Project description:Evaluation of four commercial high-resolution oligonucleotide microarray platforms, Affymetrix Genome-Wide Human SNP Array 6.0, Agilent Human Genome CGH 244A, Illumina HumanExon510s-duo and Nimblegen HG18 CGH 385k WG tiling v1.0, for genomic profiling of bone tumours.
Project description:Malignant melanoma is an aggressive heterogeneous disease for which new biomarkers for diagnosis and clinical outcome are needed. We investigated by array-CGH the presence of DNA gains and losses to provide better genomic profile of primary malignant melanoma and to explore the possibility to distinguish metastatic from non metastatic melanomas using this technology. High resolution array-CGH (Agilent Technologies, Palo Alto, CA), with more than 40.000 probes, has been used to analyze 20 frozen tissues of vertical growth phase primary melanoma with a minimum follow-up time of 36 months. Eight patients developed nodal metastatic disease and twelve did not. For results validation, 83 additional melanoma samples with similar clinical characteristics were analysed by FISH. DNA copy number aberrations (CNA) were observed in 19 out of 20 cases. The most frequent changes were complete or partial losses in chromosomes 9 (12 cases, 60%) and 10 (9 cases, 45%), partial gains or trisomies of chromosome 7 (10 cases, 50%); and monosomy of chromosome 19 (7 cases, 35%). Sixty-four recurrent aberrant regions (SORIs) were precisely delimited and used as variables for clustering. Unsupervised Cluster analysis allowed the segregation of samples into two genomic groups that naturally fitted with the metastatic condition of the cases. Four of these aberrant regions were chosen for their biological interest and were confirmed as aberrant using FISH technique on fixed paraffin embedded tissues. Conclusion: Supervised classification allowed obtaining aberrations useful to separate samples with different clinical outcome. Obtained results are useful to improve the knowledge about melanoma tumorigenesis but unfortunately cannot be used as a marker for metastatic progression. Keywords: Comparative Genomic Hybridization - array; Genomic Instability
Project description:Malignant melanoma is an aggressive heterogeneous disease for which new biomarkers for diagnosis and clinical outcome are needed. We investigated by array-CGH the presence of DNA gains and losses to provide better genomic profile of primary malignant melanoma and to explore the possibility to distinguish metastatic from non metastatic melanomas using this technology. High resolution array-CGH (Agilent Technologies, Palo Alto, CA), with more than 40.000 probes, has been used to analyze 20 frozen tissues of vertical growth phase primary melanoma with a minimum follow-up time of 36 months. Eight patients developed nodal metastatic disease and twelve did not. For results validation, 83 additional melanoma samples with similar clinical characteristics were analysed by FISH. DNA copy number aberrations (CNA) were observed in 19 out of 20 cases. The most frequent changes were complete or partial losses in chromosomes 9 (12 cases, 60%) and 10 (9 cases, 45%), partial gains or trisomies of chromosome 7 (10 cases, 50%); and monosomy of chromosome 19 (7 cases, 35%). Sixty-four recurrent aberrant regions (SORIs) were precisely delimited and used as variables for clustering. Unsupervised Cluster analysis allowed the segregation of samples into two genomic groups that naturally fitted with the metastatic condition of the cases. Four of these aberrant regions were chosen for their biological interest and were confirmed as aberrant using FISH technique on fixed paraffin embedded tissues. Conclusion: Supervised classification allowed obtaining aberrations useful to separate samples with different clinical outcome. Obtained results are useful to improve the knowledge about melanoma tumorigenesis but unfortunately cannot be used as a marker for metastatic progression. Experiment Overall Design: Comparative experiment: pheripheral blood pool of ten healthy female donors: CONTROL vs. 20 Primary Vertigal Growth Phase Melanoma samples.
Project description:DNA samples of haploid ES cells and control DNA were compared to genomic DNA of the C57B/6 inbred mouse strain on a NimbleGen Mouse CGH 3x720K Whole-Genome Tiling Array (Build MM9), (GPL10989) DNA samples of haploid ES cells and control DNA were compared to genomic DNA of the 129/Sv inbred mouse strain on a NimbleGen Mouse CGH 3x720K Whole-Genome Tiling Array (Build MM9), (GPL10989)
Project description:The identification of genomic alterations occurring in neoplastic lesions provides insight into both lesion occurrence and disease progression. In this study we used microarray comparative genomic hybridization (CGH) to investigate genetic changes in atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS), as the presence of these lobular neoplastic lesions is an indicator of risk in the development of invasive breast cancer. DNA was extracted from microdissected archival breast tissue containing ALH or LCIS, lacking adjacent invasive carcinoma, and subjected to whole-genome tiling path microarray-CGH using the submegabase resolution tiling set (SMRTr)-array platform. Twelve ALH and 13 LCIS lesions were examined. Copy number alterations were identified using statistical criteria and validated with Real-Time PCR and fluorescence in situ hybridization. From statistical analysis, a greater number of alterations were observed in ALH compared to LCIS. Alterations common to ALH include gain at 2p11.2 and loss at 7p11.2-p11.1 and 22q11.1. Alterations common to LCIS include gain at 20q13.13 and loss at 19q13.2-q13.31. In both ALH and LCIS, we observed loss of 16q21-q23.1, an altered region previously identified in lobular neoplasia and invasive carcinoma. The validation of select alterations reinforces the genomic signature. This study represents the first whole-genome investigation of lobular neoplastic breast lesions using clinical archival specimens. The identified genomic signature includes copy number alterations not previously identified for lobular neoplasia. This genomic signature, common to ALH and LCIS, suggests a role for the acquisition of novel genomic alterations in the aberrant cellular proliferation that defines lobular neoplasia. Keywords: comparative genomic hybridization, high resolution analysis of atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS) human archival breast lesions by whole genome tiling path array CGH