MYCN and HIF-1 directly regulate TET1 expression to control 5-hmC gains and enhance neuroblastoma cell migration in hypoxia

Autor: Hains, Anastasia E., Uppal, Sakshi, Cao, John Z., Salwen, Helen R., Applebaum, Mark A., Cohn, Susan L., Godley, Lucy A.
Rok vydání: 2022
Předmět:
Zdroj: Epigenetics. 17:2056-2074
ISSN: 1559-2308
1559-2294
DOI: 10.1080/15592294.2022.2106078
Popis: Ten-Eleven-Translocation 5-methylcytosine dioxygenases 1–3 (TET1-3) convert 5-methylcytosine to 5-hydroxymethylcytosine (5-hmC), using oxygen as a co-substrate. Contrary to expectations, hypoxia induces 5-hmC gains in MYCN-amplified neuroblastoma (NB) cells via upregulation of TET1. Here, we show that MYCN directly controls TET1 expression in normoxia, and in hypoxia, HIF-1 augments TET1 expression and TET1 protein stability. Through gene-editing, we identify two MYCN and HIF-1 binding sites within TET1 that regulate gene expression. Bioinformatic analyses of 5-hmC distribution and RNA-sequencing data from hypoxic cells implicate hypoxia-regulated genes important for cell migration, including CXCR4. We show that hypoxic cells lacking the two MYCN/HIF-1 binding sites within TET1 migrate slower than controls. Treatment of MYCN-amplified NB cells with a CXCR4 antagonist results in slower migration under hypoxic conditions, suggesting that inclusion of a CXCR4 antagonist into NB treatment regimens could be beneficial for children with MYCN-amplified NBs. In MYCN-amplified neuroblastoma cell lines, MYCN directly controls TET1 expression in normoxia.In MYCN-amplified neuroblastoma cell lines exposed to hypoxia, HIF-1 augments TET1 expression and TET1 protein stability.Hypoxic MYCN-amplified neuroblastoma cell lines have increased cell migration, mediated by genes including CXCR4 that gain 5-hydroxymethylcytosine density.Treatment of MYCN-amplified NB cells with a CXCR4 antagonist slows hypoxia-associated migration, suggesting a CXCR4 antagonist could be beneficial in treatment regimens for children with MYCN-amplified neuroblastomas. In MYCN-amplified neuroblastoma cell lines, MYCN directly controls TET1 expression in normoxia. In MYCN-amplified neuroblastoma cell lines exposed to hypoxia, HIF-1 augments TET1 expression and TET1 protein stability. Hypoxic MYCN-amplified neuroblastoma cell lines have increased cell migration, mediated by genes including CXCR4 that gain 5-hydroxymethylcytosine density. Treatment of MYCN-amplified NB cells with a CXCR4 antagonist slows hypoxia-associated migration, suggesting a CXCR4 antagonist could be beneficial in treatment regimens for children with MYCN-amplified neuroblastomas.
Databáze: OpenAIRE