In vivo use of all-trans retinoic acid prior to induction chemotherapy improves complete remission rate and increases rhodamine 123 uptake in patients with de novo acute myeloid leukemia

Expression and clinical significance of antiapoptotic gene (survivin) in NB4 and acute promyelocytic leukemia cells

To study survivin gene expression in APL cells and to explore its correlation with clinical manifestations. PML/RARα and survivin mRNA expression were analysed using RT-PCR. By treatment of ATRA, the survivin mRNA expression in NB4 cells gradually decreased with time and was almost undetectable in the 72th hour. Survivin was expressed in 67% of the 36 APL cases (de novo and relapse patients) with PML/RARα fusion gene expression. However, in 22 cases of remission stage patients without PML/RARα fusion gene expression, survivin was expressed in 36%. The survivin mRNA expression positive rate in de novo and relapse groups, and PML/RARα fusion gene L-type positive groups, was obviously higher than those in remission period groups and was significantly lower than those in acute leukemia groups. In 36 cases of de novo and relapse APL patients, all cases could obtain complete remission, irrespective of the survivin expression. APL patients expressed with survivin mRNA had DIC and serious infection (one patient died). The clinical symptom included slight skin or mucosa bleeding, fever, and asthenic for patients without the survivin mRNA expression. Later, two cases of APL patients with the survivin mRNA expression were treated by ATRA, induction differentiation sign in their peripheral blood and bone marrow figure was not obvious. It was concluded that the survive gene expression was lower in APL than those in any other types of leukemia, thus closely associated with clinical manifestation.

Differentiation therapy of acute myeloid leukemia

Acute Myeloid Leukemia (AML) is a predominant acute leukemia among adults, characterized by accumulation of malignantly transformed immature myeloid precursors. A very attractive way to treat myeloid leukemia, which is now called 'differentiation therapy', was proposed as in vitro studies have shown that a variety of agents stimulate differentiation of the cell lines isolated from leukemic patients. One of the differentiation-inducing agents, all-trans retinoic acid (ATRA), which can induce granulocytic differentiation in myeloid leukemic cell lines, has been introduced into clinics to treat patients with acute promyelocytic leukemia (APL) in which a PML-RARA fusion protein is generated by a t(15;17)(q22;q12) chromosomal translocation. Because differentiation therapy using ATRA has significantly improved prognosis for patients with APL, many efforts have been made to find alternative differentiating agents. Since 1,25-dihydroxyvitamin D3 (1,25D) is capable of inducing in vitro monocyte/macrophage differentiation of myeloid leukemic cells, clinical trials have been performed to estimate its potential to treat patients with AML or myelodysplastic syndrome (MDS). Unfortunately therapeutic concentrations of 1,25D can induce potentially fatal systemic hypercalcemia, thus limiting clinical utility of that compound. Attempts to overcome this problem have focused on the synthesis of 1,25D analogs (VDAs) which retain differentiation inducing potential, but lack its hypercalcemic effects. This review aims to discuss current problems and potential solutions in differentiation therapy of AML.

All-trans Retinoic Acid in Association with Low Dose Cytosine Arabinoside in the Treatment of Acute Myeoid Leukemia in Elderly Patients

All-trans retinoic acid (ATRA) has shown a synergistic activity in combination with cytosine arabinoside in vitro in the treatment of acute myeloid leukaemia (AML). In this paper we report the results of treatment with low dose cytosine arabinoside (LDAC) with or without ATRA in 28 patients with acute myeloid leukaemia aged over 60 years: 14 patients received only LDAC and the other 14 LDAC + ATRA. The patients of the 2 groups showed similar clinical features: in 10 patients AML developed after a myelodysplastic form and 4 patients presented a previous malignancy. All the patients received subcutaneous (sc) LDAC (15 mg twice a day for 14 days) and in 14 patients oral ATRA (45 mg/sqm in the same days) was added to LDAC; the courses were repeated every 4 weeks from diagnosis to relapse. The treatment was well tolerated and the patients could self-administer sc LDAC and oral ATRA at home. No statistically significant differences were observed in complete remission rate (21% vs. 50%, respectively) and resistant rate (57% vs. 29%), but the patients treated with the combination of the 2 drugs had a better time to treatment failure (15 weeks vs. 30 weeks, respectively) (P = 0.045) and a longer survival (37 weeks vs. 66 weeks) (P = 0.019). Our experience, although with a low number of patients, confirms the efficacy of ATRA in combination with sc LDAC in the treatment of AML in elderly patients.