S-CELLS FROM A HIGHLY N-MYC-AMPLIFIED NEUROBLASTOMA ARE TUMORIGENIC IN NUDE-MICE

Some neuroblastoma tumors when cultured in vitro give rise to N (neuro nal) and S (non-neuronal) cells, which differ in morphology, state of differentiation, and tumorigenicity. Previously, tumor-forming potenti al was shown to be characteristic of N cells but not S cells. We exami ned cutlures of N and S cells derived from a well-characterized, N-myc -amplified human neuroblastoma cell line, NBL-W, to determine whether these N and S cells also show differential tumorigenicity in nude mice . N cells formed tumors in 94% of trials and S cells formed tumors in 56% of trials. Although S cell tumors had a longer lag phase prior to tumor development, when turners developed, both N and S cell-derived t umors grew rapidly. These results suggest that S cells do not always r epresent a benign component of neuroblastomas.