FOXD3 and neuroblastoma: Co-immunoprecipitation (co-IP) was then performed to identify which PARP1-interacting protein was the target of FOXD3-AS1, and the results show that FOXD3-AS1 represses the PARP1-mediated PARylation of CCCTC-binding factor (CTCF) which plays an oncogenic role in NB.