Evaluation of micronucleated lymphocytes, constitutional karyotypes and anti-p53 antibodies in 21 children with various malignancies

The implication of environmental carcinogens in childhood cancer is still u nknown. To assess a possible link between DNA damage and alterations of the tumor suppressor gene p53, blood samples of 21 children with malignancies were examined for the presence of micronuclei in lymphocytes using the cyto kinesis blocked micronucleus assay (CBMA). The constitutional karyotypes we re analyzed for chromosome abnormalities and the presence of anti-p53 antib odies in blood sera was evaluated by an enzyme-linked immune sorbent assay (ELISA). A control group of 20 children was also included. The rates of mic ronucleated cells were 5.1 parts per thousand +/- 3.9 and 2.4 parts per tho usand +/- 2.3 for the cancer and control groups, respectively. The differen ce between the groups were statistically significant (P < 0.05 by the Mann- Withney rank sum test). Two children in the cancer group showed extensive c hromosome breakage in lymphocytes. The sera of two other children from the cancer group and of one child from the control group contained anti-p53 ant ibodies. Chromosome breakage and anti-p53 antibodies from the five children were associated with increased micronucleated cell rates. The results of t he present study suggest that genotoxic events can occur in the lymphocytes of children with a cancerous state. (C) 2000 Published by Elsevier Science B.V. All rights reserved.