Abstract
Using a two-dimensional gel electrophoresis system (sodium dodecyl sulphate/acetic acid-urea-hexadecyltrimethylammonium bromide) coupled with fluorography, we investigated the synthesis of H1 isoproteins in leukemic cells obtained from peripheral blood of eight children suffering from acute lymphoblastic leukemia (ALL) (four T-ALL, three common ALL, and one B-ALL) and in normal peripheral lymphocytes. H1 degrees was synthesized in leukemic cells but not in normal lymphocytes. Inhibition of DNA synthesis with hydroxyurea and 1-beta-D- arabinofuranosylcytosine induced an increase of relative synthesis of H1 degrees in leukemic cells but did not induce any detectable synthesis of H1 degrees in normal lymphocytes. H1 degrees synthesis was also undetectable in peripheral lymphocytes of leukemic children in complete remission after chemotherapy and in lymphocytes of a homozygotic twin of a leukemic patient. H1 degrees may be a marker of malignant transformation of lymphocytes and as such could be of use for early detection of relapse in patients with acute lymphocytic leukemia in apparent complete remission.
