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1.
J Invasive Cardiol ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662951

RESUMEN

A 33-year-old female presented to our out-patient department with worsening shortness of breath over the past 2 years.

3.
Pharmacogenomics ; 25(3): 147-160, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38426301

RESUMEN

Aim: The CYP2D6 gene is highly polymorphic, causing large interindividual variability in the metabolism of several clinically important drugs. Materials & methods: The authors investigated the diversity and distribution of CYP2D6 alleles in Indians using whole genome sequences (N = 1518). Functional consequences were assessed using pathogenicity scores and molecular dynamics simulations. Results: The analysis revealed population-specific CYP2D6 alleles (*86, *7, *111, *112, *113, *99) and remarkable differences in variant and phenotype frequencies with global populations. The authors observed that one in three Indians could benefit from a dose alteration for psychiatric drugs with accurate CYP2D6 phenotyping. Molecular dynamics simulations revealed large conformational fluctuations, confirming the predicted reduced function of *86 and *113 alleles. Conclusion: The findings emphasize the utility of comprehensive CYP2D6 profiling for aiding precision public health.


Asunto(s)
Citocromo P-450 CYP2D6 , Genómica , Humanos , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Alelos , Fenotipo , Genotipo
4.
BMJ Open Diabetes Res Care ; 12(2)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38471670

RESUMEN

INTRODUCTION: Genetic variants contribute to differential responses to non-insulin antidiabetic drugs (NIADs), and consequently to variable plasma glucose control. Optimal control of plasma glucose is paramount to minimizing type 2 diabetes-related long-term complications. India's distinct genetic architecture and its exploding burden of type 2 diabetes warrants a population-specific survey of NIAD-associated pharmacogenetic (PGx) variants. The recent availability of large-scale whole genomes from the Indian population provides a unique opportunity to generate a population-specific map of NIAD-associated PGx variants. RESEARCH DESIGN AND METHODS: We mined 1029 Indian whole genomes for PGx variants, drug-drug interaction (DDI) and drug-drug-gene interactions (DDGI) associated with 44 NIADs. Population-wise allele frequencies were estimated and compared using Fisher's exact test. RESULTS: Overall, we found 76 known and 52 predicted deleterious common PGx variants associated with response to type 2 diabetes therapy among Indians. We report remarkable interethnic differences in the relative cumulative counts of decreased and increased response-associated alleles across NIAD classes. Indians and South Asians showed a significant excess of decreased metformin response-associated alleles compared with other global populations. Network analysis of shared PGx genes predicts high DDI risk during coadministration of NIADs with other metabolic disease drugs. We also predict an increased CYP2C19-mediated DDGI risk for CYP3A4/3A5-metabolized NIADs, saxagliptin, linagliptin and glyburide when coadministered with proton-pump inhibitors (PPIs). CONCLUSIONS: Indians and South Asians have a distinct PGx profile for antidiabetes drugs, marked by an excess of poor treatment response-associated alleles for various NIAD classes. This suggests the possibility of a population-specific reduced drug response in atleast some NIADs. In addition, our findings provide an actionable resource for accelerating future diabetes PGx studies in Indians and South Asians and reconsidering NIAD dosing guidelines to ensure maximum efficacy and safety in the population.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemiantes , Humanos , Hipoglucemiantes/uso terapéutico , Variantes Farmacogenómicas , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Insulina/uso terapéutico , Frecuencia de los Genes , Insulina Regular Humana
5.
JCI Insight ; 9(5)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329813

RESUMEN

The human adult immune system maintains normal T cell counts and compensates for T cell loss throughout life, mainly through peripheral homeostatic proliferation after the ability of the thymus to generate new T cells has rapidly declined at adolescence. This process is mainly driven by STAT5-activating cytokines, most importantly IL-7, and is very effective in maintaining a large naive CD4+ T cell compartment into older age. Here, we describe that naive CD4+ T cells undergo adaptations to optimize IL-7 responses by upregulating the guanine-nucleotide exchange factor PREX1 in older age. PREX1 promotes nuclear translocation of phosphorylated STAT5, thereby supporting homeostatic proliferation in response to IL-7. Through the same mechanism, increased expression of PREX1 also biases naive cells to differentiate into effector T cells. These findings are consistent with the concept that primarily beneficial adaptations during aging, i.e., improved homeostasis, account for unfavorable functions of the aged immune system, in this case biased differentiation.


Asunto(s)
Linfocitos T CD4-Positivos , Factor de Transcripción STAT5 , Adulto , Humanos , Anciano , Factor de Transcripción STAT5/metabolismo , Interleucina-7/metabolismo , Proliferación Celular , Homeostasis , Factores de Intercambio de Guanina Nucleótido/metabolismo
6.
Trials ; 25(1): 110, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38331842

RESUMEN

BACKGROUND: Preterm and term small for gestational age (SGA) babies are at high risk of experiencing malnutrition and impaired neurodevelopment. Standalone interventions have modest and sometimes inconsistent effects on growth and neurodevelopment in these babies. For greater impact, intervention may be needed in multiple domains-health, nutrition, and psychosocial care and support. Therefore, the combined effects of an integrated intervention package for preterm and term SGA on growth and neurodevelopment are worth investigating. METHODS: An individually randomized controlled trial is being conducted in urban and peri-urban low to middle-socioeconomic neighborhoods in South Delhi, India. Infants are randomized (1:1) into two strata of 1300 preterm and 1300 term SGA infants each to receive the intervention package or routine care. Infants will be followed until 12 months of age. Outcome data will be collected by an independent outcome ascertainment team at infant ages 1, 3, 6, 9, and 12 months and at 2, 6, and 12 months after delivery for mothers. DISCUSSION: The findings of this study will indicate whether providing an intervention that addresses factors known to limit growth and neurodevelopment can offer substantial benefits to preterm or term SGA infants. The results from this study will increase our understanding of growth and development and guide the design of public health programs in low- and middle-income settings for vulnerable infants. TRIAL REGISTRATION: The trial has been registered prospectively in Clinical Trial Registry - India # CTRI/2021/11/037881, Registered on 08 November 2021.


Asunto(s)
Recien Nacido Prematuro , Recién Nacido Pequeño para la Edad Gestacional , Recién Nacido , Lactante , Femenino , Niño , Humanos , Recien Nacido Prematuro/fisiología , Edad Gestacional , Estado Nutricional , Madres , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Cardiovasc Res ; 120(6): 630-643, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38230606

RESUMEN

AIMS: Human pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) provide a platform to identify and characterize factors that regulate the maturation of CMs. The transition from an immature foetal to an adult CM state entails coordinated regulation of the expression of genes involved in myofibril formation and oxidative phosphorylation (OXPHOS) among others. Lysine demethylase 5 (KDM5) specifically demethylates H3K4me1/2/3 and has emerged as potential regulators of expression of genes involved in cardiac development and mitochondrial function. The purpose of this study is to determine the role of KDM5 in iPSC-CM maturation. METHODS AND RESULTS: KDM5A, B, and C proteins were mainly expressed in the early post-natal stages, and their expressions were progressively downregulated in the post-natal CMs and were absent in adult hearts and CMs. In contrast, KDM5 proteins were persistently expressed in the iPSC-CMs up to 60 days after the induction of myogenic differentiation, consistent with the immaturity of these cells. Inhibition of KDM5 by KDM5-C70 -a pan-KDM5 inhibitor, induced differential expression of 2372 genes, including upregulation of genes involved in fatty acid oxidation (FAO), OXPHOS, and myogenesis in the iPSC-CMs. Likewise, genome-wide profiling of H3K4me3 binding sites by the cleavage under targets and release using nuclease assay showed enriched of the H3K4me3 peaks at the promoter regions of genes encoding FAO, OXPHOS, and sarcomere proteins. Consistent with the chromatin and gene expression data, KDM5 inhibition increased the expression of multiple sarcomere proteins and enhanced myofibrillar organization. Furthermore, inhibition of KDM5 increased H3K4me3 deposits at the promoter region of the ESRRA gene and increased its RNA and protein levels. Knockdown of ESRRA in KDM5-C70-treated iPSC-CM suppressed expression of a subset of the KDM5 targets. In conjunction with changes in gene expression, KDM5 inhibition increased oxygen consumption rate and contractility in iPSC-CMs. CONCLUSION: KDM5 inhibition enhances maturation of iPSC-CMs by epigenetically upregulating the expressions of OXPHOS, FAO, and sarcomere genes and enhancing myofibril organization and mitochondrial function.


Asunto(s)
Diferenciación Celular , Ácidos Grasos , Células Madre Pluripotentes Inducidas , Miocitos Cardíacos , Miofibrillas , Oxidación-Reducción , Fosforilación Oxidativa , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/metabolismo , Humanos , Ácidos Grasos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/enzimología , Miofibrillas/metabolismo , Miofibrillas/enzimología , Células Cultivadas , Histonas/metabolismo , Histonas/genética , Proteína 2 de Unión a Retinoblastoma/metabolismo , Proteína 2 de Unión a Retinoblastoma/genética , Regulación del Desarrollo de la Expresión Génica , Mitocondrias Cardíacas/enzimología , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/genética , Regiones Promotoras Genéticas
8.
Mitochondrion ; 75: 101844, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38237647

RESUMEN

Genomic investigations on an infant who presented with a putative mitochondrial disorder led to identification of compound heterozygous deletion with an overlapping region of ∼142 kb encompassing two nuclear encoded genes namely ERCC8 and NDUFAF2. Investigations on fetal-derived fibroblast culture demonstrated impaired bioenergetics and mitochondrial dysfunction, which explains the phenotype and observed infant mortality in the present study. The genetic findings from this study extended the utility of whole-genome sequencing as it led to development of a MLPA-based assay for carrier screening in the extended family and the prenatal testing aiding in the birth of two healthy children.


Asunto(s)
Mortalidad Infantil , Mitocondrias , Lactante , Niño , Embarazo , Femenino , Humanos , Mitocondrias/genética , Secuenciación Completa del Genoma , Metabolismo Energético , Genómica , Factores de Transcripción/genética , Enzimas Reparadoras del ADN/genética , Chaperonas Moleculares/genética , Proteínas Mitocondriales/genética
9.
Photochem Photobiol Sci ; 23(1): 65-78, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38006523

RESUMEN

The excited state relaxation dynamics of 2-(2'-hydroxyphenyl)benzothiazole (HBT) in the gas phase and the solvents have been explored experimentally and theoretically. However, the fundamental mechanism of its emission in aggregates is still unexplored. In this article, we have presented a detail investigation of solvent-regulated excited state (ES) reactions for HBT aggregates with the aid of several experimental and theoretical research. The careful investigation of solvatochromic and electrochemical behavior elucidates that the emission around 460 nm of HBT in DMSO and DMSO-water fraction correspond to the excited state internal charge transfer (ESICT). The quantum chemical analysis further supports this observation. The concentration-dependent 1H NMR and emission studies of HBT in DMSO revealed the formation of aggregates at higher concentrations that facilitate the charge transfer. The emission pattern of HBT in the AcN-water fraction demonstrates that the sequential internal charge transfer-proton transfer (ESICT-ESIPT) occurs in HBT aggregates. The pH studies show that HBT aggregates are potential ratiometric sensors for near-physiological pH ranges. Moreover, a ground-state zwitterionic conformation of HBT is observed in the basic medium formed by ground-state internal proton transfer (GSIPT). Overall, this study provides a better understanding of solvent-regulated ES reaction mechanism in the case of HBT aggregates and other substituted HBT compound aggregates published previously.

10.
Neurogenetics ; 25(1): 13-25, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37917284

RESUMEN

An intronic bi-allelic pentanucleotide repeat expansion mutation, (AAGGG)400-2000, at AAAAG repeat locus in RFC1 gene, is known as underlying genetic cause in cases with cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) and late-onset sporadic ataxia. Biallelic positive cases carry a common recessive risk haplotype, "AAGA," spanning RFC1 gene. In this study, our aim is to find prevalence of bi-allelic (AAGGG)exp in Indian ataxia and other neurological disorders and investigate the complexity of RFC1 repeat locus and its potential association with neurodegenerative diseases in Indian population-based cohorts. We carried out repeat number and repeat type estimation using flanking PCR and repeat primed PCR (AAAAG/AAAGG/AAGGG) in four Indian disease cohorts and healthy controls. Haplotype assessment of suspected cases was done by genotyping and confirmed by Sanger sequencing. Blood samples and consent of all the cases and detailed clinical details of positive cases were collected in collaboration with A.I.I.M.S. Furthermore, comprehension of RFC1 repeat locus and risk haplotype analysis in Indian background was performed on the NGS data of Indian healthy controls by ExpansionHunter, ExpansionHunter Denovo, and PHASE analysis, respectively. Genetic screening of RFC1-TNR locus in 1998 uncharacterized cases (SCA12: 87; uncharacterized ataxia: 1818, CMT: 93) and 564 heterogenous controls showed that the frequency of subjects with bi-allelic (AAGGG)exp are 1.15%, < 0.05%, 2.15%, and 0% respectively. Two RFC1 positive sporadic late-onset ataxia cases, one bi-allelic (AAGGG)exp and another, (AAAGG)~700/(AAGGG)exp, had recessive risk haplotype and CANVAS symptoms. Long normal alleles, 15-27, are significantly rare in ataxia cohort. In IndiGen control population (IndiGen; N = 1029), long normal repeat range, 15-27, is significantly associated with A3G3 and some rare repeat motifs, AGAGG, AACGG, AAGAG, and AAGGC. Risk-associated "AAGA" haplotype of the original pathogenic expansion of A2G3 was found associated with the A3G3 representing alleles in background population. Apart from bi-allelic (AAGGG)exp, we report cases with a new pathogenic expansion of (AAAGG)exp/(AAGGG)exp in RFC1 and recessive risk haplotype. We found different repeat motifs at RFC1 TNR locus, like AAAAG, AAAGG, AAAGGG, AAAAGG, AAGAG, AACGG, AAGGC, AGAGG, and AAGGG, in Indian background population except ACAGG and (AAAGG)n/(AAGGG)n. Our findings will help in further understanding the role of long normal repeat size and different repeat motifs, specifically AAAGG, AAAGGG, and other rare repeat motifs, at the RFC1 locus.


Asunto(s)
Ataxia Cerebelosa , Enfermedades del Sistema Nervioso Periférico , Enfermedades Vestibulares , Humanos , Ataxia Cerebelosa/genética , Ataxia Cerebelosa/diagnóstico , Ataxia
11.
PLoS One ; 18(12): e0296215, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38134191

RESUMEN

BACKGROUND: There is a paucity of studies which have examined associations between ultrasound based fetal anthropometric parameters and neurodevelopment in all infants. We examined the association between ultrasound based fetal anthropometric parameters and neurodevelopment in all infants through a secondary analysis of data collected in a large community based randomized controlled trial. METHODS: A total of 1465 mother-child dyads were included. Ultrasound based fetal anthropometric parameters which included the head circumference (HC), abdominal circumference (AC), femur length (FL), biparietal diameter (BPD) and transcerebellar diameter (TCD) were collected at 26-28 weeks of gestation and their association with neurodevelopment at 24 months of age was examined. RESULTS: Only the transcerebellar diameter z score was positively associated +0.54 units (95% CI: 0.15, 0.93) with motor composite score. When the neurodevelopment outcomes were analyzed as categorical, none of the fetal variables were associated with risk of moderate to severe neurodevelopment impairment. CONCLUSION: The findings suggest that transcerebellar diameter could be useful for early prediction of neurodevelopmental outcomes in childhood. CLINICAL TRIAL REGISTRATION: Clinical trial registration of Women and Infants Integrated Interventions for Growth Study Clinical Trial Registry-India, #CTRI/2017/06/008908; Registered on: 23/06/2017, (http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=19339&EncHid=&userName=society%20for%20applied%20studies).


Asunto(s)
Atención Prenatal , Ultrasonografía Prenatal , Embarazo , Lactante , Humanos , Femenino , Antropometría , Cefalometría , Feto/diagnóstico por imagen , Edad Gestacional , Desarrollo Fetal
12.
Front Immunol ; 14: 1250916, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37662959

RESUMEN

Immune memory is a requisite and remarkable property of the immune system and is the biological foundation of the success of vaccinations in reducing morbidity from infectious diseases. Some vaccines and infections induce long-lasting protection, but immunity to other vaccines and particularly in older adults rarely persists over long time periods. Failed induction of an immune response and accelerated waning of immune memory both contribute to the immuno-compromised state of the older population. Here we review how T cell memory is influenced by age. T cell memory is maintained by a dynamic population of T cells that are heterogeneous in their kinetic parameters under homeostatic condition and their function. Durability of T cell memory can be influenced not only by the loss of a clonal progeny, but also by broader changes in the composition of functional states and transition of T cells to a dysfunctional state. Genome-wide single cell studies on total T cells have started to provide insights on the influence of age on cell heterogeneity over time. The most striking findings were a trend to progressive effector differentiation and the activation of pro-inflammatory pathways, including the emergence of CD4+ and CD8+ cytotoxic subsets. Genome-wide data on antigen-specific memory T cells are currently limited but can be expected to provide insights on how changes in T cell subset heterogeneity and transcriptome relate to durability of immune protection.


Asunto(s)
Memoria Inmunológica , Células T de Memoria , Diferenciación Celular , Homeostasis
13.
J Clin Exp Hepatol ; 13(5): 813-819, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37693266

RESUMEN

Hepatocellular carcinoma (HCC) invades intrahepatic vessels causing tumor thrombosis. Infrequently, there is involvement of the hepatic vein (HV) and inferior vena cava (IVC). In this review, we summarize the epidemiology, classification, clinical features, and management of HCC with HV and IVC invasion. While the involvement of HV and IVC usually portends an overall poor survival, selected patients may be candidates for aggressive treatment and thus improving outcomes.

14.
Indian J Gastroenterol ; 42(5): 601-628, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37698821

RESUMEN

Proton pump inhibitors (PPIs) have been available for over three decades and are among the most commonly prescribed medications. They are effective in treating a variety of gastric acid-related disorders. They are freely available and based on current evidence, use of PPIs for inappropriate indications and duration appears to be common. Over the years, concerns have been raised on the safety of PPIs as they have been associated with several adverse effects. Hence, there is a need for PPI stewardship to promote the use of PPIs for appropriate indication and duration. With this objective, the Indian Society of Gastroenterology has formulated guidelines on the rational use of PPIs. The guidelines were developed using a modified Delphi process. This paper presents these guidelines in detail, including the statements, review of literature, level of evidence and recommendations. This would help the clinicians in optimizing the use of PPIs in their practice and promote PPI stewardship.


Asunto(s)
Revisión de la Utilización de Medicamentos , Inhibidores de la Bomba de Protones , Humanos , Pueblo Asiatico , Gastroenterología/normas , Inhibidores de la Bomba de Protones/efectos adversos , Inhibidores de la Bomba de Protones/uso terapéutico , India , Revisión de la Utilización de Medicamentos/normas
15.
J Midlife Health ; 14(1): 42-45, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680377

RESUMEN

Primary uterine diverticula are a very rare congenital anomaly of the uterus with only 21 reported cases. Even rarer is the occurrence of primary cervical diverticula with only six cases reported so far. This is a unique case of a huge abdominopelvic mass arising from cervical fibroid around an infected cervical diverticulum. A 44 year-old, P4L4 came to the OPD with a eighteen weeks size abdomino-pelvic mass. She had a failed surgery 6 months back, attempted to remove the mass. Magnetic resonance imaging revealed a cervical diverticulum which possibly had a pus collection. Relaparotomy was done. It revealed a huge cervical fibroid with dense adhesions all around the mass. A pan hysterectomy was done. In the postoperative period, she developed high-grade fever owing to the development of a pelvic collection, which had to be drained by dilating the vault sutures. Histopathology report confirmed a cervical fibroid with an infected diverticulum within. Primary uterine or cervical diverticula are a very rare anamoly which possibly arise because of a weakness in the area where the two mullerian ducts fuse. Women with this rare condition may suffer from infertility, fever and pain abdomen, acute abdomen owing to torsion or hemoperitoneum, pregnancy complications, and menorrhagia. Diverticulectomy and cervical/uterine reconstruction can be done on nulliparous women while hysterectomy can be offered to perimenopausal women. To conclude, unless known by the gynecologists, radiologists, and the pathologists, this diagnosis can be easily missed out, leading to multiple preventable complications.

16.
Sci Transl Med ; 15(712): eadh0380, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37672564

RESUMEN

Autoimmune vasculitis of the medium and large elastic arteries can cause blindness, stroke, aortic arch syndrome, and aortic aneurysm. The disease is often refractory to immunosuppressive therapy and progresses over decades as smoldering aortitis. How the granulomatous infiltrates in the vessel wall are maintained and how tissue-infiltrating T cells and macrophages are replenished are unknown. Single-cell and whole-tissue transcriptomic studies of immune cell populations in vasculitic arteries identified a CD4+ T cell population with stem cell-like features. CD4+ T cells supplying the tissue-infiltrating and tissue-damaging effector T cells survived in tertiary lymphoid structures around adventitial vasa vasora, expressed the transcription factor T cell factor 1 (TCF1), had high proliferative potential, and gave rise to two effector populations, Eomesodermin (EOMES)+ cytotoxic T cells and B cell lymphoma 6 (BCL6)+ T follicular helper-like cells. TCF1hiCD4+ T cells expressing the interleukin 7 receptor (IL-7R) sustained vasculitis in serial transplantation experiments. Thus, TCF1hiCD4+ T cells function as disease stem cells and promote chronicity and autonomy of autoimmune tissue inflammation. Remission-inducing therapies will require targeting stem-like CD4+ T cells instead of only effector T cells.


Asunto(s)
Estructuras Linfoides Terciarias , Vasculitis , Humanos , Arterias , Inflamación , Linfocitos T CD4-Positivos
17.
Nat Commun ; 14(1): 4682, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37542049

RESUMEN

The SWI/SNF ATP-dependent chromatin remodeler is a master regulator of the epigenome, controlling pluripotency and differentiation. Towards the C-terminus of the catalytic subunit of SWI/SNF is a motif called the AT-hook that is evolutionary conserved. The AT-hook is present in many chromatin modifiers and generally thought to help anchor them to DNA. We observe however that the AT-hook regulates the intrinsic DNA-stimulated ATPase activity aside from promoting SWI/SNF recruitment to DNA or nucleosomes by increasing the reaction velocity a factor of 13 with no accompanying change in substrate affinity (KM). The changes in ATP hydrolysis causes an equivalent change in nucleosome movement, confirming they are tightly coupled. The catalytic subunit's AT-hook is required in vivo for SWI/SNF remodeling activity in yeast and mouse embryonic stem cells. The AT-hook in SWI/SNF is required for transcription regulation and activation of stage-specific enhancers critical in cell lineage priming. Similarly, growth assays suggest the AT-hook is required in yeast SWI/SNF for activation of genes involved in amino acid biosynthesis and metabolizing ethanol. Our findings highlight the importance of studying SWI/SNF attenuation versus eliminating the catalytic subunit or completely shutting down its enzymatic activity.


Asunto(s)
Saccharomyces cerevisiae , Factores de Transcripción , Animales , Ratones , Factores de Transcripción/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Linaje de la Célula/genética , Cromatina , Nucleosomas/genética , ADN/metabolismo , Adenosina Trifosfato/metabolismo
19.
Dev Cell ; 58(17): 1562-1577.e8, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625403

RESUMEN

Oncogenic KRASG12D (KRAS∗) is critical for the initiation and maintenance of pancreatic ductal adenocarcinoma (PDAC) and is a known repressor of tumor immunity. Conditional elimination of KRAS∗ in genetic mouse models of PDAC leads to the reactivation of FAS, CD8+ T cell-mediated apoptosis, and complete eradication of tumors. KRAS∗ elimination recruits activated CD4+ and CD8+ T cells and promotes the activation of antigen-presenting cells. Mechanistically, KRAS∗-mediated immune evasion involves the epigenetic regulation of Fas death receptor in cancer cells, via methylation of its promoter region. Furthermore, analysis of human RNA sequencing identifies that high KRAS expression in PDAC tumors shows a lower proportion of CD8+ T cells and demonstrates shorter survival compared with tumors with low KRAS expression. This study highlights the role of CD8+ T cells in the eradication of PDAC following KRAS∗ elimination and provides a rationale for the combination of KRAS∗ targeting with immunotherapy to control PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Proteínas Proto-Oncogénicas p21(ras) , Animales , Humanos , Ratones , Apoptosis , Carcinoma Ductal Pancreático/genética , Linfocitos T CD8-positivos , Epigénesis Genética , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas p21(ras)/genética
20.
Commun Biol ; 6(1): 765, 2023 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-37479893

RESUMEN

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by high rate of therapy resistance. Since the cell of origin can impact response to therapy, it is crucial to understand the lineage composition of AML cells at time of therapy resistance. Here we leverage single-cell chromatin accessibility profiling of 22 AML bone marrow aspirates from eight patients at time of therapy resistance and following subsequent therapy to characterize their lineage landscape. Our findings reveal a complex lineage architecture of therapy-resistant AML cells that are primed for stem and progenitor lineages and spanning quiescent, activated and late stem cell/progenitor states. Remarkably, therapy-resistant AML cells are also composed of cells primed for differentiated myeloid, erythroid and even lymphoid lineages. The heterogeneous lineage composition persists following subsequent therapy, with early progenitor-driven features marking unfavorable prognosis in The Cancer Genome Atlas AML cohort. Pseudotime analysis further confirms the vast degree of heterogeneity driven by the dynamic changes in chromatin accessibility. Our findings suggest that therapy-resistant AML cells are characterized not only by stem and progenitor states, but also by a continuum of differentiated cellular lineages. The heterogeneity in lineages likely contributes to their therapy resistance by harboring different degrees of lineage-specific susceptibilities to therapy.


Asunto(s)
Cromatina , Leucemia Mieloide Aguda , Humanos , Cromatina/genética , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Diferenciación Celular , División Celular , Linaje de la Célula/genética
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