title: The side population, as a precursor of Hodgkin and Reed-Sternberg cells and a target for nuclear factor-κB inhibitors in Hodgkin's lymphoma.
abstract: Although disturbed cytokinesis of mononuclear Hodgkin (H) cells is thought to generate Reed-Sternberg (RS) cells, differentiation of Hodgkin's lymphoma (HL) cells is not fully understood. Recent studies indicate that cells found in a side population (SP) share characteristics of cancer stem cells. In this study we identified an SP in the HL cell lines, KMH2 and L428. This SP almost entirely consists of distinct small mononuclear cells, whereas the non-SP is a mixture of relatively large cells with H or RS cell-like morphology. Culture of the small mononuclear cells in the SP from KMH2 generated a non-SP. Single cell culture of the SP cells generated large cells with H or RS cell-like morphology. We found that CD30 overexpression and constitutive nuclear factor-κB (NF-κB) activity, both of which are characteristics of HL cells, are shared between the SP and non-SP cells for both KMH2 and L428. Inhibition of NF-κB induced apoptosis in both fractions, whereas the SP cells were resistant to a conventional chemotherapeutic agent doxorubicin. The results show that HL cell lines contain an SP, that is enriched for distinct small mononuclear cells and generates larger cells with H and RS cell-like morphology. The results also stress the significance of NF-κB inhibition for eradication of HL cells.
authors.affiliation: Department of Hematology, School of Medicine, Kitasato University, Minami-ku, Sagamihara, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakashima
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Ishii
authors.forename: Mariko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Tomiteru
authors.initials: T
authors.lastname: Togano
authors.forename: Kazuo
authors.initials: K
authors.lastname: Umezawa
authors.forename: Masaaki
authors.initials: M
authors.lastname: Higashihara
authors.forename: Toshiki
authors.initials: T
authors.lastname: Watanabe
authors.forename: Ryouichi
authors.initials: R
authors.lastname: Horie
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001549:Benzamides / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003512:Cyclohexanones / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D004351:Drug Resistance; D005434:Flow Cytometry; D015726:Giant Cells / Q000378:metabolism / Q000473:pathology; D006689:Hodgkin Disease / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D017730:Ki-1 Antigen / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000378:metabolism / Q000473:pathology; D008856:Microscopy, Fluorescence; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000473:pathology; D016539:Reed-Sternberg Cells / Q000378:metabolism* / Q000473:pathology
chemical_list: D000903:Antibiotics, Antineoplastic; D001549:Benzamides; D003512:Cyclohexanones; D017730:Ki-1 Antigen; D016328:NF-kappa B; C464444:dehydroxymethylepoxyquinomicin; D004317:Doxorubicin