Project description:The human pathogen Streptococcus pyogenes, or group A streptococcus, is responsible for mild infections to life-threatening diseases. To determine the primary transcriptome of the emm1 strain S119, we have performed a differential RNA-Seq experiment based on selective Tobacco Acid Pyrophosphatase (TAP) treatment and 5' adapter ligation to differentiate primary transcripts (5' tri-phosphate) and processed RNAs (5' mono-phosphate). The libraries were performed on a mixture of RNAs prepared from bacteria cultured to late exponential phase in a rich growth culture medium supplemented or not with 15 mM of MgCl2
Project description:The human pathogen Streptococcus pyogenes, or group A streptococcus, is responsible for mild infections to life-threatening diseases. We previously have performed the transcription start site profiling of a Streptococcus pyogenes emm1 strain, strain S119, an invasive strain isolated from a blood culture. Here, we perform strand-specific RNA-seq experiments to complete this characterization and analyze the global coverage and the differential expression in growth medium complemented or not with 15 mM MgCl2. In addition we compare these results to those obtained with a related strain, strain S126, corresponding to a colonization sample, that differs from S119 by only one mutation in the two-component regulator of virulence CovRS.
Project description:In this study, we sought to indentify stable individual traits in developing metastatic melanoma, assess their stability in time, and analyze typical dynamics and common trends of genomic changes in individual cases of late stage metastatic cancer. To this end, we compared consecutive recurrent metastases developed by a special group of eight individuals with advanced metastatic melanoma, all developing several recurrent metastases over several months to years of natural disease evolution.
Project description:In this study, we sought to indentify stable individual traits in developing metastatic melanoma, assess their stability in time, and analyze typical dynamics and common trends of genomic changes in individual cases of late stage metastatic cancer. To this end, we compared consecutive recurrent metastases developed by a special group of eight individuals with advanced metastatic melanoma, all developing several recurrent metastases over several months to years of natural disease evolution.
Project description:To define clonal evolution of somatic copy number alterations (CNAs) in chronic lymphocytic leukemia (CLL), sequential samples of 103 individuals were investigated by SNP-array analysis for appearance of novel CNAs. Patients were enrolled on the CLL8 trial and uniformly received fludarabine, cyclophosphamide +/- rituximab (FC/FCR). Comparing two sequential samples prior to therapy (N=27, a median of 2.9 years apart), CNA evolution occurred in 19% of cases. In contrast, when comparing treatment‑initiation and relapse genomic profiles (a median of 3.6 years apart), CNA evolution was seen in 40% of cases. This suggested association of FC(R) treatment with higher rate of CNA evolution. The only clinical feature significantly associated with CNA evolution was FCR therapy compared with FC (OR=2.806, p=0.024). As this might be related to narrower evolutionary bottlenecks imposed by the more effective FCR therapy, which could execute more selection pressure, we examined matched minimal residual disease data. We found CNA evolution more frequently in cases with CLL cell numbers rapidly receding in early phases of treatment. Finally, we observed frequent rises of TP53 mutant/deficient clones with therapy (N=19, 22%) that were associated with decreased overall survival (p=0.016). These results demonstrated that re-examination of TP53 status upon relapse provides important information.
Project description:This is a genomic analysis of breast cancer metastasis using array based CGH and is part of a large study investigating the patterns and evolution of metastases from breast cancer using autopsy material accumulated over the last 50 years from a single institution. The samples used in the genomic profiling comprise the primary breast tumour and multiple matched metastases from each patient. The data demonstrate both the clonal nature of metastatic progression and the role of clonal evolution during progression.