In vitro
The slight preference for Vps34 prevention by 3-Methyladenine probably arises from a hydrophobic ring specific to Vps34, which encircles the 3-methyl group of 3-Methyladenine. 3-Methyladenine has been reported to cause cancer cell death under both normal and starvation conditions. 3-Methyladenine could also suppress cell migration and invasion independently of its ability to inhibit autophagy, implying that 3-Methyladenine possesses functions other than autophagy suppression. 3-Methyladenine elicits caspase-dependent cell death that is independent of autophagy inhibition. Treatment with 5 mM 3-Methyladenine reduces the percentage of glucose-starved HeLa cells displaying GFP-LC3 puncta to 23%. The levels of LC3-I are increasing and the levels of LC3-II are decreasing between 12 and 48 hours in cells that are treated with 3-Methyladenine. Conversion of LC3-I to LC3-II is suppressed by 3-Methyladenine. Treatment of HeLa cells with 3-Methyladenine at 2.5 mM or 5 mM for one day does not affect cell viability, whereas treatment with 10 mM 3-Methyladenine for one day causes a 25.0% decrease in cell viability. Treatment of cells with 2.5, 5 or 10 mM 3-Methyladenine for two days causes 11.5%, 38.0% and 79.4% decrease in viability, respectively. 3-Methyladenine decreases cell viability in a time- and dose-dependent manner. 3-Methyladenine significantly shortens the duration of nocodazole-induced-prometaphase arrest.