Role of anthracyclines in the treatment of adult acute lymphoblastic leukemia

High Throughput Screening Identifies a Novel Compound Protecting Cardiomyocytes from Doxorubicin-Induced Damage

Antracyclines are effective antitumor agents. One of the most commonly used antracyclines is doxorubicin, which can be successfully used to treat a diverse spectrum of tumors. Application of these drugs is limited by their cardiotoxic effect, which is determined by a lifetime cumulative dose. We set out to identify by high throughput screening cardioprotective compounds protecting cardiomyocytes from doxorubicin-induced injury. Ten thousand compounds of ChemBridge's DIVERSet compound library were screened to identify compounds that can protect H9C2 rat cardiomyocytes against doxorubicin-induced cell death. The most effective compound proved protective in doxorubicin-treated primary rat cardiomyocytes and was further characterized to demonstrate that it significantly decreased doxorubicin-induced apoptotic and necrotic cell death and inhibited doxorubicin-induced activation of JNK MAP kinase without having considerable radical scavenging effect or interfering with the antitumor effect of doxorubicin. In fact the compound identified as 3-[2-(4-ethylphenyl)-2-oxoethyl]-1,2-dimethyl-1H-3,1-benzimidazol-3-ium bromide was toxic to all tumor cell lines tested even without doxorubicine treatment. This benzimidazole compound may lead, through further optimalization, to the development of a drug candidate protecting the heart from doxorubicin-induced injury.

Granulocyte colony-stimulating factor (G-CSF, filgrastim) after or during an intensive remission induction therapy for adult acute lymphoblastic leukaemia: effects, role of patient pretreatment characteristics, and costs

An early intensive anthracycline therapy can improve therapeutic outcome in adult acute lymphoblastic leukaemia (ALL) but is usually associated with marked myelosuppressive effects and significant morbidity by infections. To reduce this risk, we employed granulocyte colony-stimulating factor (G-CSF, filgrastim 5 microg/kg/d) as an adjunct to a myelotoxic, 14-day long induction regimen with idarubicin-vincristine-L-asparaginase-prednisone (IVAP). Owing to changes in study design, patients received 'late' (n = 28) or 'early' (n = 37) G-CSF from days 15 or 4 of IVAP, respectively, until resolution of severe neutropenia. Study endpoints included time to recovery from neutropenic nadir, duration of neutropenia <0.5 x 10(9)/l, incidence of infectious complications, assessment of variables affecting G-CSF response, clinical outcome and costs. Sixty-five consecutive cases were evaluable. Patients in early G-CSF group recovered significantly faster from the neutropenic nadir (p < 0.002), contracted less infectious complications (p = 0.007), and required less intravenous antibiotic (p = 0.008) and antifungal (p = 0.002) medications. Although these reductions did not compensate for the increased G-CSF treatment cost, the overall supportive care cost was not significantly increased by early G-CSF. Interestingly, T-ALL phenotype (p = 0.02) and higher neutrophil presentation count (p = 0.03) were associated with a shorter neutropenic course even with late G-CSF. Early G-CSF may be a valid approach to mitigate chemotherapy-induced neutropenia of IVAP and other similarly myelosuppressive adult ALL regimens.