Fig. 7.

Functional studies in APL-derived NB4 cells stably over-expressing the S100A3 gene. NB4 cells were stably infected with a void lentivirus vector (pCDH-CMV) or the same lentivirus containing the S100A3 full-length cDNA (S100A3). Transfected cells were selected in puromycin for 10 days obtaining the following cell populations: pCDH/NB4 and S100ox/NB4. a Cells were treated vehicle (DMSO) and the indicated concentrations of ATRA for 24 h. pCDH/NB4 and S100ox/NB4 cell extracts were subjected to western blot analysis with anti-RARα, anti-S100A3 and anti-actin antibodies. M.W. = molecular weights of the indicated proteins. b The indicated NB4 derived cell populations were treated with vehicle and ATRA (10^–7 M) for up to 7 days. The growth of each cell populations was evaluated by counting the number of viable cells. Each experimental point is the mean ± S.E. of three independent cell cultures. **Significantly lower relative to the corresponding ATRA-treated pCDH/NB4 controls (Student’s test p < 0.01). c pCDH/NB4 and S100ox/NB4 cells were treated with ATRA (10^–8 M) for 3 days. Cells were subjected to the NBT assay. Each experimental point is the mean ± S.E. of three independent cell cultures. **Significantly different (p < 0.01 according to a two-way Student’s t-test). d pCDH/NB4 and S100ox/NB4 cells were treated with ATRA (10^–8 M) for 2 days. Cells were subjected to FACS analyses for the CD11b, CD11c, CD38, and CD33 surface markers, as indicated. The results are representative of two other independent experiments. e pCDH/NB4 and S100ox/NB4 cells were treated with vehicle or ATRA (10^–7 M) for 1 day. Cell extracts were subjected to western blot analysis for the indicated proteins using specific antibodies. M.W. = molecular weights of the indicated proteins. The results are representative of two other independent experiments