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1.
Genome Res ; 34(2): 189-200, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38408788

RESUMO

Recent studies have revealed an unexplored population of long cell-free DNA (cfDNA) molecules in human plasma using long-read sequencing technologies. However, the biological properties of long cfDNA molecules (>500 bp) remain largely unknown. To this end, we have investigated the origins of long cfDNA molecules from different genomic elements. Analysis of plasma cfDNA using long-read sequencing reveals an uneven distribution of long molecules from across the genome. Long cfDNA molecules show overrepresentation in euchromatic regions of the genome, in sharp contrast to short DNA molecules. We observe a stronger relationship between the abundance of long molecules and mRNA gene expression levels, compared with short molecules (Pearson's r = 0.71 vs. -0.14). Moreover, long and short molecules show distinct fragmentation patterns surrounding CpG sites. Leveraging the cleavage preferences surrounding CpG sites, the combined cleavage ratios of long and short molecules can differentiate patients with hepatocellular carcinoma (HCC) from non-HCC subjects (AUC = 0.87). We also investigated knockout mice in which selected nuclease genes had been inactivated in comparison with wild-type mice. The proportion of long molecules originating from transcription start sites are lower in Dffb-deficient mice but higher in Dnase1l3-deficient mice compared with that of wild-type mice. This work thus provides new insights into the biological properties and potential clinical applications of long cfDNA molecules.


Assuntos
Carcinoma Hepatocelular , Ácidos Nucleicos Livres , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Ácidos Nucleicos Livres/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , DNA/genética , Genômica , Camundongos Knockout , Endodesoxirribonucleases/genética
2.
Proc Natl Acad Sci U S A ; 120(17): e2220982120, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37075072

RESUMO

Cell-free DNA (cfDNA) fragmentation is nonrandom, at least partially mediated by various DNA nucleases, forming characteristic cfDNA end motifs. However, there is a paucity of tools for deciphering the relative contributions of cfDNA cleavage patterns related to underlying fragmentation factors. In this study, through non-negative matrix factorization algorithm, we used 256 5' 4-mer end motifs to identify distinct types of cfDNA cleavage patterns, referred to as "founder" end-motif profiles (F-profiles). F-profiles were associated with different DNA nucleases based on whether such patterns were disrupted in nuclease-knockout mouse models. Contributions of individual F-profiles in a cfDNA sample could be determined by deconvolutional analysis. We analyzed 93 murine cfDNA samples of different nuclease-deficient mice and identified six types of F-profiles. F-profiles I, II, and III were linked to deoxyribonuclease 1 like 3 (DNASE1L3), deoxyribonuclease 1 (DNASE1), and DNA fragmentation factor subunit beta (DFFB), respectively. We revealed that 42.9% of plasma cfDNA molecules were attributed to DNASE1L3-mediated fragmentation, whereas 43.4% of urinary cfDNA molecules involved DNASE1-mediated fragmentation. We further demonstrated that the relative contributions of F-profiles were useful to inform pathological states, such as autoimmune disorders and cancer. Among the six F-profiles, the use of F-profile I could inform the human patients with systemic lupus erythematosus. F-profile VI could be used to detect individuals with hepatocellular carcinoma, with an area under the receiver operating characteristic curve of 0.97. F-profile VI was more prominent in patients with nasopharyngeal carcinoma undergoing chemoradiotherapy. We proposed that this profile might be related to oxidative stress.


Assuntos
Ácidos Nucleicos Livres , Humanos , Camundongos , Animais , Ácidos Nucleicos Livres/genética , Desoxirribonucleases/genética , Camundongos Knockout , Endonucleases/genética , Fragmentação do DNA , Endodesoxirribonucleases/genética
3.
J Hematol Oncol ; 16(1): 19, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879351

RESUMO

BACKGROUND: TP53 mutations, which are present in 5% to 10% of patients with acute myeloid leukemia (AML), are associated with treatment resistance and poor outcomes. First-line therapies for TP53-mutated (TP53m) AML consist of intensive chemotherapy (IC), hypomethylating agents (HMA), or venetoclax combined with HMA (VEN + HMA). METHODS: We conducted a systematic review and meta-analysis to describe and compare treatment outcomes in newly diagnosed treatment-naïve patients with TP53m AML. Randomized controlled trials, single-arm trials, prospective observational studies, and retrospective studies were included that reported on complete remission (CR), CR with incomplete hematologic recovery (CRi), overall survival (OS), event-free survival (EFS), duration of response (DoR), and overall response rate (ORR) among patients with TP53m AML receiving first-line treatment with IC, HMA, or VEN + HMA. RESULTS: Searches of EMBASE and MEDLINE identified 3006 abstracts, and 17 publications describing 12 studies met the inclusion criteria. Random-effects models were used to pool response rates, and time-related outcomes were analyzed with the median of medians method. IC was associated with the greatest CR rate of 43%, and CR rates were 33% for VEN + HMA and 13% for HMA. Rates of CR/CRi were comparable for IC (46%) and VEN + HMA (49%) but were lower for HMA (13%). Median OS was uniformly poor across treatments: IC, 6.5 months; VEN + HMA, 6.2 months; and HMA, 6.1 months. For IC, the EFS estimate was 3.7 months; EFS was not reported for VEN + HMA or HMA. The ORR was 41% for IC, 65% for VEN + HMA, and 47% for HMA. DoR was 3.5 months for IC, 5.0 months for VEN + HMA, and was not reported for HMA. CONCLUSIONS: Despite improved responses seen with IC and VEN + HMA compared to HMA, survival was uniformly poor, and clinical benefits were limited across all treatments for patients with newly diagnosed, treatment-naïve TP53m AML, demonstrating a significant need for improved treatment for this difficult-to-treat population.


Assuntos
Leucemia Mieloide Aguda , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Intervalo Livre de Progressão , Mutação , Proteína Supressora de Tumor p53/genética , Estudos Observacionais como Assunto
4.
Clin Lymphoma Myeloma Leuk ; 23(2): 127-137, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36428152

RESUMO

BACKGROUND: The global incidence of myelodysplastic syndromes (MDS) has been estimated as 0.06 to 0.26/100,000. Since their introduction, hypomethylating agents have played a central role in the treatment of MDS, with heterogeneous real-world outcomes. MATERIALS AND METHODS: We assessed and synthesized clinical outcomes of azacitidine (AZA) monotherapy in treatment-naïve patients with higher-risk MDS. A systematic literature review was conducted by searching MEDLINE, Embase, and CENTRAL to identify randomized clinical trials (RCTs) and observational studies, both prospective and retrospective, reporting complete remission (CR), partial remission (PR), overall survival (OS), duration of response (DOR), time-to-response (TTR), and myelosuppressive adverse events (AEs) for patients treated with AZA monotherapy. Noncomparative meta-analyses were used to summarize effects. RESULTS: The search identified 3250 abstracts, of which 34 publications describing 16 studies (5 RCTs, 3 prospective, and 8 retrospective observational) were included. Across all studies, pooled CR was 16%; PR was 6%; Median OS was 16.4 months; median DOR was 10.1 months; median TTR was 4.6 months. Proportions of grade 3/4 anemia and thrombocytopenia AEs were 10% and 30%. CONCLUSIONS: The effectiveness and efficacy of AZA monotherapy-as measured by CR and median OS-was limited. These findings highlight a significant unmet medical need for effective treatments for patients with higher-risk MDS.


Assuntos
Azacitidina , Síndromes Mielodisplásicas , Humanos , Azacitidina/efeitos adversos , Antimetabólitos Antineoplásicos/efeitos adversos , Síndromes Mielodisplásicas/tratamento farmacológico , Resultado do Tratamento , Indução de Remissão
5.
Clin Chem ; 69(2): 189-201, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36576350

RESUMO

BACKGROUND: Nuclear-derived cell-free DNA (cfDNA) molecules in blood plasma are nonrandomly fragmented, bearing a wealth of information related to tissues of origin. DNASE1L3 (deoxyribonuclease 1 like 3) is an important player in shaping the fragmentation of nuclear-derived cfDNA molecules, preferentially generating molecules with 5 CC dinucleotide termini (i.e., 5 CC-end motif). However, the fragment end properties of microbial cfDNA and its clinical implication remain to be explored. METHODS: We performed end motif analysis on microbial cfDNA fragments in plasma samples from patients with sepsis. A sequence context-based normalization method was used to minimize the potential biases for end motif analysis. RESULTS: The end motif profiles of microbial cfDNA appeared to resemble that of nuclear cfDNA (Spearman correlation coefficient: 0.82, P value 0.001). The CC-end motif was the most preferred end motif in microbial cfDNA, suggesting that DNASE1L3 might also play a role in the fragmentation of microbe-derived cfDNA in plasma. Of note, differential end motifs were present between microbial cfDNA originating from infection-causing pathogens (enriched at the CC-end) and contaminating microbial DNA potentially derived from reagents or the environment (nearly random). The use of fragment end signatures allowed differentiation between confirmed pathogens and contaminating microbes, with an area under the receiver operating characteristic curve of 0.99. The performance appeared to be superior to conventional analysis based on microbial cfDNA abundance alone. CONCLUSIONS: The use of fragmentomic features could facilitate the differentiation of underlying contaminating microbes from true pathogens in sepsis. This work demonstrates the potential usefulness of microbial cfDNA fragmentomics in metagenomics analysis.


Assuntos
Ácidos Nucleicos Livres , Sepse , Humanos , DNA/genética , Sepse/diagnóstico , Fragmentação do DNA
6.
Proc Natl Acad Sci U S A ; 119(44): e2209852119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36288287

RESUMO

Cell-free DNA (cfDNA) fragmentation patterns contain important molecular information linked to tissues of origin. We explored the possibility of using fragmentation patterns to predict cytosine-phosphate-guanine (CpG) methylation of cfDNA, obviating the use of bisulfite treatment and associated risks of DNA degradation. This study investigated the cfDNA cleavage profile surrounding a CpG (i.e., within an 11-nucleotide [nt] window) to analyze cfDNA methylation. The cfDNA cleavage proportion across positions within the window appeared nonrandom and exhibited correlation with methylation status. The mean cleavage proportion was ∼twofold higher at the cytosine of methylated CpGs than unmethylated ones in healthy controls. In contrast, the mean cleavage proportion rapidly decreased at the 1-nt position immediately preceding methylated CpGs. Such differential cleavages resulted in a characteristic change in relative presentations of CGN and NCG motifs at 5' ends, where N represented any nucleotide. CGN/NCG motif ratios were correlated with methylation levels at tissue-specific methylated CpGs (e.g., placenta or liver) (Pearson's absolute r > 0.86). cfDNA cleavage profiles were thus informative for cfDNA methylation and tissue-of-origin analyses. Using CG-containing end motifs, we achieved an area under a receiver operating characteristic curve (AUC) of 0.98 in differentiating patients with and without hepatocellular carcinoma and enhanced the positive predictive value of nasopharyngeal carcinoma screening (from 19.6 to 26.8%). Furthermore, we elucidated the feasibility of using cfDNA cleavage patterns to deduce CpG methylation at single CpG resolution using a deep learning algorithm and achieved an AUC of 0.93. FRAGmentomics-based Methylation Analysis (FRAGMA) presents many possibilities for noninvasive prenatal, cancer, and organ transplantation assessment.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Hepáticas , Gravidez , Feminino , Humanos , Ácidos Nucleicos Livres/genética , Biomarcadores Tumorais/genética , Metilação de DNA , Neoplasias Hepáticas/genética , Epigênese Genética , DNA/genética , Citosina , Guanina , Nucleotídeos , Fosfatos
7.
Appl Immunohistochem Mol Morphol ; 30(10): 681-686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36227121

RESUMO

Uroplakin II (UPII) has been shown as a highly specific marker of urothelial carcinoma; however, it can also stain subtypes of apocrine-differentiated breast carcinoma. Given that urothelium and breast epithelium share other common immunohistochemical markers, such as CK7 and GATA3, this can lead to a potential diagnostic pitfall. We stained a cohort of triple-negative breast cancer with UPII. Compared with the diffuse, cytoplasmic staining in urothelial carcinoma, UPII was positive in 38.9% of apocrine carcinoma (7/18) with a course, granular cytoplasmic staining pattern and negative in all nonapocrine triple-negative breast cancer cases. Furthermore, the same staining pattern was present in all apocrine metaplasia of the breast (4/4) and apocrine sweat glands in normal skin (6/6). This distinct subcellular localization of UPII staining in breast carcinoma can offer a potential solution to the above diagnostic pitfall.


Assuntos
Neoplasias Ósseas , Neoplasias da Mama , Carcinoma de Células de Transição , Neoplasias das Glândulas Sudoríparas , Neoplasias de Mama Triplo Negativas , Neoplasias da Bexiga Urinária , Humanos , Feminino , Uroplaquina II , Carcinoma de Células de Transição/diagnóstico , Imuno-Histoquímica , Neoplasias da Bexiga Urinária/patologia , Biomarcadores Tumorais , Neoplasias das Glândulas Sudoríparas/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Coloração e Rotulagem
8.
PLoS Genet ; 18(7): e1010262, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35793278

RESUMO

Urinary cell-free DNA (ucfDNA) is a potential biomarker for bladder cancer detection. However, the biological characteristics of ucfDNA are not well understood. We explored the roles of deoxyribonuclease 1 (DNASE1) and deoxyribonuclease 1-like 3 (DNASE1L3) in the fragmentation of ucfDNA using mouse models. The deletion of Dnase1 in mice (Dnase1-/-) caused aberrations in ucfDNA fragmentation, including a 24-fold increase in DNA concentration, and a 3-fold enrichment of long DNA molecules, with a relative decrease of fragments with thymine ends and reduction of jaggedness (i.e., the presence of single-stranded protruding ends). In contrast, such changes were not observed in mice with Dnase1l3 deletion (Dnase1l3-/-). These results suggested that DNASE1 was an important nuclease contributing to the ucfDNA fragmentation. Western blot analysis revealed that the concentration of DNASE1 protein was higher in urine than DNASE1L3. The native-polyacrylamide gel electrophoresis zymogram showed that DNASE1 activity in urine was higher than that in plasma. Furthermore, the proportion of ucfDNA fragment ends within DNase I hypersensitive sites (DHSs) was significantly increased in Dnase1-deficient mice. In humans, patients with bladder cancer had lower proportions of ucfDNA fragment ends within the DHSs when compared with participants without bladder cancer. The area under the curve (AUC) for differentiating patients with and without bladder cancer was 0.83, suggesting the analysis of ucfDNA fragmentation in the DHSs may have potential for bladder cancer detection. This work revealed the intrinsic links between the nucleases in urine and ucfDNA fragmentomics.


Assuntos
Ácidos Nucleicos Livres , Neoplasias da Bexiga Urinária , Animais , Ácidos Nucleicos Livres/genética , DNA/genética , Desoxirribonuclease I/genética , Desoxirribonuclease I/metabolismo , Endodesoxirribonucleases/genética , Endonucleases , Humanos , Camundongos , Camundongos Knockout , Neoplasias da Bexiga Urinária/genética
9.
Clin Chem ; 68(7): 917-926, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35587043

RESUMO

BACKGROUND: Jagged ends of plasma DNA are a recently recognized class of fragmentomic markers for cell-free DNA, reflecting the activity of nucleases. A number of recent studies have also highlighted the importance of jagged ends in the context of pregnancy and oncology. However, knowledge regarding the generation of jagged ends is incomplete. METHODS: Jaggedness of plasma DNA was analyzed based on Jag-seq, which utilized the differential methylation signals introduced by the DNA end-repair process. We investigated the jagged ends in plasma DNA using mouse models by deleting the deoxyribonuclease 1 (Dnase1), DNA fragmentation factor subunit beta (Dffb), or deoxyribonuclease 1 like 3 (Dnase1l3) gene. RESULTS: Aberrations in the profile of plasma DNA jagged ends correlated with the type of nuclease that had been genetically deleted, depending on nucleosomal structures. The deletion of Dnase1l3 led to a significant reduction of jaggedness for those plasma DNA molecules involving more than 1 nucleosome (e.g., size ranges 240-290 bp, 330-380 bp, and 420-470 bp). However, less significant effects of Dnase1 and Dffb deletions were observed regarding different sizes of DNA fragments. Interestingly, the aberration in plasma DNA jagged ends related to multinucleosomes was observed in human subjects with familial systemic lupus erythematosus with Dnase1l3 deficiency and human subjects with sporadic systemic lupus erythematosus. CONCLUSIONS: Detailed understanding of the relationship between nuclease and plasma DNA jaggedness has opened up avenues for biomarker development.


Assuntos
Ácidos Nucleicos Livres , Lúpus Eritematoso Sistêmico , Animais , Biomarcadores , Ácidos Nucleicos Livres/genética , DNA/genética , Desoxirribonucleases/genética , Endodesoxirribonucleases/genética , Feminino , Humanos , Lúpus Eritematoso Sistêmico/genética , Camundongos , Nucleossomos/genética , Gravidez
11.
JCI Insight ; 7(8)2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35451374

RESUMO

Cell-free extrachromosomal circular DNA (eccDNA) as a distinct topological form from linear DNA has recently gained increasing research interest, with possible clinical applications as a class of biomarkers. In this study, we aimed to explore the relationship between nucleases and eccDNA characteristics in plasma. By using knockout mouse models with deficiencies in deoxyribonuclease 1 (DNASE1) or deoxyribonuclease 1 like 3 (DNASE1L3), we found that cell-free eccDNA in Dnase1l3-/- mice exhibited larger size distributions than that in wild-type mice. Such size alterations were not found in tissue eccDNA of either Dnase1-/- or Dnase1l3-/- mice, suggesting that DNASE1L3 could digest eccDNA extracellularly but did not seem to affect intracellular eccDNA. Using a mouse pregnancy model, we observed that in Dnase1l3-/- mice pregnant with Dnase1l3+/- fetuses, the eccDNA in the maternal plasma was shorter compared with that of Dnase1l3-/- mice carrying Dnase1l3-/- fetuses, highlighting the systemic effects of circulating fetal DNASE1L3 degrading the maternal eccDNA extracellularly. Furthermore, plasma eccDNA in patients with DNASE1L3 mutations also exhibited longer size distributions than that in healthy controls. Taken together, this study provided a hitherto missing link between nuclease activity and the biological manifestations of eccDNA in plasma, paving the way for future biomarker development of this special form of DNA molecules.


Assuntos
DNA , Feto , Animais , DNA Circular/genética , Desoxirribonucleases/genética , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Feminino , Feto/metabolismo , Humanos , Camundongos , Camundongos Knockout , Gravidez
12.
Lab Invest ; 102(8): 814-825, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35437316

RESUMO

As the coronavirus disease 2019 (COVID-19) pandemic evolves, much evidence implicates the heart as a critical target of injury in patients. The mechanism(s) of cardiac involvement has not been fully elucidated, although evidence of direct virus-mediated injury, thromboembolism with ischemic complications, and cytokine storm has been reported. We examined suggested mechanisms of COVID-19-associated heart failure in 21 COVID-19-positive decedents, obtained through standard autopsy procedure, compared to clinically matched controls and patients with various etiologies of viral myocarditis. We developed a custom tissue microarray using regions of pathological interest and interrogated tissues via immunohistochemistry and in situ hybridization. Severe acute respiratory syndrome coronavirus 2 was detected in 16/21 patients, in cardiomyocytes, the endothelium, interstitial spaces, and percolating adipocytes within the myocardium. Virus detection typically corresponded with troponin depletion and increased cleaved caspase-3. Indirect mechanisms of injury-venous and arterial thromboses with associated vasculitis including a mixed inflammatory infiltrate-were also observed. Neutrophil extracellular traps (NETs) were present in the myocardium of all COVID-19 patients, regardless of injury degree. Borderline myocarditis (inflammation without associated myocyte injury) was observed in 19/21 patients, characterized by a predominantly mononuclear inflammatory infiltrate. Edema, inflammation of percolating adipocytes, lymphocytic aggregates, and large septal masses of inflammatory cells and platelets were observed as defining features, and myofibrillar damage was evident in all patients. Collectively, COVID-19-associated cardiac injury was multifactorial, with elevated levels of NETs and von Willebrand factor as defining features of direct and indirect viral injury.


Assuntos
COVID-19 , Miocardite , Autopsia , COVID-19/complicações , Humanos , Inflamação , Miócitos Cardíacos
13.
Mol Ther ; 30(7): 2505-2521, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35443935

RESUMO

Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative neoplasia that lacks effective targeted chemotherapies. Clinically, JMML manifests as monocytic leukocytosis, splenomegaly with consequential thrombocytopenia. Most commonly, patients have gain-of-function (GOF) oncogenic mutations in PTPN11 (SHP2), leading to Erk and Akt hyperactivation. Mechanism(s) involved in co-regulation of Erk and Akt in the context of GOF SHP2 are poorly understood. Here, we show that Bruton's tyrosine kinase (BTK) is hyperphosphorylated in GOF Shp2-bearing cells and utilizes B cell adaptor for PI3K to cooperate with p110δ, the catalytic subunit of PI3K. Dual inhibition of BTK and p110δ reduces the activation of both Erk and Akt. In vivo, individual targeting of BTK or p110δ in a mouse model of human JMML equally reduces monocytosis and splenomegaly; however, the combined treatment results in a more robust inhibition and uniquely rescues anemia and thrombocytopenia. RNA-seq analysis of drug-treated mice showed a profound reduction in the expression of genes associated with leukemic cell migration and inflammation, leading to correction in the infiltration of leukemic cells in the lung, liver, and spleen. Remarkably, in a patient derived xenograft model of JMML, leukemia-initiating stem and progenitor cells were potently inhibited in response to the dual drug treatment.


Assuntos
Leucemia Mielomonocítica Juvenil , Trombocitopenia , Tirosina Quinase da Agamaglobulinemia/genética , Animais , Humanos , Leucemia Mielomonocítica Juvenil/genética , Leucemia Mielomonocítica Juvenil/metabolismo , Leucemia Mielomonocítica Juvenil/terapia , Camundongos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Esplenomegalia/genética , Células-Tronco/metabolismo
14.
NPJ Genom Med ; 7(1): 14, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35197474

RESUMO

Single-stranded ends of double-stranded DNA (jagged ends) are more abundant in urinary DNA than in plasma DNA. However, the lengths of jagged ends in urinary DNA remained undetermined, as a previous method used for urinary DNA jagged end sequencing analysis (Jag-seq) relied on unmethylation at CpG sites, limiting the resolution. Here, we performed high-resolution Jag-seq analysis using methylation at non-CpG cytosine sites, allowing determination of exact length of jagged ends. The urinary DNA bore longer jagged ends (~26-nt) than plasma DNA (~17-nt). The jagged end length distribution displayed 10-nt periodicities in urinary DNA, which were much less observable in plasma DNA. Amplitude of the 10-nt periodicities increased in patients with renal cell carcinoma. Heparin treatment of urine diminished the 10-nt periodicities. The urinary DNA jagged ends often extended into nucleosomal cores, suggesting potential interactions with histones. This study has thus advanced our knowledge of jagged ends in urine DNA.

15.
Genome Res ; 31(11): 2008-2021, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34470801

RESUMO

The effects of DNASE1L3 or DNASE1 deficiency on cell-free DNA (cfDNA) methylation were explored in plasma of mice deficient in these nucleases and in DNASE1L3-deficient humans. Compared to wild-type cfDNA, cfDNA in DNASE1L3-deficient mice was significantly hypomethylated, while cfDNA in DNASE1-deficient mice was hypermethylated. The cfDNA hypomethylation in DNASE1L3-deficient mice was due to increased fragmentation and representation from open chromatin regions (OCRs) and CpG islands (CGIs). These findings were absent in DNASE1-deficient mice, demonstrating the preference of DNASE1 to cleave in hypomethylated OCRs and CGIs. We also observed a substantial decrease of fragment ends at methylated CpGs in the absence of DNASE1L3, thereby demonstrating that DNASE1L3 prefers to cleave at methylated CpGs. Furthermore, we found that methylation levels of cfDNA varied by fragment size in a periodic pattern, with cfDNA of specific sizes being more hypomethylated and enriched for OCRs and CGIs. These findings were confirmed in DNASE1L3-deficient human cfDNA. Thus, we have found that nuclease-mediated cfDNA fragmentation markedly affects cfDNA methylation level on a genome-wide scale. This work provides a foundational understanding of the relationship between methylation, nuclease biology, and cfDNA fragmentation.


Assuntos
Ácidos Nucleicos Livres , Fragmentação do DNA , Endodesoxirribonucleases , Animais , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/metabolismo , Cromatina , Ilhas de CpG/genética , Metilação de DNA , Endodesoxirribonucleases/genética , Humanos , Camundongos
16.
Leuk Lymphoma ; 62(12): 2915-2920, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34319205

RESUMO

Idelalisib is associated with increased occurrence of immune-related adverse events (irAEs). Clinical observations suggest a correlation between immune checkpoint inhibitor-induced irAEs and survival outcomes in patients with solid tumors; however, this relationship in hematologic malignancies is not well understood. In a post hoc analysis of 3 registrational trials, we explored the relationship between Grade ≥3 diarrhea/colitis and alanine/aspartate transaminase (ALT/AST) elevation incidences and efficacy endpoints in patients with indolent non-Hodgkin lymphoma (iNHL), follicular lymphoma (FL), and chronic lymphocytic leukemia treated with idelalisib. Grade ≥3 diarrhea/colitis was associated with higher overall response rate (ORR) and longer progression-free survival (PFS) for all subgroups. Grade ≥3 ALT/AST elevations were associated with improved duration of response and overall survival for all subgroups and improved ORR and PFS for patients with FL or iNHL. Our analysis in hematologic malignancies showed a trend correlating idelalisib-induced Grade ≥3 irAEs with improved efficacy.


Assuntos
Colite , Neoplasias Hematológicas , Leucemia Linfocítica Crônica de Células B , Linfoma Folicular , Linfoma não Hodgkin , Colite/induzido quimicamente , Colite/tratamento farmacológico , Diarreia/induzido quimicamente , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma Folicular/tratamento farmacológico , Linfoma não Hodgkin/patologia , Purinas , Quinazolinonas/efeitos adversos
17.
Clin Lymphoma Myeloma Leuk ; 21(5): e432-e448, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33516721

RESUMO

BACKGROUND: Idelalisib is a phosphatidylinositol 3-kinase δ inhibitor approved for relapsed/refractory follicular lymphoma, a type of indolent non-Hodgkin lymphoma (iNHL), and chronic lymphocytic leukemia (CLL). Idelalisib-triggered adverse events (AEs) may be managed with treatment interruption and/or dose reduction, potentially extending therapy duration and increasing the likelihood of continued response. PATIENTS AND METHODS: Post hoc analyses were conducted to evaluate clinical outcomes after AE-induced idelalisib interruption for 125 patients with iNHL and 283 with CLL. RESULTS: Progression-free survival (PFS) was longer for patients with iNHL who experienced ≥ 2 interruptions versus those with 0 interruptions who discontinued idelalisib or study because of AEs (hazard ratio 0.33; P = .0212). Both PFS and overall survival were longer for patients with CLL with ≥ 2 interruptions versus 0 interruptions in those who discontinued therapy because of an AE (hazard ratio PFS 0.50, overall survival 0.41; P < .005). Clinical benefits persisted for patients with CLL who experienced treatment interruption after receiving idelalisib for ≥ 6 months. Supplementing interruption with dose reduction did not worsen clinical outcomes. However, time off therapy of ≥ 8% may diminish the clinical benefit of treatment interruption. CONCLUSION: Idelalisib interruption and dose reduction were associated with enhanced clinical outcomes for patients with relapsed/refractory iNHL or CLL who experienced an AE, supporting this management strategy when indicated.


Assuntos
Antineoplásicos/efeitos adversos , Redução da Medicação/métodos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Purinas/efeitos adversos , Quinazolinonas/efeitos adversos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Retrospectivos
18.
Br J Haematol ; 192(4): 720-728, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32599655

RESUMO

Comorbidities influence survival in patients with chronic lymphocytic leukaemia (CLL) treated with chemo-immunotherapy or ibrutinib. While idelalisib has been studied in patients with comorbidities, their impact has not been investigated. We analysed 481 patients treated with idelalisib on two randomised trials (NCT01659021 and NCT01539512). Comorbidities were assessed using the Cumulative Illness Risk Scale (CIRS). Patients received idelalisib + anti-CD20 (rituximab or ofatumumab; n = 284) or anti-CD20 alone (n = 197). The median age was 69 years. We found that comorbidities did not significantly affect outcomes of idelalisib therapy. The objective response rate (ORR) was 79·3% versus 85·8%, the median progression-free survival (PFS) was 16·3 versus 19·1 months, and the median overall survival (OS) was 39·8 versus 49·8 months in patients treated with idelalisib who had a CIRS score of >6 versus ≤6, correspondingly. Treatment with idelalisib + anti-CD20 was associated with superior PFS and ORR when compared to anti-CD20 monotherapy in patients who had high comorbidities (CIRS score of >6) or at least one severe comorbidity (median PFS 16·3 vs. 6·9 months and 16·6 vs. 6·5 months; odds ratio 20·1 and 33·2; P < 0·0001). Thus, comorbidities do not portend inferior outcomes in patients with CLL treated with idelalisib in combination with anti-CD20 therapy.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Purinas/uso terapêutico , Quinazolinonas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Comorbidade , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Rituximab/uso terapêutico , Resultado do Tratamento
19.
Am J Hum Genet ; 107(5): 882-894, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33022220

RESUMO

Plasma DNA fragmentomics is an emerging area in cell-free DNA diagnostics and research. In murine models, it has been shown that the extracellular DNase, DNASE1L3, plays a role in the fragmentation of plasma DNA. In humans, DNASE1L3 deficiency causes familial monogenic systemic lupus erythematosus with childhood onset and anti-dsDNA reactivity. In this study, we found that human patients with DNASE1L3 disease-associated gene variations showed aberrations in size and a reduction of a "CC" end motif of plasma DNA. Furthermore, we demonstrated that DNA from DNASE1L3-digested cell nuclei showed a median length of 153 bp with CC motif frequencies resembling plasma DNA from healthy individuals. Adeno-associated virus-based transduction of Dnase1l3 into Dnase1l3-deficient mice restored the end motif profiles to those seen in the plasma DNA of wild-type mice. Our findings demonstrate that DNASE1L3 is an important player in the fragmentation of plasma DNA, which appears to act in a cell-extrinsic manner to regulate plasma DNA size and motif frequency.


Assuntos
DNA/genética , Endodesoxirribonucleases/genética , Lúpus Eritematoso Sistêmico/genética , Mutação , Animais , Estudos de Casos e Controles , DNA/sangue , Fragmentação do DNA , Dependovirus/genética , Dependovirus/metabolismo , Modelos Animais de Doenças , Endodesoxirribonucleases/deficiência , Endodesoxirribonucleases/metabolismo , Terapia Genética , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Lúpus Eritematoso Sistêmico/enzimologia , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Camundongos Transgênicos , Especificidade por Substrato , Transdução Genética
20.
Br J Neurosurg ; : 1-5, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32990057

RESUMO

BACKGROUND: Resection of insular tumours utilising modern neurosurgical techniques has become commonplace since its safety and reduced morbidity was first established. Interest has grown in the cognitive consequences of insula neurosurgery and studies have largely shown postoperative stability or minor decline. Major or widespread improvements in cognitive functioning following resection of insular tumours have not previously been reported. CASE DESCRIPTION: A 34-year-old, left-handed man with a right insular low-grade glioma (LGG) presented with seizures, nausea, altered sensation, poor balance and extensive cognitive decline. Comprehensive neuropsychological assessment highlighted a striking left hemispatial neglect and impairments in attention, working memory, verbal learning and fluency. During an awake craniotomy with functional cortical mapping, he reported intraoperative improvements in hand function and processing speed. Resolution of the neglect and significant improvements in cognition, mood and functioning were observed at follow-up and sustained over several years. CONCLUSIONS: This case highlights that right insular LGGs can cause significant cognitive and functional deficits and that neurosurgery has the potential to alleviate these difficulties to an extent beyond those documented in the extant literature.

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