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1.
Lupus Sci Med ; 11(1)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724181

RESUMEN

OBJECTIVE: To identify new genetic variants associated with SLE in Taiwan and establish polygenic risk score (PRS) models to improve the early diagnostic accuracy of SLE. METHODS: The study enrolled 2429 patients with SLE and 48 580 controls from China Medical University Hospital in Taiwan. A genome-wide association study (GWAS) and PRS analyses of SLE and other three SLE markers, namely ANA, anti-double-stranded DNA antibody (dsDNA) and anti-Smith antibody (Sm), were conducted. RESULTS: Genetic variants associated with SLE were identified through GWAS. Some novel genes, which have been previously reported, such as RCC1L and EGLN3, were revealed to be associated with SLE in Taiwan. Multiple PRS models were established, and optimal cut-off points for each PRS were determined using the Youden Index. Combining the PRSs for SLE, ANA, dsDNA and Sm yielded an area under the curve of 0.64 for the optimal cut-off points. An analysis of human leucocyte antigen (HLA) haplotypes in SLE indicated that individuals with HLA-DQA1*01:01 and HLA-DQB1*05:01 were at a higher risk of being classified into the SLE group. CONCLUSIONS: The use of PRSs to predict SLE enables the identification of high-risk patients before abnormal laboratory data were obtained or symptoms were manifested. Our findings underscore the potential of using PRSs and GWAS in identifying SLE markers, offering promise for early diagnosis and prediction of SLE.


Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Lupus Eritematoso Sistémico , Herencia Multifactorial , Humanos , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/epidemiología , Taiwán/epidemiología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Cadenas alfa de HLA-DQ/genética , Estudios de Casos y Controles , Anticuerpos Antinucleares/sangre , Cadenas beta de HLA-DQ/genética , Factores de Riesgo , Haplotipos , Polimorfismo de Nucleótido Simple , Puntuación de Riesgo Genético
2.
Cell Death Dis ; 15(5): 310, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38697967

RESUMEN

Breast cancer (BC) is the most common cancer and the leading cause of cancer-related deaths in women worldwide. The 5-year survival rate is over 90% in BC patients, but once BC cells metastasis into distal organs, it is dramatically decreasing to less than 30%. Especially, triple-negative breast cancer (TNBC) patients usually lead to poor prognosis and survival because of metastasis. Understanding the underline mechanisms of TNBC metastasis is a critical issue. Non-coding RNAs, including of lncRNAs and microRNAs, are non-protein-coding transcripts and have been reported as important regulators in TNBC metastasis. However, the underline mechanisms for non-coding RNAs regulating TNBC metastasis remain largely unclear. Here, we found that lncRNA MIR4500HG003 was highly expressed in highly metastatic MDA-MB-231 TNBC cells and overexpression of MIR4500HG003 enhanced metastasis ability in vitro and in vivo and promoted MMP9 expression. Furthermore, we found MIR4500HG003 physically interacted with miR-483-3p and reporter assay showed miR-483-3p attenuated MMP9 expression. Importantly, endogenous high expressions of MIR4500HG003 were correlated with tumor recurrence in TNBC patients with tumor metastasis. Taken together, our findings suggested that MIR4500HG003 promotes metastasis of TNBC through miR-483-3p-MMP9 signaling axis and may be used as potential prognostic marker for TNBC patients.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Metaloproteinasa 9 de la Matriz , MicroARNs , Metástasis de la Neoplasia , ARN Largo no Codificante , Neoplasias de la Mama Triple Negativas , Humanos , MicroARNs/metabolismo , MicroARNs/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Femenino , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/genética , Línea Celular Tumoral , Animales , Ratones , Ratones Desnudos , Movimiento Celular/genética , Ratones Endogámicos BALB C
3.
Biomed J ; : 100725, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38608873

RESUMEN

BACKGROUND: Tourette syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics. Several susceptibility loci associated with TS have been identified previously in populations of European descent using genome-wide association studies (GWAS). However, the exact pathogenic mechanism underlying TS is unknown; additionally, the results of previous GWAS for TS were based on Western populations, which may not translate to other populations. Therefore, we conducted a GWAS in Taiwanese patients with TS and chronic tic disorders (CTDs), with an aim to elucidate the genetic basis and potential risk factors for TS in this population. METHODS: GWAS was performed on a Taiwanese TS/CTDs cohort with a sample size of 1,007 patients with TS and 25,522 ancestry-matched controls. Additionally, polygenic risk score was calculated and assessed. RESULTS: Genome-wide significant locus, rs12313062 (p=1.43 × 10-8) and other 9 single nucleotide polymorphisms, were identified in chromosomes 12q23.2, associated with DRAM1 and was a novel susceptibility locus identified in TS/CTDs group. DRAM1, a lysosomal transmembrane protein regulated by p53, modulates autophagy and apoptosis, with potential implications for neuropsychiatric conditions associated with autophagy disruption. CONCLUSIONS: This study conducted the first GWAS for TS in a Taiwanese population, identifying a significant locus on chromosome 12q23.2 associated with DRAM1. These findings provide novel insights into the neurobiology of TS and potential directions for future research in this area.

4.
J Cell Mol Med ; 28(7): e18243, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38509740

RESUMEN

Humans lacking heme oxygenase 1 (HMOX1) display growth retardation, haemolytic anaemia, and vulnerability to stress; however, cardiac function remains unclear. We aimed to explore the cardiac function of zebrafish lacking hmox1a at baseline and in response to stress. We generated zebrafish hmox1a mutants using CRISPR/Cas9 genome editing technology. Deletion of hmox1a increases cardiac output and further induces hypertrophy in adults. Adults lacking hmox1a develop myocardial interstitial fibrosis, restrain cardiomyocyte proliferation and downregulate renal haemoglobin and cardiac antioxidative genes. Larvae lacking hmox1a fail to respond to hypoxia, whereas adults are insensitive to isoproterenol stimulation in the heart, suggesting that hmox1a is necessary for cardiac response to stress. Haplodeficiency of hmox1a stimulates non-mitochondrial respiration and cardiac cell proliferation, increases cardiac output in larvae in response to hypoxia, and deteriorates cardiac function and structure in adults upon isoproterenol treatment. Intriguingly, haplodeficiency of hmox1a upregulates cardiac hmox1a and hmox1b in response to isoproterenol. Collectively, deletion of hmox1a results in cardiac remodelling and abrogates cardiac response to hypoxia and isoproterenol. Haplodeficiency of hmox1a aggravates cardiac response to the stress, which could be associated with the upregulation of hmox1a and hmox1b. Our data suggests that HMOX1 homeostasis is essential for maintaining cardiac function and promoting cardioprotective effects.


Asunto(s)
Cardiomiopatías , Hemo Oxigenasa (Desciclizante) , Animales , Humanos , Pez Cebra/genética , Isoproterenol/farmacología , Hemo-Oxigenasa 1/genética , Miocardio , Hipoxia , Miocitos Cardíacos
5.
Int J Mol Sci ; 25(6)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38542204

RESUMEN

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. The prevalence and phenotypes of AMD differ among populations, including between people in Taiwan and other regions. We performed a genome-wide association study to identify genetic variants and to develop genetic models to predict the risk of AMD development and progression in the Taiwanese population. In total, 4039 patients with AMD and 16,488 non-AMD controls (aged ≥ 65 years) were included. We identified 31 AMD-associated variants (p < 5 × 10-8) on chromosome 10q26, surrounding PLEKHA1-ARMS2-HTRA1. Two genetic models were constructed using the clump and threshold method. Model 1 included the single nucleotide polymorphism rs11200630 and showed a 1.31-fold increase in the risk of AMD per risk allele (95% confidence interval (CI) = 1.20-1.43, p < 0.001). In model 2, 1412 single-nucleotide polymorphisms were selected to construct a polygenic risk score (PRS). Individuals with the top 5% PRS had a 1.40-fold higher AMD risk compared with that of individuals with a PRS in the bottom quartile (95% CI = 1.04-1.89, p = 0.025). Moreover, the PRS in the upper quartile was related to a decreased age at AMD diagnosis by 0.62 years (95% CI = -1.15, -0.09, p = 0.023). Both genetic models provide useful predictive power for populations at high risk of AMD, affording a basis for identifying patients requiring close follow-up and early intervention.


Asunto(s)
Degeneración Macular , Proteínas , Anciano , Humanos , Proteínas/genética , Estudio de Asociación del Genoma Completo , Degeneración Macular/diagnóstico , Degeneración Macular/epidemiología , Degeneración Macular/genética , Serina Peptidasa A1 que Requiere Temperaturas Altas/genética , Polimorfismo de Nucleótido Simple , Diagnóstico Precoz , Predisposición Genética a la Enfermedad , Factores de Riesgo , Genotipo
6.
Artículo en Inglés | MEDLINE | ID: mdl-38347317

RESUMEN

Parentage testing is crucial for forensic DNA analysis, using short tandem repeats (STRs). Single nucleotide polymorphisms (SNPs) with high minor allele frequency (MAF) are promising for human identification. This study aimed to develop SNP markers for parentage testing in the Taiwanese population and compare their accuracy with STRs. The TPMv1 SNP microarray (714,457 SNPs) was used to screen 180,000 Taiwanese individuals and analyze the SNP data using PLINK. After quality control, allelic distribution, and MAF considerations, a set of SNPs with significant inheritance information was selected. Parentage testing was conducted on 355 single parent-child pairs using both STRs and SNPs, employing three kinship algorithms: identity by descent, kinship-based inference for genome-wide association studies, and the combined paternity index/probability of paternity (CPI/PP). An Affymetrix signature probe for kinship testing (ASP) was also used. Based on the quality control and selection criteria, 176 SNPs with MAF > 0.4995 were selected from the Taiwanese population. The CPI/PP results calculated using SNPs were consistent with the STR results. The accuracy of the SNPs used in the single-parent-child parentage testing was > 99.99%. The set of 176 SNPs had a higher identification rate in the single parent-child parentage test than in the ASP. The CPI/PP value calculated using 176 SNPs was also more accurate than that calculated using ASP. Our findings suggest that these 176 SNPs could be used for single-parent-child parentage identification in the Taiwanese population.

7.
Mol Pharmacol ; 105(2): 84-96, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-37977823

RESUMEN

The zebrafish (Danio rerio) histamine H1 receptor gene (zfH1R) was cloned in 2007 and reported to be involved in fish locomotion. Yet, no detailed characterization of its pharmacology and signaling properties have so far been reported. In this study, we pharmacologically characterized the zfH1R expressed in HEK-293T cells by means of [3H]-mepyramine binding and G protein-signaling assays. The zfH1R [dissociation constant (KD), 0.7 nM] displayed similar affinity for the antagonist [3H]-mepyramine as the human histamine H1 receptor (hH1R) (KD, 1.5 nM), whereas the affinity for histamine is 100-fold higher than for the human H1R. The zfH1R couples to Gαq/11 proteins and activates several reporter genes, i.e., NFAT, NFÏ°B, CRE, VEGF, COX-2, SRE, and AP-1, and zfH1R-mediated signaling is prevented by the Gαq/11 inhibitor YM-254890 and the antagonist mepyramine. Molecular modeling of the zfH1R and human H1R shows that the binding pockets are identical, implying that variations along the ligand binding pathway could underly the differences in histamine affinity instead. Targeting differentially charged residues in extracellular loop 2 (ECL2) using site-directed mutagenesis revealed that Arg21045x55 is most likely involved in the binding process of histamine in zfH1R. This study aids the understanding of the pharmacological differences between H1R orthologs and the role of ECL2 in histamine binding and provides fundamental information for the understanding of the histaminergic system in the zebrafish. SIGNIFICANCE STATEMENT: The use of the zebrafish as in vivo models in neuroscience is growing exponentially, which asks for detailed characterization of the aminergic neurotransmitter systems in this model. This study is the first to pharmacologically characterize the zebrafish histamine H1 receptor after expression in HEK-293T cells. The results show a high pharmacological and functional resemblance with the human ortholog but also reveal interesting structural differences and unveils an important role of the second extracellular loop in histamine binding.


Asunto(s)
Histamina , Receptores Histamínicos H1 , Animales , Humanos , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Pirilamina/farmacología , Pirilamina/metabolismo , Pez Cebra , Transducción de Señal
8.
Proc Natl Acad Sci U S A ; 121(1): e2310727120, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38150499

RESUMEN

Intrinsically disordered regions (IDR) and short linear motifs (SLiMs) play pivotal roles in the intricate signaling networks governed by phosphatases and kinases. B56δ (encoded by PPP2R5D) is a regulatory subunit of protein phosphatase 2A (PP2A) with long IDRs that harbor a substrate-mimicking SLiM and multiple phosphorylation sites. De novo missense mutations in PPP2R5D cause intellectual disabilities (ID), macrocephaly, Parkinsonism, and a broad range of neurological symptoms. Our single-particle cryo-EM structures of the PP2A-B56δ holoenzyme reveal that the long, disordered arms at the B56δ termini fold against each other and the holoenzyme core. This architecture suppresses both the phosphatase active site and the substrate-binding protein groove, thereby stabilizing the enzyme in a closed latent form with dual autoinhibition. The resulting interface spans over 190 Šand harbors unfavorable contacts, activation phosphorylation sites, and nearly all residues with ID-associated mutations. Our studies suggest that this dynamic interface is coupled to an allosteric network responsive to phosphorylation and altered globally by mutations. Furthermore, we found that ID mutations increase the holoenzyme activity and perturb the phosphorylation rates, and the severe variants significantly increase the mitotic duration and error rates compared to the normal variant.


Asunto(s)
Proteína Fosfatasa 2 , Proteína Fosfatasa 2/metabolismo , Jordania , Fosforilación , Mutación , Holoenzimas/genética , Holoenzimas/metabolismo
10.
11.
Int J Mol Sci ; 24(22)2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38003606

RESUMEN

Liver cancer is caused by complex interactions among genetic factors, viral infection, alcohol abuse, and metabolic diseases. We conducted a genome-wide association study and polygenic risk score (PRS) model in Taiwan, employing a nonspecific etiology approach, to identify genetic risk factors for hepatocellular carcinoma (HCC). Our analysis of 2836 HCC cases and 134,549 controls revealed 13 novel associated loci such as the FAM66C gene, noncoding genes, liver-fibrosis-related genes, metabolism-related genes, and HCC-related pathway genes. We incorporated the results from the UK Biobank and Japanese database into our study for meta-analysis to validate our findings. We also identified specific subtypes of the major histocompatibility complex that influence both viral infection and HCC progression. Using this data, we developed a PRS to predict HCC risk in the general population, patients with HCC, and HCC-affected families. The PRS demonstrated higher risk scores in families with multiple HCCs and other cancer cases. This study presents a novel approach to HCC risk analysis, identifies seven new genes associated with HCC development, and introduces a reproducible PRS model for risk assessment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Virosis , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/etiología , Estudio de Asociación del Genoma Completo , Factores de Riesgo , Virosis/complicaciones , Predisposición Genética a la Enfermedad
12.
Clin Cosmet Investig Dermatol ; 16: 2597-2612, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37752970

RESUMEN

Purpose: Alopecia areata (AA) is one of the most prevalent autoimmune diseases affecting humans. Given that hair follicles are immune-privileged, autoimmunity can result in disfiguring hair loss. However, the genetic basis for AA in the Taiwanese population remains unknown. Materials and Methods: A genome-wide association study was conducted using a cohort of 408 AA cases and 8167 controls. To link variants to gene relationships, we used 882 SNPs (P<1E-05) within 74 genes that were associated with AA group to build the biological networks by IPA software. HLA diplotypes and haplotypes were analyzed using Attribute Bagging (HIBAG)-R package and chi-square analysis. Results: Seven single nucleotide polymorphisms (SNPs) including LINC02006 (rs531166736, rs187306735), APC (rs112800832_C_CAT), SRP19 (rs139948960, rs144784670), EGFLAM (rs16903975) and LDLRAD3 (rs79874564) were closely associated with the AA phenotype (P<5E-08). Examination of biological networks revealed that these genomic areas are associated with antigen presentation signaling, B cell and T cell development, Th1 and Th2 activation pathways, Notch signaling, crosstalk signaling between dendritic cells and natural killer cells, and phagosome maturation. Based on human leukocyte antigen (HLA) genotype analysis, four HLA genotypes (HLA-B*15:01-*40:01, HLA-DQA1*01:02-*03:03, HLA-DQA1*01:02, and HLA-DQB1*02:01) were found to be associated with AA (adjusted p-value<0.05). HLA-DQA1*01:02 is the most significantly related gene in the Taiwanese population (adjusted p-value = 2.09E-05). Conclusion: This study successfully identified susceptibility loci associated with AA in the Taiwanese population. These findings not only shed light on the origins of AA within the Taiwanese context but also contribute to a comprehensive understanding of the genetic factors influencing AA susceptibility.

13.
Oncogene ; 42(39): 2919-2931, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37620448

RESUMEN

Leptomeningeal metastasis (LM) occurs when tumor cells spread to the leptomeningeal space surrounding the brain and the spinal cord, thereby causing poor clinical outcomes. The triple-negative breast cancer (TNBC) has been associated with symptoms of LM and mechanism remained unclear. Through proteomic analysis, we identified high expression of ICAM2 in leptomeningeal metastatic TNBC cells, which promoted the colonization of the spinal cord and resulted in poor survival in vivo. Two-way demonstration indicated that high levels of ICAM2 promoted blood-cerebrospinal fluid barrier (BCB) adhesion, trans-BCB migration, and stemness abilities and determined the specificity of LM in vivo. Furthermore, pull-down and antibody neutralizing assay revealed that ICAM2 determined the specificity of LM through interactions with ICAM1 in the choroid plexus epithelial cells. Therefore, neutralizing ICAM2 can attenuate the progression of LM and prolong survival in vivo. The results suggested that targeting ICAM2 is a potential therapeutic strategy for LM in TNBC.


Asunto(s)
Neoplasias Meníngeas , Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias de la Mama Triple Negativas/patología , Proteómica , Moléculas de Adhesión Celular , Células Epiteliales/metabolismo , Antígenos CD
14.
Int J Mol Sci ; 24(15)2023 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-37569411

RESUMEN

Rheumatoid arthritis (RA) is a systemic disease characterized by non-infectious inflammation of the joints and surrounding tissues, which can cause severe health problems, affect the patient's daily life, and even cause death. RA can be clinically diagnosed by the occurrence of blood serological markers, rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (anti-CCP). However, about 20% of RA patients exhibit negative results for both markers, which makes RA diagnosis difficult and, therefore, may delay the effective treatment. Previous studies found some evidence that human leukocyte antigen (HLA)-related genes might be the susceptibility genes for RA and their polymorphisms might contribute to varieties of susceptibility and disease severity. This study aimed for the genetic polymorphisms of the RA patient genome and their effects on the RA patient's serological makers, RF and anti-CCP. A total of 4580 patients' electronic medical records from 1992 to 2020 were retrieved from the China Medical University Hospital database. The most representative single-nucleotide polymorphisms (SNPs) were identified through a genome-wide association study (GWAS) followed by enzyme-linked immunosorbent assay (ELISA) validation using the blood from 30 additional RA patients. The results showed significant changes at the position of chromosome 6 with rs9270481 being the most significant locus, which indicated the location of the HLA-DRB1 gene. Further, patients with the CC genotype at this locus were more likely to exhibit negative results for RF and anti-CCP than those with the TT genotype. The C allele was also more likely to be associated with negative results for RF and anti-CCP. The results demonstrated that a genetic polymorphism at rs9270481 affected the expression of RF and anti-CCP in RA patients, which might indicate the necessity to develop a personalized treatment plan for each individual patient based on the genetic profile.

15.
Mol Neurobiol ; 60(11): 6660-6675, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37474883

RESUMEN

Histamine receptors mediate important physiological processes and take part in the pathophysiology of different brain disorders. Histamine receptor 1 (HRH1) is involved in the development of neurotransmitter systems, and its role in neurogenesis has been proposed. Altered HRH1 binding and expression have been detected in the brains of patients with schizophrenia, depression, and autism. Our goal was to assess the role of hrh1 in zebrafish development and neurotransmitter system regulation through the characterization of hrh1-/- fish generated by the CRISPR/Cas9 system. Quantitative PCR, in situ hybridization, and immunocytochemistry were used to study neurotransmitter systems and genes essential for brain development. Additionally, we wanted to reveal the role of this histamine receptor in larval and adult fish behavior using several quantitative behavioral methods including locomotion, thigmotaxis, dark flash and startle response, novel tank diving, and shoaling behavior. Hrh1-/- larvae displayed normal behavior in comparison with hrh1+/+ siblings. Interestingly, a transient abnormal expression of important neurodevelopmental markers was evident in these larvae, as well as a reduction in the number of tyrosine hydroxylase 1 (Th1)-positive cells, th1 mRNA, and hypocretin (hcrt)-positive cells. These abnormalities were not detected in adulthood. In summary, we verified that zebrafish lacking hrh1 present deficits in the dopaminergic and hypocretin systems during early development, but those are compensated by the time fish reach adulthood. However, impaired sociability and anxious-like behavior, along with downregulation of choline O-acetyltransferase a and LIM homeodomain transcription factor Islet1, were displayed by adult fish.


Asunto(s)
Neurogénesis , Receptores Histamínicos H1 , Pez Cebra , Animales , Humanos , Histamina/metabolismo , Neurotransmisores/metabolismo , Orexinas/metabolismo , Receptores Histamínicos H1/genética , Receptores Histamínicos H1/metabolismo , Pez Cebra/crecimiento & desarrollo
16.
bioRxiv ; 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37066309

RESUMEN

An increasing number of mutations associated with devastating human diseases are diagnosed by whole-genome/exon sequencing. Recurrent de novo missense mutations have been discovered in B56δ (encoded by PPP2R5D), a regulatory subunit of protein phosphatase 2A (PP2A), that cause intellectual disabilities (ID), macrocephaly, Parkinsonism, and a broad range of neurological symptoms. Single-particle cryo-EM structures show that the PP2A-B56δ holoenzyme possesses closed latent and open active forms. In the closed form, the long, disordered arms of B56δ termini fold against each other and the holoenzyme core, establishing dual autoinhibition of the phosphatase active site and the substrate-binding protein groove. The resulting interface spans over 190 Šand harbors unfavorable contacts, activation phosphorylation sites, and nearly all residues with ID-associated mutations. Our studies suggest that this dynamic interface is close to an allosteric network responsive to activation phosphorylation and altered globally by mutations. Furthermore, we found that ID mutations perturb the activation phosphorylation rates, and the severe variants significantly increase the mitotic duration and error rates compared to the wild variant.

17.
Small ; 19(30): e2300824, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37060220

RESUMEN

Complex oxide films stabilized by epitaxial growth can exhibit large populations of point defects which have important effects on their properties. The site occupancy of pulsed laser-deposited epitaxial terbium iron garnet (TbIG) films with excess terbium (Tb) is analyzed, in which the terbium:iron (Tb:Fe)ratio is 0.86 compared to the stoichiometric value of 0.6. The magnetic properties of the TbIG are sensitive to site occupancy, exhibiting a higher compensation temperature (by 90 K) and a lower Curie temperature (by 40 K) than the bulk Tb3 Fe5 O12 garnet. Data derived from X-ray core-level spectroscopy, magnetometry, and molecular field coefficient modeling are consistent with occupancy of the dodecahedral sites by Tb3+ , the octahedral sites by Fe3+ , Tb3+ and vacancies, and the tetrahedral sites by Fe3+ and vacancies. Energy dispersive X-ray spectroscopy in a scanning transmission electron microscope provides direct evidence of TbFe antisites. A small fraction of Fe2+ is present, and oxygen vacancies are inferred to be present to maintain charge neutrality. Variation of the site occupancies provides a path to considerable manipulation of the magnetic properties of epitaxial iron garnet films and other complex oxides, which readily accommodate stoichiometries not found in their bulk counterparts.

18.
Immunology ; 169(3): 344-357, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36762485

RESUMEN

B lymphocytes can engage in either a rapid T cell-independent pathway (TI) or a delayed long-lasting T cell-independent (TD) response through highly ordered transcriptional programs, yet the detailed underlying mechanisms are unclear. Since DNA methylation plays a key role in controlling gene expression and lineage specification, we explored the dynamics of whole-genome cytosine modifications during the ex vivo response of human B cells isolated from normal individuals by negative selection. We found that B cell differentiation following TI and TD signalling is accompanied by extensive remodelling of the epigenome, including global gain and loss of DNA methylation. The epigenetic changes map to different regions of the B cell genome, including non- C-phosphate-G CpG islands, indicating that modifications of distal regulatory elements likely regulate specific gene transcription in B cells. Non-CpG methylation also occurs in differentiating human B cells, suggesting that this DNA modification is involved in transcriptional regulation of B cell genes with promoters exhibiting a low-density methylation, possibly by changing the chromatin shape that could have an impact on gene expression. Most strikingly, compared to TD activation, stimulation of B cells through an innate pathway induced higher levels of DNA methylation modifications at CpG, CHG and CGG contexts, supporting the view that DNA methylation modifications are used in distinct trajectories to specify the TI and TD B lymphocyte responses.


Asunto(s)
Linfocitos B , Metilación de ADN , Humanos , Epigénesis Genética , Regulación de la Expresión Génica , Islas de CpG/genética , Inmunidad
19.
Life Sci Alliance ; 6(3)2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36625202

RESUMEN

Multiple myeloma (MM), the second most common hematological malignancy, is generally considered incurable because of the development of drug resistance. We previously reported that hyaluronan and proteoglycan link protein 1 (HAPLN1) produced by stromal cells induces activation of NF-κB, a tumor-supportive transcription factor, and promotes drug resistance in MM cells. However, the identity of the cell surface receptor that detects HAPLN1 and thereby engenders pro-tumorigenic signaling in MM cells remains unknown. Here, we performed an unbiased cell surface biotinylation assay and identified chaperonin 60 (CH60) as the direct binding partner of HAPLN1 on MM cells. Cell surface CH60 specifically interacted with TLR4 to evoke HAPLN1-induced NF-κB signaling, transcription of anti-apoptotic genes, and drug resistance in MM cells. Collectively, our findings identify a cell surface CH60-TLR4 complex as a HAPLN1 receptor and a potential molecular target to overcome drug resistance in MM cells.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , FN-kappa B/metabolismo , Chaperonina 60 , Supervivencia Celular , Receptor Toll-Like 4
20.
Cancer Gene Ther ; 30(3): 404-413, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36400965

RESUMEN

Currently, the survival rate for breast cancer is more than 90%, but once the cancer cells metastasize to distal organs, the survival rate is dramatically reduced, to less than 30%. Triple-negative breast cancer accounts for 15-20% of all breast cancers. Triple-negative breast cancer (TNBC) is associated with poor prognostic and diagnostic outcomes due to the limiting therapeutic strategies, relative to non-TNBC breast cancers. Therefore, the development of targeted therapy for TNBC metastasis remains an urgent issue. In this study, high Carboxyl-terminal modulator protein (CTMP) is significantly associated with recurrence and disease-free survival rate in TNBC patients. Overexpression of CTMP promotes migration and invasion abilities in BT549 cells. Down-regulating of CTMP expression inhibits migration and invasion abilities in MDA-MB-231 cells. In vivo inoculation of high-CTMP cells enhances distant metastasis in mice. The metastasis incidence rate is decreased in mice injected with CTMP-downregulating MDA-MB-231 cells. Gene expression microarray analysis indicates the Akt-dependent pathway is significantly enhanced in CTMP overexpressing cells compared to the parental cells. Blocking Akt activation via Akt inhibitor treatment or co-expression of the dominant-negative form of Akt proteins successfully abolishes the CTMP mediating invasion in TNBC cells. Our findings suggest that CTMP is a potential diagnostic marker for recurrence and poor disease-free survival in TNBC patients. CTMP promotes TNBC metastasis via the Akt-activation-dependent pathway.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Animales , Humanos , Ratones , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Palmitoil-CoA Hidrolasa/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/metabolismo , Femenino
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