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1.
NPJ Genom Med ; 9(1): 35, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898085

RESUMO

HPV infections are associated with a fraction of vulvar cancers. Through hybridization capture and DNA sequencing, HPV DNA was detected in five of thirteen vulvar cancers. HPV16 DNA was integrated into human DNA in three of the five. The insertions were in introns of human NCKAP1, C5orf67, and LRP1B. Integrations in NCKAP1 and C5orf67 were flanked by short direct repeats in the human DNA, consistent with HPV DNA insertions at sites of abortive, staggered, endonucleolytic incisions. The insertion in C5orf67 was present as a 36 kbp, human-HPV-hetero-catemeric DNA as either an extrachromosomal circle or a tandem repeat within the human genome. The human circularization/repeat junction was defined at single nucleotide resolution. The integrated viral DNA segments all retained an intact upstream regulatory region and the adjacent viral E6 and E7 oncogenes. RNA sequencing revealed that the only HPV genes consistently transcribed from the integrated viral DNAs were E7 and E6*I. The other two HPV DNA+ tumors had coinfections, but no evidence for integration. HPV-positive and HPV-negative vulvar cancers exhibited contrasting human, global gene expression patterns partially overlapping with previously observed differences between HPV-positive and HPV-negative cervical and oropharyngeal cancers. A substantial fraction of the differentially expressed genes involved immune system function. Thus, transcription and HPV DNA integration in vulvar cancers resemble those in other HPV-positive cancers. This study emphasizes the power of hybridization capture coupled with DNA and RNA sequencing to identify a broad spectrum of HPV types, determine human genome integration status of viral DNAs, and elucidate their structures.

2.
iScience ; 27(4): 109524, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38577109

RESUMO

Homologous recombination (HR) protects replication forks (RFs) and repairs DNA double-strand breaks (DSBs). Within HR, BRCA2 regulates RAD51 via two interaction regions: the BRC repeats to form filaments on single-stranded DNA and exon 27 (Ex27) to stabilize the filament. Here, we identified a RAD51 S181P mutant that selectively disrupted the RAD51-Ex27 association while maintaining interaction with BRC repeat and proficiently forming filaments capable of DNA binding and strand invasion. Interestingly, RAD51 S181P was defective for RF protection/restart but proficient for DSB repair. Our data suggest that Ex27-mediated stabilization of RAD51 filaments is required for the protection of RFs, while it seems dispensable for the repair of DSBs.

3.
Clin Cancer Res ; 30(4): 865-876, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38060213

RESUMO

PURPOSE: The abundance and biological contribution of cancer-associated fibroblasts (CAF) in glioblastoma (GBM) are poorly understood. Here, we aim to uncover its molecular signature, cellular roles, and potential tumorigenesis implications. EXPERIMENTAL DESIGN: We first applied single-cell RNA sequencing (RNA-seq) and bioinformatics analysis to identify and characterize stromal cells with CAF transcriptomic features in human GBM tumors. Then, we performed functional enrichment analysis and in vitro assays to investigate their interactions with malignant GBM cells. RESULTS: We found that CAF abundance was low but significantly correlated with tumor grade, poor clinical outcome, and activation of extracellular matrix remodeling using three large cohorts containing bulk RNA-seq data and clinical information. Proteomic analysis of a GBM-derived CAF line and its secretome revealed fibronectin (FN1) as a critical candidate factor mediating CAF functions. This was validated using in vitro cellular models, which demonstrated that CAF-conditioned media and recombinant FN1 could facilitate the migration and invasion of GBM cells. In addition, we showed that CAFs were more abundant in the mesenchymal-like state (or subtype) than in other states of GBMs. Interestingly, cell lines resembling the proneural state responded to the CAF signaling better for the migratory and invasive phenotypes. CONCLUSIONS: Overall, this study characterized the molecular features and functional impacts of CAFs in GBM, alluding to novel cell interactions mediated by CAFs in the GBM microenvironment.


Assuntos
Fibroblastos Associados a Câncer , Glioblastoma , Humanos , Fibroblastos Associados a Câncer/metabolismo , Glioblastoma/patologia , Linhagem Celular Tumoral , Proteômica , Movimento Celular/genética , Microambiente Tumoral/genética , Fibroblastos/metabolismo
4.
Nat Protoc ; 19(2): 487-516, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37996541

RESUMO

Somatic mutations are the cause of cancer and have been implicated in other, noncancerous diseases and aging. While clonally expanded mutations can be studied by deep sequencing of bulk DNA, very few somatic mutations expand clonally, and most are unique to each cell. We describe a detailed protocol for single-cell whole-genome sequencing to discover and analyze somatic mutations in tissues and organs. The protocol comprises single-cell multiple displacement amplification (SCMDA), which ensures efficiency and high fidelity in amplification, and the SCcaller software tool to call single-nucleotide variations and small insertions and deletions from the sequencing data by filtering out amplification artifacts. With SCMDA and SCcaller at its core, this protocol describes a complete procedure for the comprehensive analysis of somatic mutations in a single cell, covering (1) single-cell or nucleus isolation, (2) single-cell or nucleus whole-genome amplification, (3) library preparation and sequencing, and (4) computational analyses, including alignment, variant calling, and mutation burden estimation. Methods are also provided for mutation annotation, hotspot discovery and signature analysis. The protocol takes 12-15 h from single-cell isolation to library preparation and 3-7 d of data processing. Compared with other single-cell amplification methods or single-molecular sequencing, it provides high genomic coverage, high accuracy in single-nucleotide variation and small insertions and deletion calling from the same single-cell genome, and fewer processing steps. SCMDA and SCcaller require basic experience in molecular biology and bioinformatics. The protocol can be utilized for studying mutagenesis and genome mosaicism in normal and diseased human and animal tissues under various conditions.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Nucleotídeos , Animais , Humanos , Mutação , Sequenciamento Completo do Genoma , Mutagênese , Análise de Sequência de DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos
5.
Chromosome Res ; 31(4): 32, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910282

RESUMO

This review investigates the role of aneuploidy and chromosome instability (CIN) in the aging brain. Aneuploidy refers to an abnormal chromosomal count, deviating from the normal diploid set. It can manifest as either a deficiency or excess of chromosomes. CIN encompasses a broader range of chromosomal alterations, including aneuploidy as well as structural modifications in DNA. We provide an overview of the state-of-the-art methodologies utilized for studying aneuploidy and CIN in non-tumor somatic tissues devoid of clonally expanded populations of aneuploid cells.CIN and aneuploidy, well-established hallmarks of cancer cells, are also associated with the aging process. In non-transformed cells, aneuploidy can contribute to functional impairment and developmental disorders. Despite the importance of understanding the prevalence and specific consequences of aneuploidy and CIN in the aging brain, these aspects remain incompletely understood, emphasizing the need for further scientific investigations.This comprehensive review consolidates the present understanding, addresses discrepancies in the literature, and provides valuable insights for future research efforts.


Assuntos
Aneuploidia , Neoplasias , Animais , Humanos , Instabilidade Cromossômica , Aberrações Cromossômicas , Encéfalo , Cromossomos , Neoplasias/genética , Mamíferos/genética
6.
Cancer Chemother Pharmacol ; 92(6): 501-510, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37725113

RESUMO

PURPOSE: The clinical outcome and the efficacy of chemotherapy in pancreatic cancer patients with BRCA1/2 Variants of Unknown Significance (VUS) is unknown. We explored the effects of chemotherapy with or without Platinum in non metastatic and metastatic pancreatic cancer patients with BRCA1/2 VUS. METHODS: A retrospective analysis of non-metastatic or metastatic pancreatic cancer patients with gBRCA1/2 VUS treated in 13 Italian centers between November 2015 and December 2020 was performed. All patients were assessed for toxicity and RECIST 1.1 response. Metastatic patients were evaluated for survival outcome. RESULTS: 30 pancreatic cancer patients with gBRCA1/2 VUS were considered: 20 were M+ and 10 were non-M+. Pl-CT was recommended to 16 patients: 10 M+ (6 FOLFIRINOX and 4 PAXG) and 6 non-M+ (3 FOLFIRINOX and 3 PAXG); 11 patients received Nabpaclitaxel-Gemcitabine (AG; 8 M+) and 3 patients (2 M+) were treated with Gemcitabine (G). The RECIST 1.1 response rate was 27% for AG and 44% for Pl-CT (22% for (m) FOLFIRINOX and 71% PAXG). 1 year Progression-Free Survival was 37.5% for patients treated with AG and 33% in the Pl-CT subgroup. Median Overall Survival (OS) was 23.5 months for patients treated with AG and 14 months for the Pl-CT subgroup. 1 Year and 2 Year OS were numerically better for AG (1 Year OS: 75% vs 60% and 2 Year OS: 50% and 20% in AG and Pl-CT subgroups, respectively) as well. CONCLUSIONS: Pl-CT does not seem to be associated with a better outcome compared to AG chemotherapy in PDAC patients with BRCA 1/2 VUS.


Assuntos
Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Genes BRCA2 , Proteína BRCA1/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Retrospectivos , Proteína BRCA2/genética , Neoplasias Pancreáticas
7.
bioRxiv ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37398007

RESUMO

We report here that expression of the ribosomal protein, RPL22, is frequently reduced in human myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML); reduced RPL22 expression is associated with worse outcomes. Mice null for Rpl22 display characteristics of an MDS-like syndrome and develop leukemia at an accelerated rate. Rpl22-deficient mice also display enhanced hematopoietic stem cell (HSC) self-renewal and obstructed differentiation potential, which arises not from reduced protein synthesis but from increased expression of the Rpl22 target, ALOX12, an upstream regulator of fatty acid oxidation (FAO). The increased FAO mediated by Rpl22-deficiency also persists in leukemia cells and promotes their survival. Altogether, these findings reveal that Rpl22 insufficiency enhances the leukemia potential of HSC via non-canonical de-repression of its target, ALOX12, which enhances FAO, a process that may serve as a therapeutic vulnerability of Rpl22 low MDS and AML leukemia cells. Highlights: RPL22 insufficiency is observed in MDS/AML and is associated with reduced survivalRpl22-deficiency produces an MDS-like syndrome and facilitates leukemogenesisRpl22-deficiency does not impair global protein synthesis by HSCRpl22 controls leukemia cell survival by non-canonical regulation of lipid oxidation eTOC: Rpl22 controls the function and transformation potential of hematopoietic stem cells through effects on ALOX12 expression, a regulator of fatty acid oxidation.

8.
bioRxiv ; 2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37398172

RESUMO

Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle that determines migratory strategies. However, how the nucleus crosstalks with invadopodia is little known. Here, we report that the oncogenic septin 9 isoform 1 (SEPT9_i1) is a component of breast cancer invadopodia. SEPT9_i1 depletion diminishes invadopodia formation and the clustering of invadopodia precursor components TKS5 and cortactin. This phenotype is characterized by deformed nuclei, and nuclear envelopes with folds and grooves. We show that SEPT9_i1 localizes to the nuclear envelope and juxtanuclear invadopodia. Moreover, exogenous lamin A rescues nuclear morphology and juxtanuclear TKS5 clusters. Importantly, SEPT9_i1 is required for the amplification of juxtanuclear invadopodia, which is induced by the epidermal growth factor. We posit that nuclei of low deformability favor the formation of juxtanuclear invadopodia in a SEPT9_i1-dependent manner, which functions as a tunable mechanism for overcoming ECM impenetrability. Highlights: The oncogenic SEPT9_i1 is enriched in breast cancer invadopodia in 2D and 3D ECMSEPT9_i1 promotes invadopodia precursor clustering and invadopodia elongationSEPT9_i1 localizes to the nuclear envelope and reduces nuclear deformabilitySEPT9_i1 is required for EGF-induced amplification of juxtanuclear invadopodia. eTOC Blurb: Invadopodia promote the invasion of metastatic cancers. The nucleus is a mechanosensory organelle that determines migratory strategies, but how it crosstalks with invadopodia is unknown. Okletey et al show that the oncogenic isoform SEPT9_i1 promotes nuclear envelope stability and the formation of invadopodia at juxtanuclear areas of the plasma membrane.

9.
Cell Rep ; 42(8): 112893, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37516960

RESUMO

Invadopodia are extracellular matrix (ECM) degrading structures, which promote cancer cell invasion. The nucleus is increasingly viewed as a mechanosensory organelle that determines migratory strategies. However, how the nucleus crosstalks with invadopodia is little known. Here, we report that the oncogenic septin 9 isoform 1 (SEPT9_i1) is a component of breast cancer invadopodia. SEPT9_i1 depletion diminishes invadopodium formation and the clustering of the invadopodium precursor components TKS5 and cortactin. This phenotype is characterized by deformed nuclei and nuclear envelopes with folds and grooves. We show that SEPT9_i1 localizes to the nuclear envelope and juxtanuclear invadopodia. Moreover, exogenous lamin A rescues nuclear morphology and juxtanuclear TKS5 clusters. Importantly, SEPT9_i1 is required for the amplification of juxtanuclear invadopodia, which is induced by the epidermal growth factor. We posit that nuclei of low deformability favor the formation of juxtanuclear invadopodia in a SEPT9_i1-dependent manner, which functions as a tunable mechanism for overcoming ECM impenetrability.


Assuntos
Neoplasias da Mama , Podossomos , Humanos , Feminino , Septinas/metabolismo , Podossomos/metabolismo , Isoformas de Proteínas/metabolismo , Neoplasias da Mama/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Linhagem Celular Tumoral , Invasividade Neoplásica
10.
Sci Adv ; 9(8): eade8222, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36812307

RESUMO

Myelodysplastic syndrome (MDS) is a clonal malignancy arising in hematopoietic stem cells (HSCs). The mechanisms of MDS initiation in HSCs are still poorly understood. The phosphatidylinositol 3-kinase (PI3K)/AKT pathway is frequently activated in acute myeloid leukemia, but in MDS, PI3K/AKT is often down-regulated. To determine whether PI3K down-regulation can perturb HSC function, we generated a triple knockout (TKO) mouse model with Pik3ca, Pik3cb, and Pik3cd deletion in hematopoietic cells. Unexpectedly, PI3K deficiency caused cytopenias, decreased survival, and multilineage dysplasia with chromosomal abnormalities, consistent with MDS initiation. TKO HSCs exhibit impaired autophagy, and pharmacologic autophagy induction improved HSC differentiation. Using intracellular LC3 and P62 flow cytometry and transmission electron microscopy, we also observed abnormal autophagic degradation in patient MDS HSCs. Therefore, we have uncovered an important protective role for PI3K in maintaining autophagic flux in HSCs to preserve the balance between self-renewal and differentiation and to prevent MDS initiation.


Assuntos
Síndromes Mielodisplásicas , Fosfatidilinositol 3-Quinases , Camundongos , Animais , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Diferenciação Celular , Camundongos Knockout
11.
Dis Model Mech ; 15(11)2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36444717

RESUMO

Aneuploidy, the gain or loss of chromosomes, is the cause of birth defects and miscarriage and is almost ubiquitous in cancer cells. Mosaic aneuploidy causes cancer predisposition, as well as age-related disorders. Despite the cell-intrinsic mechanisms that prevent aneuploidy, sporadic aneuploid cells do arise in otherwise normal tissues. These aneuploid cells can differ from normal cells in the copy number of specific dose-sensitive genes, and may also experience proteotoxic stress associated with mismatched expression levels of many proteins. These differences may mark aneuploid cells for recognition and elimination. The ribosomal protein gene dose in aneuploid cells could be important because, in Drosophila, haploinsufficiency for these genes leads to elimination by the process of cell competition. Constitutive haploinsufficiency for human ribosomal protein genes causes Diamond Blackfan anemia, but it is not yet known whether ribosomal protein gene dose contributes to aneuploid cell elimination in mammals. In this Review, we discuss whether cell competition on the basis of ribosomal protein gene dose is a tumor suppressor mechanism, reducing the accumulation of aneuploid cells. We also discuss how this might relate to the tumor suppressor function of p53 and the p53-mediated elimination of aneuploid cells from murine embryos, and how cell competition defects could contribute to the cancer predisposition of Diamond Blackfan anemia.


Assuntos
Anemia de Diamond-Blackfan , Competição entre as Células , Humanos , Animais , Camundongos , Anemia de Diamond-Blackfan/genética , Proteína Supressora de Tumor p53/genética , Ribossomos , Aneuploidia , Proteínas Ribossômicas/genética , Drosophila , Mamíferos
12.
Sci Immunol ; 7(74): eabl3795, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35984892

RESUMO

A diet rich in saturated fat and carbohydrates causes low-grade chronic inflammation in several organs, including the liver, ultimately driving nonalcoholic steatohepatitis. In this setting, environment-driven lipotoxicity and glucotoxicity induce liver damage, which promotes dendritic cell activation and generates a major histocompatibility complex class II (MHC-II) immunopeptidome enriched with peptides derived from proteins involved in cellular metabolism, oxidative phosphorylation, and the stress responses. Here, we demonstrated that lipotoxicity and glucotoxicity, as driven by a high-fat and high-fructose (HFHF) diet, promoted MHC-II presentation of nested T and B cell epitopes from protein disulfide isomerase family A member 3 (PDIA3), which is involved in immunogenic cell death. Increased MHC-II presentation of PDIA3 peptides was associated with antigen-specific proliferation of hepatic CD4+ immune infiltrates and isotype switch of anti-PDIA3 antibodies from IgM to IgG3, indicative of cellular and humoral PDIA3 autoreactivity. Passive transfer of PDIA3-specific T cells or PDIA3-specific antibodies also exacerbated hepatocyte death, as determined by increased hepatic transaminases detected in the sera of mice subjected to an HFHF but not control diet. Increased humoral responses to PDIA3 were also observed in patients with chronic inflammatory liver conditions, including autoimmune hepatitis, primary biliary cholangitis, and type 2 diabetes. Together, our data indicated that metabolic insults caused by an HFHF diet elicited liver damage and promoted pathogenic immune autoreactivity driven by T and B cell PDIA3 epitopes.


Assuntos
Autoimunidade , Diabetes Mellitus Tipo 2 , Fígado , Isomerases de Dissulfetos de Proteínas , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Epitopos , Antígenos de Histocompatibilidade Classe II , Fígado/patologia , Camundongos , Peptídeos , Isomerases de Dissulfetos de Proteínas/imunologia , Isomerases de Dissulfetos de Proteínas/metabolismo
13.
J Clin Invest ; 132(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025760

RESUMO

Inherited germline mutations in the breast cancer gene 1 (BRCA1) or BRCA2 genes (herein BRCA1/2) greatly increase the risk of breast and ovarian cancer, presumably by elevating somatic mutational errors as a consequence of deficient DNA repair. However, this has never been directly demonstrated by a comprehensive analysis of the somatic mutational landscape of primary, noncancer, mammary epithelial cells of women diagnosed with pathogenic BRCA1/2 germline mutations. Here, we used an accurate, single-cell whole-genome sequencing approach to first show that telomerized primary mammary epithelial cells heterozygous for a highly penetrant BRCA1 variant displayed a robustly elevated mutation frequency as compared with their isogenic control cells. We then demonstrated a small but statistically significant increase in mutation frequency in mammary epithelial cells isolated from the breast of BRCA1/2 mutation carriers as compared with those obtained from age-matched controls with no genetically increased risk for breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células Epiteliais/patologia , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Mutação , Neoplasias Ovarianas/patologia , Análise de Célula Única
14.
J Smok Cessat ; 2021: 1894160, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956404

RESUMO

BACKGROUND: Persons with HIV (PWH) smoke cigarettes at much higher rates than the general population in the US, and smoking is now the leading cause of death in US PWH. Efforts to control the tobacco use epidemic in PWH have met with limited success, and the factors associated with successful cessation are not well delineated. There is a particular dearth of knowledge regarding PWH ex-smokers who have successfully quit smoking cigarettes for the long term. METHODS: We pooled data from three separate sources of PWH smokers and ex-smokers (reporting complete abstinence for ≥ one year with biochemical verification at the time of data collection) from New York City, collected sociodemographic and behavioral information from them in structured interviews, and obtained their DNA samples. Univariate and rigorous multivariate analytic strategies were employed to determine the sociobehavioral and genetic factors that distinguished PWH smokers from ex-smokers. RESULTS: We compared 142 current/recent smokers to 52 biochemically confirmed ex-smokers. The mean age of the participants was 53.3 ± 9.9 years, 49.5% were female, and 76.3% were Black/African American. Successful quitters had significantly lower anxiety scores and were less likely to report hazardous alcohol use or to use marijuana or cocaine. On multivariate analysis utilizing a conservative analytic approach, of 156 single nucleotide variants (SNV) within 12 a priori candidate genes, only the 37148248 T->C variant of gene SLC25A21 on chromosome 14 was associated with long-term cessation. CONCLUSIONS: In this study, we report behavioral variables associated with long-term abstinence in PWH ex-smokers, and we also report the first genetic correlation of successful cessation in a PWH population yet described.

15.
Proteomics ; 21(19): e2100155, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34409731

RESUMO

Septins are a family of multimeric GTP-binding proteins, which are abnormally expressed in cancer. Septin 9 (SEPT9) is an essential and ubiquitously expressed septin with multiple isoforms, which have differential expression patterns and effects in breast cancer cells. It is unknown, however, if SEPT9 isoforms associate with different molecular networks and functions. Here, we performed a proteomic screen in MCF-7 breast cancer cells to identify the interactome of GFP-SEPT9 isoforms 1, 4 and 5, which vary significantly in their N-terminal extensions. While all three isoforms associated with SEPT2 and SEPT7, the truncated SEPT9_i4 and SEPT9_i5 interacted with septins of the SEPT6 group more promiscuously than SEPT9_i1, which bound predominately SEPT8. Spatial mapping and functional clustering of non-septin partners showed isoform-specific differences in interactions with proteins of distinct subcellular organelles (e.g., nuclei, centrosomes, cilia) and functions such as cell signalling and ubiquitination. The interactome of the full length SEPT9_i1 was more enriched in cytoskeletal regulators, while the truncated SEPT9_i4 and SEPT9_i5 exhibited preferential and isoform-specific interactions with nuclear, signalling, and ubiquitinating proteins. These data provide evidence for isoform-specific interactions, which arise from truncations in the N-terminal extensions of SEPT9, and point to novel roles in the pathogenesis of breast cancer.


Assuntos
Neoplasias da Mama , Septinas , Feminino , Perfilação da Expressão Gênica , Humanos , Células MCF-7 , Isoformas de Proteínas/genética , Proteômica , Septinas/genética , Septinas/metabolismo
16.
Genome Med ; 13(1): 93, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34034815

RESUMO

BACKGROUND: Many carcinomas have recurrent chromosomal aneuploidies specific to the tissue of tumor origin. The reason for this specificity is not completely understood. METHODS: In this study, we looked at the frequency of chromosomal arm gains and losses in different cancer types from the The Cancer Genome Atlas (TCGA) and compared them to the mean gene expression of each chromosome arm in corresponding normal tissues of origin from the Genotype-Tissue Expression (GTEx) database, in addition to the distribution of tissue-specific oncogenes and tumor suppressors on different chromosome arms. RESULTS: This analysis revealed a complex picture of factors driving tumor karyotype evolution in which some recurrent chromosomal copy number reflect the chromosome arm-wide gene expression levels of the their normal tissue of tumor origin. CONCLUSIONS: We conclude that the cancer type-specific distribution of chromosomal arm gains and losses is potentially "hardwiring" gene expression levels characteristic of the normal tissue of tumor origin, in addition to broadly modulating the expression of tissue-specific tumor driver genes.


Assuntos
Aneuploidia , Biomarcadores Tumorais , Mapeamento Cromossômico , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Algoritmos , Análise por Conglomerados , Biologia Computacional/métodos , Metilação de DNA , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Humanos , Mutação , Oncogenes , Especificidade de Órgãos/genética
17.
Cancer Cell ; 39(4): 529-547.e7, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33667384

RESUMO

MDMX is overexpressed in the vast majority of patients with acute myeloid leukemia (AML). We report that MDMX overexpression increases preleukemic stem cell (pre-LSC) number and competitive advantage. Utilizing five newly generated murine models, we found that MDMX overexpression triggers progression of multiple chronic/asymptomatic preleukemic conditions to overt AML. Transcriptomic and proteomic studies revealed that MDMX overexpression exerts this function, unexpectedly, through activation of Wnt/ß-Catenin signaling in pre-LSCs. Mechanistically, MDMX binds CK1α and leads to accumulation of ß-Catenin in a p53-independent manner. Wnt/ß-Catenin inhibitors reverse MDMX-induced pre-LSC properties, and synergize with MDMX-p53 inhibitors. Wnt/ß-Catenin signaling correlates with MDMX expression in patients with preleukemic myelodysplastic syndromes and is associated with increased risk of progression to AML. Our work identifies MDMX overexpression as a pervasive preleukemic-to-AML transition mechanism in different genetically driven disease subtypes, and reveals Wnt/ß-Catenin as a non-canonical MDMX-driven pathway with therapeutic potential for progression prevention and cancer interception.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , beta Catenina/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Camundongos , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Proteômica/métodos , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia
18.
BMC Med Genomics ; 13(1): 179, 2020 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256706

RESUMO

BACKGROUND: The Cancer Genome Atlas identified four molecular subgroups of endometrial cancer with survival differences based on whole genome, transcriptomic, and proteomic characterization. Clinically accessible algorithms that reproduce this data are needed. Our aim was to determine if targeted sequencing alone allowed for molecular classification of endometrial cancer. METHODS: Using a custom-designed 156 gene panel, we analyzed 47 endometrial cancers and matching non-tumor tissue. Variants were annotated for pathogenicity and medical records were reviewed for the clinicopathologic variables. Using molecular characteristics, tumors were classified into four subgroups. Group 1 included patients with > 570 unfiltered somatic variants, > 9 cytosine to adenine nucleotide substitutions per sample, and < 1 cytosine to guanine nucleotide substitution per sample. Group 2 included patients with any somatic mutation in MSH2, MSH6, MLH1, PMS2. Group 3 included patients with TP53 mutations without mutation in mismatch repair genes. Remaining patients were classified as group 4. Analyses were performed using SAS 9.4 (SAS Institute Inc., Cary, North Carolina, USA). RESULTS: Endometrioid endometrial cancers had more candidate variants of potential pathogenic interest (median 6 IQR 4.13 vs. 2 IQR 2.3; p < 0.01) than uterine serous cancers. PTEN (82% vs. 15%, p < 0.01) and PIK3CA (74% vs. 23%, p < 0.01) mutations were more frequent in endometrioid than serous carcinomas. TP53 (18% vs. 77%, p < 0.01) mutations were more frequent in serous carcinomas. Visual inspection of the number of unfiltered somatic variants per sample identified six grade 3 endometrioid samples with high tumor mutational burden, all of which demonstrated POLE mutations, most commonly P286R and V411L. Of the grade 3 endometrioid carcinomas, those with POLE mutations were less likely to have risk factors necessitating adjuvant treatment than those with low tumor mutational burden. Targeted sequencing was unable to assign samples to microsatellite unstable, copy number low, and copy number high subgroups. CONCLUSIONS: Targeted sequencing can predict the presence of POLE mutations based on the tumor mutational burden. However, targeted sequencing alone is inadequate to classify endometrial cancers into molecular subgroups identified by The Cancer Genome Atlas.


Assuntos
DNA de Neoplasias/genética , Neoplasias do Endométrio/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Mutação , Proteínas de Neoplasias/genética , Idoso , Carcinoma Endometrioide/genética , Variações do Número de Cópias de DNA , Reparo de Erro de Pareamento de DNA/genética , DNA Polimerase II/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/terapia , Feminino , Humanos , Mutação INDEL , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Segunda Neoplasia Primária/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Polimorfismo de Nucleotídeo Único
19.
J Transl Med ; 18(1): 323, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854748

RESUMO

BACKGROUND: Serum cell-free DNA (cfDNA) holds promise as a non-invasive cancer biomarker. The objective of this study was to evaluate the association of cfDNA concentration with clinicopathologic variables of poor prognosis and overall survival among women with uterine cancer compared to benign cancer-free controls. METHODS: cfDNA was extracted from the serum of 91 women with multiple uterine cancer histologies and 22 post-menopausal controls without cancer. Low molecular weight (LMW) cfDNA was separated from contaminating genomic high molecular weight cfDNA using paramagnetic bead purification and its concentration was measured using fluorometric quantification. Clinicopathologic data was abstracted from the electronic medical record. The association between serum cfDNA concentration, clinicopathologic variables, and overall survival was assessed using linear regression modelling, Cox proportional hazards modelling, and the Kaplan-Meier method. RESULTS: Median total serum cfDNA concentration for the cohort was 69.2 ng/mL (IQR 37.4, 132.3) and median LMW cfDNA concentration was 23.8 ng/mL (IQR 14.9, 44.4). There were no significant differences in total serum cfDNA concentration with any clinicopathologic variables. However, LMW cfDNA concentration was significantly higher in serum of women with cancer (25.8 ng/mL IQR 16.0, 49.6) compared to benign controls (15.5 ng/mL IQR 9.3, 25.8 ng/mL) (p < 0.01). It is also significantly higher among women with early stage cancer than benign controls (p < 0.01). There were also significant associations between LMW cfDNA concentration and stage of cancer (p = 0.01) and histology (p = 0.02). Patients with leiomyosarcoma and carcinosarcoma had higher cfDNA concentrations than those with endometrioid cancer. Over a median follow-up of 51.9 months, 75th percentile for overall survival for women with cancer was 24.0 months. Higher LMW cfDNA concentrations is associated with lower survival among women with cancer (p < 0.01). CONCLUSIONS: Serum LMW cfDNA concentration is associated with overall survival in women with uterine cancer, and it is higher among women with uterine cancer compared to those of controls.


Assuntos
Ácidos Nucleicos Livres , Neoplasias do Endométrio , Neoplasias Uterinas , Feminino , Humanos , Peso Molecular , Prognóstico , Neoplasias Uterinas/genética
20.
Genes Chromosomes Cancer ; 59(2): 84-95, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31407403

RESUMO

Cervical carcinogenesis, the second leading cause of cancer death in women worldwide, is caused by multiple types of human papillomaviruses (HPVs). To investigate a possible role for HPV in a cervical carcinoma that was HPV-negative by PCR testing, we performed HPV DNA hybridization capture plus massively parallel sequencing. This detected a subgenomic, URR-E6-E7-E1 segment of HPV70 DNA, a type not generally associated with cervical cancer, inserted in an intron of the B-cell lymphoma/leukemia 11B (BCL11B) gene in the human genome. Long range DNA sequencing confirmed the virus and flanking BCL11B DNA structures including both insertion junctions. Global transcriptomic analysis detected multiple, alternatively spliced, HPV70-BCL11B, fusion transcripts with fused open reading frames. The insertion and fusion transcripts were present in an intraepithelial precursor phase of tumorigenesis. These results suggest oncogenicity of HPV70, identify novel BCL11B variants with potential oncogenic implications, and underscore the advantages of thorough genomic analyses to elucidate insights into HPV-associated tumorigenesis.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/genética , Sequência de Bases , Carcinogênese/genética , Carcinogênese/metabolismo , DNA Viral/análise , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Pessoa de Meia-Idade , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/metabolismo
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