title: Tobacco smoke-induced immunologic changes may contribute to oral carcinogenesis.
abstract: OBJECTIVE
  The objective of this study was to determine if tobacco smoke (TS), a risk factor for cancers of the aerodigestive tract, may contribute to oral carcinogenesis, in part, by suppressing local immunity.
  
  
  METHODS
  Mice were placed in Plexiglas holders in which they breathed TS through the nose and mouth for 1 hour daily for 21 days. Control mice breathed room air in the same manner. One day after the last exposure, mice were immunized by application of oxazolone to each buccal mucosa. Control mice were mock immunized by application of vehicle alone. Five days later, all mice were challenged on the ears with oxazolone, and 24-hour ear swelling assessed as contact hypersensitivity.
  
  
  RESULTS
  Mice exposed to TS had a significantly smaller contact hypersensitivity response compared with controls. When subsequently reimmunized on the glabrous skin, mice originally primed through TS-exposed mucosa could not be fully immunized, indicating induction of immunologic tolerance by exposure to hapten through TS-perturbed mucosa. Immunocompetent mice exposed to TS in this manner and challenged by submucosal placement of a syngeneic malignant tumor had significantly increased tumor growth over time compared with controls. No difference in growth rate was observed when the experiment was performed with natural killer cell-deficient, SCID (severe combined immunodeficiency) mice. In addition, exposure of epidermal Langerhans cells in vitro to an aqueous extract of TS impaired their ability to undergo maturation and to present antigen to responsive T cells.
  
  
  CONCLUSIONS
  Immunologic changes induced in the oral cavity by exposure to TS may play a role in the development of oral cancers.
authors: From the Departments of *Dermatology and †Medicine, Weill Cornell Medical College, New York, NY ‡Department of Surgery (Head and Neck Service), Memorial Sloan-Kettering Cancer Center, New York, NY; §Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins Medical Institutions, Baltimore, MD; and ∥Department of Public Health, Weill Cornell Medical College, New York, NY.
authors: Michael
authors: M
authors: Schierl
authors: Daxesh
authors: D
authors: Patel
authors: Wanhong
authors: W
authors: Ding
authors: Amit
authors: A
authors: Kochhar
authors: Katayun
authors: K
authors: Adhami
authors: Xi Kathy
authors: XK
authors: Zhou
authors: Andrew J
authors: AJ
authors: Dannenberg
authors: Richard D
authors: RD
authors: Granstein
mesh_terms: D000818:Animals; D005260:Female; D007108:Immune Tolerance / Q000276:immunology*; D019570:Inhalation Exposure / Q000009:adverse effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008822:Mice, Transgenic; D009062:Mouth Neoplasms / Q000209:etiology* / Q000276:immunology* / Q000473:pathology; D012907:Smoking / Q000009:adverse effects* / Q000276:immunology*