title: Retinoic acid and calcitriol inhibition of growth and NADH oxidase of normal and immortalized human keratinocytes.
abstract: Plasma membranes were isolated by aqueous two-phase partition from normal human keratinocytes (HKc) and from human keratinocytes immortalized with human papillomavirus type 16 DNA (HKc/HPV16). The NADH oxidase of plasma membrane vesicles of normal HKc was stimulated by epidermal growth factor whereas that of HKc/HPV16 was not. The NADH oxidase of the plasma membranes from both normal HKc and HKc/HPV16 was inhibited by calcitriol (1 alpha-1,25-dihydroxy vitamin D-3) and retinoic acid. However, with plasma membranes from HKc/HPV16 the NADH oxidase was more susceptible to inhibition by retinoic acid than were membranes from normal HKc. Similarly, clonal growth of HKc/HPV16 was inhibited by retinoic acid at lower concentrations than normal HKc whereas inhibition of clonal growth of normal HKc and HKc/HPV16 by calcitriol showed similar dose-dependencies. Comparing normal HKc and HKc/HPV16, the results demonstrate parallel inhibition of clonal growth and NADH oxidase by both retinoic acid and calcitriol of HKc/HPV16 but not of normal HKc. These results suggest that an increased sensitivity of the plasma membrane NADH oxidase of HKc/HPV16 to retinoic acid may be related to the increased sensitivity of these cells to growth control by retinoic acid. In addition, since plasma membrane NADH oxidase of HKc/HPV16 shows altered responsiveness to growth modulators such as EGF, retinoic acid and calcitriol, it appears that HKc/HPV16 express an NADH oxidase with different characteristics than those of normal HKc.
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, Purdue University, West Lafayette, IN.
authors.forename: D J
authors.initials: DJ
authors.lastname: Morré
authors.forename: D M
authors.initials: DM
authors.lastname: Morré
authors.forename: M
authors.initials: M
authors.lastname: Paulik
authors.forename: A
authors.initials: A
authors.lastname: Batova
authors.forename: A M
authors.initials: AM
authors.lastname: Broome
authors.forename: L
authors.initials: L
authors.lastname: Pirisi
authors.forename: K E
authors.initials: KE
authors.lastname: Creek
mesh_terms: D002117:Calcitriol / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects*; D002461:Cell Line, Transformed; D002462:Cell Membrane / Q000187:drug effects; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors*; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors*; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D009097:Multienzyme Complexes; D014212:Tretinoin; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D002117:Calcitriol