MYCN and neuroblastoma: To evaluate whether upregulation of Fas and PVR mediated by the transient increased expression of the NF-kB p65 subunit could affect the susceptibility of high-risk NB cell lines to NK-cell-mediated recognition and killing, MYCN non-amplified SH-SY-5Y and ACN cell lines and MYCN-amplified LA-N-5 and SMS-KCNR NB cells were transfected with the gene encoding for p65 and used as targets in NK-cell-mediated apoptosis, degranulation, and cytotoxicity assays.