Project description:A standard Affymetrix SNP6.0 assay was performed on the tumour samples of patients where we have exonic sequence data from both the tumour and normal DNA of the same patients. The resulting cellularity, copy number and ploidy information generated helped to inform bespoke algorithms in analysing the sequence data.
Project description:Copy number profile of cultured Breast Cancer cell line measured by Affymetrix SNPs microarrays Whole genome copy number profile of 2 breast cancer cell lines were analyzed using Affymetrix SNP6.0 arrays
Project description:We performed a comparison analysis of the Affymetrix arrays SNP6.0 genome wide array (SNP6.0) and cytogenetic 2.7M whole-genome array (Cyto2.7M) using nine human samples. We compared the two array types with respect to four parameters including the size and breakpoints of the alterations detected, the actual CN assigned to the CNVs as well as long stretches of loss of heterozygosity. Overall, we found very good consistency between the two types of array on all parameters compared, even in regions with very complex changes. This GEO submission contains the Cyto2.7M data. GEO submission, GSE37977 contains the SNP6.0 data.
Project description:We performed a comparison analysis of the Affymetrix arrays SNP6.0 genome wide array (SNP6.0) and cytogenetic 2.7M whole-genome array (Cyto2.7M) using nine human samples. We compared the two array types with respect to four parameters including the size and breakpoints of the alterations detected, the actual CN assigned to the CNVs as well as long stretches of loss of heterozygosity. Overall, we found very good consistency between the two types of array on all parameters compared, even in regions with very complex changes. This GEO submission contains the SNP6.0 data. GEO submission, GSE37978 contains the Cyto2.7M data.
Project description:We analyzed the miRNA expression in 6 breast cancer cell lines from young (HCC1500, HCC1937) and old (MCF-7, MDA-MB-231, HCC1806 and MDA-MB-468) patients with breast cancer using the GeneChip® miRNA 2.0 Array (Affymetrix, Santa Clara, CA, USA).
Project description:Cancer evolves dynamically, as clonal expansions supersede or overlap one another, driven by shifting selective pressures, mutational processes and disrupted cancer genes. These processes mark the genome, such that a cancerÕs life history is encrypted in the timing, ploidy, clonality and patterns of somatic mutation. We developed bioinformatic algorithms to decipher this narrative, and applied them to 21 breast cancer genomes. We find that mutational processes evolve across the lifespan of a breast tumor, with cancer-specific signatures of point mutations and chromosomal instability often emerging late but contributing extensive genetic variation. Subclonal diversification is prominent, providing insight into the dynamics of clonal expansion in breast cancer. Most point mutations are found in just a fraction of tumor cells, together with frequent variegation in chromosomal copy number. Every tumor studied here has a dominant subclonal lineage, representing more than 50% of tumor cells. Minimal expansion of these subclones occurs until many hundreds to thousands of mutations have accumulated, implying the existence of long-lived, quiescent lineages of cells that are capable of substantial proliferation upon acquisition of enabling genomic changes. Expansion of the dominant subclone to an appreciable mass may therefore represent the final rate-limiting step in a breast cancer's development, triggering diagnosis.