Fig. 4

Overexpression of FAM3B decreases DNA fragmentation and membrane exposure of phospholipid phosphatidylserine (PS). a Flow cytometric analysis of DNA fragmentation by propidium iodide (PI) staining of DU145 cells upon treatment with TNF-α (0.2 ng/mL, 2 ng/mL and 20 ng/mL) + CHX for 24 h. Hypodiploid cells are considered as DNA-fragmented cells (apoptotic cells) shown on the left side of the representative histograms. b Cells overexpressing FAM3B show lower rates of DNA fragmentation than control cells. Y-axis of bars shows mean rate ± SE of fragmented cells in three independent experiments. c Identification of PS exposure by annexin-V-FITC staining of DU145 cells following treatment with TNF-α (0.2 ng/mL, 2 ng/mL and 20 ng/mL) + CHX for 24 h. Representative dot plots show annexin-V positive cells (lower right quadrant) and annexin-V + PI positive cells (upper right quadrant), summing total apoptotic cells (d). Cells overexpressing FAM3B have lower rates of PS exposure than control cells. Y-axis of bars shows mean rate ± SD of total annexin-V positive cells in three independent experiments. Statistical differences were determined by Student- t test. (* p < 0.05; ** p < 0.01)