title: Anti-retinoic acid (RA) antibody binding to human premalignant oral lesions, which occurs less frequently than binding to normal tissue, increases after 13-cis-RA treatment in vivo and is related to RA receptor beta expression.
abstract: Nuclear retinoic acid receptor beta (RAR-beta) expression decreases in human premalignant oral lesions (POLs). RAR-beta suppression could result from a decrease in the cellular level of retinoids because RAR-beta gene transcription is enhanced by retinoids. To explore this hypothesis, we compared the binding of a monoclonal antibody (mAb) against all-transretinoic acid (RA; anti-RA mAbs) to normal oral tissue and POLs. All 7 normal specimens stained positive with the antibody compared to only 20 of 43 POLs; similarly, 7 of 7 normal specimens contained RAR-beta mRNA compared to only 14 of 43 POLs. Twenty-four specimens were available before and after a 3-month treatment with 13-cis-RA in vivo. Anti-RA mAb binding to these specimens increased from 10 of 24 before to 22 of 24 after treatment, and the expression of RAR-beta mRNA increased from 7 of 24 before to 21 of 24 after treatment, respectively. There was a strong agreement between the binding of anti-RA mAbs and the expression of RAR-beta. Thus, we propose that the binding of anti-RA mAbs reflects the level of retinoids in the tissues and that this level is related strongly to RAR-beta expression.
authors.affiliation: Department of Tumor Biology, University of Texas M. D. Adnerson Cancer Center, Houston 77030, USA.
authors.forename: X C
authors.initials: XC
authors.lastname: Xu
authors.forename: M H
authors.initials: MH
authors.lastname: Zile
authors.forename: S M
authors.initials: SM
authors.lastname: Lippman
authors.forename: J S
authors.initials: JS
authors.lastname: Lee
authors.forename: J J
authors.initials: JJ
authors.lastname: Lee
authors.forename: W K
authors.initials: WK
authors.lastname: Hong
authors.forename: R
authors.initials: R
authors.lastname: Lotan
mesh_terms: D000911:Antibodies, Monoclonal / Q000378:metabolism*; D006801:Humans; D015474:Isotretinoin / Q000627:therapeutic use; D009061:Mouth Mucosa / Q000378:metabolism*; D009062:Mouth Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D011230:Precancerous Conditions / Q000188:drug therapy / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000378:metabolism*; D014212:Tretinoin / Q000276:immunology / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; C082925:retinoic acid receptor beta; D014212:Tretinoin; D015474:Isotretinoin