Project description:We studied 277 lymphoma samples (198 FL and 79 transformed FL [tFL]) using a single-nucleotide polymorphism array to identify the secondary chromosomal abnormalities that drive the development of FL and its transformation to diffuse large B-cell lymphoma. Affymetrix 250K NspI SNP arrays were performed according to the manufacturer's directions on DNA extracted from frozen follicular lymphoma or transformed follicular lymphoma tumor specimens
Project description:Follicular lymphoma (FL) is the second most common B-cell malignancy representing one quarter of Non-Hodgkin's Lymphomas. Although the disease has a relatively long median survival, the illness follows a fluctuating course of progression punctuated by remissions of variable duration. For as many as half of patients, transformation to a more aggressive lymphoma (t-FL) may occur; this event is often associated with a particularly poor response to treatment. SNP analysis has revealed the presence of large regions of homozygosity in the absence of copy number change. These events can result in the selection of of daughter cells made homozygous for a pre-existing mutation. We have used SNPs array technology to investigate regions of loss of hetrozygosity in the absence of copy number change in order to establish the contribution of these abnormalities to the evolution of FL and t-FL. Experiment Overall Design: DNA from 26 pairs of follicular and transformed follicular lymphoma samples and 3 cell lines were analysed using Affymetrix 10K SNP arrays. The genotype data of transformed follicular lymphoma samples were compared with the data from the corresponding follicular lymphoma sample.
Project description:Follicular lymphoma is the most common indolent non-Hodgkin's lymphoma involving germinal centre B cells, with a subset of patients undergoing transformation to a diffuse large B-cell lymphoma (DLBCL) morphology for which the clinical outcomes are poor. To elucidate the differences in copy number profiles between FL and tFL groups, we performed Affymetrix SNP 6.0 Array analysis on 31 paired FL-tFL cases. We wanted to identify and compare recurrent somatic copy number alterations (CNAs) between the two groups (FL vs. tFL). In addition, the concordance and discordance in the copy neutral loss of heterozygosity (cnLOH) between the two groups were also investigated to identify recurrent target gene regions. Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from follicular lymphoma (FL), transformed follicular lymphoma (tFL) and matching germline (GL) sample (if available). Copy number analysis of Affymetrix SNP 6.0 Array were performed on 91 DNA samples, consisting of 31 patients. Among the 31 patients, 19 had matching germline samples, while 12 had no germline samples. The Log R Ratio (LRR) values and the B Allele Frequency (BAF) values were subsequently calculated to search for copy number aberrations and copy neutral (CN)-LOH in the FL and tFL samples. Paired and unpaired analyses were performed accordingly.
Project description:Comparison of gene expression profiles from diagnostic samples of diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) to a patient case withsamples of primary and relapsed transformed FL.
Project description:Comparison of gene expression profiles from diagnostic samples of diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) to a patient case withsamples of primary and relapsed transformed FL
