Kivonat:
Polymorphisms of the ABCB1 (MDR1) and ABCG2 (BCRP) genes were reported to alter
the expression and function of these drug transporters. Both proteins are present
at the main pharmacokinetic barriers including the blood-brain barrier. Data from
291 children with acute lymphoblastic leukaemia were analysed in this
retrospective study. ABCB1 3435T>C, 2677G>T/A, 1236C>T and ABCG2 421C>A, 34G>A
genotypes were determined. Encephalopathy episodes were more frequent among those
with ABCB1 3435TT genotype than in the 3435CC/CT group (odds ratio (OR) 3.5;
P=0.03). Patients with the ABCG2 421A allele tended to have more complications
than wild type homozygotes (OR=2.0; P=0.25). The rate of the adverse effect was
similar in those harbouring no or only one of the predisposing genotypes, that
is, either ABCB1 3435TT or ABCG2 421AA/AC. However, significantly more children
suffered encephalopathy in the group with both predisposing genotypes (OR=12.3;
P=0.005). In conclusion, these variations exert synergistic effect in
predisposing patients to toxic neurological complications of chemotherapy.
