ANTIPROLIFERATIVE ACTIVITY OF RETINOIC ACID AND SOME NOVEL RETINOID DERIVATIVES IN BREAST AND COLORECTAL-CANCER CELL-LINES OF HUMAN-ORIGIN

Antiproliferative activities of all-trans-retinoic acid (RA, CAS 302-7 9-4) and some retinoid derivatives (all-trans-retinyl-beta-D-glucuroni de (RYG), ethyl-(1-O-retinoyl-beta-D-glucopyranoside)uronate (MRG), al l-trans-retinoic acid beta-D-galactopyranosyl ester (RGA), and all-tra ns-retinoic acid beta-D-glucopyranosyl ester (RGU)) were determined by microculture tetrazolium assay (MTT assay) and cell counting by Coult er Counter (CC) in breast (MCF7, MDA MB 231) and colon (SW 948) cancer cell lines of human origin. RA, MRG, RGU, and RGA (5, 25 mumol/l) wer e significantly more growth-inhibitory in MCF7 cells, which are known to be cellular retinoic acid-binding protein (cRABP) and cellular reti nol binding protein (cRBP) positive, than in MDA MB 231 cells which ar e cRABP and cRBP negative. RYG was active only in MDA MB 231 cells. RA , MRG, RGA and RGU (25 mumol/) stimulated the proliferation of SW 948 cells as determined by CC, whereas the MTT assay indicated an inhibiti on of cell growth.