title: Evaluation of 9-cis retinoic acid for a new remedy of human retinoblastoma.
abstract: We investigated the effect of two isomers of retinoic acid (RA), all-trans RA and 9-cis RA, on the proliferation of Y79 human retinoblastoma cells. The two isomers inhibited the cell proliferation in a concentration-dependent manner. The IC50 for this inhibition by all-trans RA and 9-cis RA was 1.50 and 0.15 microM, respectively. The inhibitory effect of 9-cis RA on Y79 cell growth was observed within 24 hr, thereafter the cell number was gradually decreased. In contrast, no inhibition by all-trans RA of Y79 cell growth was observed within 24 hr, thereafter the cell number was slightly increased. In these cases, the cell viability at 4 days after the addition of 9-cis RA and all-trans RA was more than 90% and 95%, respectively. These results indicate that the two RA inhibit the proliferation of Y79 human retinoblastoma cells without inducing the cell death and that the effect of 9-cis RA on the inhibition of Y79 cell growth is much greater than that of all-trans RA.
authors.affiliation: Department of Ophthamology, Hiroshima University School of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tsukamoto
authors.forename: T
authors.initials: T
authors.lastname: Kurokawa
authors.forename: K
authors.initials: K
authors.lastname: Hirata
authors.forename: S
authors.initials: S
authors.lastname: Ishibashi
authors.forename: H K
authors.initials: HK
authors.lastname: Mishima
mesh_terms: D000077556:Alitretinoin; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D020128:Inhibitory Concentration 50; D012175:Retinoblastoma / Q000188:drug therapy* / Q000473:pathology; D013997:Time Factors; D014212:Tretinoin / Q000494:pharmacology* / Q000627:therapeutic use; D014343:Trypan Blue; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D000077556:Alitretinoin; D014212:Tretinoin; D014343:Trypan Blue