title: Mortality of human epidermal keratinocytes in co-culture with oral squamous cell carcinoma cells.
abstract: Normal human epidermal keratinocytes (NHEK) died after 5 days of co-culture with an oral carcinoma cell line (HSC-4). However, the HSC-4 cells did not change in either mitotic character or shape. We analyzed the changes in the mitotic activity and DNA synthetic activity of NHEK in co-culture with the HSC-4 cells. The mitotic index of the NHEK decreased gradually with the presence of human beta-defensin-2 (HBD-2) in the media. However, the mitotic index (MI) of the HSC-4 cells did not change. The shape of the NHEK cells did not change during co-culture. The time changes of the labeling index (LI) measured by BrdU incorporation, and the LI decreased in neither NHEK nor in HSC-4 cells in the presence of HBD-2. Moreover, in co-culture with an anti-HBD-2 antibody, the MI of both NHEK and HSC-4 cells did not change. These results indicate that HBD-2 might not lead to apoptosis or necrosis, but rather to cellular reproductive death in NHEK cells. However, HSC-4 cells might be more tolerant of HBD-2, so that HBD-2 does not cause cellular reproductive death. HBD-2 does not diminish the DNA synthesis rate but decreases the mitotic activity in NHEK cells in vitro. HBD-2 diminishes neither the DNA synthesis rate nor the mitotic activity in HSC-4 cells.
authors.affiliation: Department of Oral and Maxillofacial Reconstructive Surgery, Okayama University Dental School, 2-5-1 Shikata-cho, Okayama 700-8525, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Sawaki
authors.forename: Tomoichiro
authors.initials: T
authors.lastname: Yamaai
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Mizukawa
authors.forename: Tomohitio
authors.initials: T
authors.lastname: Yoshimoto
authors.forename: Takaaki
authors.initials: T
authors.lastname: Ueno
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakano
authors.forename: Toshio
authors.initials: T
authors.lastname: Sugahara
mesh_terms: D001973:Bromodeoxyuridine / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D002450:Cell Communication / Q000187:drug effects / Q000502:physiology*; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D018920:Coculture Techniques; D017077:Culture Media, Conditioned; D000078404:Epidermal Cells; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000187:drug effects; D008938:Mitosis / Q000187:drug effects / Q000502:physiology; D009062:Mouth Neoplasms / Q000473:pathology*; D014407:Tumor Cells, Cultured; D023083:beta-Defensins / Q000494:pharmacology* / Q000502:physiology
chemical_list: D017077:Culture Media, Conditioned; C106641:DEFB4A protein, human; D023083:beta-Defensins; D001973:Bromodeoxyuridine