ABSTRACT
Para conocer los estimulantes mitógenos más adecuados para la iniciación de la actividad mitótica de los blastos se utilizaronultivos de 20 muestras de células de leucemia aguda linfoblástica (LAL). Se analizaron diferentes concentraciones de fitohemaglutinina (PHA), lectina (Phitolacca americana) (FL) y 2-mercaptoetanol (2-ME) mediante la estimulación de cultivos celulares de 20 muestras. La mucoproteina extraída de las plantas (PHA) resultó ser el mejor activador de la mitosis y de la proliferación. A una concentración de 2.5 mg/ml, ocurrió la división celular; en su ausencia, no se observó proliferación celular. Por otra parte, la FL tuvo un efecto menor de la activación de la mitosis en los cultivos; y el 2-ME no presentó efecto alguno sobre la proliferación de estas células. Además, se observó que la acción mitogénica de la PHA implica la activación de la replicación del ADN celular, tal y como lo demostró la incorporación de [3H]-timidina
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Precursor Cell Lymphoblastic Leukemia-Lymphoma/immunology , Mitogens , Lymphocyte Activation/immunology , Cells, Cultured/ultrastructure , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Hematopoietic System/ultrastructureABSTRACT
The gross structure and the expression of the c-myc oncogene were analyzed in primary cells from 15 acute lymphoblastic leukemia patients. Southern blot analysis was used to detect possible alterations in the structure of this gene. Alterations (rearrangement and/or amplification) were observed in seven of the 15 samples studied. When the expression of MYC protein was evaluated by Western blot analysis, we found no correlation between c-myc gene alterations and p67 c-myc, which was expressed in the 15 samples studied. The analysis of expression also revealed various MYC-related proteins (115, 110 and 60 kD). These proteins were expressed at variable levels in all leukemic cells, other transformed cells, and in normal peripheral blood lymphocytes (PBL) induced to proliferate with interleukin 2. We detected the 110 kD and 40 kD MYC-related proteins in fresh normal PBL and in samples from patients in complete remission. These studies indicate that the c-myc alterations and protein expression are unrelated to percentage of leukemic blasts, cell morphology or immunophenotype. Our work shows that the expression of MYC-related proteins from 115, 60 and 40 kD is associated with mechanisms of cell activation, and perhaps these proteins may play a role in cellular proliferation-transformation.
