Approximately 30% of pregnancies after implantation end up in spontaneous abortions, and 50% of them are caused by chromosomal abnormalities. However, the spectrum of genomic copy number variants (CNVs) in products ...Approximately 30% of pregnancies after implantation end up in spontaneous abortions, and 50% of them are caused by chromosomal abnormalities. However, the spectrum of genomic copy number variants (CNVs) in products of conception (POC) and the underlying gene- dosage-sensitive mechanisms causing spontaneous abortions remain largely unknown. In this study, array comparative genornic hybridiza- tion (aCGH) analysis was performed as a salvage procedure for 128 POC culture failure (POC-CF) samples and as a supplemental procedure for 106 POC normal karyotype (POC-NK) samples. Chromosomal abnormalities were detected in 10% of POC-CF and pathogenic CNVs were detected in 3.9% of POC-CF and 5.7% of POC-NK samples. Compiled results from this study and relevant case series through a literature review demonstrated an abnormality detection rate (ADR) of 35% for chromosomal abnormalities in POC-CF samples, 3.7% for pathogenic CNVs in POC-CF samples, and 4.6% for pathogenic CNVs in POC-NK samples. Ingenuity Pathway Analysis (IPA) was performed on the genes from pathogenic CNVs found in POC samples. The denoted primary gene networks suggested that apoptosis and cell proliferation pathways are involved in miscarriage. In summary, a similar spectrum of cytogenomic abnormalities was observed in POC culture success and POC-CF samples. A threshold effect correlating the number of dosage-sensitive genes in a chromosome with the observed frequency of autosomai trisomy is proposed. A rationalized approach using firstly fluorescence in situ hybridization (FISH) testing with probes of chromosomes X/Y/ 18, 13/21, and 15/16/22 for common aneuploidies and polyploidies and secondly aCGH for other cytogenomic abnormalities is recommended for POC-CF samples.展开更多
Objective: Identification of colorectal cancer (CRC) metastasis genes is one of the most important issues in CRC research. For the purpose of mining CRC metastasis-associated genes, an integrated analysis of mJcroa...Objective: Identification of colorectal cancer (CRC) metastasis genes is one of the most important issues in CRC research. For the purpose of mining CRC metastasis-associated genes, an integrated analysis of mJcroarray data was presented, by combined with evidence acquired from comparative genornic hybridization (CGH) data. Methods: Gene expression profile data of CRC samples were obtained at Gene Expression Omnibus (GEO) website. The 15 important chromosomal aberration sites detected by using CGH technology were used for integrated genomic and transcriptomic analysis. Significant Analysis of Microarray (SAM) was used to detect significantly differentially expressed genes across the whole genome. The overlapping genes were selected in their corresponding chromosomal aberration regions, and analyzed by using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Finally, SVM-T-RFE gene selection algorithm was applied to identify ted genes in CRC. Results: A minimum gene set was obtained with the minimum number [14] of genes, and the highest classification accuracy (100%) in both PRI and META datasets. A fraction of selected genes are associated with CRC or its metastasis. Conclusions- Our results demonstrated that integration analysis is an effective strategy for mining cancer- associated genes.展开更多
Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation ...Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation genetic diagnosis(PGD) examine distinct parts of an individua genome, require the development of a custom assay for every patient family, and are time consuming and inefficient. In the last decade technologies for wholegenome amplification(WGA) from single cells have led to innovative strategies for preimplantation testing.Applications of WGA technology can lead to a universa approach that uses single-nucleotide polymorphisms(SNPs) and mutations across the entire genome for the analysis. Single-cell WGA by multiple displacement amplification has enabled a linkage approach to PGD known as "preimplantation genetic haplotyping", as well as microarray-based techniques for preimplantation diagnosis. The use of microarrays in preimplantation diagnosis has provided genome-wide testing for gains or losses of single chromosomes(aneuploidies)or chromosomal segments. Properly designed randomized controlled trials are, however, needed to determine whether these new technologies improve IVF outcomes by increasing implantation rates and decreasing mis-carriage rates. In genotype analysis of single cells, allele dropout occurs frequently at heterozygous loci. Preimplantation testing of multiple cells biopsied from blastocysts, however, can reduce allele dropout rates and increase the accuracy of genotyping, but it allows less time for PGD. Future development of fast SNP microarrays will enable a universal preimplantation testing for aneuploidies, single-gene disorders and unbalanced translocations within the time frame of an IVF cycle.展开更多
To systematically estimate the gene duplication events In closely related species, we have to use comparative genomlc approaches, either through genomlc sequence comparison or comparative genomlc hybridization (CGH)...To systematically estimate the gene duplication events In closely related species, we have to use comparative genomlc approaches, either through genomlc sequence comparison or comparative genomlc hybridization (CGH). Given the scarcity of complete genomlc sequences of plant species, in the present study we adopted an array based CGH to Investigate gene duplications In the genus Arabldopsls. Fragment genomlc DNA from four species, namely Arabidopsls thallana, A. lyrata subsp, lyrata, A. lyrata subsp, petraea, and A. halleri, was hybridized to Affymetrlx (Santa Clara, CA, USA) tiling arrays that are designed from the genomlc sequences of A. thallana. Pairwlse comparisons of signal intensity were made to infer the potential duplicated candidates along each phylogenetic branch. Ninety-four potential candidates of gene duplication along the genus were Identified. Among them, the majority (69 of 94) were A. thallana lineage specific. This result indicates that the array based CGH approach may be used to Identify candidates of duplication In other plant genera containing closely related species, such as Oryza, particularly for the AA genome species. We compared the degree of gene duplication through retrotransposon between O. satlva and A. thallana and found a strikingly higher number of chimera retroposed genes In rice. The higher rate of gene duplication through retroposltlon and other mechanisms may Indicate that the grass species Is able to adapt to more diverse environments.展开更多
Objective: To evaluate p63 expression at mRNA transcripts and protein levels in lung squamous cell cancer (SCC), adenocarcinoma, large cell lung cancer (LCLC) and small cell lung cancer (SCLC) and their matched metast...Objective: To evaluate p63 expression at mRNA transcripts and protein levels in lung squamous cell cancer (SCC), adenocarcinoma, large cell lung cancer (LCLC) and small cell lung cancer (SCLC) and their matched metastatic tumors. The association between p63 expression and p63 locus at chromosomal 3q27 q29 was also investigated. Methods: p63 mRNA expression levels in a large series of lung cancers including SCC, adenocarcinoma, LCLC, SCLC and their matched metastatic tumors were analyzed by cDNA microarray technology. A tissue microarray from 150 primary lung cancer specimens was constructed and used for immunohistochemical detection of p63 protein expression. Chromosomal imbalances at the p63 locus in 70 primary lung cancers samples were studied by comparative genomic hybridization (CGH) technology. Results: mRNA levels were 10 fold in SCC compared to LCLC, SCLC, and adenocarcinoma. Interestingly, the mRNA expression of p63 in metastatic carcinomas was significantly higher than that in their matched primary tumors ( P <0 001). Immunohistochemistry demonstrated that p63 expression was 94.64% in SCC but only 1 79% in lung adenocarcinoma and 2 of 4 LCLC were positive staining. All the results in of SCLC were negative. There was a statistically significant difference for p63 positivity between pT1 tumors and those of higher stage ( P =0 035). The CGH results indicated that p63 locus at chromosomal 3q27 q29 was overrepresented in SCC. p63 immunopositivity correlated significantly with pronounced gains of the p63 locus at chromosomal 3q27 q29 (P=0.0001), indicating that strong expression of p63 in lung SCC correlated with increased gene amplification. Conclusion: p63 might play an important role not only in squamous differentiation of lung cancer but also in tumor development and progression.展开更多
The short report will be focused on helping our students to understand commonly used conventional and cutting edge cytogenetic techniques and their clinical applications, the advances and drawbacks of each technique, ...The short report will be focused on helping our students to understand commonly used conventional and cutting edge cytogenetic techniques and their clinical applications, the advances and drawbacks of each technique, and how to pick the right test(s) for a specific patient in order to achieve a proper diagnosis efficiently and economically.展开更多
The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. T...The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. They will also review presymptomatic testing of hereditary cancers, and the application of expression profiling to identify patients likely to benefit from particular therapeutic approaches.展开更多
基金partially supported by Guangdong Innovative and Entrepreneurial Research Team Program (No. 201301S0105240297)by 111 Project
文摘Approximately 30% of pregnancies after implantation end up in spontaneous abortions, and 50% of them are caused by chromosomal abnormalities. However, the spectrum of genomic copy number variants (CNVs) in products of conception (POC) and the underlying gene- dosage-sensitive mechanisms causing spontaneous abortions remain largely unknown. In this study, array comparative genornic hybridiza- tion (aCGH) analysis was performed as a salvage procedure for 128 POC culture failure (POC-CF) samples and as a supplemental procedure for 106 POC normal karyotype (POC-NK) samples. Chromosomal abnormalities were detected in 10% of POC-CF and pathogenic CNVs were detected in 3.9% of POC-CF and 5.7% of POC-NK samples. Compiled results from this study and relevant case series through a literature review demonstrated an abnormality detection rate (ADR) of 35% for chromosomal abnormalities in POC-CF samples, 3.7% for pathogenic CNVs in POC-CF samples, and 4.6% for pathogenic CNVs in POC-NK samples. Ingenuity Pathway Analysis (IPA) was performed on the genes from pathogenic CNVs found in POC samples. The denoted primary gene networks suggested that apoptosis and cell proliferation pathways are involved in miscarriage. In summary, a similar spectrum of cytogenomic abnormalities was observed in POC culture success and POC-CF samples. A threshold effect correlating the number of dosage-sensitive genes in a chromosome with the observed frequency of autosomai trisomy is proposed. A rationalized approach using firstly fluorescence in situ hybridization (FISH) testing with probes of chromosomes X/Y/ 18, 13/21, and 15/16/22 for common aneuploidies and polyploidies and secondly aCGH for other cytogenomic abnormalities is recommended for POC-CF samples.
基金supported by a grant from the National Natural Science Foundation of China(Grant No.61373057)a grant from the Zhejiang Provincial Natural Science Foundation of China(Grant No.Y1110763)
文摘Objective: Identification of colorectal cancer (CRC) metastasis genes is one of the most important issues in CRC research. For the purpose of mining CRC metastasis-associated genes, an integrated analysis of mJcroarray data was presented, by combined with evidence acquired from comparative genornic hybridization (CGH) data. Methods: Gene expression profile data of CRC samples were obtained at Gene Expression Omnibus (GEO) website. The 15 important chromosomal aberration sites detected by using CGH technology were used for integrated genomic and transcriptomic analysis. Significant Analysis of Microarray (SAM) was used to detect significantly differentially expressed genes across the whole genome. The overlapping genes were selected in their corresponding chromosomal aberration regions, and analyzed by using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Finally, SVM-T-RFE gene selection algorithm was applied to identify ted genes in CRC. Results: A minimum gene set was obtained with the minimum number [14] of genes, and the highest classification accuracy (100%) in both PRI and META datasets. A fraction of selected genes are associated with CRC or its metastasis. Conclusions- Our results demonstrated that integration analysis is an effective strategy for mining cancer- associated genes.
基金Supported by Department of Pediatrics,Medical College of Wisconsin,Milwaukee,WI,United States
文摘Preimplantation genetic testing refers to the procedure to determine the genetic status of embryos formed by in vitro fertilization(IVF) prior to initiating a pregnancy.Traditional genetic methods for preimplantation genetic diagnosis(PGD) examine distinct parts of an individua genome, require the development of a custom assay for every patient family, and are time consuming and inefficient. In the last decade technologies for wholegenome amplification(WGA) from single cells have led to innovative strategies for preimplantation testing.Applications of WGA technology can lead to a universa approach that uses single-nucleotide polymorphisms(SNPs) and mutations across the entire genome for the analysis. Single-cell WGA by multiple displacement amplification has enabled a linkage approach to PGD known as "preimplantation genetic haplotyping", as well as microarray-based techniques for preimplantation diagnosis. The use of microarrays in preimplantation diagnosis has provided genome-wide testing for gains or losses of single chromosomes(aneuploidies)or chromosomal segments. Properly designed randomized controlled trials are, however, needed to determine whether these new technologies improve IVF outcomes by increasing implantation rates and decreasing mis-carriage rates. In genotype analysis of single cells, allele dropout occurs frequently at heterozygous loci. Preimplantation testing of multiple cells biopsied from blastocysts, however, can reduce allele dropout rates and increase the accuracy of genotyping, but it allows less time for PGD. Future development of fast SNP microarrays will enable a universal preimplantation testing for aneuploidies, single-gene disorders and unbalanced translocations within the time frame of an IVF cycle.
基金Supported by Fellowships from the Pew Latin American Fellows Program and Conselho Nacional de Desenvolvimento Cientfico e Tecnologico (to MDV), the USA National Science Foundation CAREER award (MCB0238168) and USA National Institutes of Health R01 grants (R01GM065429-01A1 and GM078070-01A1) to ML at the University of Chicago. Publication of this paper is supported by the National Natural Science Foundation of China (30624808).Acknowledgements The authors thank Dr Hedibert F. Lopes (University of Chicago, Graduate School of Business, Chicago, USA) for his discussions regarding the statistical methods, Noboru Jo Sakabe (IQ- USP/LICR-Sao Paulo Branch, Sao Paulo, Brazil) for critical reading of the manuscript. The authors also thank those people who provided seed samples of Arabidopsis: ABRC Stock Center (The 0hio State University, Columbus, 0H 43210, USA), Justin Borevitz (Department of Ecology and Evolution, The University of Chicago, Chicago, Illinois 60637, USA), Daphne Preuss (Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA), Joy Bergelson (Department of Ecology and Evolution, The University of Chicago, Chicago, Illinois 60637, USA), and Mark MacNair (Department of Biological Sciences, University of Exeter, Exeter, EX4 6EZ, UK).
文摘To systematically estimate the gene duplication events In closely related species, we have to use comparative genomlc approaches, either through genomlc sequence comparison or comparative genomlc hybridization (CGH). Given the scarcity of complete genomlc sequences of plant species, in the present study we adopted an array based CGH to Investigate gene duplications In the genus Arabldopsls. Fragment genomlc DNA from four species, namely Arabidopsls thallana, A. lyrata subsp, lyrata, A. lyrata subsp, petraea, and A. halleri, was hybridized to Affymetrlx (Santa Clara, CA, USA) tiling arrays that are designed from the genomlc sequences of A. thallana. Pairwlse comparisons of signal intensity were made to infer the potential duplicated candidates along each phylogenetic branch. Ninety-four potential candidates of gene duplication along the genus were Identified. Among them, the majority (69 of 94) were A. thallana lineage specific. This result indicates that the array based CGH approach may be used to Identify candidates of duplication In other plant genera containing closely related species, such as Oryza, particularly for the AA genome species. We compared the degree of gene duplication through retrotransposon between O. satlva and A. thallana and found a strikingly higher number of chimera retroposed genes In rice. The higher rate of gene duplication through retroposltlon and other mechanisms may Indicate that the grass species Is able to adapt to more diverse environments.
文摘Objective: To evaluate p63 expression at mRNA transcripts and protein levels in lung squamous cell cancer (SCC), adenocarcinoma, large cell lung cancer (LCLC) and small cell lung cancer (SCLC) and their matched metastatic tumors. The association between p63 expression and p63 locus at chromosomal 3q27 q29 was also investigated. Methods: p63 mRNA expression levels in a large series of lung cancers including SCC, adenocarcinoma, LCLC, SCLC and their matched metastatic tumors were analyzed by cDNA microarray technology. A tissue microarray from 150 primary lung cancer specimens was constructed and used for immunohistochemical detection of p63 protein expression. Chromosomal imbalances at the p63 locus in 70 primary lung cancers samples were studied by comparative genomic hybridization (CGH) technology. Results: mRNA levels were 10 fold in SCC compared to LCLC, SCLC, and adenocarcinoma. Interestingly, the mRNA expression of p63 in metastatic carcinomas was significantly higher than that in their matched primary tumors ( P <0 001). Immunohistochemistry demonstrated that p63 expression was 94.64% in SCC but only 1 79% in lung adenocarcinoma and 2 of 4 LCLC were positive staining. All the results in of SCLC were negative. There was a statistically significant difference for p63 positivity between pT1 tumors and those of higher stage ( P =0 035). The CGH results indicated that p63 locus at chromosomal 3q27 q29 was overrepresented in SCC. p63 immunopositivity correlated significantly with pronounced gains of the p63 locus at chromosomal 3q27 q29 (P=0.0001), indicating that strong expression of p63 in lung SCC correlated with increased gene amplification. Conclusion: p63 might play an important role not only in squamous differentiation of lung cancer but also in tumor development and progression.
文摘The short report will be focused on helping our students to understand commonly used conventional and cutting edge cytogenetic techniques and their clinical applications, the advances and drawbacks of each technique, and how to pick the right test(s) for a specific patient in order to achieve a proper diagnosis efficiently and economically.
文摘The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. They will also review presymptomatic testing of hereditary cancers, and the application of expression profiling to identify patients likely to benefit from particular therapeutic approaches.