Treatment Outcome of Multidrug Resistance Related mRNA Expression and c-Jun-N-Terminal Kinase Activity in Patients with Acute Myeloid Leukemia

Abstract The prognosis for younger adults (≤ 55–60 years) with acute myeloid leukemia (AML) has improved during the last four decades. However, there has been little progress in the treatment of older adults. This disappointing observation is important because the median age of patients with AML is about 70 years. Approximately 60%–80% of younger adults with AML achieve complete remission (CR) with the cytotoxic agents cytarabine and an anthracycline such as daunorubicin or idarubicin or the anthracenedione mitoxantrone. However, only 30%–40% of such patients are alive and disease-free at 5 years. Among older adults, CR is achieved in 40%–55%, but there are very few long-term survivors. Many studies have evaluated the impact of alternative doses and schedules, as well as additional cytotoxic drugs, on the prognosis for this group of patients. The outcome has not improved substantially beyond that achieved with conventional doses of an anthracycline and cytarabine followed by high-dose cytarabine consolidation. Several factors identified at diagnosis can predict outcome. The most important of these is the karyotype of the leukemic cells. Another critical factor is the presence of transmembrane transporter proteins, which confer multidrug resistance and mutations in or overexpression of specific genes such as WT1, C/EBPα, BAX, and BCL-2/BAX ratio, BAALC, EVI1, KIT and FLT3. The development of specific agents directed at gene mutations, signal transduction pathways and unique cell surface antigens provide the foundation for new therapeutic strategies. Such agents include the immunoconjugate gemtuzumab ozogamicin, multidrug resistance inhibitors, farnesyltransferase inhibitors, histone deacetylase and proteosome inhibitors, antiangiogenesis agents, FLT3 inhibitors, apoptosis inhibitors, and nucleoside analogs. All of these agents can potentially address the heterogeneous abnormalities in AML and significantly improve the outcome for patients.

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Mitoxantrone, Etoposide, and Cyclosporine Therapy in Pediatric Patients With Recurrent or Refractory Acute Myeloid Leukemia

Journal of Clinical Oncology ◽

10.1200/jco.2000.18.9.1867 ◽

2000 ◽

Vol 18 (9) ◽

pp. 1867-1875 ◽

Cited By ~ 32

Author(s):

Gary V. Dahl ◽

Norman J. Lacayo ◽

Nathalie Brophy ◽

Kyriaki Dunussi-Joannopoulos ◽

Howard J. Weinstein ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Multidrug Resistance ◽

Myeloid Leukemia ◽

Remission Rate ◽

Serum Levels ◽

Cyclosporine Therapy ◽

Mdr1 Expression ◽

Drug Doses ◽

Refractory Acute Myeloid Leukemia ◽

Acute Myeloid

PURPOSE: To determine the remission rate and toxicity of mitoxantrone, etoposide, and cyclosporine (MEC) therapy, multidrug resistance-1 (MDR1) status, and steady-state cyclosporine (CSA) levels in children with relapsed and/or refractory acute myeloid leukemia.PATIENTS AND METHODS: MEC therapy consisted of mitoxantrone 6 mg/m2/d for 5 days, etoposide 60 mg/m2/d for 5 days, and CSA 10 mg/kg for 2 hours followed by 30 mg/kg/d as a continuous infusion for 98 hours. Because of pharmacokinetic interactions, drug doses were decreased to 60% of those found to be effective without coadministration of CSA. MDR1 expression was evaluated by reverse transcriptase polymerase chain reaction, flow cytometry, and the ability of CSA at 2.5 μmol/L to increase intracellular accumulation of3H-daunomycin in blasts from bone marrow specimens.RESULTS: The remission rate was 35% (n = 23 of 66). Overall, 35% of patients (n = 23) achieved complete remission (CR), 12% of patients (n = 8) achieved partial remission, and 9% of patients (n = 6) died of infection. Exposure to CSA levels of greater than 2,400 ng/mL was achieved in 95% of patients (n = 56 of 59). Toxicities included infection, cardiotoxicity, myelosuppression, stomatitis, and reversible increases in serum creatinine and bilirubin. In most who had relapsed while receiving therapy or whose induction therapy had failed, response was not significantly different for MDR1-positive and MDR1-negative patients.CONCLUSION: Serum levels of CSA capable of reversing multidrug resistance are achievable in children with acceptable toxicity. The CR rate of 35% achieved in this study is comparable to previously reported results using standard doses of mitoxantrone and etoposide. The use of CSA may have improved the response rate for the MDR1-positive patients so that it was not different from that for the MDR1-negative patients.

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