[Detection and evaluation of bcl-x and bcl-2 gene expression in blasts from patients with acute leukemia]

To investigate the expression of bcl-x and bcl-2 genes in bone marrow cells of acute leukemia and their effects on response to chemotherapy.

Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the mRNA expressions of bcl-xL, bcl-xs and bcl-2 in blast cells from 34 acute leukemia(AL) patients.

The expression of bcl-xL and bcl-2 or both in blast cells from 34 AL patients was higher than that in complete remission patients and normal subjects. The expression of bcl-xL and bcl-2 in relapsed patients was increased by 1.8 and 1.9 fold, respectively, compared with that in the newly diagnosed patients(P < 0.01). However, no relationship was found between the expression of bcl-xs and the relapse and chemotherapeutic response of the AL patients. There were positive correlations between the expression of bcl-xL and bcl-2 or bcl-xL and bcl-xs. The expression level of bcl-xL and bcl-2 in the patients with poor response to chemotherapy was significantly higher than that in the patients with better response. Treatment failure occurred in 80.0%, 91.7% and 100.0% of the patients with overexpression of bcl-xL and bcl-2 and both, respectively.

Overexpression of bcl-xL and bcl-2 may imply the lower sensitivity of the leukemic cells to chemotherapy and higher risk of relapse.