The Effect of Retinoids in Medulloblastoma Cell Culture

ABSTRACT

The retinoic acid, one of the most popular agents for chemoprevention can inhibit the proliferation of many cancer cells including neuroblastoma and glioblastoma but there is increasing demand reaccessing its in vitro inhibitory effect on the tumor proliferation because of poor responsiveness from recent clinical trial for malignant brain tumor with retinoic acid. If was known to effect on tumor cells by diffferentiation and apoptosis so that its effect was expected greater in pediatric brain tumor than in adult brain tumor, but there is no report on the effect of retinoic acid in medulloblastoma cell proliferation except all-trans and 13-cis retinoic acid. Therefore, we compared the effects of all-trans, 13-cis, and 9-cis retinoic acid and N-(4-hydroxyphenyl) retinamide to inhibit proliferation of medulloblastoma tumor cells. Medulloblastoma cells were derived from primary culture of patient's specimen. We estimated the rate of growth inhibition of each tumor cells using MTT assay in the concentration from 10-12 M to 10-5 M of all-trans, 13-cis, and 9-cis retinoic acid and N-(4-hydroxyphenyl) retinamide. Medulloblastoma cells showed more than 30% growth inhibition by all-trans, 12% by 13-cis, 20% by 9-cis retinoic acid and 7% by N-(4-hydroxyphenyl) retinamide at 14 days culture on the concentration of 10-6M. In conclusion, significanty and dramatic effect by, especially, all-trans retinoic acid, moderate response by 13-cis retinoic acid and variable or poor response by 9-cis retinoic acid and N-(4-hydroxyphenyl) retinamide.