80 research outputs found
Hierarchies among Genuine Multipartite Entangling Capabilities of Quantum Gates
We categorize quantum gates according to their capability to generate genuine
multipartite entanglement based on the hierarchy of multipartite separable
states. In particular, when a fixed unitary operator acts on the set of
k-separable states, the maximal (average) genuine multipartite entanglement
(GME) content produced via that particular unitary operator is determined after
maximizing over the set of k-separable input states. We identify unitary
operators that are beneficial for generating high GME when the input states are
entangled in some bipartition, although the picture can also be reversed in
which entanglement in inputs does not help. We characterize maximum entangling
power of a variety of unitary operators including special classes of quantum
gates, diagonal, permutation and Haar uniformly generated unitary operators by
computing generalized geometric measure (GGM) as GME quantifier. We determine
the unitary operators and their corresponding inputs which can create the
resulting states having maximum GGM.Comment: v1: 8 pages, 8 figures; v2: 11 pages, 6 figures, new sections
including new results adde
Recommended from our members
Epigenomic Diversity of Colorectal Cancer Indicated by LINE-1 Methylation in a Database of 869 Tumors
Background: Genome-wide DNA hypomethylation plays a role in genomic instability and carcinogenesis. LINE-1 (L1 retrotransposon) constitutes a substantial portion of the human genome, and LINE-1 methylation correlates with global DNA methylation status. LINE-1 hypomethylation in colon cancer has been strongly associated with poor prognosis. However, whether LINE-1 hypomethylators constitute a distinct cancer subtype remains uncertain. Recent evidence for concordant LINE-1 hypomethylation within synchronous colorectal cancer pairs suggests the presence of a non-stochastic mechanism influencing tumor LINE-1 methylation level. Thus, it is of particular interest to examine whether its wide variation can be attributed to clinical, pathologic or molecular features.Design Utilizing a database of 869 colorectal cancers in two prospective cohort studies, we constructed multivariate linear and logistic regression models for LINE-1 methylation (quantified by Pyrosequencing). Variables included age, sex, body mass index, family history of colorectal cancer, smoking status, tumor location, stage, grade, mucinous component, signet ring cells, tumor infiltrating lymphocytes, CpG island methylator phenotype (CIMP), microsatellite instability, expression of TP53 (p53), CDKN1A (p21), CTNNB1 (β-catenin), PTGS2 (cyclooxygenase-2), and FASN, and mutations in KRAS, BRAF, and PIK3CA. Results: Tumoral LINE-1 methylation ranged from 23.1 to 90.3 of 0-100 scale (mean 61.4; median 62.3; standard deviation 9.6), and distributed approximately normally except for extreme hypomethylators [LINE-1 methylation < 40; N = 22 (2.5%), which were far more than what could be expected by normal distribution]. LINE-1 extreme hypomethylators were significantly associated with younger patients (p = 0.0058). Residual plot by multivariate linear regression showed that LINE-1 extreme hypomethylators clustered as one distinct group, separate from the main tumor group. The multivariate linear regression model could explain 8.4% of the total variability of LINE-1 methylation (R-square = 0.084). Multivariate logistic regression models for binary LINE-1 hypomethylation outcomes (cutoffs of 40, 50 and 60) showed at most fair predictive ability (area under receiver operator characteristics curve < 0.63). Conclusions: LINE-1 extreme hypomethylators appear to constitute a previously-unrecognized, distinct subtype of colorectal cancers, which needs to be confirmed by additional studies. Our tumor LINE-1 methylation data indicate enormous epigenomic diversity of individual colorectal cancers
Recommended from our members
Joint Effects of Colorectal Cancer Susceptibility Loci, Circulating 25-Hydroxyvitamin D and Risk of Colorectal Cancer
Background: Genome wide association studies (GWAS) have identified several SNPs associated with colorectal cancer (CRC) susceptibility. Vitamin D is also inversely associated with CRC risk. Methods: We examined main and joint effects of previously GWAS identified genetic markers of CRC and plasma 25-hydroxyvitamin D (25(OH)D) on CRC risk in three prospective cohorts: the Nurses' Health Study (NHS), the Health Professionals Follow-up Study (HPFS), and the Physicians' Health Study (PHS). We included 1895 CRC cases and 2806 controls with genomic DNA. We calculated odds ratios and 95% confidence intervals for CRC associated with additive genetic risk scores (GRSs) comprised of all CRC SNPs and subsets of these SNPs based on proximity to regions of increased vitamin D receptor binding to vitamin D response elements (VDREs), based on published ChiP-seq data. Among a subset of subjects with additional prediagnostic 25(OH)D we tested multiplicative interactions between plasma 25(OH)D and GRS's. We used fixed effects models to meta-analyze the three cohorts. Results: The per allele multivariate OR was 1.12 (95% CI, 1.06–1.19) for GRS-proximalVDRE; and 1.10 (95% CI, 1.06–1.14) for GRS-nonproxVDRE. The lowest quartile of plasma 25(OH)D compared with the highest, had a multivariate OR of 0.63 (95% CI, 0.48–0.82) for CRC. We did not observe any significant interactions between any GRSs and plasma 25(OH)D. Conclusions: We did not observe evidence for the modification of genetic susceptibility for CRC according to vitamin D status, or evidence that the effect of common CRC risk alleles differed according to their proximity to putative VDR binding sites
Epigenomic diversity of colorectal cancer indicated by LINE-1 methylation in a database of 869 tumors
<p>Abstract</p> <p>Background</p> <p>Genome-wide DNA hypomethylation plays a role in genomic instability and carcinogenesis. LINE-1 (L1 retrotransposon) constitutes a substantial portion of the human genome, and LINE-1 methylation correlates with global DNA methylation status. LINE-1 hypomethylation in colon cancer has been strongly associated with poor prognosis. However, whether LINE-1 hypomethylators constitute a distinct cancer subtype remains uncertain. Recent evidence for concordant LINE-1 hypomethylation within synchronous colorectal cancer pairs suggests the presence of a non-stochastic mechanism influencing tumor LINE-1 methylation level. Thus, it is of particular interest to examine whether its wide variation can be attributed to clinical, pathologic or molecular features.</p> <p>Design</p> <p>Utilizing a database of 869 colorectal cancers in two prospective cohort studies, we constructed multivariate linear and logistic regression models for LINE-1 methylation (quantified by Pyrosequencing). Variables included age, sex, body mass index, family history of colorectal cancer, smoking status, tumor location, stage, grade, mucinous component, signet ring cells, tumor infiltrating lymphocytes, CpG island methylator phenotype (CIMP), microsatellite instability, expression of TP53 (p53), CDKN1A (p21), CTNNB1 (β-catenin), PTGS2 (cyclooxygenase-2), and FASN, and mutations in <it>KRAS, BRAF</it>, and <it>PIK3CA</it>.</p> <p>Results</p> <p>Tumoral LINE-1 methylation ranged from 23.1 to 90.3 of 0-100 scale (mean 61.4; median 62.3; standard deviation 9.6), and distributed approximately normally except for extreme hypomethylators [LINE-1 methylation < 40; N = 22 (2.5%), which were far more than what could be expected by normal distribution]. LINE-1 extreme hypomethylators were significantly associated with younger patients (p = 0.0058). Residual plot by multivariate linear regression showed that LINE-1 extreme hypomethylators clustered as one distinct group, separate from the main tumor group. The multivariate linear regression model could explain 8.4% of the total variability of LINE-1 methylation (R-square = 0.084). Multivariate logistic regression models for binary LINE-1 hypomethylation outcomes (cutoffs of 40, 50 and 60) showed at most fair predictive ability (area under receiver operator characteristics curve < 0.63).</p> <p>Conclusions</p> <p>LINE-1 extreme hypomethylators appear to constitute a previously-unrecognized, distinct subtype of colorectal cancers, which needs to be confirmed by additional studies. Our tumor LINE-1 methylation data indicate enormous epigenomic diversity of individual colorectal cancers.</p
Genome-wide association study identifies common variants associated with circulating vitamin E levels
In genome-wide association studies (GWAS) of common genetic variants associated with circulating alpha- and gamma-tocopherol concentrations in two adult cohorts comprising 5006 men of European descent, we observed three loci associated with alpha-tocopherol levels, two novel single-nucleotide polymorphisms (SNPs), rs2108622 on 19pter-p13.11 (P= 1.7 × 10−8) and rs11057830 on 12q24.31 (P= 2.0 × 10−8) and confirmed a previously reported locus marked by rs964184 on 11q23.3 (P= 2.7 × 10−10). The three SNPs have been reported to be associated with lipid metabolism and/or regulation. We replicated these findings in a combined meta-analysis with two independent samples, P= 7.8 × 10−12 (rs964184 on 11q23.3 near BUD13, ZNF259 and APOA1/C3/A4/A5), P= 1.4 × 10−10 (rs2108622 on 19pter-p13.11 near CYP4F2) and P= 8.2 × 10−9 (rs11057830 on 12q24.31 near SCARB1). Combined, these SNPs explain 1.7% of the residual variance in log alpha-tocopherol levels. In one of the two male GWAS cohorts (n= 992), no SNPs were significantly associated with gamma-tocopherol concentrations after including data from the replication sample for 71 independent SNPs with P< 1 × 10−4 identified
Alcohol consumption and breast tumor gene expression
Background Alcohol consumption is an established risk factor for breast cancer and the association generally appears stronger among estrogen receptor (ER)-positive tumors. However, the biological mechanisms underlying this association are not completely understood. Methods We analyzed messenger RNA (mRNA) microarray data from both invasive breast tumors (N = 602) and tumor-adjacent normal tissues (N = 508) from participants diagnosed with breast cancer in the Nurses’ Health Study (NHS) and NHSII. Multivariable linear regression, controlling for other known breast cancer risk factors, was used to identify differentially expressed genes by pre-diagnostic alcohol intake. For pathway analysis, we performed gene set enrichment analysis (GSEA). Differentially expressed genes or enriched pathway-defined gene sets with false discovery rate (FDR) \u3c0.1 identified in tumors were validated in RNA sequencing data of invasive breast tumors (N = 166) from The Cancer Genome Atlas. Results No individual genes were significantly differentially expressed by alcohol consumption in the NHS/NHSII. However, GSEA identified 33 and 68 pathway-defined gene sets at FDR \u3c0.1 among 471 ER+ and 127 ER- tumors, respectively, all of which were validated. Among ER+ tumors, consuming 10+ grams of alcohol per day (vs. 0) was associated with upregulation in RNA metabolism and transport, cell cycle regulation, and DNA repair, and downregulation in lipid metabolism. Among ER- tumors, in addition to upregulation in RNA processing and cell cycle, alcohol intake was linked to overexpression of genes involved in cytokine signaling, including interferon and transforming growth factor (TGF)-β signaling pathways, and translation and post-translational modifications. Lower lipid metabolism was observed in both ER+ tumors and ER+ tumor-adjacent normal samples. Most of the significantly enriched gene sets identified in ER- tumors showed a similar enrichment pattern among ER- tumor-adjacent normal tissues. Conclusions Our data suggest that moderate alcohol consumption (i.e. 10+ grams/day, equivalent to one or more drinks/day) is associated with several specific and reproducible biological processes and pathways, which adds potential new insight into alcohol-related breast carcinogenesis
Comprehensive Biostatistical Analysis of CpG Island Methylator Phenotype in Colorectal Cancer Using a Large Population-Based Sample
The CpG island methylator phenotype (CIMP) is a distinct phenotype associated with microsatellite instability (MSI) and BRAF mutation in colon cancer. Recent investigations have selected 5 promoters (CACNA1G, IGF2, NEUROG1, RUNX3 and SOCS1) as surrogate markers for CIMP-high. However, no study has comprehensively evaluated an expanded set of methylation markers (including these 5 markers) using a large number of tumors, or deciphered the complex clinical and molecular associations with CIMP-high determined by the validated marker panel. METHOLODOLOGY/PRINCIPAL FINDINGS: DNA methylation at 16 CpG islands [the above 5 plus CDKN2A (p16), CHFR, CRABP1, HIC1, IGFBP3, MGMT, MINT1, MINT31, MLH1, p14 (CDKN2A/ARF) and WRN] was quantified in 904 colorectal cancers by real-time PCR (MethyLight). In unsupervised hierarchical clustering analysis, the 5 markers (CACNA1G, IGF2, NEUROG1, RUNX3 and SOCS1), CDKN2A, CRABP1, MINT31, MLH1, p14 and WRN were generally clustered with each other and with MSI and BRAF mutation. KRAS mutation was not clustered with any methylation marker, suggesting its association with a random methylation pattern in CIMP-low tumors. Utilizing the validated CIMP marker panel (including the 5 markers), multivariate logistic regression demonstrated that CIMP-high was independently associated with older age, proximal location, poor differentiation, MSI-high, BRAF mutation, and inversely with LINE-1 hypomethylation and beta-catenin (CTNNB1) activation. Mucinous feature, signet ring cells, and p53-negativity were associated with CIMP-high in only univariate analysis. In stratified analyses, the relations of CIMP-high with poor differentiation, KRAS mutation and LINE-1 hypomethylation significantly differed according to MSI status.Our study provides valuable data for standardization of the use of CIMP-high-specific methylation markers. CIMP-high is independently associated with clinical and key molecular features in colorectal cancer. Our data also suggest that KRAS mutation is related with a random CpG island methylation pattern which may lead to CIMP-low tumors
Novel Associations between Common Breast Cancer Susceptibility Variants and Risk-Predicting Mammographic Density Measures.
Mammographic density measures adjusted for age and body mass index (BMI) are heritable predictors of breast cancer risk, but few mammographic density-associated genetic variants have been identified. Using data for 10,727 women from two international consortia, we estimated associations between 77 common breast cancer susceptibility variants and absolute dense area, percent dense area and absolute nondense area adjusted for study, age, and BMI using mixed linear modeling. We found strong support for established associations between rs10995190 (in the region of ZNF365), rs2046210 (ESR1), and rs3817198 (LSP1) and adjusted absolute and percent dense areas (all P < 10(-5)). Of 41 recently discovered breast cancer susceptibility variants, associations were found between rs1432679 (EBF1), rs17817449 (MIR1972-2: FTO), rs12710696 (2p24.1), and rs3757318 (ESR1) and adjusted absolute and percent dense areas, respectively. There were associations between rs6001930 (MKL1) and both adjusted absolute dense and nondense areas, and between rs17356907 (NTN4) and adjusted absolute nondense area. Trends in all but two associations were consistent with those for breast cancer risk. Results suggested that 18% of breast cancer susceptibility variants were associated with at least one mammographic density measure. Genetic variants at multiple loci were associated with both breast cancer risk and the mammographic density measures. Further understanding of the underlying mechanisms at these loci could help identify etiologic pathways implicated in how mammographic density predicts breast cancer risk.ABCFS: The Australian Breast Cancer Family Registry (ABCFR; 1992-1995) was supported by
the Australian NHMRC, the New South Wales Cancer Council, and the Victorian Health
Promotion Foundation (Australia), and by grant UM1CA164920 from the USA National
Cancer Institute. The Genetic Epidemiology Laboratory at the University of Melbourne has
also received generous support from Mr B. Hovey and Dr and Mrs R.W. Brown to whom we
are most grateful. The content of this manuscript does not necessarily reflect the views or
policies of the National Cancer Institute or any of the collaborating centers in the Breast
Breast Cancer Susceptibility Variants and Mammographic Density
5
Cancer Family Registry (BCFR), nor does mention of trade names, commercial products, or
organizations imply endorsement by the USA Government or the BCFR.
BBCC: This study was funded in part by the ELAN-Program of the University Hospital
Erlangen; Katharina Heusinger was funded by the ELAN program of the University Hospital
Erlangen. BBCC was supported in part by the ELAN program of the Medical Faculty,
University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg.
EPIC-Norfolk: This study was funded by research programme grant funding from Cancer
Research UK and the Medical Research Council with additional support from the Stroke
Association, British Heart Foundation, Department of Health, Research into Ageing and
Academy of Medical Sciences.
MCBCS: This study was supported by Public Health Service Grants P50 CA 116201, R01 CA
128931, R01 CA 128931-S01, R01 CA 122340, CCSG P30 CA15083, from the National Cancer
Institute, National Institutes of Health, and Department of Health and Human Services.
MCCS: Melissa C. Southey is a National Health and Medical Research Council Senior
Research Fellow and a Victorian Breast Cancer Research Consortium Group Leader. The
study was supported by the Cancer Council of Victoria and by the Victorian Breast Cancer
Research Consortium.
MEC: National Cancer Institute: R37CA054281, R01CA063464, R01CA085265, R25CA090956,
R01CA132839.
MMHS: This work was supported by grants from the National Cancer Institute, National
Institutes of Health, and Department of Health and Human Services. (R01 CA128931, R01 CA
128931-S01, R01 CA97396, P50 CA116201, and Cancer Center Support Grant P30 CA15083).
Breast Cancer Susceptibility Variants and Mammographic Density
6
NBCS: This study has been supported with grants from Norwegian Research Council
(#183621/S10 and #175240/S10), The Norwegian Cancer Society (PK80108002,
PK60287003), and The Radium Hospital Foundation as well as S-02036 from South Eastern
Norway Regional Health Authority.
NHS: This study was supported by Public Health Service Grants CA131332, CA087969,
CA089393, CA049449, CA98233, CA128931, CA 116201, CA 122340 from the National
Cancer Institute, National Institutes of Health, Department of Health and Human Services.
OOA study was supported by CA122822 and X01 HG005954 from the NIH; Breast Cancer
Research Fund; Elizabeth C. Crosby Research Award, Gladys E. Davis Endowed Fund, and the
Office of the Vice President for Research at the University of Michigan. Genotyping services
for the OOA study were provided by the Center for Inherited Disease Research (CIDR), which
is fully funded through a federal contract from the National Institutes of Health to The Johns
Hopkins University, contract number HHSN268200782096.
OFBCR: This work was supported by grant UM1 CA164920 from the USA National Cancer
Institute. The content of this manuscript does not necessarily reflect the views or policies of
the National Cancer Institute or any of the collaborating centers in the Breast Cancer Family
Registry (BCFR), nor does mention of trade names, commercial products, or organizations
imply endorsement by the USA Government or the BCFR.
SASBAC: The SASBAC study was supported by Märit and Hans Rausing’s Initiative against
Breast Cancer, National Institutes of Health, Susan Komen Foundation and Agency for
Science, Technology and Research of Singapore (A*STAR).
Breast Cancer Susceptibility Variants and Mammographic Density
7
SIBS: SIBS was supported by program grant C1287/A10118 and project grants from Cancer
Research UK (grant numbers C1287/8459).
COGS grant: Collaborative Oncological Gene-environment Study (COGS) that enabled the
genotyping for this study. Funding for the BCAC component is provided by grants from the
EU FP7 programme (COGS) and from Cancer Research UK. Funding for the iCOGS
infrastructure came from: the European Community's Seventh Framework Programme
under grant agreement n° 223175 (HEALTH-F2-2009-223175) (COGS), Cancer Research UK
(C1287/A10118, C1287/A 10710, C12292/A11174, C1281/A12014, C5047/A8384,
C5047/A15007, C5047/A10692), the National Institutes of Health (CA128978) and Post-
Cancer GWAS initiative (1U19 CA148537, 1U19 CA148065 and 1U19 CA148112 - the GAMEON
initiative), the Department of Defence (W81XWH-10-1-0341), the Canadian Institutes of
Health Research (CIHR) for the CIHR Team in Familial Risks of Breast Cancer, Komen
Foundation for the Cure, the Breast Cancer Research Foundation, and the Ovarian Cancer
Research Fund.This is the author accepted manuscript. The final version is available via American Association for Cancer Research at http://cancerres.aacrjournals.org/content/early/2015/04/10/0008-5472.CAN-14-2012.abstract
- …