ABSTRACT
BACKGROUND: Despite the advances in the cure rate for acute myeloid leukemia (AML), a considerable number of patients die from the disease due to the occurrence of multidrug resistance (MDR). Overexpression of the transporter proteins, such as P-glycoprotein (Pgp) and multidrug resistance-associated protein (MRP), confers resistance to the treatment of these leukemias. METHODS: To analyze the expression of the Pgp and MRP1 in patients with AML and determine their correlation between expression and demographic, clinical, and laboratorial variables, bone marrow and peripheral blood samples from 346 patients with a diagnosis of AML were assessed for the expression of Pgp and MRP1 by flow cytometry. RESULTS: The expression of Pgp and MRP1 was found in 111 (32.1%) and 133 (38.4%) patients, respectively, with greater prevalence in older patients and lower in children, while also observing a high incidence in patients with refractory, recurrence, and secondary disease in comparison with the cases of de novo AML. Regarding the laboratory findings, we observed an association between the expression of Pgp and MRP1 and CD34, CD7, and also M7, M5a, and M2-AML of French-American-British classification. CONCLUSIONS: The results showed that the detection of MDR phenotype by flow cytometry can be a molecular marker for prognosis of patients with AML.
Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/genetics , Multidrug Resistance-Associated Proteins/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers , Biomarkers, Tumor , Child , Child, Preschool , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Female , Flow Cytometry , Humans , Immunophenotyping , Infant , Leukemia, Myeloid, Acute/metabolism , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Multidrug Resistance-Associated Proteins/metabolism , Phenotype , Prognosis , Symptom Assessment , Young AdultABSTRACT
A surface plasmon resonance- (SPR-) based recognition method applying H-2 Ld:Ig/peptides complexes for ex vivo monitoring cellular immune responses during murine infection with Leishmania (Leishmania) amazonensis is described. Lymphocytes from lesion-draining popliteal lymph nodes were captured on a carboxylated sensor chip surface previously functionalized with H-2 Ld:Ig (DimerX) protein bound to synthetic peptides derived from the COOH-terminal region of cysteine proteinase B of L. (L.) amazonensis. In computational analysis, these peptides presented values of kinetic constants favorable to form complexes with H-2 Ld at neutral pH, with a Gibbs free energy ΔG° < 0. The assayed DimerX:peptide complexes presented the property of attaching to distinct T lymphocytes subsets, obtained from experimentally infected BALB/c mice, in each week of infection, thus indicating a temporal variation in specific T lymphocytes populations, each directed to a different COOH-terminal region-derived peptide. The experimental design proposed herein is an innovative approach for cellular immunology studies of a neglected disease, providing a useful tool for the analysis of specific T lymphocytes subsets.
