Figure 6From: MEIS1, PREP1, and PBX4 Are Differentially Expressed in Acute Lymphoblastic Leukemia: Association of MEIS1 Expression with Higher Proliferation and Chemotherapy ResistanceModulation of MEIS1 and PREP1 expression after etoposide treatment. A) Jurkat, CEM, and K562 cells were treated with 170 μM etoposide for 1 and 2 h; thereafter, total RNA was extracted and retrotranscribed. Real time-PCR assays were performed to determine the relative expression levels of MEIS1 and PREP1. Expression analysis was carried out by normalizing with non-treated cells and employing RPL32 as reference gene. The bars represent means ± Standard deviations (SD) of two independent experiments; B) Percentage of apoptotic cells induced by etoposide treatment. Jurkat, CEM, and K562 cells were treated with 170 μM etoposide; the percentage of apoptotic cells was measured using Annexin-V-FLUOS. The bars represent means ± Standard deviations (SD) of three independent experiments. C) MEIS1-silenced (LVX-E9 and -E13) cells were treated with 170 μM etoposide for 12 and 24 hours. Parental cells (Jurkat and K562) or empty vector-silenced cells (LVX) were also used. After etoposide treatment WST-1 was added to cell cultures and incubate for 3 additional hours. The percentage of cell survival was calculated measuring Optical density (OD) at 450 nm (OD of untreated cells was set as 100%). Statistical differences were calculated at the end point of the curves using 2 way ANOVA analysis and Bonferroni posttest, (*) significances are shown between groups only when p ≤ 0.05.Back to article page