SOCS3 and cancer: Because a direct neuroblastoma–immune cell interaction would be facilitated by either proteins secreted or expressed on the cancer cell surface, we selected TNFRSF4, TNFRSF1B, GNLY and SOCS3 for validation of expression trends via RT‒qPCR in fresh-frozen cisplatin-sensitive and resistant metastatic tissue matched to the FFPE tissue used in RNA-seq.