Revista Brasileira de Hematologia e Hemoterapia Revista Brasileira de Hematologia e Hemoterapia
Rev Bras Hematol Hemoter 2017;39:237-43 DOI: 10.1016/j.bjhh.2017.03.006
Original article
Comparison of microRNA expression in high-count monoclonal B-cell lymphocytosis and Binet A chronic lymphocytic leukemia
Felipe Magalhães Furtadoa,, , Priscila Santos Scheuchera, Bárbara Amélia Santanaa, Dalila Lucíola Zanetteb, Rodrigo do Tocantins Caladoa, Eduardo Magalhães Regoa, Daniel Mazza Matosc, Roberto Passetto Falcãoa
a Faculdade de Medicina de Ribeirão Preto (FMRP), Ribeirão Preto, SP, Brazil
b Fundação Oswaldo Cruz (FIOCRUZ), Salvador, BA, Brazil
c Hospital Universitário Walter Cantídio (HUWC), Fortaleza, CE, Brazil
Recebido 30 Novembro 2016, Aceitaram 24 Março 2017
Abstract
Background

Evidence suggests that monoclonal B-cell lymphocytosis precedes all chronic lymphocytic leukemia cases, although the molecular mechanisms responsible for disease progression are not understood. Aberrant miRNA expression may contribute to the pathogenesis of chronic lymphocytic leukemia. The objective of this study was to compare miRNA expression profiles of patients with Binet A chronic lymphocytic leukemia with those of subjects with high-count monoclonal B-cell lymphocytosis and healthy volunteers (controls).

Methods

Twenty-one chronic lymphocytic leukemia patients, 12 subjects with monoclonal B-cell lymphocytosis and ten healthy volunteers were enrolled in this study. Flow cytometry CD19+CD5+-based cell sorting was performed for the chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis groups and CD19+ cells were sorted to analyze the control group. The expressions of miRNAs (miR-15a, miR-16-1, miR-29b, miR-34a, miR-181a, miR-181b and miR-155) were determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR).

Results

Significant differences between the expressions in the chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis groups were restricted to the expression of miR-155, which was higher in the former group. A comparison between healthy controls and monoclonal B-cell lymphocytosis/chronic lymphocytic leukemia patients revealed higher miR-155 and miR-34a levels and lower miR-15a, miR-16-1, miR-181a and miR-181b in the latter group.

Conclusions

Our results show a progressive increase of miR-155 expression from controls to monoclonal B-cell lymphocytosis to chronic lymphocytic leukemia. The role of miR-155 in the development of overt chronic lymphocytic leukemia in individuals with monoclonal B-cell lymphocytosis must be further analyzed.

Keywords
Monoclonal B-cell lymphocytosis, Chronic lymphocytic leukemia, microRNA
Rev Bras Hematol Hemoter 2017;39:237-43 DOI: 10.1016/j.bjhh.2017.03.006