Project description:Background: Prostate cancer is the second leading cause of cancer mortality among US men. Epidemiological evidence suggests that high vitamin D status protects men from prostate cancer and the active form of vitamin D, 1α,25 dihydroxyvitamin D3 (1,25(OH)2D) has anti-cancer effects in cultured prostate cells. Still, the molecular mechanisms and the gene targets for vitamin D-mediated prostate cancer prevention are unknown. Results: We examined the effect of 1,25(OH)2D (+/- 100 nM, 6, 24, 48 h) on the transcript profile of proliferating RWPE1 cells, an immortalized, non-tumorigenic prostate epithelial cell line that is growth arrested by 1,25(OH)2D (Affymetrix U133 Plus 2.0, n=4/treatment per time and dose). Our analysis revealed many transcript level changes at a 5% false detection rate: 6 h, 1571 (61% up), 24 h, 1816 (60 % up), 48 h, 3566 (38 % up). 288 transcripts were regulated similarly at all time points (182 up, 80 down) and many of the promoters for these transcripts contained putative vitamin D response elements. Functional analysis by pathway or Gene Set Analysis revealed early suppression of WNT, Notch, NF-kB, and IGF1 signaling. Transcripts related to inflammation were suppressed at 6 h (e.g. IL-1 pathway) and suppression of proinflammatory pathways continued at later time points (e.g. IL-17 and IL-6 pathways). There was also evidence for induction of anti-angiogenic pathways and induction of transcripts for protection from oxidative stress or maintenance of cell redox homeostasis at 6 h. Conclusions: Our data reveal of large number of potential new, direct vitamin D target genes relevant to prostate cancer prevention. In addition, our data suggests that rather than having a single strong regulatory effect, vitamin D orchestrates a pattern of changes within prostate epithelial cells that limit or slow carcinogenesis. Experiment Overall Design: RWPE1 cells were treated with medium containing 100 nM of 1,25(OH)2D or vehicle (0.1% ethanol) for 6, 24 or 48 hours (n=4 per treatment, 24 total samples). The transcripts levels in each sample were measured by using the Affymetrix HU133 plus 2.0 GeneChip (Affymetrix, Santa Clara, CA).
Project description:Heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNPC1/C2) functions as an RNA splicing regulator through co-transcriptional association with nascent mRNA. HnRNPC1/C2 can also bind to double-stranded DNA as a vitamin D response element-binding protein (VDRE-BP), thereby regulating transcriptional activity of the vitamin D receptor (VDR) bound to 1,25-dihydroxyvitamin D (1,25(OH)2D). In this way hnRNPC1/C2 may act as a coupling factor for 1,25(OH)2D-directed transcription and RNA splicing. Studies using MG63 osteoblastic cells confirmed that 1,25(OH)2D-VDR mediated induction of the gene for the enzyme 24-hydroxylase (CYP24A1), involved CYP24A1-specific chromatin and RNA immunoprecipitation of hnRNPC1/C2. Furthermore, small interfering (siRNA) knockdown of hnRNPC1/C2 in MG63 cells and was associated with dysregulated expression of CYP24A1 and an alternatively spliced form of CYP24A1 (CYP24A1-variant 2). Genome-wide analysis of RNA expression and alternative splicing indicated that dual role of hnRNPC1/C2 in directing 1,25(OH)2D-mediated gene expression is not restricted to the classical VDR-target CYP24A1. Knockdown of hnRNPC1/C2 resulted in 3500 differentially expressed genes (DEG), and treatment with 1,25(OH)2D 324 DEG. A further 87 DEG were only observed in 1,25(OH)2D-treated cells in hnRNPC1/C2 knockdown cells. HnRNPC1/C2 knockdown or 1,25(OH)2D treatment also induced alternative splicing (AS) (5039 and 310 AS events respectively). Combined hnRNPC1/C2 knockdown and 1,25(OH)2D treatment resulted in significant overlap between DEG and AS genes, but this was not observed for 1,25(OH)2D treatment alone. These data indicate that hnRNPC1/C2 can act to couple transcriptional and splicing responses to 1,25(OH)2D by binding to both DNA and RNA. Similar mechanisms may also exist for other members of the hnRNP and steroid receptor family.
Project description:gene expression profiling by RNA-seq in THP-1 cells treated with 1,25(OH)2D3 for 2.5-24 h three independent experiments of 1,25(OH)2D3 time course in THP-1 cells
Project description:Assessment of regions of open chromatin by FAIRE-seq in THP-1 cells treated with 1,25(OH)2D3 for 0-48 h Three independent experiments of 1,25(OH)2D3 time course in THP-1 cells
Project description:Human testicular cells were isolated mechanically and enzymatically from testis of braindead donors and from urological samples. The expression of genes was studied at baseline and 1,25(OH)2D treated conditions. We used microarrays to analyze the gene expression underlying vitamin D metabolism in human testis cells and identified distinct classes of up-regulated genes during this process. Testicular primary cells were treated with 100nM 1,25(OH)2D for 24h and gene expression studied by microarray on transcript level.
Project description:Background: Prostate cancer is the second leading cause of cancer mortality among US men. Epidemiological evidence suggests that high vitamin D status protects men from prostate cancer and the active form of vitamin D, 1α,25 dihydroxyvitamin D3 (1,25(OH)2D) has anti-cancer effects in cultured prostate cells. Still, the molecular mechanisms and the gene targets for vitamin D-mediated prostate cancer prevention are unknown. Results: We examined the effect of 1,25(OH)2D (+/- 100 nM, 6, 24, 48 h) on the transcript profile of proliferating RWPE1 cells, an immortalized, non-tumorigenic prostate epithelial cell line that is growth arrested by 1,25(OH)2D (Affymetrix U133 Plus 2.0, n=4/treatment per time and dose). Our analysis revealed many transcript level changes at a 5% false detection rate: 6 h, 1571 (61% up), 24 h, 1816 (60 % up), 48 h, 3566 (38 % up). 288 transcripts were regulated similarly at all time points (182 up, 80 down) and many of the promoters for these transcripts contained putative vitamin D response elements. Functional analysis by pathway or Gene Set Analysis revealed early suppression of WNT, Notch, NF-kB, and IGF1 signaling. Transcripts related to inflammation were suppressed at 6 h (e.g. IL-1 pathway) and suppression of proinflammatory pathways continued at later time points (e.g. IL-17 and IL-6 pathways). There was also evidence for induction of anti-angiogenic pathways and induction of transcripts for protection from oxidative stress or maintenance of cell redox homeostasis at 6 h. Conclusions: Our data reveal of large number of potential new, direct vitamin D target genes relevant to prostate cancer prevention. In addition, our data suggests that rather than having a single strong regulatory effect, vitamin D orchestrates a pattern of changes within prostate epithelial cells that limit or slow carcinogenesis.
Project description:To profile the changes in the pattern of gene expression in human OCa cells induced by 1,25(OH)2D3, OVCAR3 cells were treated with 0.1 pM 1,25(OH)2D3 for 0, 8, 24 and 72 h. The cells were harvested, RNA was extracted, and Affmetrix microarrays were hybridized. OVCAR3 cells were treated with 0.1 pM 1,25(OH)2D3 for 0, 8, 24 and 72 hours. 1,25(OH)2D3 was added at different times to allow the treated cells to be harvested at the same time. Ethanol was included as vehicle controls and all cells were exposed to the same amount of ethanol for the same length of time. Total RNA was extracted using Trizol reagent (Invitrogen) and purified using Qiagen Rneasy kit as recommended by Affymetrix. In the initial set of array analysis with U95 chips, GADD45 was identified to be a VD-induced gene in OVCAR3 cells, which was confirmed by a follow-up study to be a primary target gene. For the array analyses with U133A chips, the response to 1,25(OH)2D3 of the cells used for RNA isolation was ensured by Northern blotting analysis of GADD45. Three independent experiments were performed.