Project description:Comparative oncology is a developing research discipline that is being used to assist our understanding of human neoplastic diseases. Companion canines are a preferred animal oncology model due to spontaneous tumor development and similarity to human disease at the pathophysiological level. We use a paired RNA sequencing (RNA-Seq)/microarray analysis of a set of four normal canine lymph nodes and ten canine lymphoma fine needle aspirates to identify technical biases and variation between the technologies and convergence on biological disease pathways. Surrogate Variable Analysis (SVA) provides a formal multivariate analysis of the combined RNA-Seq/microarray data set. Applying SVA to the data allows us to decompose variation into contributions associated with transcript abundance, differences between the technology, and latent variation within each technology. A substantial and highly statistically significant component of the variation reflects transcript abundance, and RNA-Seq proved more sensitive for detection of transcripts expressed at low levels. Latent random variation among RNA-Seq samples is also distinct in character from that impacting microarray samples. In particular, we observed variation between RNA-Seq samples that reflects transcript GC content. Platform-independent variable decomposition without a priori knowledge of the sources of variation using SVA represents a generalizable method for accomplishing cross-platform data analysis. We identified genes differentially expressed between normal lymph nodes of disease free dogs and a subset of the diseased dogs diagnosed with B-cell lymphoma using each technology. There is statistically significant overlap between the RNA-Seq and microarray sets of differentially expressed genes. Analysis of overlapping genes in the context of biological systems suggests elevated expression and activity of PI3K signaling in B-cell lymphoma biopsies compared with normal biopsies, consistent with literature describing successful use of drugs targeting this pathway in lymphomas.
Project description:Comparative oncology is a developing research discipline that is being used to assist our understanding of human neoplastic diseases. Companion canines are a preferred animal oncology model due to spontaneous tumor development and similarity to human disease at the pathophysiological level. We use a paired RNA sequencing (RNA-Seq)/microarray analysis of a set of four normal canine lymph nodes and ten canine lymphoma fine needle aspirates to identify technical biases and variation between the technologies and convergence on biological disease pathways. Surrogate Variable Analysis (SVA) provides a formal multivariate analysis of the combined RNA-Seq/microarray data set. Applying SVA to the data allows us to decompose variation into contributions associated with transcript abundance, differences between the technology, and latent variation within each technology. A substantial and highly statistically significant component of the variation reflects transcript abundance, and RNA-Seq proved more sensitive for detection of transcripts expressed at low levels. Latent random variation among RNA-Seq samples is also distinct in character from that impacting microarray samples. In particular, we observed variation between RNA-Seq samples that reflects transcript GC content. Platform-independent variable decomposition without a priori knowledge of the sources of variation using SVA represents a generalizable method for accomplishing cross-platform data analysis. We identified genes differentially expressed between normal lymph nodes of disease free dogs and a subset of the diseased dogs diagnosed with B-cell lymphoma using each technology. There is statistically significant overlap between the RNA-Seq and microarray sets of differentially expressed genes. Analysis of overlapping genes in the context of biological systems suggests elevated expression and activity of PI3K signaling in B-cell lymphoma biopsies compared with normal biopsies, consistent with literature describing successful use of drugs targeting this pathway in lymphomas. RNA was extracted from 10 lymphoma fine needle aspirates attained from companion canines. 4 normal lymph node samples were obtained from a Beagle breeding colony at Pfizer, including two samples that were taken from the same dog but different lymph nodes. This Series represents the Affymetrix gene expression only, not RNA-Seq referenced above. RNA-Seq data have been submitted to SRA as SRA059558.
Project description:Molecular mechanisms of the cancer cells-macrophages interactions growing in vitro conditions as a co-culture. The five canine mammary cancer cell lines were cultured with monocytes sorted from the canine blood for 72hrs. Then, the cancer cells and macrophages were sorted and the gene expression analysis was conducted. The control for each co-cultured cell line was the same cell line growing as a single culture, whereas the control for the macrophages growing in a co-culture conditions were macrophages growing as a single culture. Solid tumors are comprised of various cells, like cancer cells, resident stromal cells, migratory hemopoietic cells and so on. These cells regulate tumor growth and metastasis. Macrophages are probably the most important element of the interactions within the tumor microenvironment. However, the molecular mechanism how the tumor environment can educate tumor-associated macrophages (TAMs) toward a tumor-promoting phenotype still remains unknown. Moreover, there are no information how the presence of macrophages change the cancer cells phenotype. Exploring the underlying molecular mechanisms of these phenomena was the aim of this study. Solid tumors are comprised of various cells, like cancer cells, resident stromal cells, migratory hemopoietic cells and so on. These cells regulate tumor growth and metastasis. Macrophages are probably the most important element of the interactions within the tumor microenvironment. However, the molecular mechanism how the tumor environment can educate tumor-associated macrophages (TAMs) toward a tumor-promoting phenotype still remains unknown. Moreover, there are no information how the presence of macrophages change the cancer cells phenotype. Exploring the underlying molecular mechanisms of these phenomena was the aim of this study. Dye-swap experiment, each cell line growing in the co-culture conditions was compared to the same cell line growing as a single culture, macrophages growing in the co-culture conditions were compared to the macrophages growing as the single culture.