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Establishment and characterization of a human neuroblastoma cell line

A continuous human cell line RN‐GA was established from a stage‐III primary neuroblastoma prior to therapy. Light and electron microscopic analysis of the biopsy showed morphological features typical of neuroectodermal origin. Relative cellular DNA content and N‐myc oncogene copy number were also analyzed in the biopsy tissue: the tumor cells presented a near‐diploid genome with N‐myc amplification. The derived tumor cell line expressed distinctive ultrastructural, cytogenetic and immunological markers of neuroblastoma. Moreover, cells from the culture could be serially transplanted into splenectomized‐irradiated nude mice, where they formed a progressively growing solid tumor. Surprisingly, the cells in culture did not show any N‐myc amplification, while they retained a near‐diploid DNA content. We propose that several techniques (electron microscopy, oncogene analysis, flow cytometry, cytogenetics, tissue culture, cell antigen immunodetection) should be used to establish a firm diagnosis and a correct clinical grading of this tumor. The establishment of this continuous cell line should be valuable as an experimental in vitro system for further studies of neuroblastoma biology and morphology.