Project description:Characterizing the impact of pharmacological and shRNA-mediated silencing of EAG2 in medulloblastoma. Medulloblastoma (MB) is the most common pediatric CNS malignancy. Previously, we demonstrated that overexpression of the ion channel EAG2, identified in a subset of histological and molecular subtypes of this disease, functionally contributes to tumor progression (PMID: 22855790). Here, we demonstrate the evolutionarily conserved function of EAG2 potassium channel in promoting brain tumor growth and metastasis, delineate downstream pathways and uncover a co-option mechanism for different potassium channels to regulate mitotic cell volume and tumor progression. We show that EAG2 potassium channel is enriched at the trailing edge of migrating MB cells to regulate local cell volume dynamics, thereby facilitating cell motility. We identify the FDA- approved antipsychotic drug thioridazine as an EAG2 channel blocker that reduces xenografted MB growth and metastasis, and present a case report of repurposing thioridazine for treating a human patient. Our findings thus illustrate the potential of targeting ion channels in cancer treatment.
Project description:This project aimed to identify proteins copurifying with the Kv2.1 potassium channel from lysates prepared from crosslinked mouse brain homogenates. Comparison samples were prepared from Kv2.1 knockout mouse brains. Parallel immunopurifications were perfofmed for the unrelated Kv1.2 potassium channel.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Scaffold attachment factor B (SAFB) proteins are evolutionarily conserved DNA/RNA binding proteins that are involved in multiple processes of gene expression. These proteins are broadly expressed with particular high expression observed in the nervous system. However, their physiological roles in neurons are largely unclear. Here we show that PHM-2, the sole SAFB ortholog in C. elegans, regulates synaptic transmission at the neuromuscular junctions through an effect on SLO-2 potassium channel. We found that phm-2 knockout suppresses a sluggish phenotype of worms expressing a hyperactive SLO-2 channel, greatly reduces SLO-2-mediated neuronal whole-cell currents, and enhances neuromuscular synaptic transmission. In addition, we found that PHM-2 genetically interacts with another DNA/RNA binding protein, HRPU-2/hnRNP U, to control SLO-2 expression through a posttranscriptional mechanism. These results reveal a novel function of a SAFB protein in regulating neuronal activity, and may help understand the physiological roles of SAFB proteins in the nervous system of other species.
