Project description:Hypertrophic cardiomyopathy (HCM) caused by autosomal-dominant mutations in genes that code for the structural proteins of the sarcomere, is the most common inherited heart disease. HCM is associated with progressive myocardial hypertrophy and fibrosis, ventricular dysfunction, and arrhythmias. Disease onset during childhood and adolescence carries the risk of morbidity and sudden cardiac death. Hypoxia and the main regulator of the cellular hypoxic response hypoxia-inducible transcription factor-1a (HIF1A) have been associated with HCM, however their exact roles are not elucidated yet.
Project description:Solid tumors such as breast cancer have intratumoral regions of low oxygen tension, which influence a vast array of cellular responses. Hypoxia-Inducible Factor 1-alpha (HIF1α) represents the principal transcription factor orchestrating cellular responses to hypoxic conditions, mediating the regulation of genes implicated in oxygen homeostasis. The nucleolus is central stress response hub in the cell, as such we sought to identify novel binding partners of HIF1α in the nucleolar compartment during hypoxic stress.
Project description:This is a mathematical model comprised of non-linear ordinary differential equations describing the dynamic relationship between hypoxia-inducible factor-1 alpha (HIF-1a) mRNA, HIF-1a protein, and interleukin-15-mediated upstream signalling events in natural killer cells from human blood. Regulatory expressions are also included for mammalian target of rapamycin (mTOR), nuclear factor-kappa beta, and signal transducer and activator of transcription 3 (STAT3).
Project description:Clioquinol (CQ) has been identified as a hypoxic mimicker to activate hypoxia-inducible factor-1α (HIF-1α) by inhibiting HIF-1a specific asparaginyl hypoxylase (Factor inhibiting HIF-1, FIH-1). We previously showed that hypoxia coordinately regulate induction or repression of hypoxia-responsive genes by altering different types of methylations (H3K4me3, H3K9me3, and H3K27me3) at gene level. Here, we investigated CQ-mediated regulation of the expression of hypoxia-responsive genes and whether CQ had a similar effect on histone methylation and transcription of target genes under hypoxia.
Project description:Differential expression of the oxygen sensitive hypoxia-inducible transcription factor (HIF) subunits HIF-1a and HIF-2a occurs in many tumor types, but the underlying regulatory mechanisms remain poorly understood. Here we investigate the role of mTOR complex in the regulation of HIF expression in cells cultured under hypoxic conditions.
Project description:Clioquinol (CQ) has been identified as a hypoxic mimicker to activate hypoxia-inducible factor-1α (HIF-1α) by inhibiting HIF-1a specific asparaginyl hypoxylase (Factor inhibiting HIF-1, FIH-1). We previously showed that hypoxia coordinately regulate induction or repression of hypoxia-responsive genes by altering different types of methylations (H3K4me3, H3K9me3, and H3K27me3) at gene level. Here, we investigated CQ-mediated regulation of the three histone methylations and whether CQ had a similar effect on histone methylation and transcription of target genes under hypoxia.
Project description:Differential expression of the oxygen sensitive hypoxia-inducible transcription factor (HIF) subunits HIF-1a and HIF-2a occurs in many tumor types, but the underlying regulatory mechanisms remain poorly understood. Here we investigate the role of mTOR complex in the regulation of HIF expression in cells cultured under hypoxic conditions. Neuroblastoma SK-N-BE(2)c cells were treated with DMSO or the mTORC complex inhibitor PP242 and cultured at hypoxia for 24, 48 or 72 hours.
Project description:HIF-1 (Hypoxia-inducible factor 1) is the master regulator responding to hypoxic conditions. Here, we found that HIF-1A is citrullinated by peptidyl arginine deiminase 4 (PADI4) at arginine 698, promoting HIF-1A stabilization and thus HIF-1-driven tumor growth. The knockdown of PADI4 could dramatically decrease HIF-1 protein expression without affecting the mRNA level, and this could be rescued by the proteasome inhibitor MG132 treatment under hypoxia. And PADI4-HIF-1A interaction is critical for HIF-1A stability and tumor progression, depending on the enzymatic activity of PADI4 and the pocket structure of PADI4. DHE, an FDA-approved agent for the treatment of migraine, was found serve as a potential antitumor agent throgh disrupting PADI4-HIF-1A interaction and suppressing HIF-1A stability. Taken together, we found the anti-tumor effect of DHE due to its effect on blocking PADI4-HIF-1A interaction and downregulating HIF-1A pathway in cancer cells. To figure out the influence of DHE on liver cancer cell under hypoxia, we treated Hep3B cell lines with two does DHE in 6 hours under Hypoxia and extracted mRNA for furthur RNA seq.
Project description:This study compared 9 human islet preparations, extracted and prepared for clinical transplantation. Human islets were isolated as, and all were of transplant quality. Unamplified RNA was extracted and hybridized to Affymetrix HGU133+2 arrays. By using gene set enrichment analysis to investigate the variability of each probeset on the array, it was clear that isolated human islets undergo varying degrees of hypoxic stress. Further to this, key glycolytic genes, all of which are under the control of hypoxia inducing factor 1a (HIF-1a) were activated, indicating a switch towards anareobic glycolysis. Glycolysis severely impairs the ability of islets to sense glucose and secrete insulin in response to elevated blood sugar. We confirmed these findings in mouse rodents, demonstrated a dependance upon HIF-1a, and showed that even after 4 weeks, hypoxic islets retained their glycolytic molecular profile.
