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1.
Cancers (Basel) ; 16(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39001512

RESUMO

Chronic lymphocytic leukemia (CLL) is characterized by multiple copy number alterations (CNAs) and somatic mutations that are central to disease prognosis, risk stratification, and mechanisms of therapy resistance. Fluorescence in situ hybridization (FISH) panels are widely used in clinical applications as the gold standard for screening prognostic chromosomal abnormalities in CLL. DNA sequencing is an alternative approach to identifying CNAs but is not an established method for clinical CNA screening. We sequenced DNA from 509 individuals with CLL or monoclonal B-cell lymphocytosis (MBL), the precursor to CLL, using a targeted sequencing panel of 59 recurrently mutated genes in CLL and additional amplicons across regions affected by clinically relevant CNAs [i.e., del(17p), del(11q), del(13q), and trisomy 12]. We used the PatternCNV algorithm to call CNA and compared the concordance of calling clinically relevant CNAs by targeted sequencing to that of FISH. We found a high accuracy of calling CNAs via sequencing compared to FISH. With FISH as the gold standard, the specificity of targeted sequencing was >95%, sensitivity was >86%, positive predictive value was >90%, and negative predictive value was >84% across the clinically relevant CNAs. Using targeted sequencing, we were also able to identify other common CLL-associated CNAs, including del(6q), del(14q), and gain 8q, as well as complex karyotype, defined as the presence of 3 or more chromosomal abnormalities, in 26 patients. In a single and cost-effective assay that can be performed on stored DNA samples, targeted sequencing can simultaneously detect CNAs, somatic mutations, and complex karyotypes, which are all important prognostic features in CLL.

3.
Blood Adv ; 8(9): 2118-2129, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38359367

RESUMO

ABSTRACT: High-count monoclonal B-cell lymphocytosis (HCMBL) is a precursor condition to chronic lymphocytic leukemia (CLL). We have shown that among individuals with HCMBL, the CLL-International Prognostic Index (CLL-IPI) is prognostic for time-to-first therapy (TTFT). Little is known about the prognostic impact of somatically mutated genes among individuals with HCMBL. We sequenced DNA from 371 individuals with HCMBL using a targeted sequencing panel of 59 recurrently mutated genes in CLL to identify high-impact mutations. We compared the sequencing results with that of our treatment-naïve CLL cohort (N = 855) and used Cox regression to estimate hazard ratios and 95% confidence intervals (CIs) for associations with TTFT. The frequencies of any mutated genes were lower in HCMBL (52%) than CLL (70%). At 10 years, 37% of individuals with HCMBL with any mutated gene had progressed requiring treatment compared with 10% among individuals with HCMBL with no mutations; this led to 5.4-fold shorter TTFT (95% CI, 2.6-11.0) among HCMBL with any mutated gene vs none, independent of CLL-IPI. When considering individuals with low risk of progression according to CLL-IPI, those with HCMBL with any mutations had 4.3-fold shorter TTFT (95% CI, 1.6-11.8) vs those with none. Finally, when considering both CLL-IPI and any mutated gene status, we observed individuals with HCMBL who were high risk for both prognostic factors had worse prognosis than patients with low-risk CLL (ie, 5-year progression rate of 32% vs 21%, respectively). Among HCMBL, the frequency of somatically mutated genes at diagnosis is lower than that of CLL. Accounting for both the number of mutated genes and CLL-IPI can identify individuals with HCMBL with more aggressive clinical course.


Assuntos
Linfócitos B , Progressão da Doença , Leucemia Linfocítica Crônica de Células B , Linfocitose , Mutação , Humanos , Linfocitose/genética , Linfocitose/diagnóstico , Linfocitose/terapia , Prognóstico , Masculino , Feminino , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Pessoa de Meia-Idade , Idoso , Linfócitos B/metabolismo , Linfócitos B/patologia , Adulto , Idoso de 80 Anos ou mais , Contagem de Linfócitos
4.
Blood ; 143(17): 1752-1757, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38194687

RESUMO

ABSTRACT: Monoclonal B-cell lymphocytosis (MBL) progresses to chronic lymphocytic leukemia (CLL) requiring therapy at 1% to 5% per year. Improved prediction of progression would greatly benefit individuals with MBL. Patients with CLL separate into 3 distinct epigenetic subtypes (epitypes) with high prognostic significance, and recently the intermediate epitype has been shown to be enriched for high-risk immunoglobulin lambda variable (IGLV) 3-21 rearrangements, impacting outcomes for these patients. Here, we employed this combined strategy to generate the epigenetic and light chain immunoglobulin (ELCLV3-21) signature to classify 219 individuals with MBL. The ELCLV3-21 high-risk signature distinguished MBL individuals with a high probability of progression (39.9% and 71.1% at 5 and 10 years, respectively). ELCLV3-21 improved the accuracy of predicting time to therapy for individuals with MBL compared with other established prognostic indicators, including the CLL international prognostic index (c-statistic, 0.767 vs 0.668, respectively). Comparing ELCLV3-21 risk groups in MBL vs a cohort of 226 patients with CLL revealed ELCLV3-21 high-risk individuals with MBL had significantly shorter time to therapy (P = .003) and reduced overall survival (P = .03) compared with ELCLV3-21 low-risk individuals with CLL. These results highlight the power of the ELCLV3-21 approach to identify individuals with a higher likelihood of adverse clinical outcome and may provide a more accurate approach to classify individuals with small B-cell clones.


Assuntos
Linfócitos B , Leucemia Linfocítica Crônica de Células B , Linfocitose , Humanos , Linfocitose/genética , Linfocitose/diagnóstico , Linfocitose/imunologia , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/diagnóstico , Feminino , Masculino , Linfócitos B/imunologia , Linfócitos B/patologia , Idoso , Pessoa de Meia-Idade , Prognóstico , Epigênese Genética , Idoso de 80 Anos ou mais , Adulto
5.
Bioinform Adv ; 3(1): vbad104, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600846

RESUMO

Motivation: Analyzing the overlap between two sets of genomic intervals is a frequent task in the field of bioinformatics. Typically, this is accomplished by counting the number (or proportion) of overlapped regions, which applies an arbitrary threshold to determine if two genomic intervals are overlapped. By making binary calls but disregarding the magnitude of the overlap, such an approach often leads to biased, non-reproducible, and incomparable results. Results: We developed the cobind package, which incorporates six statistical measures: the Jaccard coefficient, Sørensen-Dice coefficient, Szymkiewicz-Simpson coefficient, collocation coefficient, pointwise mutual information (PMI), and normalized PMI. These measures allow for a quantitative assessment of the collocation strength between two sets of genomic intervals. To demonstrate the effectiveness of these methods, we applied them to analyze CTCF's binding sites identified from ChIP-seq, cancer-specific open-chromatin regions (OCRs) identified from ATAC-seq of 17 cancer types, and oligodendrocytes-specific OCRs identified from scATAC-seq. Our results indicated that these new approaches effectively re-discover CTCF's cofactors, as well as cancer-specific and oligodendrocytes-specific master regulators implicated in disease and cell type development. Availability and implementation: The cobind package is implemented in Python and freely available at https://cobind.readthedocs.io/en/latest/.

6.
Gastroenterology ; 165(6): 1458-1474, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37597632

RESUMO

BACKGROUND & AIMS: Although depletion of neuronal nitric oxide synthase (NOS1)-expressing neurons contributes to gastroparesis, stimulating nitrergic signaling is not an effective therapy. We investigated whether hypoxia-inducible factor 1α (HIF1A), which is activated by high O2 consumption in central neurons, is a Nos1 transcription factor in enteric neurons and whether stabilizing HIF1A reverses gastroparesis. METHODS: Mice with streptozotocin-induced diabetes, human and mouse tissues, NOS1+ mouse neuroblastoma cells, and isolated nitrergic neurons were studied. Gastric emptying of solids and volumes were determined by breath test and single-photon emission computed tomography, respectively. Gene expression was analyzed by RNA-sequencing, microarrays, immunoblotting, and immunofluorescence. Epigenetic assays included chromatin immunoprecipitation sequencing (13 targets), chromosome conformation capture sequencing, and reporter assays. Mechanistic studies used Cre-mediated recombination, RNA interference, and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated epigenome editing. RESULTS: HIF1A signaling from physiological intracellular hypoxia was active in mouse and human NOS1+ myenteric neurons but reduced in diabetes. Deleting Hif1a in Nos1-expressing neurons reduced NOS1 protein by 50% to 92% and delayed gastric emptying of solids in female but not male mice. Stabilizing HIF1A with roxadustat (FG-4592), which is approved for human use, restored NOS1 and reversed gastroparesis in female diabetic mice. In nitrergic neurons, HIF1A up-regulated Nos1 transcription by binding and activating proximal and distal cis-regulatory elements, including newly discovered super-enhancers, facilitating RNA polymerase loading and pause-release, and by recruiting cohesin to loop anchors to alter chromosome topology. CONCLUSIONS: Pharmacologic HIF1A stabilization is a novel, translatable approach to restoring nitrergic signaling and treating diabetic gastroparesis. The newly recognized effects of HIF1A on chromosome topology may provide insights into physioxia- and ischemia-related organ function.


Assuntos
Diabetes Mellitus Experimental , Gastroparesia , Animais , Feminino , Humanos , Camundongos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Epigênese Genética , Gastroparesia/genética , Neurônios , Óxido Nítrico Sintase Tipo I
7.
Blood Adv ; 7(13): 3169-3179, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-36877634

RESUMO

TP53 aberrations, including mutations and deletion of 17p13, are important adverse prognostic markers in chronic lymphocytic leukemia (CLL) but are less studied in high count monoclonal B-cell lymphocytosis (HCMBL), an asymptomatic pre-malignant stage of CLL. Here we estimated the prevalence and impact of TP53 aberrations in 1,230 newly diagnosed treatment-naïve individuals (849 CLL, 381 HCMBL). We defined TP53 state as: wild-type (no TP53 mutations and normal 17p), single-hit (del(17p) or one TP53 mutation), or multi-hit (TP53 mutation and del(17p), TP53 mutation and loss of heterozygosity, or multiple TP53 mutations). Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for time to first treatment and overall survival by TP53 state. We found 64 (7.5%) CLL patients and 17 (4.5%) HCMBL individuals had TP53 mutations with variant allele fraction >10%. Del(17p) was present in 58 (6.8%) of CLL and 11 (2.9%) of HCMBL cases. Most individuals had wild-type (N=1,128, 91.7%) TP53 state, followed by multi-hit (N=55, 4.5%) and then single-hit (N=47, 3.8%) TP53 state. The risk of shorter time to therapy and death increased with the number of TP53 abnormalities. Compared to wild-type patients, multi-hit patients had 3-fold and single-hit patients had 1.5-fold increased risk of requiring therapy. Multi-hit patients also had 2.9-fold increased risk of death compared to wild-type. These results remained stable after accounting for other known poor prognostic factors. Both TP53 mutations and del(17p) may provide important prognostic information for HCMBL and CLL that would be missed if only one were measured.


Assuntos
Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/terapia , Proteína Supressora de Tumor p53/genética , Prognóstico , Mutação , Deleção Cromossômica
8.
Blood Cancer J ; 12(7): 99, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778390

RESUMO

Constitutively activated B cell receptor (BCR) signaling is a primary biological feature of chronic lymphocytic leukemia (CLL). The biological events controlled by BCR signaling in CLL are not fully understood and need investigation. Here, by analysis of the chromatin states and gene expression profiles of CLL B cells from patients before and after Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib treatment, we show that BTKi treatment leads to a decreased expression of APOBEC3 family genes by regulating the activity of their enhancers. BTKi treatment reduces enrichment of enhancer marks (H3K4me1 and H3K27ac) and chromatin accessibility at putative APOBEC3 enhancers. CRISPR-Cas9 directed deletion or inhibition of the putative APOBEC3 enhancers leads to reduced APOBEC3 expression. We further find that transcription factor NFATc1 couples BCR signaling with the APOBEC3 enhancer activity to control APOBEC3 expression. We also find that enhancer-regulated APOBEC3 expression contributes to replication stress in malignant B cells. In total we demonstrate a novel mechanism for BTKi suppression of APOBEC3 expression via direct enhancer regulation in an NFATc1-dependent manner, implicating BCR signaling as a potential regulator of leukemic genomic instability.


Assuntos
Desaminases APOBEC , Leucemia Linfocítica Crônica de Células B , Receptores de Antígenos de Linfócitos B , Desaminases APOBEC/biossíntese , Desaminases APOBEC/genética , Desaminases APOBEC/metabolismo , Cromatina , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo
10.
Neuro Oncol ; 24(8): 1261-1272, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231103

RESUMO

BACKGROUND: RBBP4 activates transcription by histone acetylation, but the partner histone acetyltransferases are unknown. Thus, we investigated the hypothesis that RBBP4 interacts with p300 in a complex in glioblastoma (GBM). METHODS: shRNA silencing of RBBP4 or p300 and RNAseq was used to identify genes co-regulated by RBBP4 and p300 in GBM43 patient-derived xenograft (PDX). RBBP4/p300 complex was demonstrated using proximity ligation assay (PLA) and ChIPseq delineated histone H3 acetylation and RBBP4/p300 complex binding in promoters/enhancers. Temozolomide (TMZ)-induced DNA double strand breaks (DSBs) were evaluated by γ-H2AX and proliferation by CyQuant and live cell monitoring assays. In vivo efficacy was based on survival of mice with orthotopic tumors. RESULTS: shRBBP4 and shp300 downregulated 4768 genes among which 1485 (31%) were commonly downregulated by both shRNAs, while upregulated genes were 2484, including 863 (35%) common genes. The pro-survival genes were the top-ranked among the downregulated genes, including C-MYC. RBBP4/p300 complex was demonstrated in the nucleus, and shRBBP4 or shp300 significantly sensitized GBM cells to TMZ compared to the control shNT in vitro (P < .05). Moreover, TMZ significantly prolonged the survival of mice bearing GBM22-shRBBP4 orthotopic tumors compared with control shNT tumors (median shNT survival 52 days vs. median shRBBP4 319 days; P = .001). CREB-binding protein (CBP)/p300 inhibitor CPI-1612 suppressed H3K27Ac and RBBP4/p300 complex target proteins, including C-MYC, and synergistically sensitized TMZ in vitro. Pharmacodynamic evaluation confirmed brain penetration by CPI-1612 supporting further investigation to evaluate efficacy to sensitize TMZ. CONCLUSIONS: RBBP4/p300 complex is present in GBM cells and is a potential therapeutic target.


Assuntos
Neoplasias Encefálicas , Proteína p300 Associada a E1A , Glioblastoma , Proteína 4 de Ligação ao Retinoblastoma , Acetilação , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Camundongos , Regiões Promotoras Genéticas , Proteína 4 de Ligação ao Retinoblastoma/genética , Proteína 4 de Ligação ao Retinoblastoma/metabolismo , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Nat Commun ; 12(1): 4560, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315876

RESUMO

Alcoholic hepatitis (AH) is associated with liver neutrophil infiltration through activated cytokine pathways leading to elevated chemokine expression. Super-enhancers are expansive regulatory elements driving augmented gene expression. Here, we explore the mechanistic role of super-enhancers linking cytokine TNFα with chemokine amplification in AH. RNA-seq and histone modification ChIP-seq of human liver explants show upregulation of multiple CXCL chemokines in AH. Liver sinusoidal endothelial cells (LSEC) are identified as an important source of CXCL expression in human liver, regulated by TNFα/NF-κB signaling. A super-enhancer is identified for multiple CXCL genes by multiple approaches. dCas9-KRAB-mediated epigenome editing or pharmacologic inhibition of Bromodomain and Extraterminal (BET) proteins, transcriptional regulators vital to super-enhancer function, decreases chemokine expression in vitro and decreases neutrophil infiltration in murine models of AH. Our findings highlight the role of super-enhancer in propagating inflammatory signaling by inducing chemokine expression and the therapeutic potential of BET inhibition in AH treatment.


Assuntos
Quimiocinas/biossíntese , Citocinas/farmacologia , Elementos Facilitadores Genéticos , Hepatite Alcoólica/genética , Animais , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Lipopolissacarídeos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Regiões Promotoras Genéticas/genética , RNA-Seq , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Sci Rep ; 11(1): 8318, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859327

RESUMO

T cell prolymphocytic leukemia (T-PLL) is a rare disease with aggressive clinical course. Cytogenetic analysis, whole-exome and whole-genome sequencing have identified primary structural alterations in T-PLL, including inversion, translocation and copy number variation. Recurrent somatic mutations were also identified in genes encoding chromatin regulators and those in the JAK-STAT signaling pathway. Epigenetic alterations are the hallmark of many cancers. However, genome-wide epigenomic profiles have not been reported in T-PLL, limiting the mechanistic study of its carcinogenesis. We hypothesize epigenetic mechanisms also play a key role in T-PLL pathogenesis. To systematically test this hypothesis, we generated genome-wide maps of regulatory regions using H3K4me3 and H3K27ac ChIP-seq, as well as RNA-seq data in both T-PLL patients and healthy individuals. We found that genes down-regulated in T-PLL are mainly associated with defense response, immune system or adaptive immune response, while up-regulated genes are enriched in developmental process, as well as WNT signaling pathway with crucial roles in cell fate decision. In particular, our analysis revealed a global alteration of regulatory landscape in T-PLL, with differential peaks highly enriched for binding motifs of immune related transcription factors, supporting the epigenetic regulation of oncogenes and genes involved in DNA damage response and T-cell activation. Together, our work reveals a causal role of epigenetic dysregulation in T-PLL.


Assuntos
Reprogramação Celular/genética , Epigênese Genética/genética , Epigênese Genética/fisiologia , Leucemia Prolinfocítica de Células T/genética , Leucemia Prolinfocítica de Células T/patologia , Transcrição Gênica/genética , Variações do Número de Cópias de DNA , Dano ao DNA/genética , Estudo de Associação Genômica Ampla , Humanos , Leucemia Prolinfocítica de Células T/imunologia , Ativação Linfocitária/genética , Linfócitos T/imunologia , Via de Sinalização Wnt/fisiologia
14.
J Cell Biol ; 220(5)2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33625469

RESUMO

Matrix stiffness is a central regulator of fibroblast function. However, the transcriptional mechanisms linking matrix stiffness to changes in fibroblast phenotype are incompletely understood. Here, we evaluated the effect of matrix stiffness on genome-wide chromatin accessibility in freshly isolated lung fibroblasts using ATAC-seq. We found higher matrix stiffness profoundly increased global chromatin accessibility relative to lower matrix stiffness, and these alterations were in close genomic proximity to known profibrotic gene programs. Motif analysis of these regulated genomic loci identified ZNF416 as a putative mediator of fibroblast stiffness responses. Genome occupancy analysis using ChIP-seq confirmed that ZNF416 occupies a broad range of genes implicated in fibroblast activation and tissue fibrosis, with relatively little overlap in genomic occupancy with other mechanoresponsive and profibrotic transcriptional regulators. Using loss- and gain-of-function studies, we demonstrated that ZNF416 plays a critical role in fibroblast proliferation, extracellular matrix synthesis, and contractile function. Together, these observations identify ZNF416 as novel mechano-activated transcriptional regulator of fibroblast biology.


Assuntos
Fibroblastos/fisiologia , Regulação da Expressão Gênica/genética , Transcrição Gênica/genética , Animais , Proliferação de Células/genética , Células Cultivadas , Cromatina/genética , Matriz Extracelular/genética , Fibrose/genética , Genoma/genética , Pulmão/fisiologia , Camundongos , Camundongos Transgênicos , Fenótipo
15.
Cell Mol Gastroenterol Hepatol ; 11(1): 117-145, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32771388

RESUMO

BACKGROUND & AIMS: Gastric dysfunction in the elderly may cause reduced food intake, frailty, and increased mortality. The pacemaker and neuromodulator cells interstitial cells of Cajal (ICC) decline with age in humans, and their loss contributes to gastric dysfunction in progeric klotho mice hypomorphic for the anti-aging Klotho protein. The mechanisms of ICC depletion remain unclear. Klotho attenuates Wnt (wingless-type MMTV integration site) signaling. Here, we examined whether unopposed Wnt signaling could underlie aging-associated ICC loss by up-regulating transformation related protein TRP53 in ICC stem cells (ICC-SC). METHODS: Mice aged 1-107 weeks, klotho mice, APCΔ468 mice with overactive Wnt signaling, mouse ICC-SC, and human gastric smooth muscles were studied by RNA sequencing, reverse transcription-polymerase chain reaction, immunoblots, immunofluorescence, histochemistry, flow cytometry, and methyltetrazolium, ethynyl/bromodeoxyuridine incorporation, and ex-vivo gastric compliance assays. Cells were manipulated pharmacologically and by gene overexpression and RNA interference. RESULTS: The klotho and aged mice showed similar ICC loss and impaired gastric compliance. ICC-SC decline preceded ICC depletion. Canonical Wnt signaling and TRP53 increased in gastric muscles of klotho and aged mice and middle-aged humans. Overstimulated canonical Wnt signaling increased DNA damage response and TRP53 and reduced ICC-SC self-renewal and gastric ICC. TRP53 induction persistently inhibited G1/S and G2/M cell cycle phase transitions without activating apoptosis, autophagy, cellular quiescence, or canonical markers/mediators of senescence. G1/S block reflected increased cyclin-dependent kinase inhibitor 1B and reduced cyclin D1 from reduced extracellular signal-regulated kinase activity. CONCLUSIONS: Increased Wnt signaling causes age-related ICC loss by up-regulating TRP53, which induces persistent ICC-SC cell cycle arrest without up-regulating canonical senescence markers.


Assuntos
Envelhecimento/fisiologia , Senescência Celular/fisiologia , Células Intersticiais de Cajal/fisiologia , Estômago/fisiologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Pontos de Checagem do Ciclo Celular , Feminino , Humanos , Proteínas Klotho/genética , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Modelos Animais , Estômago/citologia , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Via de Sinalização Wnt , Adulto Jovem
16.
BMC Urol ; 20(1): 173, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33121461

RESUMO

BACKGROUND: The four most commonly-mutated genes in clear cell renal cell carcinoma (ccRCC) tumors are BAP1, PBRM1, SETD2 and VHL. And, there are currently 14 known RCC germline variants that have been reproducibly shown to be associated with RCC risk. However, the association of germline genetics with tumor genetics and clinical aggressiveness are unknown. METHODS: We analyzed 420 ccRCC patients from The Cancer Genome Atlas. Molecular subtype was determined based on acquired mutations in BAP1, PBRM1, SETD2 and VHL. Aggressive subtype was defined clinically using Mayo SSIGN score and molecularly using the ccA/ccB gene expression subtype. Publically-available Hi-C data were used to link germline risk variants with candidate target genes. RESULTS: The 8q24 variant rs35252396 was significantly associated with VHL mutation status (OR = 1.6, p = 0.0037) and SSIGN score (OR = 1.9, p = 0.00094), after adjusting for multiple comparisons. We observed that, while some germline variants have interactions with nearby genes, some variants demonstrate long-range interactions with target genes. CONCLUSIONS: These data further demonstrate the link between rs35252396, HIF pathway and ccRCC clinical aggressiveness, providing a more comprehensive picture of how germline genetics and tumor genetics interact with respect to tumor development and progression.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Mutação , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/classificação , Neoplasias Renais/patologia , Masculino
17.
Cancer Res ; 80(20): 4324-4334, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32928922

RESUMO

Adenosquamous cancer of the pancreas (ASCP) is a subtype of pancreatic cancer that has a worse prognosis and greater metastatic potential than the more common pancreatic ductal adenocarcinoma (PDAC) subtype. To distinguish the genomic landscape of ASCP and identify actionable targets for this lethal cancer, we applied DNA content flow cytometry to a series of 15 tumor samples including five patient-derived xenografts (PDX). We interrogated purified sorted tumor fractions from these samples with whole-genome copy-number variant (CNV), whole-exome sequencing, and Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) analyses. These identified a variety of somatic genomic lesions targeting chromatin regulators in ASCP genomes that were superimposed on well-characterized genomic lesions including mutations in TP53 (87%) and KRAS (73%), amplification of MYC (47%), and homozygous deletion of CDKN2A (40%) that are common in PDACs. Furthermore, a comparison of ATAC-seq profiles of three ASCP and three PDAC genomes using flow-sorted PDX models identified genes with accessible chromatin unique to the ASCP genomes, including the lysine methyltransferase SMYD2 and the pancreatic cancer stem cell regulator RORC in all three ASCPs, and a FGFR1-ERLIN2 fusion associated with focal CNVs in both genes in a single ASCP. Finally, we demonstrate significant activity of a pan FGFR inhibitor against organoids derived from the FGFR1-ERLIN2 fusion-positive ASCP PDX model. Our results suggest that the genomic and epigenomic landscape of ASCP provide new strategies for targeting this aggressive subtype of pancreatic cancer. SIGNIFICANCE: These data provide a unique description of the ASCP genomic and epigenomic landscape and identify candidate therapeutic targets for this dismal cancer.


Assuntos
Carcinoma Adenoescamoso/genética , Cromatina/genética , Epigenoma , Mutação , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras) , Carcinoma Adenoescamoso/tratamento farmacológico , Carcinoma Adenoescamoso/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Cromatina/metabolismo , Humanos , Organoides , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Análise de Célula Única , Proteína Smad4/genética , Sequenciamento do Exoma
18.
Hum Mol Genet ; 29(16): 2761-2774, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32744316

RESUMO

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in Western countries. It has a strong genetic basis, showing a ~ 8-fold increased risk of CLL in first-degree relatives. Genome-wide association studies (GWAS) have identified 41 risk variants across 41 loci. However, for a majority of the loci, the functional variants and the mechanisms underlying their causal roles remain undefined. Here, we examined the genetic and epigenetic features associated with 12 index variants, along with any correlated (r2 ≥ 0.5) variants, at the CLL risk loci located outside of gene promoters. Based on publicly available ChIP-seq and chromatin accessibility data as well as our own ChIP-seq data from CLL patients, we identified six candidate functional variants at six loci and at least two candidate functional variants at each of the remaining six loci. The functional variants are predominantly located within enhancers or super-enhancers, including bi-directionally transcribed enhancers, which are often restricted to immune cell types. Furthermore, we found that, at 78% of the functional variants, the alternative alleles altered the transcription factor binding motifs or histone modifications, indicating the involvement of these variants in the change of local chromatin state. Finally, the enhancers carrying functional variants physically interacted with genes enriched in the type I interferon signaling pathway, apoptosis, or TP53 network that are known to play key roles in CLL. These results support the regulatory roles for inherited noncoding variants in the pathogenesis of CLL.


Assuntos
Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Leucemia Linfocítica Crônica de Células B/genética , Alelos , Cromatina/genética , Epigênese Genética/genética , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica , Fatores de Risco , Proteína Supressora de Tumor p53/genética
19.
Clin Transl Gastroenterol ; 11(3): e00136, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32352713

RESUMO

INTRODUCTION: Epigenetic modifications have been implicated to mediate several complications of diabetes mellitus (DM), especially nephropathy and retinopathy. Our aim was to ascertain whether epigenetic alterations in whole blood discriminate among patients with DM with normal, delayed, and rapid gastric emptying (GE). METHODS: Using the ChIP-seq (chromatin immunoprecipitation combined with next-generation sequencing) assays, we compared the genome-wide enrichment of 3 histone modifications (i.e., H3K4me3, H3K9ac, and H3K27ac) in buffy coats from 20 diabetic patients with gastrointestinal symptoms and normal (n = 6), delayed (n = 8), or rapid (n = 6) GE. RESULTS: Between patients with DM with delayed vs normal GE, there were 108 and 54 genes that were differentially bound (false discovery rate < 0.05) with H3K27ac and H3K9ac, respectively; 100 genes were differentially bound with H3K9ac in patients with rapid vs normal GE. The differentially bound genes with H3K27ac were functionally linked to the type 2 immune response, particularly Th2 cell activation and function (e.g., CCR3, CRLF2, CXCR4, IL5RA, and IL1RL1) and glucose homeostasis (FBP-1, PDE4A, and CMKLR1). For H3K9ac, the differentially occupied genes were related to T-cell development and function (e.g., ICOS and CCR3) and innate immunity (RELB, CD300LB, and CLEC2D). Compared with normal GE, rapid GE had differential H3K9ac peaks at the promoter site of diverse immunity-related genes (e.g., TNFRSF25 and CXCR4) and genes related to insulin resistance and glucose metabolism. Motif analysis disclosed enrichment of binding sites for transcription factors relevant to the pathogenesis and complications of DM. DISCUSSION: GE disturbances in DM are associated with epigenetic alterations that pertain to dysimmunity, glucose metabolism, and other complications of DM.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Epigênese Genética , Esvaziamento Gástrico/genética , Gastroenteropatias/genética , Adulto , Buffy Coat , Sequenciamento de Cromatina por Imunoprecipitação , Biologia Computacional , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Feminino , Gastroenteropatias/sangue , Gastroenteropatias/diagnóstico , Glucose/metabolismo , Código das Histonas/genética , Histonas/genética , Humanos , Resistência à Insulina/genética , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Índice de Gravidade de Doença
20.
Am J Hematol ; 95(8): 906-917, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32279347

RESUMO

Next-generation sequencing identified about 60 genes recurrently mutated in chronic lymphocytic leukemia (CLL). We examined the additive prognostic value of the total number of recurrently mutated CLL genes (i.e., tumor mutational load [TML]) or the individually mutated genes beyond the CLL international prognostic index (CLL-IPI) in newly diagnosed CLL and high-count monoclonal B-cell lymphocytosis (HC MBL). We sequenced 59 genes among 557 individuals (112 HC MBL/445 CLL) in a multi-stage design, to estimate hazard ratios (HR) and 95% confidence intervals (CI) for time-to-first treatment (TTT), adjusted for CLL-IPI and sex. TML was associated with shorter TTT in the discovery and validation cohorts, with a combined estimate of continuous HR = 1.27 (CI:1.17-1.39, P = 2.6 × 10-8 ; c-statistic = 0.76). When stratified by CLL-IPI, the association of TML with TTT was stronger and validated within low/intermediate risk (combined HR = 1.54, CI:1.37-1.72, P = 7.0 × 10-14 ). Overall, 80% of low/intermediate CLL-IPI cases with two or more mutated genes progressed to require therapy within 5 years, compared to 24% among those without mutations. TML was also associated with shorter TTT in the HC MBL cohort (HR = 1.53, CI:1.12-2.07, P = .007; c-statistic = 0.71). TML is a strong prognostic factor for TTT independent of CLL-IPI, especially among low/intermediate CLL-IPI risk, and a better predictor than any single gene. Mutational screening at early stages may improve risk stratification and better predict TTT.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leucemia Linfocítica Crônica de Células B/genética , Linfocitose/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico
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