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1.
Cell ; 171(4): 849-864.e25, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29100074

RESUMO

Angiogenin (ANG) is a secreted ribonuclease (RNase) with cell-type- and context-specific roles in growth, survival, and regeneration. Although these functions require receptor-mediated endocytosis and appropriate subcellular localization, the identity of the cell surface receptor remains undefined. Here, we show that plexin-B2 (PLXNB2) is the functional receptor for ANG in endothelial, cancer, neuronal, and normal hematopoietic and leukemic stem and progenitor cells. Mechanistically, PLXNB2 mediates intracellular RNA processing that contribute to cell growth, survival, and regenerative capabilities of ANG. Antibodies generated against the ANG-binding site on PLXNB2 restricts ANG activity in vitro and in vivo, resulting in inhibition of established xenograft tumors, ANG-induced neurogenesis and neuroprotection, levels of pro-self-renewal transcripts in hematopoietic and patient-derived leukemic stem and progenitor cells, and reduced progression of leukemia in vivo. PLXNB2 is therefore required for the physiological and pathological functions of ANG and has significant therapeutic potential in solid and hematopoietic cancers and neurodegenerative diseases.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Feminino , Glioblastoma/metabolismo , Glioblastoma/patologia , Células-Tronco Hematopoéticas/metabolismo , Xenoenxertos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neurogênese , Ribonuclease Pancreático/química
2.
Cell ; 166(4): 894-906, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27518564

RESUMO

Regulation of stem and progenitor cell populations is critical in the development, maintenance, and regeneration of tissues. Here, we define a novel mechanism by which a niche-secreted RNase, angiogenin (ANG), distinctively alters the functional characteristics of primitive hematopoietic stem/progenitor cells (HSPCs) compared with lineage-committed myeloid-restricted progenitor (MyePro) cells. Specifically, ANG reduces the proliferative capacity of HSPC while simultaneously increasing proliferation of MyePro cells. Mechanistically, ANG induces cell-type-specific RNA-processing events: tRNA-derived stress-induced small RNA (tiRNA) generation in HSPCs and rRNA induction in MyePro cells, leading to respective reduction and increase in protein synthesis. Recombinant ANG protein improves survival of irradiated animals and enhances hematopoietic regeneration of mouse and human HSPCs in transplantation. Thus, ANG plays a non-cell-autonomous role in regulation of hematopoiesis by simultaneously preserving HSPC stemness and promoting MyePro proliferation. These cell-type-specific functions of ANG suggest considerable therapeutic potential.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Proliferação de Células , Hematopoese , Células-Tronco Hematopoéticas/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , RNA de Transferência/metabolismo , RNA não Traduzido/metabolismo
3.
Nature ; 629(8011): 481-488, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38632411

RESUMO

The human calcium-sensing receptor (CaSR) detects fluctuations in the extracellular Ca2+ concentration and maintains Ca2+ homeostasis1,2. It also mediates diverse cellular processes not associated with Ca2+ balance3-5. The functional pleiotropy of CaSR arises in part from its ability to signal through several G-protein subtypes6. We determined structures of CaSR in complex with G proteins from three different subfamilies: Gq, Gi and Gs. We found that the homodimeric CaSR of each complex couples to a single G protein through a common mode. This involves the C-terminal helix of each Gα subunit binding to a shallow pocket that is formed in one CaSR subunit by all three intracellular loops (ICL1-ICL3), an extended transmembrane helix 3 and an ordered C-terminal region. G-protein binding expands the transmembrane dimer interface, which is further stabilized by phospholipid. The restraint imposed by the receptor dimer, in combination with ICL2, enables G-protein activation by facilitating conformational transition of Gα. We identified a single Gα residue that determines Gq and Gs versus Gi selectivity. The length and flexibility of ICL2 allows CaSR to bind all three Gα subtypes, thereby conferring capacity for promiscuous G-protein coupling.


Assuntos
Proteínas Heterotriméricas de Ligação ao GTP , Receptores de Detecção de Cálcio , Humanos , Cálcio/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/química , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/química , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/química , Modelos Moleculares , Ligação Proteica , Multimerização Proteica , Receptores de Detecção de Cálcio/metabolismo , Receptores de Detecção de Cálcio/química , Proteínas Heterotriméricas de Ligação ao GTP/química , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Sítios de Ligação , Estrutura Secundária de Proteína , Especificidade por Substrato
4.
EMBO J ; 42(10): e112408, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37009655

RESUMO

The molecular mechanisms underlying estrogen receptor (ER)-positive breast carcinogenesis and endocrine therapy resistance remain incompletely understood. Here, we report that circPVT1, a circular RNA generated from the lncRNA PVT1, is highly expressed in ERα-positive breast cancer cell lines and tumor samples and is functionally important in promoting ERα-positive breast tumorigenesis and endocrine therapy resistance. CircPVT1 acts as a competing endogenous RNA (ceRNA) to sponge miR-181a-2-3p, promoting the expression of ESR1 and downstream ERα-target genes and breast cancer cell growth. Furthermore, circPVT1 directly interacts with MAVS protein to disrupt the RIGI-MAVS complex formation, inhibiting type I interferon (IFN) signaling pathway and anti-tumor immunity. Anti-sense oligonucleotide (ASO)-targeting circPVT1 inhibits ERα-positive breast cancer cell and tumor growth, re-sensitizing tamoxifen-resistant ERα-positive breast cancer cells to tamoxifen treatment. Taken together, our data demonstrated that circPVT1 can work through both ceRNA and protein scaffolding mechanisms to promote cancer. Thus, circPVT1 may serve as a diagnostic biomarker and therapeutic target for ERα-positive breast cancer in the clinic.


Assuntos
Neoplasias da Mama , RNA Circular , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Regulação Neoplásica da Expressão Gênica , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico , RNA Circular/genética , RNA Circular/metabolismo
5.
Nucleic Acids Res ; 52(11): 6220-6233, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38613396

RESUMO

Mediator is a well-known transcriptional co-regulator and serves as an adaptor between gene-specific regulatory proteins and RNA polymerase II. Studies on the chromatin-bound form of Mediator revealed interactions with additional protein complexes involved in various transcription-related processes, such as the Lsm2-8 complex that is part of the spliceosomal U6 small nuclear ribonucleoprotein complex. Here, we employ Chromatin Immunoprecipitation sequencing (ChIP-seq) of chromatin associated with the Lsm3 protein and the Med1 or Med15 Mediator subunits. We identify 86 genes co-occupied by both Lsm3 and Mediator, of which 73 were intron-containing ribosomal protein genes. In logarithmically growing cells, Mediator primarily binds to their promoter regions but also shows a second, less pronounced occupancy at their 3'-exons. During the late exponential phase, we observe a near-complete transition of Mediator from these promoters to a position in their 3'-ends, overlapping the Lsm3 binding sites ∼250 bp downstream of their last intron-exon boundaries. Using an unbiased RNA sequencing approach, we show that transition of Mediator from promoters to the last exon of these genes correlates to reduction of both their messenger RNA levels and splicing ratios, indicating that the Mediator and Lsm complexes cooperate to control growth-regulated expression of intron-containing ribosomal protein genes at the levels of transcription and splicing.


Assuntos
Íntrons , Complexo Mediador , Regiões Promotoras Genéticas , Proteínas Ribossômicas , Proteínas de Saccharomyces cerevisiae , Sítios de Ligação , Regulação Fúngica da Expressão Gênica , Íntrons/genética , Complexo Mediador/metabolismo , Complexo Mediador/genética , Ligação Proteica , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
6.
Circulation ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841852

RESUMO

BACKGROUND: Dilated cardiomyopathy is characterized by left ventricular dilation and continuous systolic dysfunction. Mitochondrial impairment is critical in dilated cardiomyopathy; however, the underlying mechanisms remain unclear. Here, we explored the cardioprotective role of a heart-enriched long noncoding RNA, the dilated cardiomyopathy repressive transcript (DCRT), in maintaining mitochondrial function. METHODS: The DCRT knockout (DCRT-/-) mice and DCRT knockout cells were developed using CRISPR-Cas9 technology. Cardiac-specific DCRT transgenic mice were generated using α-myosin heavy chain promoter. Chromatin coimmunoprecipitation, RNA immunoprecipitation, Western blot, and isoform sequencing were performed to investigate the underlying mechanisms. RESULTS: We found that the long noncoding RNA DCRT was highly enriched in the normal heart tissues and that its expression was significantly downregulated in the myocardium of patients with dilated cardiomyopathy. DCRT-/- mice spontaneously developed cardiac dysfunction and enlargement with mitochondrial impairment. DCRT transgene or overexpression with the recombinant adeno-associated virus system in mice attenuated cardiac dysfunction induced by transverse aortic constriction treatment. Mechanistically, DCRT inhibited the third exon skipping of NDUFS2 (NADH dehydrogenase ubiquinone iron-sulfur protein 2) by directly binding to PTBP1 (polypyrimidine tract binding protein 1) in the nucleus of cardiomyocytes. Skipping of the third exon of NDUFS2 induced mitochondrial dysfunction by competitively inhibiting mitochondrial complex I activity and binding to PRDX5 (peroxiredoxin 5) and suppressing its antioxidant activity. Furthermore, coenzyme Q10 partially alleviated mitochondrial dysfunction in cardiomyocytes caused by DCRT reduction. CONCLUSIONS: Our study revealed that the loss of DCRT contributed to PTBP1-mediated exon skipping of NDUFS2, thereby inducing cardiac mitochondrial dysfunction during dilated cardiomyopathy development, which could be partially treated with coenzyme Q10 supplementation.

7.
Mol Ther ; 32(5): 1578-1594, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38475992

RESUMO

Heart failure (HF) is manifested by transcriptional and posttranscriptional reprogramming of critical genes. Multiple studies have revealed that microRNAs could translocate into subcellular organelles such as the nucleus to modify gene expression. However, the functional property of subcellular Argonaute2 (AGO2), the core member of the microRNA machinery, has remained elusive in HF. AGO2 was found to be localized in both the cytoplasm and nucleus of cardiomyocytes, and robustly increased in the failing hearts of patients and animal models. We demonstrated that nuclear AGO2 rather than cytosolic AGO2 overexpression by recombinant adeno-associated virus (serotype 9) with cardiomyocyte-specific troponin T promoter exacerbated the cardiac dysfunction in transverse aortic constriction (TAC)-operated mice. Mechanistically, nuclear AGO2 activates the transcription of ANKRD1, encoding ankyrin repeat domain-containing protein 1 (ANKRD1), which also has a dual function in the cytoplasm as part of the I-band of the sarcomere and in the nucleus as a transcriptional cofactor. Overexpression of nuclear ANKRD1 recaptured some key features of cardiac remodeling by inducing pathological MYH7 activation, whereas cytosolic ANKRD1 seemed cardioprotective. For clinical practice, we found ivermectin, an antiparasite drug, and ANPep, an ANKRD1 nuclear location signal mimetic peptide, were able to prevent ANKRD1 nuclear import, resulting in the improvement of cardiac performance in TAC-induced HF.


Assuntos
Proteínas Argonautas , Modelos Animais de Doenças , Insuficiência Cardíaca , Miócitos Cardíacos , Proteínas Repressoras , Animais , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Camundongos , Humanos , Proteínas Argonautas/metabolismo , Proteínas Argonautas/genética , Miócitos Cardíacos/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Remodelação Ventricular , Núcleo Celular/metabolismo , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Regulação da Expressão Gênica , Masculino , Dependovirus/genética , Transcrição Gênica
8.
Cell Mol Life Sci ; 81(1): 121, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457049

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent gastrointestinal malignancies with high mortality worldwide. Emerging evidence indicates that long noncoding RNAs (lncRNAs) are involved in human cancers, including ESCC. However, the detailed mechanisms of lncRNAs in the regulation of ESCC progression remain incompletely understood. LUESCC was upregulated in ESCC tissues compared with adjacent normal tissues, which was associated with gender, deep invasion, lymph node metastasis, and poor prognosis of ESCC patients. LUESCC was mainly localized in the cytoplasm of ESCC cells. Knockdown of LUESCC inhibited cell proliferation, colony formation, migration, and invasion in vitro and suppressed tumor growth in vivo. Mechanistic investigation indicated that LUESCC functions as a ceRNA by sponging miR-6785-5p to enhance NRSN2 expression, which is critical for the malignant behaviors of ESCC. Furthermore, ASO targeting LUESCC substantially suppressed ESCC both in vitro and in vivo. Collectively, these data demonstrate that LUESCC may exerts its oncogenic role by sponging miR-6785-5p to promote NRSN2 expression in ESCC, providing a potential diagnostic marker and therapeutic target for ESCC patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , RNA Longo não Codificante , Humanos , Linhagem Celular Tumoral , Progressão da Doença , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
9.
Proc Natl Acad Sci U S A ; 119(34): e2200753119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35969736

RESUMO

Jumonji C-domain-containing protein 6 (JMJD6), an iron (Fe2+) and α-ketoglutarate (α-KG)-dependent oxygenase, is expressed at high levels, correlated with poor prognosis, and considered as a therapeutic target in multiple cancer types. However, specific JMJD6 inhibitors that are potent in suppressing tumorigenesis have not been reported so far. We herein report that iJMJD6, a specific small-molecule inhibitor of JMJD6 with favorable physiochemical properties, inhibits the enzymatic activity of JMJD6 protein both in vitro and in cultured cells. iJMJD6 is effective in suppressing cell proliferation, migration, and invasion in multiple types of cancer cells in a JMJD6-dependent manner, while it exhibits minimal toxicity in normal cells. Mechanistically, iJMJD6 represses the expression of oncogenes, including Myc and CCND1, in accordance with JMJD6 function in promoting the transcription of these genes. iJMJD6 exhibits suitable pharmacokinetic properties and suppresses tumor growth in multiple cancer cell line- and patient-derived xenograft models safely. Furthermore, combination therapy with iJMJD6 and BET protein inhibitor (BETi) JQ1 or estrogen receptor antagonist fulvestrant exhibits synergistic effects in suppressing tumor growth. Taken together, we demonstrate that inhibition of JMJD6 enzymatic activity by using iJMJD6 is effective in suppressing oncogene expression and cancer development, providing a therapeutic avenue for treating cancers that are dependent on JMJD6 in the clinic.


Assuntos
Antineoplásicos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Neoplasias , Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , Humanos , Neoplasias/tratamento farmacológico
10.
EMBO J ; 39(13): e103325, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32510170

RESUMO

Communication between myeloid cells and epithelium plays critical role in maintaining intestinal epithelial barrier integrity. Myeloid cells interact with intestinal epithelial cells (IECs) by producing various mediators; however, the molecules mediating their crosstalk remain incompletely understood. Here, we report that deficiency of angiogenin (Ang) in mouse myeloid cells caused impairment of epithelial barrier integrity, leading to high susceptibility to DSS-induced colitis. Mechanistically, myeloid cell-derived angiogenin promoted IEC survival and proliferation through plexin-B2-mediated production of tRNA-derived stress-induced small RNA (tiRNA) and transcription of ribosomal RNA (rRNA), respectively. Moreover, treatment with recombinant angiogenin significantly attenuated the severity of experimental colitis. In human samples, the expression of angiogenin was significantly down-regulated in patients with inflammatory bowel disease (IBD). Collectively, we identified, for the first time to our knowledge, a novel mediator of myeloid cell-IEC crosstalk in maintaining epithelial barrier integrity, suggesting that angiogenin may serve as a new preventive agent and therapeutic target for IBD.


Assuntos
Mucosa Intestinal/metabolismo , Células Mieloides/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ribonuclease Pancreático/metabolismo , Transdução de Sinais , Animais , Comunicação Celular/genética , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Sulfato de Dextrana/toxicidade , Humanos , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Células Mieloides/patologia , Proteínas do Tecido Nervoso/genética , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Ribonuclease Pancreático/genética
11.
Small ; 20(5): e2303778, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37752783

RESUMO

Cellulose nanocrystal (CNC) is a renewable resource derived from lignocellulosic materials, known for its optical permeability, biocompatibility, and unique self-assembly properties. Recent years have seen great progresses in cellulose nanocrystal-based chiral photonic materials. However, due to its inherent brittleness, cellulose nanocrystal shows limitations in the fields of flexible materials, optical sensors and food freshness testing. In order to solve the above limitations, attempts have been made to improve the flexibility of cellulose nanocrystal materials without destroying their structural color. Despite these progresses, a systematic review on them is lacking. This review aims to fill this gap by providing an overview of the main strategies and the latest research findings on the flexibilization of cellulose nanocrystal-based chiral nematic film materials (FCNM). Specifically, typical substances and methods used for their preparation are summarized. Moreover, different kinds of cellulose nanocrystal-based composites are compared in terms of flexibility. Finally, potential applications and future challenges of flexible cellulose nanocrystal-based chiral nematic materials are discussed, inspiring further research in this field.

12.
Pharmacol Res ; 199: 106990, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37984506

RESUMO

Resistance to temozolomide (TMZ), the frontline chemotherapeutic agent for glioblastoma (GBM), has emerged as a formidable obstacle, underscoring the imperative to identify alternative therapeutic strategies to improve patient outcomes. In this study, we comprehensively evaluated a novel agent, O6-methyl-2'-deoxyguanosine-5'-triphosphate (O6-methyl-dGTP) for its anti-GBM activity both in vitro and in vivo. Notably, O6-methyl-dGTP exhibited pronounced cytotoxicity against GBM cells, including those resistant to TMZ and overexpressing O6-methylguanine-DNA methyltransferase (MGMT). Mechanistic investigations revealed that O6-methyl-dGTP could be incorporated into genomic DNA, disrupting nucleotide pools balance, and inducing replication stress, resulting in S-phase arrest and DNA damage. The compound exerted its anti-tumor properties through the activation of AIF-mediated apoptosis and the parthanatos pathway. In vivo studies using U251 and Ln229 cell xenografts supported the robust tumor-inhibitory capacity of O6-methyl-dGTP. In an orthotopic transplantation model with U87MG cells, O6-methyl-dGTP showcased marginally superior tumor-suppressive activity compared to TMZ. In summary, our research, for the first time, underscores the potential of O6-methyl-dGTP as an effective candidate against GBM, laying a robust scientific groundwork for its potential clinical adoption in GBM treatment regimens.


Assuntos
Glioblastoma , Polifosfatos , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Nucleosídeos/farmacologia , Nucleosídeos/uso terapêutico , Caspases , Linhagem Celular Tumoral , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Nucleotídeos , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , O(6)-Metilguanina-DNA Metiltransferase/farmacologia , O(6)-Metilguanina-DNA Metiltransferase/uso terapêutico , Desoxiguanosina/farmacologia , Desoxiguanosina/uso terapêutico , DNA , Resistencia a Medicamentos Antineoplásicos
13.
J Org Chem ; 89(17): 12508-12513, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39135492

RESUMO

Thioesters make up an important class of bioactive compounds. Due to their chemoselectivity, they have been widely used in the synthesis of a wide range of complex bioactive molecules and natural products. At present, chemists have developed a variety of methods for the preparation of thioester compounds. However, these methods usually require the use of transition metal catalysis or harsh reaction conditions. The strategy of synthesizing thioester compounds via visible light-induced electron donor-acceptor (EDA) complex reactions avoids the problems associated with conventional methods through the development of photocatalysis. Here we report a sustainable method for thiocarbonylating aryl sulfonium salts via a visible light-induced EDA complex process without transition metals.

14.
Nucleic Acids Res ; 50(18): 10230-10248, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36124682

RESUMO

Estrogen and estrogen receptor alpha (ERα)-induced gene transcription is tightly associated with ERα-positive breast carcinogenesis. ERα-occupied enhancers, particularly super-enhancers, have been suggested to play a vital role in regulating such transcriptional events. However, the landscape of ERα-occupied super-enhancers (ERSEs) as well as key ERα-induced target genes associated with ERSEs remain to be fully characterized. Here, we defined the landscape of ERSEs in ERα-positive breast cancer cell lines, and demonstrated that bromodomain protein BRD4 is a master regulator of the transcriptional activation of ERSEs and cognate ERα target genes. RET, a member of the tyrosine protein kinase family of proteins, was identified to be a key ERα target gene of BRD4-regulated ERSEs, which, in turn, is vital for ERα-induced gene transcriptional activation and malignant phenotypes through activating the RAS/RAF/MEK2/ERK/p90RSK/ERα phosphorylation cascade. Combination therapy with BRD4 and RET inhibitors exhibited additive effects on suppressing ERα-positive breast cancer both in vitro and in vivo, comparable with that of standard endocrine therapy tamoxifen. Furthermore, combination therapy re-sensitized a tamoxifen-resistant ERα-positive breast cancer cell line to tamoxifen treatment. Taken together, our data uncovered the critical role of a super-enhancer-associated positive feedback loop constituting BRD4/ERα-RET-ERα in ERα-positive breast cancer, and suggested that targeting components in this loop would provide a new therapeutic avenue for treating ERα-positive breast cancer in the clinic.


Assuntos
Neoplasias da Mama , Receptor alfa de Estrogênio , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Estrogênios , Retroalimentação Fisiológica , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Proteínas Proto-Oncogênicas c-ret/uso terapêutico , Tamoxifeno/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
J Proteome Res ; 22(2): 368-373, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36507870

RESUMO

A tremendous amount of proteomic and phosphoproteomic data has been produced over the years with the development of mass spectrometry techniques, providing us with new opportunities to explore and understand the proteome and phosphoproteome as well as the function of proteins and protein phosphorylation sites. However, a lack of powerful tools that we can utilize to explore these valuable data limits our understanding of the proteome and phosphoproteome, particularly in diseases such as cancer. To address these unmet needs, we established CPPA (Cancer Proteome and Phosphoproteome Atlas), a web tool to mine abnormalities of the proteome and phosphoproteome in cancer based on published data sets. All analysis results are presented in CPPA with a flexible web interface to provide key customization utilities, including general analysis, differential expression profiling, statistical analysis of protein phosphorylation sites, correlation analysis, similarity analysis, survival analysis, pathological stage analysis, etc. CPPA greatly facilitates the process of data mining and therapeutic target discovery by providing a comprehensive analysis of proteomic and phosphoproteomic data in normal and tumor tissues with a simple click, which helps to unlock the precious value of mass spectrometry data by bridging the gap between raw data and experimental biologists. CPPA is currently available at https://cppa.site/cppa.


Assuntos
Neoplasias , Proteoma , Humanos , Proteoma/metabolismo , Proteômica , Mineração de Dados , Espectrometria de Massas , Fosforilação , Fosfoproteínas/metabolismo
16.
Toxicol Appl Pharmacol ; 475: 116653, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37574146

RESUMO

AIM: Ibuprofen is the most commonly used analgesic. CYP polymorphisms are mainly responsible for the differences in drug metabolism among individuals. Variations in the ability of populations to metabolize ibuprofen can lead to drug exposure events. The aim of this study was to evaluate the effects of CYP2C19 and CYP3A4 polymorphisms on ibuprofen metabolism in a Chinese population. METHODS: First, 31 CYP2C19 and 12 CYP3A4 microsomal enzymes were identified using an insect expression system. Then, variants were evaluated using a mature incubation system. Moreover, ibuprofen metabolite content was determined via ultra-performance liquid chromatography-tandem mass spectrometry analysis. Finally, kinetic parameters of CYP2C19 and CYP3A4 genotypes were determined via Michaelis-Menten curve fitting. RESULTS: Most variants exhibited significantly altered intrinsic clearance compared to the wild type. In the CYP2C19 metabolic pathway, seven variants exhibited no significant alterations in intrinsic clearance (CLint), six variants exhibited significantly high CLint (121-291%), and the remaining 15 variants exhibited substantially reduced CLint (1-71%). In the CYP3A4 metabolic pathway, CYP3A4*30 was not detected in the metabolite content due to the absence of activity, and 10 variants exhibited significantly reduced CLint. CONCLUSION: To the best of our knowledge, this is the first study to assess the kinetic characteristics of 31 CYP2C19 and 12 CYP3A4 genotypes on ibuprofen metabolism. However, further studies are needed on poor metabolizers as they are more susceptible to drug exposure. Our findings suggest that the kinetic characteristics in combination with artificial intelligence to predict the toxicity of ibuprofen and reduce any adverse drug reactions.


Assuntos
Citocromo P-450 CYP3A , Ibuprofeno , Humanos , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP2C19/genética , Inteligência Artificial , Polimorfismo Genético
17.
Nat Chem Biol ; 17(10): 1027-1036, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34552221

RESUMO

Aging is an inevitable biochemical process that adversely affects personal health and poses ever-increasing challenges to society. Recent research has revealed the crucial role of metabolism in regulating aging and longevity. During diverse metabolic processes, the host organism and their symbiotic partners-the microbiota-produce thousands of chemical products (metabolites). Emerging studies have uncovered specific metabolites that act as signaling molecules to actively regulate longevity. Here we review the latest progress in understanding the molecular mechanisms by which metabolites from the host and/or microbiota promote longevity. We also highlight state-of-the-art technologies for discovering, profiling and imaging aging- and longevity-regulating metabolites and for deciphering the molecular basis of their actions. The broad application of these technologies in aging research, together with future advances, will foster the systematic discovery of aging- and longevity-regulating metabolites and their signaling pathways. These metabolite signals should provide promising targets for developing new interventions to promote longevity and healthy aging.


Assuntos
Envelhecimento/fisiologia , Metabolismo Energético/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Animais , Biomarcadores/metabolismo , Humanos , Longevidade/fisiologia
18.
J Org Chem ; 88(20): 14351-14356, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37802501

RESUMO

Herein, we present a decarboxylative thiocarbonylation of aryl and alkenyl sulfonium salts with oxalic acid monothioethers (OAMs), which can be achieved by visible light-accelerated palladium catalysis. Sulfonium salts are widely available, and OAM is an easily accessible and stored reagent; this mild reaction method can also be used for the synthesis of different types of thioester compounds. The reaction represents a new application of visible light-accelerated palladium catalysis in catalytic decarboxylative cross-couplings.

19.
Inorg Chem ; 62(18): 7061-7068, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37121904

RESUMO

A new series of O∧C-chelate tetra-coordinated boranes with naphtha-aldehyde as the chelate backbone have been synthesized. Their photophysical and photochemical properties have been examined, which show that all of the compounds can undergo both photo and thermal transformations, generating aryl-migrated [1,2]oxaborinine derivatives as the major products. 1,3-Sigmatropic shifts and an intramolecular nucleophilic addition mechanism are proposed for the photochemical and thermal conversion pathways, respectively.

20.
Arch Toxicol ; 97(8): 2133-2142, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37209178

RESUMO

In this study, the effects of 17 CYP3A4 variants and drug-drug interactions (DDI) with its mechanism on alectinib metabolism were investigated. In vitro incubation systems of rat liver microsomes (RLM), human liver microsomes (HLM) and recombinant human CYP3A4 variants were established. The formers were used to screen potential drugs that inhibited alectinib metabolism and study the underlying mechanism, and the latter was used to determine the dynamic characteristics of CYP3A4 variants. Alectinib and its main metabolite M4 were quantitatively determined by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The results showed that compared with CYP3A4.1, only CYP3A4.29 showed higher catalytic activity, while the catalytic activity of CYP3A4.4, .7, .8, .12, .14, .16, .17, .18, .19, .20, .23, and .24 decreased significantly. Among them, the catalytic activity of CYP3A4.20 is the lowest, only 2.63% of that of CYP3A4.1. Based on the RLM incubation system in vitro, 81 drugs that may be combined with alectinib were screened, among which 18 drugs had an inhibition rate higher than 80%. In addition, nicardipine had an inhibition rate of 95.09% with a half-maximum inhibitory concentration (IC50) value of 3.54 ± 0.96 µM in RLM and 1.52 ± 0.038 µM in HLM, respectively. There was a mixture of non-competitive and anti-competitive inhibition of alectinib metabolism in both RLM and HLM. In vivo experiments of Sprague-Dawley (SD) rats, compared with the control group (30 mg/kg alectinib alone), the AUC(0-t), AUC(0-∞), Tmax and Cmax of alectinib administered in combination with 6 mg/kg nicardipine were significantly increased in the experimental group. In conclusion, the metabolism of alectinib was affected by polymorphisms of the CYP3A4 gene and nicardipine. This study provides reference data for clinical individualized administration of alectinib in the future.


Assuntos
Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450 , Ratos , Humanos , Animais , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Cromatografia Líquida , Ratos Sprague-Dawley , Nicardipino/metabolismo , Nicardipino/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem , Interações Medicamentosas , Microssomos Hepáticos/metabolismo
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