title: Proliferation of hematopoietic cell lines induced by a soluble factor derived from human squamous cell carcinomas of the head and neck.
abstract: The supernatant of a cell line of squamous cell carcinoma of the head and neck (SCCHN), PCI-50, was previously shown to induce activation, promote proliferation and increase antitumor cytotoxicity of freshly purified human natural killer (NK) cells and CD4+ T lymphocytes [Arch Otolaryngol Head Neck Surg (1994) in press]. This supernatant was found also to promote the growth of a variety of hematopoietic cell lines, including Jurkat, THP-1, K562, NK-92 or Epstein-Barr-virus-transformed B cell lines. The Jurkat cell line was selected as a reporter cell in an 18-h proliferation assay established to measure the growth-promoting activity of PCI-50 supernatant. The presence of soluble tumor-derived factors able to induce proliferation of Jurkat cells was demonstrated in the supernatant produced by several other SCCHN cell lines but not in that produced by a gastric cancer cell line (HR) or renal cell carcinoma line (5117G8). The growth-promoting PCI-50 supernatant was shown to contain 28 +/- 0.5 pg/ml interleukin-6 (IL-6) in vitro but was negative for interferon gamma, IL-1, IL-2, IL-4, tumor necrosis factor alpha, granulocyte/macrophage-colony-stimulating factor and IL-12. The addition of any of these recombinant cytokines to Jurkat cell cultures did not significantly promote growth, while PCI-50 supernatant was consistently growth-stimulatory. This supernatant neither enhanced intracellular Ca2+ concentration in Jurkat cells nor induced up-regulation of activation antigens on the cell surface, although it supported growth of Jurkat cells in the absence of IL-2. The growth-promoting activity in the PCI-50 supernatant was acid-labile at pH 2 for 4 h, heat-resistant at 96 degrees C for 1 h and sensitive to treatments with trypsin and pepsin. Preincubation of the PCI-50 producer cells with tunicamycin or cyclohexamide reduced the level of growth-promoting activity in the supernatant. A partial purification of this activity was achieved using Amicon filtration, chromatography on concanavalin-A-Sepharose and then a hydroxyapatite column and high-pressure liquid chromatography gel filtration. The partially purified glycoprotein had a molecular mass of 50-70 kDa, as determined by gel filtration.
authors.affiliation: Department of Pathology, University of Pittsburgh School of Medicine, PA.
authors.forename: S
authors.initials: S
authors.lastname: Yasumura
authors.forename: A
authors.initials: A
authors.lastname: Amoscato
authors.forename: H
authors.initials: H
authors.lastname: Hirabayashi
authors.forename: W C
authors.initials: WC
authors.lastname: Lin
authors.forename: T L
authors.initials: TL
authors.lastname: Whiteside
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D016207:Cytokines / Q000494:pharmacology; D006133:Growth Substances / Q000302:isolation & purification / Q000494:pharmacology*; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects; D009000:Monocytes / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D016207:Cytokines; D006133:Growth Substances; D011994:Recombinant Proteins