Page 133 - 2014 Printable Abstract Book
P. 133
coming to Emory, I showed that exosomes can carry bystander signals. The main aim of my current work
is to identify and characterize the contents of these exosomes using proteomic and RNA sequencing
technologies. The EJ carcinoma cells were irradiated using 0.3 Gy or 1 Gy using γ-rays. The cells were
incubated for one hour and the conditioned medium was harvested. Exosomes were isolated using
ultracentrifugation approach. Preliminary work has shown that the amount of protein and miRNA in the
exosomal fraction is higher with irradiated cells. Characterization of these proteins and miRNAs is planned.
I will also characterize the physical properties of the exosomes, including the size distribution as estimated
by electron microscopy and dynamic light scattering. Further characterization of these extracellular RNA
and protein profiles will provide insight into bystander signaling and open the doors for the identification
of which components plays crucial roles in mediating radiation-induced bystander effects.
(PS1-58) Suppressed gene expression during prostate acini formation targeting chromosome 1q21
1;2
2
following chronic low dose radiation. J. Tyson McDonald, PhD ; Michael Peluso, BS ; Luisel Ricks-Santi,
1
1
2
PhD ; and Lynn Hlatky, PhD, Hampton Univeristy Cancer Research Center, Hampton, VA and Center of
2
Cancer Systems Biology, GRI, Boston, MA
The full consequence on human health from low dose ionizing radiation exposure is unknown and
experimental studies have not clearly determined the potential impact of low dose exposure on functional
cellular activity. In this study, we have examined the effects of chronic low dose radiation during acini
formation using a total dose of 8 to 13cGy (1.0 to 1.6 cGy per day). The normal prostate epithelial cell line
RPWE1, was placed as single cells into three-dimensional growth conditions on a ‘bed’ of growth factor
reduced matrigel. On day eight, total RNA was collected from five independent experimental replicates of
sham irradiated and treated acini cultures. Genome-wide gene expression was then measured using
human HT12v4 chips and run on the Illumina iScan. Raw data was exported using GenomeStudio followed
by log2 transformed, quantile normalization and corrected for non-biological batch effects using
GenePattern. Differential gene expression was measured using the R/Bioconductor package LIMMA that
-4
identified 203 statistically significant genes compared to the non-irradiated control (p-value < 6.46×10 ,
FDR < 10%). Functional annotation and classification using DAVID revealed a statistically significant
enrichment of genes related to keratinocyte, epidermal and epithelial cellular differentiation from genes
encoding small proline-rich proteins (SPRR4, SPRR1A, SPRR2A, SPRR2E, SPRR2B) and the related genes
late cornified envelope 2B (LCE2B), cystatin A (CSTA) and cornifelin (CNFN). Strikingly, this enrichment was
-3
found to correlate specifically with chromosome 1q21 (32 genes; p-value = 6.9×10 , Fisher Exact test =
-3
4.1×10 ). Similarly, gene set enrichment analysis (GSEA) showed a down-regulation of 54 genes located
on chromosome 1q21 (p-value < 0.001, FWER p-value < 0.001). These gene families are related to the
evolutionarily conserved epidermal differentiation complex including 14 late cornified envelope genes
(LCE), 10 small proline-rich protein genes and 4 S100 calcium binding protein genes. This novel finding
demonstrates the potential impact of constant low dose-rate exposure to influence functional cellular
activity that may specifically alter cellular differentiation. This work was supported by Office of Science
(BER), Department of Energy award DE-SC0002606 (to LH).
(PS1-59) Bystander cell-killing effect mediated by nitric oxide in normal human fibroblasts depends in
1
1
part on irradiation dose but not on radiation quality. Yuichiro Yokota ; Tomoo Funayama ; Hiroko Ikeda 2;
131 | P a g e
is to identify and characterize the contents of these exosomes using proteomic and RNA sequencing
technologies. The EJ carcinoma cells were irradiated using 0.3 Gy or 1 Gy using γ-rays. The cells were
incubated for one hour and the conditioned medium was harvested. Exosomes were isolated using
ultracentrifugation approach. Preliminary work has shown that the amount of protein and miRNA in the
exosomal fraction is higher with irradiated cells. Characterization of these proteins and miRNAs is planned.
I will also characterize the physical properties of the exosomes, including the size distribution as estimated
by electron microscopy and dynamic light scattering. Further characterization of these extracellular RNA
and protein profiles will provide insight into bystander signaling and open the doors for the identification
of which components plays crucial roles in mediating radiation-induced bystander effects.
(PS1-58) Suppressed gene expression during prostate acini formation targeting chromosome 1q21
1;2
2
following chronic low dose radiation. J. Tyson McDonald, PhD ; Michael Peluso, BS ; Luisel Ricks-Santi,
1
1
2
PhD ; and Lynn Hlatky, PhD, Hampton Univeristy Cancer Research Center, Hampton, VA and Center of
2
Cancer Systems Biology, GRI, Boston, MA
The full consequence on human health from low dose ionizing radiation exposure is unknown and
experimental studies have not clearly determined the potential impact of low dose exposure on functional
cellular activity. In this study, we have examined the effects of chronic low dose radiation during acini
formation using a total dose of 8 to 13cGy (1.0 to 1.6 cGy per day). The normal prostate epithelial cell line
RPWE1, was placed as single cells into three-dimensional growth conditions on a ‘bed’ of growth factor
reduced matrigel. On day eight, total RNA was collected from five independent experimental replicates of
sham irradiated and treated acini cultures. Genome-wide gene expression was then measured using
human HT12v4 chips and run on the Illumina iScan. Raw data was exported using GenomeStudio followed
by log2 transformed, quantile normalization and corrected for non-biological batch effects using
GenePattern. Differential gene expression was measured using the R/Bioconductor package LIMMA that
-4
identified 203 statistically significant genes compared to the non-irradiated control (p-value < 6.46×10 ,
FDR < 10%). Functional annotation and classification using DAVID revealed a statistically significant
enrichment of genes related to keratinocyte, epidermal and epithelial cellular differentiation from genes
encoding small proline-rich proteins (SPRR4, SPRR1A, SPRR2A, SPRR2E, SPRR2B) and the related genes
late cornified envelope 2B (LCE2B), cystatin A (CSTA) and cornifelin (CNFN). Strikingly, this enrichment was
-3
found to correlate specifically with chromosome 1q21 (32 genes; p-value = 6.9×10 , Fisher Exact test =
-3
4.1×10 ). Similarly, gene set enrichment analysis (GSEA) showed a down-regulation of 54 genes located
on chromosome 1q21 (p-value < 0.001, FWER p-value < 0.001). These gene families are related to the
evolutionarily conserved epidermal differentiation complex including 14 late cornified envelope genes
(LCE), 10 small proline-rich protein genes and 4 S100 calcium binding protein genes. This novel finding
demonstrates the potential impact of constant low dose-rate exposure to influence functional cellular
activity that may specifically alter cellular differentiation. This work was supported by Office of Science
(BER), Department of Energy award DE-SC0002606 (to LH).
(PS1-59) Bystander cell-killing effect mediated by nitric oxide in normal human fibroblasts depends in
1
1
part on irradiation dose but not on radiation quality. Yuichiro Yokota ; Tomoo Funayama ; Hiroko Ikeda 2;
131 | P a g e
