Project description:Glioblastoma is the most common primary brain cancer and is associated with poor survival and high rates of recurrent diseases. The median survival using standard radio-chemotherapy is 15 months and the 5-year survival rate is below 5%. It is hypothesized that treatment resistance, diffuse infiltration of the brain and disease recurrence is, at least in part, due to cancer cells that can obtain a transient, stem-like phenotype. These so-called glioma stem-like cells (GSCs) display pluripotency, express marker proteins associated with stem-cells and can replenish the tumor after treatment. Recently, we have shown that the hormonally active form of vitamin D3, calcitriol (1α,25(OH)2-vitamin D3), is active in a subset of GSCs and reduces traits of stemness. Here, we have employed a set of 8 GSCs that do not respond to calcitriol-treatment (No-responder) and the 8 strongest responders to calcitriol (High-responder) and compared to proteomes after treatment with 50 nM calcitriol for 48h.
Project description:Using pangenomic cDNA microarrays and qPCR techniques, we identified the genes regulated by calcitriol (1,25 (OH)D3, 10 nM) in dorsal root ganglia and/or Schwann cells. After 24 hours of calcitriol supplementation, we found a modified expression of many genes involved in axogenesis and myelination.
Project description:Effects of calcitriol on expressions of ER stress related genes were evaluated with microarray. Calcitriol, the active form of vitamin D, is known to induce apoptosis in cancer cells and increase intracellular calcium. Increase in cytopalsmic calcicium levels may indicate a decrease in endoplasmic reticulum (ER) calcium levels since ER is the main storage unit for calcium. Decrease in ER calcium levels are known to induce ER stress which can lead to apoptosis. However the effects of calcitriol on ER stress have not been reported before. Here we hypotesized that the cellular effects of calcitriol can be explained by induction of ER stress. We have tested this hypothesis by assessing calcitriol induced transcriptomic alterations with a focus on ER stress related genes.
Project description:We aimed to explore the potential and mechanism of calcipotriol to regulate the hepatocellular transcriptome in comparison to calcitriol.
Project description:The mechanism of action of vitamin D in prostate cancer (PCa) remains poorly defined, with most mechanisms identified being highly cell type and model specific. One of the underlying factors for these diverse mechanisms may be the use of overly simplistic in vitro model systems to study the complex biology of vitamin D response. Here we use the more complex and in vivo transgenic adenocarcinoma of mouse prostate (TRAMP) model to better determine the mechanism by which vitamin D inhibits PCa growth. In these studies early stage TRAMP mice were treated M-BM-1 20M-NM-<g/kg calcitriol (vitamin D) on a Monday/Wednesday/Friday schedule and tissue was procured 12 and 24 hours post treatment to assess changes in PCa transcriptomes using Affymetrix gene expression arrays. 15 total samples were analyzed. 10 week old TRAMP mice were treated IP M-BM-1 20 ug/kg calcitriol on a Monday/Wednesday/Friday (MWF) schedule, and prostate tissue was procured 12 (N=3, control; N=4, calcitriol) and 24 hours (N=4, control; N=4, calcitriol) post treatment for use in affymetrix studies.
Project description:We analyzed anterior halves of NF stage 15 embryos that were treated with 10uM DMSO (control), or 1uM RA and 10uM 4-oxo-RA (experimental) for changes in gene expression induced by the two mophogens. RNA-sequencing revealed significant overlap in genes upregulated by both RA and 4-oxo-RA, and to a lesser extent, those downregulated by them. We report all Zic-1 targets described in accompanying manuscript to be regulated by both RA and 4-oxo-RA.
Project description:Purpose: It has been proposed that vitamin D may play a role in prevention and treatment of cancer while epidemiological studies have linked vitamin D insufficiency to adverse disease outcome in chronic lymphocytic leukemia (CLL). However, the underlying mechanisms have not yet been revealed. In this study, we sought to identify key signaling pathways and molecules that are altered after calcitriol, the biologically active form of vitamin D, supplementation of CLL cells in vitro. Methods: An RNA-Sequencing analysis was performed in primary CLL cells that were treated in vitro with calcitriol. Total RNA was extracted from calcitriol-treated and non-treated CLL cells, while mRNA selection was performed using NEBNext Poly(A) mRNA Magnetic Isolation Module. Library preparation for RNA-Sequencing (RNA-Seq) analysis was conducted with the NEBNext Ultra II Directional RNA Library Prep Kit. The libraries were paired-end sequenced on the NextSeq 500 Illumina platform. Differential expression analysis was performed using DESeq2; genes with log2FC>|1| and P≤0.05 were considered as differentially expressed. Results: Differential expression analysis revealed 85 differentially expressed genes (DEGs) (log2FC≥|1| and p≤0.05), of which 28 (32.9%) were overexpressed in calcitriol-treated cells versus unstimulated CLL cells, thus, contrasting the remaining 57 (67.1%) which showed the opposite pattern. Supervised hierarchical clustering analysis, based on the differentially expressed genes, was performed and revealed distinct gene expression patterns between calcitriol-treated and control CLL cells. Moreover, pathway enrichment analysis revealed that calcitriol-regulated genes are implicated in signaling pathways known to be deregulated in CLL biology. Conclusions: Transcriptome analysis highlighted the possible impact of calcitriol on the regulation of immune signaling pathways relevant to CLL pathophysiology.
Project description:Cancer cells with a stem-like phenotype are commonly described in glioblastoma, the most common primary adult brain cancer, that are thought to be highly tumorigenic. This phenotype comprimes high self renewal capacity and resistance against chemotherapy and radiation therapy, thereby promoting tumor progression and disease relapse. Here we show for the first time that calcitriol, the hormonally active form of the “sun hormone” vitamin D3, effectively suppresses stemness properties in glioblastoma stem-like cells (GSCs), supporting the hypothesis that cal-citriol sensitizes them to additional chemotherapy. Indeed, a physiologically relevant organotypic brain slice model was used to monitor tumor growth of GSCs and the effectiveness of combined treatment with temozolomide, the current standard-of-care, and calcitriol was proven. These findings indicate that further research on applying calcitriol, a well known and safe drug, as a potential adjuvant therapy for glioblastoma is both justified and necessary.