CD34-related coexpression of MDR1 and BCRP indicates a clinically resistant phenotype in patients with acute myeloid leukemia (AML) of older age

Clinical resistance to chemotherapy in acute myeloid leukemia (AML) is associated with the expression of the multidrug resistance (MDR) proteins P-glycoprotein, encoded by the MDR1/ABCB1 gene, multidrug resistant-related protein (MRP/ABCC1), the lung resistance-related protein (LRP), or major vault protein (MVP), and the breast cancer resistance protein (BCRP/ABCG2). The clinical value of MDR1, MRP1, LRP/MVP, and BCRP messenger RNA (mRNA) expression was prospectively studied in 154 newly diagnosed AML patients ≥60 years who were treated in a multicenter, randomized phase 3 trial. Expression of MDR1 and BCRP showed a negative whereas MRP1 and LRP showed a positive correlation with high white blood cell count (respectively, p < 0.05, p < 0.001, p < 0.001 and p < 0.001). Higher BCRP mRNA was associated with secondary AML (p < 0.05). MDR1 and BCRP mRNA were highly significantly associated (p < 0.001), as were MRP1 and LRP mRNA (p < 0.001) expression. Univariate regression analyses revealed that CD34 expression, increasing MDR1 mRNA as well as MDR1/BCRP coexpression, were associated with a lower complete response (CR) rate and with worse event-free survival and overall survival. When adjusted for other prognostic actors, only CD34-related MDR1/BCRP coexpression remained significantly associated with a lower CR rate (p = 0.03), thereby identifying a clinically resistant subgroup of elderly AML patients

Bendamustine compared with chlorambucil in previously untreated patients with chronic lymphocytic leukaemia: updated results of a randomized phase III trial

The efficacy of bendamustine versus chlorambucil in a phase III trial of previously untreated patients with Binet stage B/C chronic lymphocytic leukaemia (CLL) was re-evaluated after a median observation time of 54months in May 2010. Overall survival (OS) was analysed for the first time. At follow-up, investigator-assessed complete response (CR) rate (21.0% vs 10.8%), median progression-free survival (21.2 vs 8.8months; P65 years, responders and non-responders. However, patients with objective response or a CR experienced a significantly longer OS than non-responders or those without a CR. Significantly more patients on chlorambucil progressed to second/further lines of treatment compared with those on bendamustine (78.3% vs 63.6%; P=0.004). The benefits of bendamustine over chlorambucil were achieved without reducing quality of life. In conclusion, bendamustine is significantly more effective than chlorambucil in previously untreated CLL patients, with the achievement of a CR or objective response appearing to prolong OS. Bendamustine should be considered as a preferred first-line option over chlorambucil for CLL patients ineligible for fludarabine, cyclophosphamide and rituximab