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.
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.
Xu
X C
XC
Department of Tumor Biology, University of Texas M. D. Adnerson Cancer Center, Houston 77030, USA.
Zile
M H
MH
Lippman
S M
SM
Lee
J S
JS
Lee
J J
JJ
Hong
W K
WK
Lotan
R
R
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*
D000911:Antibodies, Monoclonal; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; C082925:retinoic acid receptor beta; D014212:Tretinoin; D015474:Isotretinoin