Barbara A. Spengler

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Continuous cell lines, SK-N-SH and SK-N-MC, were established in cell culture from human metastatic neuro blastoma tissue and maintained in vitro for 1 to 2 years. SK-N-SH comprises two morphologically distinctive cell types, a small spiny cell and a large epithelioid cell. SKN-MC is composed of small fibroblast-like cells with scant cytoplasm. In monolayer(More)
This study was undertaken to determine whether the two type of cells (one neuroblast-like and the other epithelial in appearance) of the human neuroblastoma line SK-N-SH in culture undergo morphological interconversion, whether conversion is bidirectional, and whether there are coordinate neurochemical changes. Phenotypic analysis of serially isolated(More)
Previous studies of the human neuroblastoma cell line SK-N-SH had demonstrated the presence of and phenotypic interconversion (transdifferentiation) between two morphologically and biochemically distinct cell types: N (neuroblastic) cells with properties of noradrenergic neurons and S (substrate-adherent) cells with properties of melanocytes. Current(More)
Cellular heterogeneity is a hallmark of human neuroblastoma tumors and cell lines. Within a single neuroblastoma are cells from distinct neural crest lineages whose relative abundance is significant for prognosis. We postulate that a self-renewing multipotent tumor stem cell, which gives rise to diverse cell lineages, is the malignant progenitor of this(More)
Spontaneously transformed Chinese hamster lung cells with high levels of resistance (≈ 100-fold to 70,000-fold) to actinomycin D, daunorubicin, or vincristine exhibit morphology and growth patterns characteristic of normal cellsin vitro and reduced tumorigenicityin vivo. These reverse transformed, multidrug-resistant cells amplify and highly overexpress one(More)
Human neuroblastoma I-type cells isolated from cell lines in vitro are morphologically intermediate between neuroblastic (N) cells, with properties of embryonic sympathoblasts, and substrate-adherent (S) cells having properties of embryonic Schwann/glial/melanocytic cells of the neural crest. I cells have biochemical features of both N and S cells. We(More)
Large, homogeneously staining chromosome regions which lack the longitudinal differentiation ordinarily revealed by cytogenetic "banding" methods have been found in antifolate-resistant Chinese hamster cells and also in human neuroblastoma cells established in vitro. The drug-resistant cells are characterized by excessive production of the target enzyme,(More)
Herbal extracts of Hypericum perforatum L. (St. John's wort, SJW) are now successfully competing for status as a standard antidepressant therapy. Because of this, great effort has been devoted to identifying the antidepressive active compounds. In the present study we used the following strategy to evaluate the relative pharmacological importance of various(More)
Amplification of the N-myc proto-oncogene signifies aggressive behavior in human neuroblastoma. Likewise, overexpression of the intermediate filament nestin, a neuroectodermal stem cell marker, is linked to increased aggressiveness in several nervous system tumors. We investigated the interaction of these two proteins in human neuroblastoma cells.(More)
Human neuroblastoma is an embryonic cancer of the neural crest. Cellular heterogeneity is a characteristic feature of both tumors and derived cell lines. Recent studies have revealed that both cell lines and tumors contain cancer stem cells. In culture, these cells are self-renewing, multipotent, and highly malignant; in tumors their frequency correlates(More)