Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer fatalities in Western societies, characterized by high metastatic potential and resistance to chemotherapy. Critical molecular mechanisms of these phenotypical features still remain unknown, thus hampering the development of effective prognostic and therapeutic measures in PDAC. Here we show that transcriptional co-factor Transducin beta-like (TBL) 1 was over-expressed in both human and murine PDAC. Inactivation of TBL1 in human and mouse pancreatic cancer cells reduced cellular proliferation and enhanced chemosensitivity, correlating with diminished glucose uptake, glycolytic flux, and PI3kinase signaling. TBL1 deficiency both prevented and reversed pancreatic tumor growth in mice, triggering transcriptional PI3kinase inhibition also in vivo. As TBL1 mRNA levels were also found to correlate with overall and disease-free survival in a cohort of human PDAC patients and to predict therapy responsiveness in these subjects, TBL1 expression may serve both as a novel prognostic marker and molecular target in the treatment of human PDAC.
Transcriptional co-factor Transducin beta-like (TBL) 1 acts as a checkpoint in pancreatic cancer malignancy.
Cell line, TreatmentView Samples
Data on the temporal dynamics of human placental gene expression is scarce. We have completed the first whole-genome profiling of human placental gene expression dynamics (GeneChips, Affymetrix) from early to mid- gestation (10 samples; gestational weeks 5 to 18) and report 154 genes with considerable change in transcript levels (FDR P<0.1). Functional enrichment analysis revealed >200 GO categories that are statistically over-represented among 105 genes with dynamically increasing transcript levels. Analysis in an extended sample (n=43; gestational weeks 5 to 41) conformed a highly significant (FDR P<0.05) expressional peak in mid-gestation placenta for ten genes: BMP5, CCNG2, CDH11, FST, GATM, GPR183, ITGBL1, PLAGL1, SLC16A10, STC1. A central hypothesis of our study states that the aberrant expression of genes characteristic to mid-gestation placenta may contribute to affected fetal growth, maternal preeclampsia (PE) or gestational diabetes (GD). The gene STC1 coding for Stanniocalcin 1 (STC1) was identified with a sharp placental expressional peak in mid-gestation, increased mRNA levels at term and significantly elevated STC1 protein levels in post-partum maternal plasma in all pregnancy complications. The highest STC1 levels were identified in women, who developed simultaneously PE and delivered an SGA baby (median 731 vs 418 pg/ml in controls; P=0.001). CCNG2 and LYPD6 exhibited significantly increased placental mRNA expression and enhanced intensity of immunohistochemistry staining in placental sections all studied in GD and PE cases. Aberrant expression of mid-gestation specific genes in pregnancy complications at term indicates the importance of the fine-scale tuning of the temporal dynamics of transcription regulation in placenta. Observed significantly elevated plasma STC1 in complicated pregnancies warrants further investigations of its potential as a biomarker. Interestingly, a majority of genes with high expression in mid-gestation placenta have also been implicated in adult complex disease. This observation promotes a recently opened discussion on the role of placenta in developmental programming.
Mid-gestational gene expression profile in placenta and link to pregnancy complications.
Specimen partView Samples
Here we show that in neural progenitor cells (NPCs) TRIM28 silences transcription of two groups of endogenous retroviruses (ERVs): IAP1 and MMERVK10C. Derepression of ERVs in Trim28-deficient NPCs was associated with a loss of H3K9me3 and resulted in transcriptional upregulation and reverse transcription. These findings demonstrate a unique dynamic transcriptional regulation of ERVs in NPCs. Overall design: Analysis of upregulation of ERVs in Trim28-deficient NPCs
TRIM28 represses transcription of endogenous retroviruses in neural progenitor cells.
Specimen part, Cell line, SubjectView Samples
The 600kb BP4-BP5 16p11.2 CNV (copy number variant) is associated with neuroanatomical, neurocognitive and metabolic disorders. These recurrent rearrangements are associated with reciprocal phenotypes such as obesity and underweight, macro- and microcephaly, as well as autism spectrum disorder (ASD) and schizophrenia. Here we interrogated the transcriptome of individuals carrying reciprocal CNVs in 16p11.2.
A Potential Contributory Role for Ciliary Dysfunction in the 16p11.2 600 kb BP4-BP5 Pathology.
Sex, Age, Specimen partView Samples
Not all patients with nerve injury develop neuropathic pain. The extent of nerve damage and age at the time of injury are two of the few risk factors identified to date. In addition, preclinical studies show that neuropathic pain variance is heritable. To define such factors further, we performed a large-scale gene profiling experiment which plotted global expression changes in the rat dorsal root ganglion in three peripheral neuropathic pain models. This resulted in the discovery that the potassium channel alpha subunit KCNS1, involved in neuronal excitability, is constitutively expressed in sensory neurons and markedly downregulated following nerve injury. KCNS1 was then characterized by an unbiased network analysis as a putative pain gene, a result confirmed by single nucleotide polymorphism association studies in humans. A common amino acid changing allele, the 'valine risk allele', was significantly associated with higher pain scores in five of six independent patient cohorts assayed (total of 1359 subjects). Risk allele prevalence is high, with 18-22% of the population homozygous, and an additional 50% heterozygous. At lower levels of nerve damage (lumbar back pain with disc herniation) association with greater pain outcome in homozygote patients is P = 0.003, increasing to P = 0.0001 for higher levels of nerve injury (limb amputation). The combined P-value for pain association in all six cohorts tested is 1.14 E-08. The risk profile of this marker is additive: two copies confer the most, one intermediate and none the least risk. Relative degrees of enhanced risk vary between cohorts, but for patients with lumbar back pain, they range between 2- and 3-fold. Although work still remains to define the potential role of this protein in the pathogenic process, here we present the KCNS1 allele rs734784 as one of the first prognostic indicators of chronic pain risk. Screening for this allele could help define those individuals prone to a transition to persistent pain, and thus requiring therapeutic strategies or lifestyle changes that minimize nerve injury.
Multiple chronic pain states are associated with a common amino acid-changing allele in KCNS1.
Myeloid Angiogenic Cells (MACs) were infected with the intracellular, bacterial pathogen Bartonella henselae (B.h.). Infected cells were seeded onto Matrigel coated plates. While uninfected cells showed no phenotypic changes and died over time, infected cells showed strong phenotypic changes and developed into complex 2D chord networks over the course of long term culture (eg 49d). To examine the changes in gene expression associated with the development of the B.h.dependent chord formation phenotype, RNA was isolated from MACs shortly after isolation (d4) and from cells of the chord structures (+B.h. Matrigel). As primary endothelial cells are also know to form chord networks when cultured on Matrigel, a sample of human umbilical vein endothelial cells (HUVECs) cultured on Matrigel for 12hr was also included in the analysis as a control.
Reprogramming of myeloid angiogenic cells by Bartonella henselae leads to microenvironmental regulation of pathological angiogenesis.
Specimen part, Subject, TimeView Samples
We report a highly-penetrant form of obesity, initially observed in 31 heterozygous carriers of a 593kb or larger deletion at 16p11.2 from amongst subjects ascertained for cognitive deficits. Nineteen similar deletions were identified from GWAS data in 16053 individuals from 8 European cohorts; such deletions was absent from healthy non-obese controls and accounted for 0.7% of our morbid obesity cases (p = 6.4x10-8, OR = 43). These findings highlight a promising strategy for identifying missing heritability in obesity and other complex traits, in which insights from rare extreme cases can be used to elucidate the basis for more common phenotypes.
A new highly penetrant form of obesity due to deletions on chromosome 16p11.2.
Specimen part, DiseaseView Samples