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1.
ACS ES T Water ; 3(4): 954-962, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37406038

ABSTRACT

The sequencing of human virus genomes from wastewater samples is an efficient method for tracking viral transmission and evolution at the community level. However, this requires the recovery of viral nucleic acids of high quality. We developed a reusable tangential-flow filtration system to concentrate and purify viruses from wastewater for genome sequencing. A pilot study was conducted with 94 wastewater samples from four local sewersheds, from which viral nucleic acids were extracted, and the whole genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was sequenced using the ARTIC V4.0 primers. Our method yielded a high probability (0.9) of recovering complete or near-complete SARS-CoV-2 genomes (>90% coverage at 10× depth) from wastewater when the COVID-19 incidence rate exceeded 33 cases per 100 000 people. The relative abundances of sequenced SARS-CoV-2 variants followed the trends observed from patient-derived samples. We also identified SARS-CoV-2 lineages in wastewater that were underrepresented or not present in the clinical whole-genome sequencing data. The developed tangential-flow filtration system can be easily adopted for the sequencing of other viruses in wastewater, particularly those at low concentrations.

2.
Front Oncol ; 12: 892207, 2022.
Article in English | MEDLINE | ID: mdl-35912202

ABSTRACT

Traditional analysis of genomic data from bulk sequencing experiments seek to group and compare sample cohorts into biologically meaningful groups. To accomplish this task, large scale databases of patient-derived samples, like that of TCGA, have been established, giving the ability to interrogate multiple data modalities per tumor. We have developed a computational strategy employing multimodal integration paired with spectral clustering and modern dimension reduction techniques such as PHATE to provide a more robust method for cancer sub-type classification. Using this integrated approach, we have examined 514 Head and Neck Squamous Carcinoma (HNSC) tumor samples from TCGA across gene-expression, DNA-methylation, and microbiome data modalities. We show that these approaches, primarily developed for single-cell sequencing can be efficiently applied to bulk tumor sequencing data. Our multimodal analysis captures the dynamic heterogeneity, identifies new and refines subtypes of HNSC, and orders tumor samples along well-defined cellular trajectories. Collectively, these results showcase the inherent molecular complexity of tumors and offer insights into carcinogenesis and importance of targeted therapy. Computational techniques as highlighted in our study provide an organic and powerful approach to identify granular patterns in large and noisy datasets that may otherwise be overlooked.

3.
Oncogene ; 39(2): 262-277, 2020 01.
Article in English | MEDLINE | ID: mdl-31477832

ABSTRACT

Head and neck squamous cell carcinoma (HNSCC) is a disease of significant morbidity and mortality and rarely diagnosed in early stages. Despite extensive genetic and genomic characterization, targeted therapeutics and diagnostic markers of HNSCC are lacking due to the inherent heterogeneity and complexity of the disease. Herein, we have generated the global histone mark based epigenomic and transcriptomic cartogram of SCC25, a representative cell type of mesenchymal HNSCC and its normal oral keratinocyte counterpart. Examination of genomic regions marked by differential chromatin states and associated with misregulated gene expression led us to identify SCC25 enriched regulatory sequences and transcription factors (TF) motifs. These findings were further strengthened by ATAC-seq based open chromatin and TF footprint analysis which unearthed Krüppel-like Factor 4 (KLF4) as a potential key regulator of the SCC25 cistrome. We reaffirm the results obtained from in silico and chromatin studies in SCC25 by ChIP-seq of KLF4 and identify ΔNp63 as a co-oncogenic driver of the cancer-specific gene expression milieu. Taken together, our results lead us to propose a model where elevated KLF4 levels sustains the oncogenic state of HNSCC by reactivating repressed chromatin domains at key downstream genes, often by targeting super-enhancers.


Subject(s)
Enhancer Elements, Genetic , Kruppel-Like Transcription Factors/genetics , Squamous Cell Carcinoma of Head and Neck/genetics , Transcriptome/genetics , Cell Line, Tumor , Chromatin/genetics , Epigenomics , Gene Expression Regulation, Neoplastic , Histone Code/genetics , Humans , Kruppel-Like Factor 4 , Regulatory Sequences, Nucleic Acid , Squamous Cell Carcinoma of Head and Neck/pathology , Transcription Factors/genetics
4.
Mol Cancer Res ; 17(1): 250-262, 2019 01.
Article in English | MEDLINE | ID: mdl-30237296

ABSTRACT

Deregulated expression of the transcriptional coactivator with PDZ-binding motif (WWTR1/TAZ) is a common feature of basal-like breast cancer (BLBC). Yet, how oncogenic TAZ regulates cell-cycle progression and proliferation in breast cancer remains poorly understood, and whether TAZ is required for tumor maintenance has not been established. Here, using an integrative oncogenomic approach, TAZ-dependent cellular programs essential for tumor growth and progression were identified. Significantly, TAZ-driven tumor cells required sustained TAZ expression, given that its withdrawal impaired both genesis and maintenance of solid tumors. Moreover, temporal inhibition of TAZ diminished the metastatic burden in established macroscopic pulmonary metastases. Mechanistic investigation revealed that TAZ controls distinct gene profiles that determine cancer cell fate through cell-cycle networks, including a specific, causal role for S-phase kinase-associated protein 2 (SKP2) in mediating the neoplastic state. Together, this study elucidates the molecular events that underpin the role of TAZ in BLBC and link to SKP2, a convergent communication node for multiple cancer signaling pathways, as a key downstream effector molecule. IMPLICATIONS: Understanding the molecular role of TAZ and its link to SKP2, a signaling convergent point and key regulator in BLBC, represents an important step toward the identification of novel therapeutic targets for TAZ-dependent breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Cyclin-Dependent Kinase Inhibitor p27/antagonists & inhibitors , S-Phase Kinase-Associated Proteins/antagonists & inhibitors , Trans-Activators/metabolism , Animals , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Doxycycline/pharmacology , Female , Heterografts , Humans , Mice , Mice, SCID , S-Phase Kinase-Associated Proteins/metabolism , Signal Transduction , Trans-Activators/antagonists & inhibitors , Trans-Activators/genetics , Transcriptional Coactivator with PDZ-Binding Motif Proteins
5.
Nucleic Acids Res ; 45(9): e69, 2017 May 19.
Article in English | MEDLINE | ID: mdl-28108658

ABSTRACT

As with any biological process, cancer development is inherently dynamic. While major efforts continue to catalog the genomic events associated with human cancer, it remains difficult to interpret and extrapolate the accumulating data to provide insights into the dynamic aspects of the disease. Here, we present a computational strategy that enables the construction of a cancer progression model using static tumor sample data. The developed approach overcame many technical limitations of existing methods. Application of the approach to breast cancer data revealed a linear, branching model with two distinct trajectories for malignant progression. The validity of the constructed model was demonstrated in 27 independent breast cancer data sets, and through visualization of the data in the context of disease progression we were able to identify a number of potentially key molecular events in the advance of breast cancer to malignancy.


Subject(s)
Computational Biology , Neoplasms/physiopathology , Breast Neoplasms/genetics , Breast Neoplasms/physiopathology , Disease Progression , Feasibility Studies , Female , Humans , Models, Biological , Mutation , Neoplasms/genetics
6.
Oncotarget ; 5(23): 12166-76, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25361000

ABSTRACT

Triple-negative breast cancer (TNBC) accounts for approximately 15-20% of all breast cancer (BC) cases and contributes disproportionately to BC mortality. TAZ, a key transducer of the Hippo pathway, has recently been demonstrated to confer breast cancer stem cell (CSC) traits. However, TAZ target genes and the underlying transcriptional regulatory pathways responsible for the CSC phenomenon remain unknown. Here, we demonstrate that the oncogenic activity of TAZ is essential for propagation of the malignant phenotype. We further show that constitutively active TAZ tumor-derived cells exhibit unique tumor-initiating properties, including increased self-renewal and metastatic seeding potential, acquired chemotherapy resistance and the ability to efficiently regenerate tumor formation in vivo. Combined digital RNA expression analysis and computational network approaches identify several signaling pathways that distinguish breast cancer tumor-initiating cells (T-ICs) from bulk tumor cells. We demonstrate the utility of this approach by repositioning the small molecule tyrosine kinase inhibitor, Dasatinib, which selectively targets T-ICs and inhibits TNBC growth in vivo.


Subject(s)
Cell Transformation, Neoplastic/genetics , Intracellular Signaling Peptides and Proteins/genetics , Signal Transduction/genetics , Transcriptome/genetics , Triple Negative Breast Neoplasms/genetics , Animals , Blotting, Western , Cell Line, Tumor , Dasatinib , Flow Cytometry , Heterografts , Humans , Mice , Mice, SCID , Neoplastic Stem Cells , Protein Kinase Inhibitors/pharmacology , Pyrimidines/pharmacology , Thiazoles/pharmacology , Trans-Activators , Transcription Factors , Transcriptional Coactivator with PDZ-Binding Motif Proteins , Transduction, Genetic , Transfection
7.
Genome Biol ; 15(8): 440, 2014 Aug 26.
Article in English | MEDLINE | ID: mdl-25155694

ABSTRACT

As molecular profiling data continues to accumulate, the design of integrative computational analyses that can provide insights into the dynamic aspects of cancer progression becomes feasible. Here, we present a novel computational method for the construction of cancer progression models based on the analysis of static tumor samples. We demonstrate the reliability of the method with simulated data, and describe the application to breast cancer data. Our findings support a linear, branching model for breast cancer progression. An interactive model facilitates the identification of key molecular events in the advance of disease to malignancy.


Subject(s)
Breast Neoplasms/pathology , Computational Biology/methods , Models, Biological , Algorithms , Female , Humans , Linear Models
8.
Aging (Albany NY) ; 5(5): 347-56, 2013 May.
Article in English | MEDLINE | ID: mdl-23748164

ABSTRACT

Phosphoinositol-3-kinase (PI3K) pathway is a crucial modulator of many physiological and pathophysiological phenomena, including aging, diabetes and cancer. Protein kinase Akt, a downstream effector of PI3K, controls a plethora of cellular functions, including gene transcription. A key mechanism connecting Akt activity to changes in gene expression is inhibitory phosphorylation of FOXO family of transcription factors. Accordingly, altered expression of FOXO targets may account for many biological consequences of PI3K/Akt signaling. While the previous efforts focused on FOXO-dependent regulation of protein-coding genes, non-coding RNA genes have emerged as equally important targets of many transcription factors. Therefore, we utilized a regulated form of FOXO1 to profile FOXO1-dependent changes in miRNA expression in human cells. Both microarray hybridization and next-generation sequencing revealed changes in the products of a miRNA cluster on X chromosome. Rapid induction of these miRNAs occurred independently of de novo protein synthesis. Furthermore, inhibition of PI3K in cancer cell lines caused derepression of these miRNAs, as would be expected for FOXO-regulated genes. Members of the major oncogenic cascades are significantly overrepresented among the predicted targets of the miRNAs, consistent with tumor-suppressive role of FOXO1. The discovered miRNAs represent new candidate mediators of FOXO1 functions and possible biomarkers of its activity.


Subject(s)
Chromosomes, Human, X/genetics , Forkhead Transcription Factors/metabolism , MicroRNAs/metabolism , Forkhead Box Protein O1 , Forkhead Transcription Factors/genetics , Gene Expression Regulation , HEK293 Cells , Humans , MicroRNAs/genetics , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Transcriptome
9.
Leuk Lymphoma ; 54(2): 387-96, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22812491

ABSTRACT

Understanding the biology of Waldenström macroglobulinemia is hindered by a lack of preclinical models. We report a novel cell line, RPCI-WM1, from a patient treated for WM. The cell line secretes human immunoglobulin M (h-IgM) with κ-light chain restriction identical to the primary tumor. The cell line has a modal chromosomal number of 46 and harbors chromosomal changes such as deletion of 6q21, monoallelic deletion of 9p21 (CDKN2A), 13q14 (RB1) and 18q21 (BCL-2), with a consistent amplification of 14q32 (immunoglobulin heavy chain; IgH) identical to its founding tumor sample. The clonal relationship is confirmed by identical CDR3 length and single nucleotide polymorphisms as well as a matching IgH sequence of the cell line and founding tumor. Both also harbor a heterozygous, non-synonymous mutation at amino acid 265 in the MYD88 gene (L265P). The cell line expresses most of the cell surface markers present on the parent cells. Overall, RPCI-WM1 represents a valuable model to study Waldenström macroglobulinemia.


Subject(s)
Cell Line, Tumor , Waldenstrom Macroglobulinemia/genetics , Waldenstrom Macroglobulinemia/metabolism , Animals , Base Sequence , Cytogenetic Analysis , Disease Models, Animal , Female , Humans , Immunoglobulin Heavy Chains/chemistry , Immunoglobulin Heavy Chains/genetics , Immunoglobulin M/biosynthesis , Immunoglobulin M/genetics , Immunoglobulin kappa-Chains/genetics , Immunoglobulin kappa-Chains/metabolism , Immunophenotyping , Mice , Middle Aged , Molecular Sequence Data , Mutation , Myeloid Differentiation Factor 88/genetics , Polymorphism, Single Nucleotide , Sequence Alignment , Transplantation, Heterologous , Waldenstrom Macroglobulinemia/pathology
10.
Genes Chromosomes Cancer ; 51(12): 1067-78, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22887771

ABSTRACT

Only a minority of intraductal carcinomas of the breast give rise to stromally invasive disease. We microdissected 206 paraffin blocks representing 116 different cases of low-grade ductal carcinoma in situ (DCIS). Fifty-five were pure DCIS (PD) cases without progression to invasive carcinoma. Sixty-one cases had a small invasive component. DNA was extracted from microdissected sections and hybridized to high-density bacterial artificial chromosome arrays. Array comparative genomic hybridization analysis of 118 hybridized DNA samples yielded data on 69 samples that were suitable for further statistical analysis. This cohort included 20 pure DCIS cases, 25 mixed DCIS (MD), and 24 mixed invasive carcinoma samples. PD cases had a higher frequency of DNA copy number changes than MD cases, and the latter had similar DNA profiles compared to paired invasive carcinomas. Copy number changes on 13 chromosomal arms occurred at different rates in PD versus MD lesions. Eight of 19 candidate genes residing at those loci were confirmed to have differential copy number changes by quantitative PCR. NCOR2/SMRT and NR4A1 (both on 12q), DYNLRB2 (16q), CELSR1, UPK3A, and ST13 (all on 22q) were more frequently amplified in PD. Moreover, NCOR2, NR4A1, and DYNLRB2 showed more frequent copy number losses in MD. GRAP2 (22q) was more often amplified in MD, whereas TAF1C (16q) was more commonly deleted in PD. A multigene model comprising these candidate genes discriminated between PD and MD lesions with high accuracy. These findings suggest that the propensity to invade the stroma may be encoded in the genome of intraductal carcinomas.


Subject(s)
Breast Neoplasms/genetics , Breast/pathology , Carcinoma, Ductal, Breast/genetics , Carcinoma, Intraductal, Noninfiltrating/genetics , DNA Copy Number Variations , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Comparative Genomic Hybridization , Disease Progression , Female , Humans
11.
PLoS One ; 6(10): e25940, 2011.
Article in English | MEDLINE | ID: mdl-22022476

ABSTRACT

BACKGROUND: Bone mineral density (BMD) loss commonly occurs after hematopoietic cell transplantation (HCT). Hypothesizing that genetic variants may influence post-HCT BMD loss, we conducted a prospective study to examine the associations of single nucleotide polymorphisms (SNP) in bone metabolism pathways and acute BMD loss after HCT. METHODS AND FINDINGS: We genotyped 122 SNPs in 45 genes in bone metabolism pathways among 121 autologous and allogeneic HCT patients. BMD changes from pre-HCT to day +100 post-HCT were analyzed in relation to these SNPs in linear regression models. After controlling for clinical risk factors, we identified 16 SNPs associated with spinal or femoral BMD loss following HCT, three of which have been previously implicated in genome-wide association studies of bone phenotypes, including rs2075555 in COL1A1, rs9594738 in RANKL, and rs4870044 in ESR1. When multiple SNPs were considered simultaneously, they explained 5-35% of the variance in post-HCT BMD loss. There was a significant trend between the number of risk alleles and the magnitude of BMD loss, with patients carrying the most risk alleles having the greatest loss. CONCLUSION: Our data provide the first evidence that common genetic variants play an important role in BMD loss among HCT patients similar to age-related BMD loss in the general population. This infers that the mechanism for post-HCT bone loss is a normal aging process that is accelerated during HCT. A limitation of our study comes from its small patient population; hence future larger studies are warranted to validate our findings.


Subject(s)
Bone Density/genetics , Genetic Variation , Hematopoietic Stem Cell Transplantation/adverse effects , Polymorphism, Single Nucleotide/genetics , Adult , Aged , Alleles , DNA/genetics , Female , Genome, Human/genetics , Genotype , Humans , Male , Middle Aged , Models, Genetic , Risk Factors
12.
PLoS One ; 6(9): e24363, 2011.
Article in English | MEDLINE | ID: mdl-21931690

ABSTRACT

Recent studies revealed that hemoglobin is expressed in some non-erythrocytes and it suppresses oxidative stress when overexpressed. Oxidative stress plays a critical role in the pathogenesis of non-alcoholic steatohepatitis (NASH). This study was designed to investigate whether hemoglobin is expressed in hepatocytes and how it is related to oxidative stress in NASH patients. Analysis of microarray gene expression data revealed a significant increase in the expression of hemoglobin alpha (HBA1) and beta (HBB) in liver biopsies from NASH patients. Increased hemoglobin expression in NASH was validated by quantitative real time PCR. However, the expression of hematopoietic transcriptional factors and erythrocyte specific marker genes were not increased, indicating that increased hemoglobin expression in NASH was not from erythropoiesis, but could result from increased expression in hepatocytes. Immunofluorescence staining demonstrated positive HBA1 and HBB expression in the hepatocytes of NASH livers. Hemoglobin expression was also observed in human hepatocellular carcinoma HepG2 cell line. Furthermore, treatment with hydrogen peroxide, a known oxidative stress inducer, increased HBA1 and HBB expression in HepG2 and HEK293 cells. Importantly, hemoglobin overexpression suppressed oxidative stress in HepG2 cells. We concluded that hemoglobin is expressed by hepatocytes and oxidative stress upregulates its expression. Suppression of oxidative stress by hemoglobin could be a mechanism to protect hepatocytes from oxidative damage in NASH.


Subject(s)
Fatty Liver/genetics , Glycated Hemoglobin/genetics , Hemoglobins/genetics , Hepatocytes/metabolism , Oxidative Stress/genetics , Up-Regulation/genetics , alpha-Globins/genetics , beta-Globins/genetics , Adolescent , Biopsy , Case-Control Studies , Child , Child, Preschool , Fatty Liver/pathology , Female , Glycated Hemoglobin/metabolism , HEK293 Cells , Hemoglobins/metabolism , Hep G2 Cells , Hepatocytes/pathology , Humans , Liver/metabolism , Liver/pathology , Male , Non-alcoholic Fatty Liver Disease , Young Adult , alpha-Globins/metabolism , beta-Globins/metabolism
13.
Cancer ; 117(21): 4861-8, 2011 Nov 01.
Article in English | MEDLINE | ID: mdl-21456022

ABSTRACT

BACKGROUND: Constitutive activation of signal transducer and activator of transcription-3 (STAT3) was detected in blasts from approximately 50% of patients with acute myeloid leukemia (AML) and was correlated with an adverse outcome. In vitro treatment of AML blasts with arsenic trioxide (ATO) down-regulated STAT3 activity within 6 hours associated with a reduced viability within 48 hours. METHODS: A phase 1 clinical trial to evaluate the biologically effective dose and/or the maximally tolerated dose (MTD) of ATO in vivo in conjunction with high-dose cytarabine (Hidac) and idarubicin (Ida) in patients with AML aged <60 years was conducted. Data were compared with 117 historic AML patients who had received treatment with Hidac/Ida. RESULTS: In total, 61 patients were enrolled onto 11 different dose levels (from 0.01 to 0.65 mg/kg ideal body weight). The MTD was 0.5 mg/kg. Compared with historic controls, patients who received ATO/Hidac/Ida, although they had similar pretreatment characteristics, had better overall survival (P = .039). CONCLUSIONS: ATO priming may have improved the outcome of patients aged <60 years with AML who received Hidac/Ida. The current data suggested that ATO may enhance the effect of chemotherapy. The authors concluded that further studies of this novel combination are warranted.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Arsenicals/administration & dosage , Cytarabine/administration & dosage , Idarubicin/administration & dosage , Leukemia, Myeloid, Acute/drug therapy , Oxides/administration & dosage , STAT3 Transcription Factor/metabolism , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Arsenic Trioxide , Arsenicals/adverse effects , Cytarabine/adverse effects , Down-Regulation , Female , Humans , Idarubicin/adverse effects , Male , Middle Aged , Oxides/adverse effects
14.
Cancer Invest ; 29(4): 300-7, 2011 May.
Article in English | MEDLINE | ID: mdl-21469979

ABSTRACT

We screened the whole tumor genome to identify DNA copy number gains and losses that discriminate between primary breast carcinomas (MP) and their nodal metastases (ML). Six candidate genes were confirmed by quantitative PCR to have differentially distributed copy number changes. Three of the genes (ERRγ, DDX6, and TIAM1) were more commonly amplified in nodal metastases. Principal component analysis revealed that MP-ML pairs varied markedly in their genomic divergence. The latter was larger in PR-negative tumors. Nodal metastases may form early or late in the development of breast carcinomas and PR-negative tumors may metastasize earlier or are genomically less stable.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/secondary , DNA Copy Number Variations , Gene Expression Regulation, Neoplastic , Comparative Genomic Hybridization , Female , Gene Expression Profiling/methods , Genetic Association Studies , Humans , Lymphatic Metastasis , Polymerase Chain Reaction , Principal Component Analysis
15.
Clin Cancer Res ; 17(10): 3443-54, 2011 May 15.
Article in English | MEDLINE | ID: mdl-21385932

ABSTRACT

PURPOSE: To determine the recurring DNA copy number alterations (CNA) in classical Hodgkin lymphoma (HL) by microarray-based comparative genomic hybridization (aCGH) using laser capture microdissected CD30(+) Hodgkin and Reed-Sternberg (HRS) cells. EXPERIMENTAL DESIGN: Archived tissues from 27 CD30(+) HL plus control samples were analyzed by DNA microarrays. The HL molecular karyotypes were compared with the genomic profiles of germinal center B cells and treatment outcome (chemotherapy responsive vs. primary refractory disease). RESULTS: Gains and losses observed in more than 35% of HL samples were localized to 22 and 12 chromosomal regions, respectively. Frequent gains (>65%) were associated with growth and proliferation, NF-κB activation, cell-cycle control, apoptosis, and immune and lymphoid development. Frequent losses (>40%) observed encompassed tumor suppressor genes (SPRY1, NELL1, and ID4, inhibitor of DNA binding 4), transcriptional repressors (TXNIP, thioredoxin interacting protein), SKP2 (S-phase kinase-associated protein 2; ubiquitin ligase component), and an antagonist of NF-κB activation (PPARGC1A). In comparison to the germinal center profiles, the most frequent imbalances in HL were losses in 5p13 (AMACR, GDNF, and SKP2), and gains in 7q36 (SHH, sonic hedgehog homolog) and 9q34 (ABL1, CDK9, LCN2, and PTGES). Gains (>35%) in the HL chemoresponsive patients housed genes known to regulate T-cell trafficking or NF-κB activation (CCL22, CX3CL1, CCL17, DOK4, and IL10), whereas the refractory samples showed frequent loss of 4q27 (interleukin; IL21/IL2) and 17p12, and gain of 19q13.3 (BCL3/RELB). CONCLUSION: We identified nonrandom CNAs in the molecular karyotypes of classical HL. Several recurring genetic lesions correlated with disease outcome. These findings may be useful prognostic markers in the counseling and management of patients and for the development of novel therapeutic approaches in primary refractory HL.


Subject(s)
DNA Copy Number Variations , Drug Resistance, Neoplasm/genetics , Hodgkin Disease/genetics , Hodgkin Disease/pathology , Reed-Sternberg Cells/pathology , Adolescent , Adult , Child , Child, Preschool , Cohort Studies , Comparative Genomic Hybridization , Early Detection of Cancer , Female , Gene Expression Regulation, Neoplastic , Hodgkin Disease/metabolism , Humans , Karyotyping/methods , Male , Middle Aged , Reed-Sternberg Cells/drug effects , Reed-Sternberg Cells/metabolism , Young Adult
16.
Hum Genet ; 130(5): 623-32, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21442329

ABSTRACT

Human trisomy 21, the chromosomal basis of Down syndrome (DS), is the most common genetic cause of heart defects. Regions on human chromosome 21 (Hsa21) are syntenically conserved with three regions located on mouse chromosome 10 (Mmu10), Mmu16 and Mmu17. In this study, we have analyzed the impact of duplications of each syntenic region on cardiovascular development in mice and have found that only the duplication on Mmu16, i.e., Dp(16)1Yey, is associated with heart defects. Furthermore, we generated two novel mouse models carrying a 5.43-Mb duplication and a reciprocal deletion between Tiam1 and Kcnj6 using chromosome engineering, Dp(16Tiam1-Kcnj6)Yey/+ and Df(16Tiam1-Kcnj6)Yey/+, respectively, within the 22.9-Mb syntenic region on Mmu16. We found that Dp(16Tiam1-Kcnj6)Yey/+, but not Dp(16)1Yey/Df(16Tiam1-Kcnj6)Yey, resulted in heart defects, indicating that triplication of the Tiam1-Knj6 region is necessary and sufficient to cause DS-associated heart defects. Our transcriptional analysis of Dp(16Tiam1-Kcnj6)Yey/+ embryos confirmed elevated expression levels for the genes located in the Tiam-Kcnj6 region. Therefore, we established the smallest critical genomic region for DS-associated heart defects to lay the foundation for identifying the causative gene(s) for this phenotype.


Subject(s)
Down Syndrome/genetics , Heart Defects, Congenital/genetics , Animals , Disease Models, Animal , Female , G Protein-Coupled Inwardly-Rectifying Potassium Channels/genetics , Gene Duplication/genetics , Guanine Nucleotide Exchange Factors/genetics , Male , Mice , Mice, Mutant Strains , Sequence Deletion/genetics , Synteny/genetics , T-Lymphoma Invasion and Metastasis-inducing Protein 1
17.
Metabolism ; 60(7): 1001-11, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21075404

ABSTRACT

Fatty liver is a prerequisite for the development of nonalcoholic steatohepatitis (NASH). The homeostasis of hepatic lipid is determined by the dynamic balance of multiple pathways introducing lipids into or removing lipids from hepatocytes. We aim to study the different contributions of major lipid pathways to fat deposition in NASH livers. Expression of the lipid metabolism-related genes was analyzed by microarray and quantitative real-time polymerase chain reaction analysis. The expression levels of genes responsible for the rate-limiting steps of fatty acid uptake (CD36, FABPpm, SLC27A2, and SLC27A5), de novo synthesis (ACACB), oxidation (CPT-1), and very low-density lipoprotein (VLDL) secretion (ApoB) were used to evaluate the relative activity of each pathway. The expression levels for CD36 and CPT-1 were confirmed by Western blot analysis. Fatty acid uptake pathways were up-regulated to a higher degree than other pathways. The de novo synthesis pathway was also up-regulated more than both VLDL secretion and fatty acid oxidation pathways. In contrast to other NASH livers, one NASH liver exhibited lower ApoB and CPT-1 expression levels than normal controls. The increased fatty acid uptake and de novo synthesis were the most common causes for steatosis in NASH patients. In a rare case, impaired VLDL secretion and fatty acid oxidation contributed to the development of steatosis. Our study promises a simple method for the determination of why hepatic steatosis occurs in individual patients. This method may allow specific targeting of therapeutic treatments in individual patients.


Subject(s)
Lipid Metabolism/genetics , Liver/metabolism , Adolescent , CD36 Antigens/biosynthesis , CD36 Antigens/genetics , Carnitine O-Palmitoyltransferase/biosynthesis , Carnitine O-Palmitoyltransferase/genetics , Child , Child, Preschool , Fatty Liver/genetics , Fatty Liver/metabolism , Female , Gene Expression Profiling , Humans , Infant , Lipids/analysis , Lipoproteins, VLDL/genetics , Lipoproteins, VLDL/metabolism , Liver/chemistry , Male , Non-alcoholic Fatty Liver Disease , Up-Regulation , Young Adult
18.
J Cancer Res Clin Oncol ; 137(5): 795-809, 2011 May.
Article in English | MEDLINE | ID: mdl-20680643

ABSTRACT

PURPOSE: We employed a whole genome tumor profiling approach in an attempt to identify DNA copy number alterations (CNAs) and new candidate genes that are correlated with the metastatic potential of a primary breast carcinoma and with progression at the metastatic site. METHODS: Fifty-four small (≤ 2 cm), high grade, ER-positive, formalin-fixed invasive ductal carcinomas were suitable for whole genome profiling analysis. Twenty-four of them did not form metastases within 5-10 years (unmatched primaries, UP). Thirty tumors had at least one synchronous axillary lymph node metastasis (matched primaries, MP; matched lymph node metastases, ML). Genomic DNA was hybridized to high density (19k) BAC arrays. Statistical analysis revealed differential distributions of CNAs between UP and MP and between MP and ML, respectively. We selected 27 candidate genes for validation experiments using quantitative (Q-)PCR of genomic DNA. For tetraspanin TSPAN1, we studied mRNA expression levels in a separate cohort of primary breast carcinomas and in breast cell lines. RESULTS: Matched primary (MP) tumors had a threefold higher rate of DNA copy number losses compared to UP tumors. In the UP-MP comparison, 186 BACs were differentially amplified or deleted. Most of them were localized to chromosomes 7p, 16q and 18q. In the MP-ML comparison, 131 BACs showed differential CNAs. Most of them were localized to chromosomes 1q and 20. By Q-PCR, seven candidate genes could be confirmed to show differential distributions of CNAs. TSPAN1 was amplified in UP and deleted in MP tumors. The gene was markedly downregulated in ER-negative and high-grade breast cancers. CONCLUSIONS: Metastasizing tumors had a higher rate of deletions, suggesting possible inactivation of metastasis suppressor genes. We provide preliminary evidence that TSPAN1 may be another important breast cancer suppressor gene belonging to the tetraspanin superfamily.


Subject(s)
Breast Neoplasms/genetics , Breast Neoplasms/pathology , Gene Dosage , Membrane Proteins/genetics , Cell Line, Tumor , Chromosomes, Artificial, Bacterial , Comparative Genomic Hybridization , Female , Genes, Tumor Suppressor , Humans , Lymphatic Metastasis , Polymerase Chain Reaction , RNA, Messenger/analysis , Tetraspanins
19.
Cancer Genet Cytogenet ; 202(2): 101-7, 2010 Oct 15.
Article in English | MEDLINE | ID: mdl-20875872

ABSTRACT

Normal karyotype (NK) is the most common cytogenetic group in acute myeloid leukemia (AML) diagnosis; however, up to 50% of these patients at relapse will have aberrant karyotype (AK) AML. To determine the etiology of relapsed AK AML cells, we evaluated cytogenetic, immunophenotypic, and molecular results of 17 patients with diagnostic NK AML and relapsed AK AML at our institute. AK AML karyotype was diverse, involving no favorable and largely (8 of 17) complex cytogenetics. Despite clear cytogenetic differences, immunophenotype and NPM1/FLT3 gene mutation status did not change between presentation and relapse in 83% (10 of 12) and 94% (15 of 16) cases, respectively. High-resolution array-based comparative genomic hybridization (aCGH) performed via paired aCGH on NK AML and AK AML samples from the same patient confirmed cytogenetic aberrations only in the relapse sample. Analysis of 16 additional diagnostic NK AML samples revealed no evidence of submicroscopic aberrations undetected by conventional cytogenetics in any case. These results favor evolution of NK AML leukemia cells with acquisition of novel genetic changes as the most common etiology of AK AML relapse as opposed to secondary leukemogenesis. Additional studies are needed to confirm whether AK AML cells represent selection of rare preexisting clones below aCGH detection and to further characterize the molecular lesions found at time of AK AML relapse.


Subject(s)
Genomics , Immunophenotyping , Leukemia, Myeloid, Acute/enzymology , Leukemia, Myeloid, Acute/genetics , Nuclear Proteins/genetics , fms-Like Tyrosine Kinase 3/genetics , Adult , Aged , Aged, 80 and over , Chromosome Aberrations , Comparative Genomic Hybridization , DNA Mutational Analysis , Female , Humans , Karyotyping , Male , Middle Aged , Nucleophosmin , Recurrence , Treatment Outcome , Young Adult
20.
Genes Chromosomes Cancer ; 49(9): 791-802, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20607851

ABSTRACT

The goal of this study was to identify recurrent regions of genomic gain or loss in endometrial cancer of the endometrioid type in the context of racial disparities in mortality for this disease. Array comparative genomic hybridization (aCGH) analysis was performed on 80 frozen primary tumors from the Gynecologic Oncology Group (GOG)-210 bank using the RPCI 19K BAC arrays. The 80 patients included 20 African American (AA) Stage I, 20 White (W) Stage I, 20 African American (AA) Stage IIIC/IV, and 20 White (W) Stage IIIC/IV. A separate subset of 220 endometrial cancers with outcome data was used for validation. A 1.6-Mbp region of gain at 1q23 was identified by aCGH in all AA patients and high grade W patients, but not W low grade patients. In the validation arm of 220 patients copy number gain at this region was validated using FISH and locus specific BACs. The number of AA patients in the validation arm was too small to confirm the aCGH association with racial disparity. Kaplan-Meier curves for survival showed a significant difference for gain at 1q23 versus no gain (log rank P = 0.0014). When subdivided into various groups of risk by stage and grade the survival curves showed a decreased survival for high grade and/or stage tumors, but not for low grade and/or stage endometrioid tumors. Univariate analyses for gain at 1q23 showed a significant association (P = 0.009) with survival. Multivariate analysis for gain at 1q23 did not show a significant association with survival (P = 0.14).


Subject(s)
Black or African American/genetics , Comparative Genomic Hybridization , Endometrial Neoplasms/ethnology , Endometrial Neoplasms/genetics , White People/genetics , Adenocarcinoma, Clear Cell/ethnology , Adenocarcinoma, Clear Cell/genetics , Adenocarcinoma, Clear Cell/therapy , Carcinoma, Endometrioid/ethnology , Carcinoma, Endometrioid/genetics , Carcinoma, Endometrioid/therapy , Chromosomes, Human, Pair 1/genetics , Cystadenocarcinoma, Serous/ethnology , Cystadenocarcinoma, Serous/genetics , Cystadenocarcinoma, Serous/therapy , Endometrial Neoplasms/therapy , Female , Gene Amplification , Humans , In Situ Hybridization, Fluorescence , Middle Aged , Survival Rate , Treatment Outcome
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