MiR15a/16 expression by B-1 cells resistant to quercertin treatment in vitro

• Grant number: 14/26059-4
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): March 01, 2015
• Effective date (End): December 31, 2015
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal researcher: Ana Flavia Popi
• Grantee: Yasmim Álefe Leuzzi Ramos
• Home Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Chronic lymphocytic leukemia (CLL) is an age-associated malignancy characterized by the expansion of CD5+ B-1 cells. The NZB mouse model of CLL, which similar to human CLL, have an age-associated increase in malignant B-1 clones and decreased expression of miR-15a/16. A systemic lentiviral delivery of miR-15a/16 ameliorate disease manifestations of CLL in this mouse model, and also decrease the B-1 cell population. Interestingly, it was observed that B-1 cells from NZB mice are more resistant to irradiation than cells from other mouse strain. In addition, the transfection of NZB B-1 cells with miR15/16-a induce cell death after irradiation. Our group recently described that Wnt/beta-catenin is important to B-1 cells survival in vitro. However, some B-1 cells became resistant to Wnt/beta-catenin signaling blockage by quercetin. Our aim is investigate expression of miR15/16-a by quercetin-resistant B-1 cells, in order to obtain data about molecular mechanisms involved in the apoptosis resistance and further correlate them to malignant transformation potential.