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1.
Cell ; 155(5): 1034-48, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24267889

RESUMO

LINE-1s are active human DNA parasites that are agents of genome dynamics in evolution and disease. These streamlined elements require host factors to complete their life cycles, whereas hosts have developed mechanisms to combat retrotransposition's mutagenic effects. As such, endogenous L1 expression levels are extremely low, creating a roadblock for detailed interactomic analyses. Here, we describe a system to express and purify highly active L1 RNP complexes from human suspension cell culture and characterize the copurified proteome, identifying 37 high-confidence candidate interactors. These data sets include known interactors PABPC1 and MOV10 and, with in-cell imaging studies, suggest existence of at least three types of compositionally and functionally distinct L1 RNPs. Among the findings, UPF1, a key nonsense-mediated decay factor, and PCNA, the polymerase-delta-associated sliding DNA clamp, were identified and validated. PCNA interacts with ORF2p via a PIP box motif; mechanistic studies suggest that this occurs during or immediately after target-primed reverse transcription.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Proteoma/análise , Ribonucleoproteínas/análise , Sequência de Aminoácidos , Animais , Regulação para Baixo , Genoma Humano , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Fases de Leitura Aberta , Antígeno Nuclear de Célula em Proliferação/química , Antígeno Nuclear de Célula em Proliferação/isolamento & purificação , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Helicases , Ribonucleoproteínas/isolamento & purificação , Alinhamento de Sequência , Transativadores/química , Transativadores/isolamento & purificação , Transativadores/metabolismo
2.
J Biol Chem ; 300(2): 105655, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237682

RESUMO

Endoplasmic reticulum stress is associated with insulin resistance and the development of nonalcoholic fatty liver disease. Deficiency of the endoplasmic reticulum stress response T-cell death-associated gene 51 (TDAG51) (TDAG51-/-) in mice promotes the development of high-fat diet (HFD)-induced obesity, fatty liver, and hepatic insulin resistance. However, whether this effect is due specifically to hepatic TDAG51 deficiency is unknown. Here, we report that hepatic TDAG51 protein levels are consistently reduced in multiple mouse models of liver steatosis and injury as well as in liver biopsies from patients with liver disease compared to normal controls. Delivery of a liver-specific adeno-associated virus (AAV) increased hepatic expression of a TDAG51-GFP fusion protein in WT, TDAG51-/-, and leptin-deficient (ob/ob) mice. Restoration of hepatic TDAG51 protein was sufficient to increase insulin sensitivity while reducing body weight and fatty liver in HFD fed TDAG51-/- mice and in ob/ob mice. TDAG51-/- mice expressing ectopic TDAG51 display improved Akt (Ser473) phosphorylation, post-insulin stimulation. HFD-fed TDAG51-/- mice treated with AAV-TDAG51-GFP displayed reduced lipogenic gene expression, increased beta-oxidation and lowered hepatic and serum triglycerides, findings consistent with reduced liver weight. Further, AAV-TDAG51-GFP-treated TDAG51-/- mice exhibited reduced hepatic precursor and cleaved sterol regulatory-element binding proteins (SREBP-1 and SREBP-2). In vitro studies confirmed the lipid-lowering effect of TDAG51 overexpression in oleic acid-treated Huh7 cells. These studies suggest that maintaining hepatic TDAG51 protein levels represents a viable therapeutic approach for the treatment of obesity and insulin resistance associated with nonalcoholic fatty liver disease.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Morte Celular , Dieta Hiperlipídica/efeitos adversos , Hepatócitos/metabolismo , Resistência à Insulina/fisiologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Linfócitos T/metabolismo , Masculino
3.
FASEB J ; 38(13): e23795, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38984928

RESUMO

Cystathionine beta-synthase-deficient homocystinuria (HCU) is a life-threatening disorder of sulfur metabolism. HCU can be treated by using betaine to lower tissue and plasma levels of homocysteine (Hcy). Here, we show that mice with severely elevated Hcy and potentially deficient in the folate species tetrahydrofolate (THF) exhibit a very limited response to betaine indicating that THF plays a critical role in treatment efficacy. Analysis of a mouse model of HCU revealed a 10-fold increase in hepatic levels of 5-methyl -THF and a 30-fold accumulation of formiminoglutamic acid, consistent with a paucity of THF. Neither of these metabolite accumulations were reversed or ameliorated by betaine treatment. Hepatic expression of the THF-generating enzyme dihydrofolate reductase (DHFR) was significantly repressed in HCU mice and expression was not increased by betaine treatment but appears to be sensitive to cellular redox status. Expression of the DHFR reaction partner thymidylate synthase was also repressed and metabolomic analysis detected widespread alteration of hepatic histidine and glutamine metabolism. Many individuals with HCU exhibit endothelial dysfunction. DHFR plays a key role in nitric oxide (NO) generation due to its role in regenerating oxidized tetrahydrobiopterin, and we observed a significant decrease in plasma NOx (NO2 + NO3) levels in HCU mice. Additional impairment of NO generation may also come from the HCU-mediated induction of the 20-hydroxyeicosatetraenoic acid generating cytochrome CYP4A. Collectively, our data shows that HCU induces dysfunctional one-carbon metabolism with the potential to both impair betaine treatment and contribute to multiple aspects of pathogenesis in this disease.


Assuntos
Homocistinúria , Fígado , Oxirredução , Tetra-Hidrofolato Desidrogenase , Tetra-Hidrofolatos , Animais , Homocistinúria/metabolismo , Homocistinúria/tratamento farmacológico , Homocistinúria/genética , Camundongos , Tetra-Hidrofolatos/metabolismo , Fígado/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismo , Tetra-Hidrofolato Desidrogenase/genética , Betaína/metabolismo , Betaína/farmacologia , Homocisteína/metabolismo , Camundongos Endogâmicos C57BL , Cistationina beta-Sintase/metabolismo , Cistationina beta-Sintase/genética , Carbono/metabolismo , Masculino , Ácido Fólico/metabolismo , Feminino
4.
Proc Natl Acad Sci U S A ; 119(42): e2202133119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215479

RESUMO

Unfolded protein response (UPR) is the mechanism by which cells control endoplasmic reticulum (ER) protein homeostasis. ER proteostasis is essential to adapt to cell proliferation and regeneration in development and tumorigenesis, but mechanisms linking UPR, growth control, and cancer progression remain unclear. Here, we report that the Ire1/Xbp1s pathway has surprisingly oncogenic and tumor-suppressive roles in a context-dependent manner. Activation of Ire1/Xbp1s up-regulates their downstream target Bip, which sequesters Yorkie (Yki), a Hippo pathway transducer, in the cytoplasm to restrict Yki transcriptional output. This regulation provides an endogenous defensive mechanism in organ size control, intestinal homeostasis, and regeneration. Unexpectedly, Xbp1 ablation promotes tumor overgrowth but suppresses invasiveness in a Drosophila cancer model. Mechanistically, hyperactivated Ire1/Xbp1s signaling in turn induces JNK-dependent developmental and oncogenic cell migration and epithelial-mesenchymal transition (EMT) via repression of Yki. In humans, a negative correlation between XBP1 and YAP (Yki ortholog) target gene expression specifically exists in triple-negative breast cancers (TNBCs), and those with high XBP1 or HSPA5 (Bip ortholog) expression have better clinical outcomes. In human TNBC cell lines and xenograft models, ectopic XBP1s or HSPA5 expression alleviates tumor growth but aggravates cell migration and invasion. These findings uncover a conserved crosstalk between the Ire1/Xbp1s and Hippo signaling pathways under physiological settings, as well as a crucial role of Bip-Yki interaction in tumorigenesis that is shared from Drosophila to humans.


Assuntos
Proteínas de Drosophila , Proteínas Serina-Treonina Quinases , Animais , Carcinogênese/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Retículo Endoplasmático/metabolismo , Endorribonucleases , Via de Sinalização Hippo , Humanos , Proteínas Serina-Treonina Quinases/genética , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismo
5.
Genes Dev ; 31(12): 1272-1287, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28743695

RESUMO

Hybrid seed lethality as a consequence of interspecies or interploidy hybridizations is a major mechanism of reproductive isolation in plants. This mechanism is manifested in the endosperm, a dosage-sensitive tissue supporting embryo growth. Deregulated expression of imprinted genes such as ADMETOS (ADM) underpin the interploidy hybridization barrier in Arabidopsis thaliana; however, the mechanisms of their action remained unknown. In this study, we show that ADM interacts with the AT hook domain protein AHL10 and the SET domain-containing SU(VAR)3-9 homolog SUVH9 and ectopically recruits the heterochromatic mark H3K9me2 to AT-rich transposable elements (TEs), causing deregulated expression of neighboring genes. Several hybrid incompatibility genes identified in Drosophila encode for dosage-sensitive heterochromatin-interacting proteins, which has led to the suggestion that hybrid incompatibilities evolve as a consequence of interspecies divergence of selfish DNA elements and their regulation. Our data show that imbalance of dosage-sensitive chromatin regulators underpins the barrier to interploidy hybridization in Arabidopsis, suggesting that reproductive isolation as a consequence of epigenetic regulation of TEs is a conserved feature in animals and plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Proteínas de Ciclo Celular/metabolismo , Epigênese Genética , Histona-Lisina N-Metiltransferase/farmacologia , Isolamento Reprodutivo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Regulação da Expressão Gênica de Plantas , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Hibridização Genética
6.
Cancer ; 130(6): 973-984, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38018448

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children. IKZF3 (IKAROS family zinc finger 3) is a hematopoietic-specific transcription factor, and it has been validated that it is involved in leukemia. However, the role of IKZF3 single-nucleotide polymorphisms (SNPs) remains unclear. In this case-control study, the authors investigated the association of IKZF3 SNPs with ALL in children. METHODS: Six IKZF3 reference SNPs (rs9635726, rs2060941, rs907092, rs12946510, rs1453559, and rs62066988) were genotyped in 692 patients who had ALL (cases) and in 926 controls. The associations between IKZF3 polymorphisms and ALL risk were determined using odds ratios (ORs) and 95% confidence intervals (CIs). The associations of rs9635726 and rs2060941 with the risk of ALL were further estimated by using false-positive report probability (FPRP) analysis. Functional analysis in silico was performed to evaluate the probability that rs9635726 and rs2060941 might influence the regulation of IKZF3. RESULTS: The authors observed that rs9635726C>T (adjusted OR, 1.49; 95% CI, 1.06-2.11; p = .023) and rs2060941G>T (adjusted OR, 1.51; 95% CI, 1.24-1.84; p = .001) were related to and increased risk of ALL in the recessive and dominant models, respectively. Furthermore, the associations of both rs9635726 (FPRP = .177) and rs2060941 (FPRP < .001) with ALL were noteworthy in the FPRP analysis. Functional analysis indicated that rs9635726 and rs2060941 might repress the transcription of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21. CONCLUSIONS: This study revealed that IKZF3 polymorphisms were associated with increased ALL susceptibility in children and might influence the expression of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21. IKZF3 polymorphisms were suggested as a biomarker for childhood ALL.


Assuntos
Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Estudos de Casos e Controles , Genótipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fator de Transcrição Ikaros/genética , Predisposição Genética para Doença
7.
Small ; 20(14): e2308429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988709

RESUMO

Chiral carbon nanohoops with both high fluorescence quantum yield and large luminescence dissymmetry factor are essential to the development of circularly polarized luminescence (CPL) materials. Herein, the rational design and synthesis of a series of highly fluorescent chiral carbon nanohoops TP-[8-13]CPPs via symmetry breaking with a chiral triptycene motif is reported. Theoretical calculations revealed that breaking the symmetry of nanohoops causes a unique size-dependent localization in the highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular obtitals (LUMOs) as the increasing of sizes, which is sharply different from those of [n]cycloparaphenylenes. Photophysical investigations demonstrated that TP-[n]CPPs display size-dependent emissions with high fluorescence quantum yields up to 92.9% for TP-[13]CPP, which is the highest value among the reported chiral conjugated carbon nanohoops. The high fluorescence quantum yields are presumably attributed to both the unique acyclic, and radial conjugations and high radiative transition rates, which are further supported by theoretical investigations. Chiroptical studies revealed that chiral TP-[n]CPPs exhibit bright CPL with CPL brightness up to 100.5 M-1 cm-1 for TP-[11]CPP due to the high fluorescence quantum yield. Importantly, the investigations revealed the intrigued size-dependent properties of TP-[n]CPPs with regards to (chir)optical properties, which follow a nice linear relationship versus 1/n. Such a nice linear relationship is not observed in other reported conjugated nanohoops including CPPs.

8.
Small ; : e2402190, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794869

RESUMO

SnOx has received great attention as an electrocatalyst for CO2 reduction reaction (CO2RR), however; it still suffers from low activity. Moreover, the atomic-level SnOx structure and the nature of the active sites are still ambiguous due to the dynamism of surface structure and difficulty in structure characterization under electrochemical conditions. Herein, CO2RR performance is enhanced by supporting SnO2 nanoparticles on two common supports, vulcan carbon and TiO2. Then, electrolysis of CO2 at various temperatures in a neutral electrolyte reveals that the application window for this catalyst is between 12 and 30 °C. Furthermore, this study introduces a machine learning interatomic potential method for the atomistic simulation to investigate SnO2 reduction and establish a correlation between SnOx structures and their CO2RR performance. In addition, selectivity is analyzed computationally with density functional theory simulations to identify the key differences between the binding energies of *H and *CO2 -, where both are correlated with the presence of oxygen on the nanoparticle surface. This study offers in-depth insights into the rational design and application of SnOx-based electrocatalysts for CO2RR.

10.
Chemistry ; 30(12): e202303819, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-37997515

RESUMO

We reported the synthesis of a series of structurally diverse CPL-active molecules, in which pyrene units were installed to chiral pm/po-[2,2]PCP scaffolds either with or without a triple bond spacer for pm/po-PCP-P1 and pm/po-PCP-P2, respectively. The X-ray crystallographic analyses revealed that these pyrene-based [2,2]PCP derivatives exhibited diverse structures and crystal packings in the solid phases. The pyrene-based [2,2]PCP derivatives exhibit various (chir)optical properties in organic solutions, depending on their respective structures. In a mixture of dioxane and water, pm/po-PCP-P1 emit green excimer fluorescence, whereas pm/po-PCP-P2 emit blue one. The chiroptical investigation demonstrated that Rp-pm-PCP-P1 and Rp-pm-PCP-P2 exhibited completely opposite CD and CPL signals even they possess the same chiral Rp-[2,2]PCP core. The same argument also holds for other chiral pyrene-based [2,2]PCP derivatives. The theoretical calculation revealed that these unusual phenomena were attributed to different orientation between transition electric dipole moments and the magnetic dipole moments originating from the presence or absence of a triple bond spacer. These pyrene-based [2,2]PCP derivatives display various colours and fluorescence emissions in the solid state and PMMA films, possibly due to the different packings as observed in the crystal structure. Moreover, these compounds also can interact with perylene diimide through π-π interactions, leading to near-white fluorescence.

11.
Curr Atheroscler Rep ; 26(8): 383-394, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878139

RESUMO

PURPOSE OF REVIEW: The primary objective of this review is to explore the pathophysiological roles and clinical implications of lipoprotein(a) [Lp(a)] in the context of atherosclerotic cardiovascular disease (ASCVD). We seek to understand how Lp(a) contributes to inflammation and arteriosclerosis, aiming to provide new insights into the mechanisms of ASCVD progression. RECENT FINDINGS: Recent research highlights Lp(a) as an independent risk factor for ASCVD. Studies show that Lp(a) not only promotes the inflammatory processes but also interacts with various cellular components, leading to endothelial dysfunction and smooth muscle cell proliferation. The dual role of Lp(a) in both instigating and, under certain conditions, mitigating inflammation is particularly noteworthy. This review finds that Lp(a) plays a complex role in the development of ASCVD through its involvement in inflammatory pathways. The interplay between Lp(a) levels and inflammatory responses highlights its potential as a target for therapeutic intervention. These insights could pave the way for novel approaches in managing and preventing ASCVD, urging further investigation into Lp(a) as a therapeutic target.


Assuntos
Aterosclerose , Inflamação , Lipoproteína(a) , Humanos , Lipoproteína(a)/metabolismo , Lipoproteína(a)/sangue , Aterosclerose/metabolismo , Aterosclerose/imunologia , Inflamação/metabolismo , Animais , Fatores de Risco
12.
FASEB J ; 37(10): e23143, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37698353

RESUMO

Cuproptosis, a new type of copper-induced cell death, is involved in the antitumor activity and resistance of multiple chemotherapeutic drugs. Our previous study revealed that adrenomedullin (ADM) was engaged in sunitinib resistance in clear cell renal cell carcinoma (ccRCC). However, it has yet to be investigated whether and how ADM regulates sunitinib resistance by cuproptosis. This study found that the ADM expression was elevated in sunitinib-resistant ccRCC tissues and cells. Furthermore, the upregulation of ADM significantly enhanced the chemoresistance of sunitinib compared with their respective control. Moreover, cuproptosis was involved in ADM-regulated sunitinib resistance by inhibiting mammalian ferredoxin 1 (FDX1) expression. Mechanically, the upregulated ADM activates the p38/MAPK signaling pathway to promote Forkhead box O3 (FOXO3) phosphorylation and its entry into the nucleus. Consequently, the increased FOXO3 in the nucleus inhibited FDX1 transcription and cell cuproptosis, promoting chemoresistance. Collectively, cuproptosis has a critical effector role in ccRCC progress and chemoresistance and thus is a relevant target to eradicate the cell population of sunitinib resistance.


Assuntos
Apoptose , Carcinoma de Células Renais , Carcinoma , Neoplasias Renais , Animais , Adrenomedulina/genética , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Sunitinibe/farmacologia , Cobre
13.
J Inherit Metab Dis ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840294

RESUMO

Nonketotic hyperglycinemia due to deficient glycine cleavage enzyme activity causes a severe neonatal epileptic encephalopathy. Current therapies based on mitigating glycine excess have only limited impact. An animal model with postnatal phenotyping is needed to explore new therapeutic approaches. We developed a Gldc p.Ala394Val mutant model and bred it to congenic status in two colonies on C57Bl/6J (B6) and J129X1/SvJ (J129) backgrounds. Mutant mice had reduced P-protein and enzyme activity indicating a hypomorphic mutant. Glycine levels were increased in blood and brain regions, exacerbated by dietary glycine, with higher levels in female than male J129 mice. Birth defects were more prevalent in mutant B6 than J129 mice, and hydrocephalus was more frequent in B6 (40%) compared to J129 (none). The hydrocephalus rate was increased by postnatal glycine challenge in B6 mice, more so when delivered from the first neonatal week than from the fourth. Mutant mice had reduced weight gain following weaning until the eighth postnatal week, which was exacerbated by glycine loading. The electrographic spike rate was increased in mutant mice following glycine loading, but no seizures were observed. The alpha/delta band intensity ratio was decreased in the left cortex in female J129 mice, which were less active in an open field test and explored less in a Y-maze, suggesting an encephalopathic effect. Mutant mice showed no evidence of memory dysfunction. This partial recapitulation of human symptoms and biochemistry will facilitate the evaluation of new therapeutic approaches with an early postnatal time window likely most effective.

14.
J Org Chem ; 89(1): 756-760, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38109189

RESUMO

The syntheses of hexabrominated closo-carborates decorated with different chiral Binol-derived phosphonates and their conjugate acids are described. X-ray diffraction analysis reveals a polymeric structure for the sodium salt with the anionic units connected by [B-Br-Na-O═P]+ linkages. For the acid, coordination of the proton to the phosphonate's P═O oxygen atom is assumed. The pKa value was estimated by combining experiments and computations. Application of these Brønsted acids as chiral catalysts in an imino-ene and a Mukaiyama-Mannich reaction was moderately successful.

15.
Acta Pharmacol Sin ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750075

RESUMO

Chimeric antigen receptor-expressing T (CAR-T) cells induce robust antitumor responses in patients with hematologic malignancies. However, CAR-T cells exhibit only limited efficacy against solid tumors such as hepatocellular carcinoma (HCC), partially due to their limited expansion and persistence. CD8+ T cells, as key components of the adaptive immune response, play a central role in antitumor immunity. Aerobic glycolysis is the main metabolic feature of activated CD8+ T cells. In the tumor microenvironment, however, the uptake of large amounts of glucose by tumor cells and other immunosuppressive cells can impair the activation of T cells. Only when tumor-infiltrating lymphocytes (TILs) in the tumor microenvironment have a glycolytic advantage might the effector function of T cells be activated. Glucose transporter type 1 (GLUT1) and acylglycerol kinase (AGK) can boost glycolytic metabolism and activate the effector function of CD8+ T cells, respectively. In this study, we generated GPC3-targeted CAR-T cells overexpressing GLUT1 or AGK for the treatment of HCC. GPC3-targeted CAR-T cells overexpressing GLUT1 or AGK specifically and effectively lysed GPC3-positive tumor cells in vitro in an antigen-dependent manner. Furthermore, GLUT1 or AGK overexpression protected CAR-T cells from apoptosis during repeated exposures to tumor cells. Compared with second-generation CAR-T cells, GPC3-targeted CAR-T cells overexpressing GLUT1 or AGK exhibited greater CD8+ T-cell persistence in vivo and better antitumor effects in HCC allograft mouse models. Finally, we revealed that GLUT1 or AGK maintained anti-apoptosis ability in CD8+ T cells via activation of the PI3K/Akt pathway. This finding might identify a therapeutic strategy for advanced HCC.

16.
Acta Pharmacol Sin ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605180

RESUMO

Antibody drug conjugate (ADC) therapy has become one of the most promising approaches in cancer immunotherapy. Bispecific targeting could enhance the efficacy and safety of ADC by improving its specificity, affinity and internalization. In this study we constructed a HER2/HER3-targeting bispecific ADC (BsADC) and characterized its physiochemical properties, target specificity and internalization in vitro, and assessed its anti-tumor activities in breast cancer cell lines and in animal models. The HER2/HER3-targeting BsADC had a drug to antibody ratio (DAR) of 2.89, displayed a high selectivity against the target JIMT-1 breast cancer cells in vitro, as well as a slightly higher level of internalization than HER2- or HER3-monospecific ADCs. More importantly, the bispecific ADC potently inhibited the viability of MCF7, JIMT-1, BT474, BxPC-3 and SKOV-3 cancer cells in vitro. In JIMT-1 breast cancer xenograft mice, a single injection of bispecific ADC (3 mg/kg, i.v.) significantly inhibited the tumor growth with an efficacy comparable to that caused by combined injection of HER2 and HER3-monospecific ADCs (3 mg/kg for each). Our study demonstrates that the bispecific ADC concept can be applied to development of more potent new cancer therapeutics than the monospecific ADCs.

17.
Acta Pharmacol Sin ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858494

RESUMO

T cell engaging bispecific antibodies (TCBs) have recently become significant in cancer treatment. In this study we developed MSLN490, a novel TCB designed to target mesothelin (MSLN), a glycosylphosphatidylinositol (GPI)-linked glycoprotein highly expressed in various cancers, and evaluated its efficacy against solid tumors. CDR walking and phage display techniques were used to improve affinity of the parental antibody M912, resulting in a pool of antibodies with different affinities to MSLN. From this pool, various bispecific antibodies (BsAbs) were assembled. Notably, MSLN490 with its IgG-[L]-scFv structure displayed remarkable anti-tumor activity against MSLN-expressing tumors (EC50: 0.16 pM in HT-29-hMSLN cells). Furthermore, MSLN490 remained effective even in the presence of non-membrane-anchored MSLN (soluble MSLN). Moreover, the anti-tumor activity of MSLN490 was enhanced when combined with either Atezolizumab or TAA × CD28 BsAbs. Notably, a synergistic effect was observed between MSLN490 and paclitaxel, as paclitaxel disrupted the immunosuppressive microenvironment within solid tumors, enhancing immune cells infiltration and improved anti-tumor efficacy. Overall, MSLN490 exhibits robust anti-tumor activity, resilience to soluble MSLN interference, and enhanced anti-tumor effects when combined with other therapies, offering a promising future for the treatment of a variety of solid tumors. This study provides a strong foundation for further exploration of MSLN490's clinical potential.

18.
Mol Ther ; 31(3): 701-714, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36523165

RESUMO

Limited T cell persistence restrains chimeric antigen receptor (CAR)-T cell therapy in solid tumors. To improve persistence, T cells have been engineered to secrete proinflammatory cytokines, but other possible methods have been understudied. Runx3 has been considered a master regulator of T cell development, cytotoxic T lymphocyte differentiation, and tissue-resident memory T (Trm)-cell formation. A study using a transgenic mouse model revealed that overexpression of Runx3 promoted T cell persistence in solid tumors. Here, we generated CAR-T cells overexpressing Runx3 (Run-CAR-T cells) and found that Run-CAR-T cells had long-lasting antitumor activities and achieved better tumor control than conventional CAR-T cells. We observed that more Run-CAR-T cells circulated in the peripheral blood and accumulated in tumor tissue, indicating that Runx3 coexpression improved CAR-T cell persistence in vivo. Tumor-infiltrating Run-CAR-T cells showed less cell death with enhanced proliferative and effector activities. Consistently, in vitro studies indicated that AICD was also decreased in Run-CAR-T cells via downregulation of tumor necrosis factor (TNF) secretion. Further studies revealed that Runx3 could bind to the TNF promoter and suppress its gene transcription after T cell activation. In conclusion, Runx3-armored CAR-T cells showed increased antitumor activities and could be a new modality for the treatment of solid tumors.


Assuntos
Neoplasias , Linfócitos T , Animais , Camundongos , Neoplasias/genética , Neoplasias/terapia , Imunoterapia Adotiva/métodos , Citocinas/metabolismo , Morte Celular/genética , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Mol Ther ; 31(11): 3193-3209, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37735875

RESUMO

Claudin18.2 (CLDN18.2)-specific chimeric antigen receptor (CAR-T) cells displayed limited efficacy in CLDN18.2-positive pancreatic ductal adenocarcinoma (PDAC). Strategies are needed to improve the trafficking capacity of CLDN18.2-specific CAR-T cells. PDAC has a unique microenvironment that consists of abundant cancer-associated fibroblasts (CAFs), which could secrete stromal cell-derived factor 1α (SDF-1α), the ligand of CXCR4. Then, we constructed and explored CLDN18.2-targeted CAR-T cells with CXCR4 co-expression in treating immunocompetent mouse models of PDAC. The results indicated that CXCR4 could promote the infiltration of CAR-T cells and enhance their efficacy in vivo. Mechanistically, the activation of signal transducer and activator of transcription 3 (STAT3) signaling was impaired in CXCR4 CAR-T cells, which reduced the release of inflammatory factors, such as tumor necrosis factor-α, IL-6, and IL-17A. Then, the lower release of inflammatory factors suppressed SDF-1α secretion in CAFs via the nuclear factor κB (NF-κB) pathway. Therefore, the decreased secretion of SDF-1α in feedback decreased the migration of myeloid-derived suppressor cells (MDSCs) in tumor sites. Overall, our study demonstrated that CXCR4 CAR-T cells could traffic more into tumor sites and also suppress MDSC migration via the STAT3/NF-κB/SDF-1α axis to obtain better efficacy in treating CLDN18.2-positive pancreatic cancer. Our findings provide a theoretical rationale for CXCR4 CAR-T cell therapy in PDAC.


Assuntos
Células Supressoras Mieloides , Neoplasias Pancreáticas , Receptores de Antígenos Quiméricos , Camundongos , Animais , NF-kappa B/metabolismo , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Células Supressoras Mieloides/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Movimento Celular/fisiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Linfócitos T/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Microambiente Tumoral
20.
Artigo em Inglês | MEDLINE | ID: mdl-38804038

RESUMO

Venous malformations are the most common congenital vascular malformations, and the incidence rate is high. Previous studies have confirmed that a variety of polymorphisms within the miRNA functional region are associated with tumor susceptibility. We examined the correlation between miR-618 rs2682818 C>A and risk of developing venous malformation in a southern Chinese population (1113 patients and 1158 controls). TaqMan genotyping of miR-618 rs2682818 C>A was conducted utilizing real-time fluorescent quantitative PCR. The miR-618 rs2682818 polymorphism was not correlated with susceptibility to venous malformation (CA/AA vs. CC: adjusted odds ratio [AOR] = 1.00, 95% confidence interval [CI] = 0.81-1.25, p = 0.994; AA vs. CC/CA: AOR = 1.10, 95% CI = 0.73-1.65, p = 0.646). Stratified analysis of different subtypes of venous malformation revealed that there was no significant difference in the rs2682818 C>A polymorphism genotypes across these subtypes. Our results indicate that miR-618 rs2682818 C>A polymorphism is not correlated with the susceptibility to venous malformation.

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