Effects of retinoids on in vitro differentiation of bone marrow cells in the myelodysplastic syndrome

Abstract

The effect of retinoids on cell differentiation in the myelodysplastic syndrome was studied in short-term liquid cultures of bone marrow from 13 patients. After incubation with 13-cis-retinoic acid there was a significant decrease in the percentages of promyelocytes and in Leu-M3-binding cells. Lue-M3 is mainly a monocyte marker, and retinoids thus seem to induce a shift from monocytoid to myeloid differentiation. Patients with refractory anemia with an excess of blasts responded the most, and did also show a significant decrease in OKIa1-binding cells. Etretinate, on the other hand, did not show any differentiation-inducing activity. The results support earlier reports that retinoic acid might be useful in the treatment of the myelodysplastic syndrome. Whether this in vitro technique offers a possibility to predict the clinical outcome remains to be shown.