Since bone metastatic breast cancer is an incurable disease, causing significant morbidity and mortality, understanding of the underlying molecular mechanisms would be highly valuable. Here, we describe in vitro and in vivo evidence for the importance of serine biosynthesis in the metastasis of breast cancer to bone. We first characterized the bone metastatic propensity of the MDA-MB-231(SA) cell line variant as compared to the parental MDA-MB-231 cells by radiographic and histological observations in the inoculated mice. Genome-wide gene expression profiling of this isogenic cell line pair revealed that all the three genes involved in the L-serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH) were upregulated in the highly metastatic variant. This pathway is the primary endogenous source for L-serine in mammalian tissues. Consistently, we observed that the proliferation of MDA-MB-231(SA) cells in serine-free conditions was dependent on PSAT1 expression. In addition, we observed that L-serine is essential for the formation of bone resorbing human osteoclasts and may thus contribute to the vicious cycle of osteolytic bone metastasis. High expression of PHGDH and PSAT1 in primary breast cancer was significantly associated with decreased relapse-free and overall survival of patients and malignant phenotypic features of breast cancer. In conclusion, high expression of serine biosynthesis genes in metastatic breast cancer cells and the stimulating effect of L-serine on osteoclastogenesis and cancer cell proliferation indicate a functionally critical role for serine biosynthesis in bone metastatic breast cancer and thereby an opportunity for targeted therapeutic interventions.
Enhanced serine production by bone metastatic breast cancer cells stimulates osteoclastogenesis.
Specimen part, Cell lineView Samples
LYVE-1-positive macrophages were observed to be closely spatially associated with the developing lymphatic vasculature. The role of this population of macrophages in the embryo is uncharacterised.
Macrophages define dermal lymphatic vessel calibre during development by regulating lymphatic endothelial cell proliferation.
No sample metadata fieldsView Samples
RPB1, the largest subunit of RNA polymerase II, contains a highly modifiable C-terminal domain (CTD) that consists of variations of a consensus heptad repeat sequence (Y1S2P3T4S5P6S7). The consensus CTD repeat motif and tandem organization represent the ancestral state of eukaryotic RPB1, but across eukaryotes CTDs show considerable diversity in repeat organization and sequence content. These differences may reflect lineage-specific CTD functions mediated by protein interactions. Mammalian CTDs contain eight non-consensus repeats with a lysine in the seventh position (K7). Posttranslational acetylation of these sites was recently shown to be required for proper polymerase pausing and regulation of two growth factor-regulated genes. To investigate the origins and function of RPB1 CTD acetylation (acRPB1), we computationally reconstructed the evolution of the CTD repeat sequence across eukaryotes and analyzed the evolution and function of genes dysregulated when acRPB1 is disrupted. Modeling the evolutionary dynamics of CTD repeat count and sequence content across diverse eukaryotes revealed an expansion of the CTD in the ancestors of Metazoa. The new CTD repeats introduced the potential for acRPB1 due to the appearance of distal repeats with lysine at position seven. This was followed by a further increase in the number of lysine-containing repeats in developmentally complex clades like Deuterostomia. Mouse genes enriched for acRPB1 occupancy at their promoters and genes with significant expression changes when acRPB1 is disrupted are enriched for several functions, such as growth factor response, gene regulation, cellular adhesion, and vascular development. Genes occupied and regulated by acRPB1 show significant enrichment for evolutionary origins in the early history of eukaryotes through early vertebrates. Our combined functional and evolutionary analyses show that RPB1 CTD acetylation was possible in the early history of animals, and that the K7 content of the CTD expanded in specific developmentally complex metazoan lineages. The functional analysis of genes regulated by acRPB1 highlight functions involved in the origin of and diversification of complex Metazoa. This suggests that acRPB1 may have played a role in the success of animals.
Evolution of lysine acetylation in the RNA polymerase II C-terminal domain.
Cell lineView Samples
Whole blood RNA-seq was leveraged to explore gene expression changes induced in mice 24 hours after immunisation with a second dose of a licensed vaccine against capsular group B meningococcus, one of the vaccines components, or one of several comparator groups. Overall design: mRNA was profiled from RNA extracted from mouse whole blood, 5-6 samples per group, using an Illumina HiSeq4000
Comparative transcriptomics between species attributes reactogenicity pathways induced by the capsular group B meningococcal vaccine, 4CMenB, to the membrane-bound endotoxin of its outer membrane vesicle component.
Sex, Cell line, SubjectView Samples
Cystic Fibrosis lung disease progresses by a combination of accelerated airways inflammation and bacterial colonization and infection. Airways inflammation in CF is predominantly neutrophilic and complicates airway clearance therapies through cellular debris, excessive DNA, excessive and viscous mucous, and high concentrations of neutrophils,Il-8 and related cytokines liberated along the NFkB signaling pathway. We conducted a single site, randomized, double blind, placebo-controlled, proof-of-concept trial in which we evaluated the effects of 28 days of two dose levels (0.05 mg and 0.10 mg daily) of an older cardiac glycoside, digitoxin, as compared with placebo, on inflammatory markers in induced sputum obtained from 24 subjects with mild to moderate CF lung disease. Nasal epithelial cells from 23 subjects were analyzed for microarray analysis. CF patients 18 to 45 years old, any genotype combination, were eligible.
Digitoxin for Airway Inflammation in Cystic Fibrosis: Preliminary Assessment of Safety, Pharmacokinetics, and Dose Finding.
Specimen part, Disease, Disease stage, Treatment, Subject, TimeView Samples
We report the expression anaysis of neural stem cells lacking p53, ATMIN, or both. p53-deficent cells form GBM, which is significanly delayed in the absence of ATMIN.
Inactivation of the ATMIN/ATM pathway protects against glioblastoma formation.
Specimen partView Samples
We report differences in mRNA gene expression in rectal biopsies from MSM compared to controls and for MSM timed with episodes of CRAI. Overall design: Rectal biopsies were obtained from MSM at two study timepoints: 1. after who abstaining from CRAI for >72 hours and 2.after engaing in CRAI within the last 24 hours. Rectal biopsies were also obtained from men who never engaged in AI.
Short Communication: Anatomic Site of Sampling and the Rectal Mucosal Microbiota in HIV Negative Men Who Have Sex with Men Engaging in Condomless Receptive Anal Intercourse.
Specimen part, SubjectView Samples
The cerebral cortex underwent a rapid expansion and complexification during recent primate evolution, but the underlying developmental mechanisms remain essentially unknown.
Genes expressed in specific areas of the human fetal cerebral cortex display distinct patterns of evolution.
Age, Specimen partView Samples
Gliomas have been proposed to be driven by a population of neural stem-like cells. We isolated a panel of novel human glioma cell lines using adherent neural stem cell conditions.
Glioma stem cell lines expanded in adherent culture have tumor-specific phenotypes and are suitable for chemical and genetic screens.
Specimen partView Samples
CD11c+ Myeloid Dendritic Cells (mDCs) were isolated from the peripheral blood mononuclear cells (PBMCs) of HIV uninfected and HIV infected subjects.
Chronic HIV infection enhances the responsiveness of antigen presenting cells to commensal Lactobacillus.
Age, Specimen partView Samples