCRs". The B-cell receptors (BCRs) on CLL cells are also distinctive in often deriving from autoreactive B lymphocytes, leading to the assumption of a defect in immune tolerance. Results: Using bulk and single-cell immunoglobulin heavy and light chain variable domain sequencing, we enumerated CLL stereotype-like IGHV-IGHD-IGHJ sequences (CLL-SLS) in B cells from cord blood (CB) and adult peripheral blood (PBMC) and bone marrow (BM of healthy donors. CLL-SLS were found at similar frequencies among CB, BM, and PBMC, suggesting that age does not influence CLL-SLS levels. Moreover, the frequencies of CLL-SLS did not differ among B lymphocytes in the BM at early stages of development, and only re-circulating marginal zone B cells contained significantly higher CLL-SLS frequencies than other mature B-cell subpopulations. Although we identified CLL-SLS corresponding to most of the CLL major stereotyped subsets, CLL-SLS frequencies did not correlate with those found in patients. Interestingly, in CB samples, half of the CLL-SLS identified were attributed to two IGHV-mutated subsets. We also found satellite CLL-SLS among the same normal samples, and they were also enriched in naïve B cells but unexpectedly, these were ~10-fold higher than standard CLL-SLS. In general, IGHV-mutated CLL-SLS subsets were enriched among antigen-experienced B-cell subpopulations, and IGHV-unmutated CLL-SLS were found mostly in antigen-inexperienced B cells. Nevertheless, CLL-SLS with an IGHV-mutation status matching that of CLL clones varied among the normal B-cell subpopulations, suggesting that specific CLL-SLS could originate from distinct subpopulations of normal B cells. Lastly, using single-cell DNA sequencing, we identified paired IGH and IGL rearrangements in normal B lymphocytes resembling those of stereotyped BCRs in CLL, although some differed from those in patients based on IG isotype or somatic mutation. Discussion: CLL-SLS are present in normal B-lymphocyte populations at all stages of development. Thus, despite their autoreactive profile they are not deleted by central tolerance mechanisms, possibly because the level of autoreactivity is not registered as dangerous by deletion mechanisms or because editing of L-chain variable genes occurred which our experimental approach could not identify.

9.
Chem Biodivers ; 20(4): e202300025, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36898972

RESUMO

Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns and trigger an inflammatory response via the myeloid differential factor 88 (MyD88)-dependent and toll-interleukin-1 receptor domain-containing adapter-inducing interferon-ß (TRIF)-dependent pathways. Lindenane type sesquiterpene dimers (LSDs) are characteristic metabolites of plants belonging to the genus Sarcandra (Chloranthaceae). The aim of this study was to evaluate the potential anti-inflammatory effects of the LSDs shizukaol D (1) and sarcandrolide E (2) on lipopolysaccharides (LPS)-stimulated RAW264.7 macrophages in vitro, and explore the underlying mechanisms. Both LSDs neutralized the LPS-induced morphological changes and production of nitric oxide (NO), as determined by CCK-8 assay and Griess assay, respectively. Furthermore, shizukaol D (1) and sarcandrolide E (2) downregulated interferon ß (IFNß), tumor necrosis factor α (TNFα) and interleukin-1ß (IL-1ß) mRNA levels as measured by reverse transcription polymerase chain reaction (RT-PCR), and inhibited the phosphorylation of nuclear factor kappa B p65 (p65), nuclear factor kappa-Bα (IκBα), Jun N-terminal kinase (JNK), extracellular regulated kinase (ERK), mitogen-activated protein kinase p38 (p38), MyD88, IL-1RI-associated protein kinase 1 (IRAK1), and transforming growth factor-ß-activated kinase 1 (TAK1) proteins in the Western blotting assay. In conclusion, LSDs can alleviate the inflammatory response by inhibiting the TLR/MyD88 signalling pathway.


Assuntos
Inflamação , Sesquiterpenos , Receptores Toll-Like , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Sesquiterpenos/farmacologia , Receptores Toll-Like/antagonistas & inibidores , Receptores Toll-Like/metabolismo
10.
Front Oncol ; 12: 897280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903706

RESUMO

Patients with CLL with mutated IGHV genes (M-CLL) have better outcomes than patients with unmutated IGHVs (U-CLL). Since U-CLL usually express immunoglobulins (IGs) that are more autoreactive and more effectively transduce signals to leukemic B cells, B-cell receptor (BCR) signaling is likely at the heart of the worse outcomes of CLL cases without/few IGHV mutations. A corollary of this conclusion is that M-CLL follow less aggressive clinical courses because somatic IGHV mutations have altered BCR structures and no longer bind stimulatory (auto)antigens and so cannot deliver trophic signals to leukemic B cells. However, the latter assumption has not been confirmed in a large patient cohort. We tried to address the latter by measuring the relative numbers of replacement (R) mutations that lead to non-conservative amino acid changes (Rnc) to the combined numbers of conservative (Rc) and silent (S) amino acid R mutations that likely do not or cannot change amino acids, "(S+Rc) to Rnc IGHV mutation ratio". When comparing time-to-first-treatment (TTFT) of patients with (S+Rc)/Rnc ≤ 1 and >1, TTFTs were similar, even after matching groups for equal numbers of samples and identical numbers of mutations per sample. Thus, BCR structural change might not be the main reason for better outcomes for M-CLL. Since the total number of IGHV mutations associated better with longer TTFT, better clinical courses appear due to the biologic state of a B cell having undergone many stimulatory events leading to IGHV mutations. Analyses of larger patient cohorts will be needed to definitively answer this question.

11.
Se Pu ; 40(4): 364-371, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35362684

RESUMO

Siraitia grosvenorii (Swingle) C. Jeffrey, belonging to the family Cucurbitaceae, is a natural sweetener. The roots of this plant are used in folk medicine for the treatment of rheumatoid arthritis. Cucurbitacins play an important role in the resistance of this plant to insects and adversity, and have anti-inflammatory, anti-tumor, and other biological activities. They usually exist as a variety of similar structures in Cucurbitaceae plants. Separation of a large amount of high-purity monomer compounds by the conventional separation method based on column chromatography is difficult, which limits the research and application of their activities. Therefore, we chose a new method for this separation. High-speed countercurrent chromatography (HSCCC) is a liquid-liquid chromatographic technique characterized by high recovery and reproducibility, and is considered a very effective method for the separation of natural compounds present in various plant extracts. An appropriate solvent system is the key for efficient separation, but its selection is tedious, which hampers the wider implementation of HSCCC in chemical research involving preparative separations. In this study, based on the general estimation strategy by using the TLC solvent system (GUESS), the corresponding relationship between the partition distribution coefficient (K value) and the TLC retention factor (Rf value) of the compounds was established by the partition experiment. The Rf value and separation coefficient α were calculated using the water-saturated organic phase as the expansion agent, which could minimize the number of countercurrent separation experiments required in solvent system selection. In this study, HSCCC was used to establish an efficient method for the extraction of cucurbitacins from the root extract of Siraitia grosvenorii. A fraction rich in cucurbitacins was obtained from the ethanol extract of Siraitia grosvenorii roots after separation by column chromatography on HPD-100, MCI, and C18 columns. Six types of solvent systems with different compositions were investigated using the GUESS method. The results showed that employing the solvent system of n-hexane-ethyl acetate-methanol-water (3∶7∶3∶7, v/v/v/v) to partition the cucurbitacin fraction could remove a large number of impurities. The components retained in the upper phase in the partition experiment were subsequently purified by HSCCC. The favorable solvent system for HSCCC was n-hexane-ethyl acetate-methanol-water (4∶6∶5∶5, v/v/v/v), while the upper and lower phases were selected as the stationary and mobile phases, respectively, with a flow rate of 2.0 mL/min, a rotation speed of 860 r/min, and an injected sample weight of 280 mg. Five cucurbitacin compounds were obtained by one-time separation. The weights of the five compounds were 14.73, 8.82, 30.74, 5.03, and 3.81 mg. The purities of these compounds were 97.0%, 95.4%, 96.3%, 91.6%, and 95.3%, respectively. Their structures were identified as cucurbitacin Q1, 23,24-dihydrocucurbitacin F-25-acetate, cucurbitacin B, 23,24-dihydrocucurbitacin B, and dihydroisocucurbitacin B-25-acetate by1H-NMR and 13C-NMR spectroscopies, along with comparison with the literature. This study demonstrated how GUESS guidance accelerates the selection of HSCCC solvent systems, simplifies the workflow, and it provides an efficient preparative method for the separation of chemical constituents from the Siraitia grosvenorii roots, which can also be used as a new method for the large-scale preparation of cucurbitacin compounds.


Assuntos
Cucurbitaceae , Cucurbitacinas , Distribuição Contracorrente , Reprodutibilidade dos Testes , Solventes
13.
Nano Lett ; 21(22): 9761-9771, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34767372

RESUMO

Based on the high frequency of concurrent adenomatous polyposis coli (APC) and KRAS mutations and their strong cooperative interaction in human colorectal cancer (CRC) promotion, we herein develop a CRISPR-Cas9-based genome-editing nanomedicine to target both APC and KRAS mutations for the treatment of CRC. To this end, a hyaluronic acid (HA)-decorated phenylboronic dendrimer (HAPD) was designed for the targeted delivery of Cas9 ribonucleoprotein (RNP), by which both APC and KRAS genetic mutations harboring in CRC cells can be synergistically disrupted. Systemic administration of Cas9 RNP targeting APC and KRAS enabled by HAPD significantly inhibits tumor growth on xenografted and orthotopic CRC mouse models and also greatly prevents CRC-induced liver metastasis and lung metastasis. Thus, this duplex genome-editing system provides a promising gene therapy strategy for the treatment of human CRC and can be extended to other types of cancers with activated Wnt/ß-catenin and RAS/extracellular signal-regulated kinase (ERK) pathways.


Assuntos
Sistemas CRISPR-Cas , Neoplasias Colorretais , Animais , Sistemas CRISPR-Cas/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Terapia Genética , Camundongos , Nanomedicina , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Via de Sinalização Wnt
14.
Int J Mol Sci ; 22(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34445681

RESUMO

Parthenogenetic embryos have been widely studied as an effective tool related to paternal and maternal imprinting genes and reproductive problems for a long time. In this study, we established a parthenogenetic epiblast-like stem cell line through culturing parthenogenetic diploid blastocysts in a chemically defined medium containing activin A and bFGF named paAFSCs. The paAFSCs expressed pluripotent marker genes and germ-layer-related genes, as well as being alkaline-phosphatase-positive, which is similar to epiblast stem cells (EpiSCs). We previously showed that advanced embryonic stem cells (ASCs) represent hypermethylated naive pluripotent embryonic stem cells (ESCs). Here, we converted paAFSCs to ASCs by replacing bFGF with bone morphogenetic protein 4 (BMP4), CHIR99021, and leukemia inhibitory factor (LIF) in a culture medium, and we obtained parthenogenetic advanced stem cells (paASCs). The paASCs showed similar morphology with ESCs and also displayed a stronger developmental potential than paAFSCs in vivo by producing chimaeras. Our study demonstrates that maternal genes could support parthenogenetic EpiSCs derived from blastocysts and also have the potential to convert primed state paAFSCs to naive state paASCs.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Partenogênese/fisiologia , Ativinas/metabolismo , Animais , Blastocisto/metabolismo , Proteína Morfogenética Óssea 4/farmacologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Técnicas de Cultura Embrionária/métodos , Feminino , Fatores de Crescimento de Fibroblastos/farmacologia , Camadas Germinativas/metabolismo , Camadas Germinativas/fisiologia , Fator Inibidor de Leucemia/farmacologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos ICR , Células-Tronco Embrionárias Murinas/citologia , Partenogênese/genética , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/patologia
15.
Blood ; 138(3): 246-258, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292322

RESUMO

Most cancers become more dangerous by the outgrowth of malignant subclones with additional DNA mutations that favor proliferation or survival. Using chronic lymphocytic leukemia (CLL), a disease that exemplifies this process and is a model for neoplasms in general, we created transgenic mice overexpressing the enzyme activation-induced deaminase (AID), which has a normal function of inducing DNA mutations in B lymphocytes. AID not only allows normal B lymphocytes to develop more effective immunoglobulin-mediated immunity, but is also able to mutate nonimmunoglobulin genes, predisposing to cancer. In CLL, AID expression correlates with poor prognosis, suggesting a role for this enzyme in disease progression. Nevertheless, direct experimental evidence identifying the specific genes that are mutated by AID and indicating that those genes are associated with disease progression is not available. To address this point, we overexpressed Aicda in a murine model of CLL (Eµ-TCL1). Analyses of TCL1/AID mice demonstrate a role for AID in disease kinetics, CLL cell proliferation, and the development of cancer-related target mutations with canonical AID signatures in nonimmunoglobulin genes. Notably, our mouse models can accumulate mutations in the same genes that are mutated in human cancers. Moreover, some of these mutations occur at homologous positions, leading to identical or chemically similar amino acid substitutions as in human CLL and lymphoma. Together, these findings support a direct link between aberrant AID activity and CLL driver mutations that are then selected for their oncogenic effects, whereby AID promotes aggressiveness in CLL and other B-cell neoplasms.


Assuntos
Citidina Desaminase/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/genética , Regulação para Cima , Animais , Modelos Animais de Doenças , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação
16.
Leukemia ; 35(11): 3163-3175, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33935280

RESUMO

Cancer pathogenesis involves the interplay of tumor- and microenvironment-derived stimuli. Here we focused on the influence of an immunomodulatory cell type, myeloid-derived suppressor cells (MDSCs), and their lineage-related subtypes on autologous T lymphocytes. Although MDSCs as a group correlated with an immunosuppressive Th repertoire and worse clinical course, MDSC subtypes (polymorphonuclear, PMN-MDSC, and monocytic, M-MDSCs) were often functionally discordant. In vivo, PMN-MDSCs existed in higher numbers, correlated with different Th-subsets, and more strongly associated with poor clinical course than M-MDSCs. In vitro, PMN-MDSCs were more efficient at blocking T-cell growth and promoted Th17 differentiation. Conversely, in vitro M-MDSCs varied in their ability to suppress T-cell proliferation, due to the action of TNFα, and promoted a more immunostimulatory Th compartment. Ibrutinib therapy impacted MDSCs differentially as well, since after initiating therapy, PMN-MDSC numbers progressively declined, whereas M-MDSC numbers were unaffected, leading to a set of less immunosuppressive Th cells. Consistent with this, clinical improvement based on decreasing CLL-cell numbers correlated with the decrease in PMN-MDSCs. Collectively, the data support a balance between PMN-MDSC and M-MDSC numbers and function influencing CLL disease course.


Assuntos
Leucemia Linfocítica Crônica de Células B/imunologia , Ativação Linfocitária/imunologia , Células Supressoras Mieloides/imunologia , Linfócitos T/imunologia , Células Th1/imunologia , Células Th2/imunologia , Microambiente Tumoral , Estudos de Casos e Controles , Diferenciação Celular , Proliferação de Células , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Monócitos/imunologia , Células Supressoras Mieloides/classificação , Células Supressoras Mieloides/patologia
17.
Leukemia ; 35(4): 1037-1052, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33504942

RESUMO

Progression of chronic lymphocytic leukemia (CLL) results from the expansion of a small fraction of proliferating leukemic B cells. When comparing the global gene expression of recently divided CLL cells with that of previously divided cells, we found higher levels of genes involved in regulating gene expression. One of these was the oncogene Musashi 2 (MSI2), an RNA-binding protein that induces or represses translation. While there is an established role for MSI2 in normal and malignant stem cells, much less is known about its expression and role in CLL. Here we report for the first time ex vivo and in vitro experiments that MSI2 protein levels are higher in dividing and recently divided leukemic cells and that downregulating MSI2 expression or blocking its function eliminates primary human and murine CLL and mature myeloid cells. Notably, mature T cells and hematopoietic stem and progenitor cells are not affected. We also confirm that higher MSI2 levels correlate with poor outcome markers, shorter time-to-first-treatment, and overall survival. Thus, our data highlight an important role for MSI2 in CLL-cell survival and proliferation and associate MSI2 with poor prognosis in CLL patients. Collectively, these findings pinpoint MSI2 as a potentially valuable therapeutic target in CLL.


Assuntos
Biomarcadores Tumorais , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Ligação a RNA/genética , Animais , Antineoplásicos , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos , Terapia de Alvo Molecular , Prognóstico , RNA Interferente Pequeno , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Blood ; 137(10): 1365-1376, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32992344

RESUMO

Chronic lymphocytic leukemia (CLL) is characterized by the existence of subsets of patients with (quasi)identical, stereotyped B-cell receptor (BcR) immunoglobulins. Patients in certain major stereotyped subsets often display remarkably consistent clinicobiological profiles, suggesting that the study of BcR immunoglobulin stereotypy in CLL has important implications for understanding disease pathophysiology and refining clinical decision-making. Nevertheless, several issues remain open, especially pertaining to the actual frequency of BcR immunoglobulin stereotypy and major subsets, as well as the existence of higher-order connections between individual subsets. To address these issues, we investigated clonotypic IGHV-IGHD-IGHJ gene rearrangements in a series of 29 856 patients with CLL, by far the largest series worldwide. We report that the stereotyped fraction of CLL peaks at 41% of the entire cohort and that all 19 previously identified major subsets retained their relative size and ranking, while 10 new ones emerged; overall, major stereotyped subsets had a cumulative frequency of 13.5%. Higher-level relationships were evident between subsets, particularly for major stereotyped subsets with unmutated IGHV genes (U-CLL), for which close relations with other subsets, termed "satellites," were identified. Satellite subsets accounted for 3% of the entire cohort. These results confirm our previous notion that major subsets can be robustly identified and are consistent in relative size, hence representing distinct disease variants amenable to compartmentalized research with the potential of overcoming the pronounced heterogeneity of CLL. Furthermore, the existence of satellite subsets reveals a novel aspect of repertoire restriction with implications for refined molecular classification of CLL.


Assuntos
Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Frequência do Gene , Rearranjo Gênico , Humanos , Hipermutação Somática de Imunoglobulina
19.
Biosci Rep ; 40(9)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32955094

RESUMO

BACKGROUND: Keratinocyte migration is essential for skin wound healing and recent studies demonstrated that microRNAs (miRNAs) are involved in the differentiation, migration and apoptosis in keratinocytes. However, the function of miR-26a in wound healing remains to be largely explored. METHODS: Northern blot and quantitative reverse transcriptase PCR (qRT-PCR) were used to detect the miR-26a expression and Western blot was used to detect integrin α-5 (ITGA5), phosphatidylinositol-3-kinase (PI3K), p-PI3K, protein kinase B (AKT) and p-AKT protein expression in immortalized human keratinocyte cell line HaCaT and normal human epidermal keratinocytes (NHEK) after 2 ng/ml transforming growth factor-ß1 (TGF-ß1) treatment for 0, 6, 12 and 24 h. Transwell assay and Wound healing assay were introduced to measure the cell migration of HaCaT cells. TargetScan online database, luciferase reporter assay and RNA immunoprecipitation (RIP) were employed to confirm the relationship between miR-26a and ITGA5. RESULTS: The RNA expression of miR-26a was down-regulated and ITGA5 protein expression was up-regulated by TGF-ß1 treatment in HaCaT and NHEK cells in a time-dependent manner. MiR-26a overexpression inhibited the migration of HaCaT cells induced by TGF-ß1 while miR-26a inhibitor enhanced the migration. ITGA5 was a downstream target mRNA and regulated by miR-26a. ITGA5 overexpression reversed the inhibitory effect of miR-26a on migration in HaCaT, while ITGA5 knockdown attenuated the stimulative effect of miR-26a inhibitor in HaCaT via PI3K/AKT signaling pathway. CONCLUSION: MiR-26a overexpression inhibited TGF-ß1 induced HaCaT cells migration via down-regulating ITGA5 through activating the PI3K/AKT signaling pathway.


Assuntos
Integrinas/genética , Queratinócitos/fisiologia , MicroRNAs/metabolismo , Cicatrização/genética , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Integrinas/metabolismo , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima , Cicatrização/efeitos dos fármacos
20.
FEBS J ; 287(21): 4696-4709, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32129936

RESUMO

Anoikis (detachment-induced cell death) is a specific type of programmed cell death which occurs in response to the loss of the correct extracellular matrix connections. Anoikis resistance is an important mechanism in cancer invasiveness and metastatic behavior. Autophagy, on the other hand, involves the degradation of damaged organelles and the recycling of misfolded proteins and intracellular components. However, the intersection of these two cellular responses in lung cancer cells has not been extensively studied. Here, we identified that upon matrix deprivation, the lymphocyte lineage-specific Ets transcription factor SPIB was activated and directly enhanced SNAP47 transcription in certain lung cancer cells. Loss of attachment-induced autophagy significantly increased anoikis resistance by SPIB activation. Consistent with this function, SPIB depletion by short hairpin RNA abrogated SNAP47 transcriptional activation upon matrix deprivation. Therefore, these data delineate an important role of SPIB in autophagy-mediated anoikis resistance in lung cancer cells. Accordingly, these findings suggest that manipulating SPIB-regulated pathways in vivo and evaluating the impact of anoikis resistance warrant further investigation. DATABASE: RNA sequencing and ChIP sequencing data are available in Gene Expression Omnibus database under the accession numbers GSE106592 and GSE125561, respectively.


Assuntos
Anoikis/genética , Autofagia/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Lisossomos/metabolismo , Fatores de Transcrição/genética , Células A549 , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica/métodos , Células HEK293 , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/ultraestrutura , Lisossomos/ultraestrutura , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Fatores de Transcrição/metabolismo
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