Abstract
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.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 2056-2074 |
| Number of pages | 19 |
| Journal | Epigenetics |
| Volume | 17 |
| Issue number | 13 |
| DOIs | |
| State | Published - 2022 |
Funding
This work was supported by Alex’s Lemonade Stand and a Northwestern Mutual Young Investigator Grant. A.E.H. was supported by The Molecular and Cellular Biology Training Grant, and the HHMI Med-into-Grad Translational Training Program. M.A.A. was supported by the National Institutes of Health, K08CA226237. We thank Dr. Paul Geeleher for performing statistical analysis of wound-healing assay data sets. We would also like to thank Dr. Marsha Rosner and Dr. Chilong Nguyen for their invaluable instruction of several protein biochemistry techniques. Finally, we would like to thank Dr. Julie Losman for her CRISPR plasmids targeting HIF1A.
Keywords
- MYCN
- TET1
- hypoxia
- neuroblastoma
ASJC Scopus subject areas
- Molecular Biology
- Cancer Research
