Lysine-Specific Demethylase 1 (LSD1) Inhibitor S2101 Induces Autophagy via the AKT/mTOR Pathway in SKOV3 Ovarian Cancer Cells
Shujun Feng, Ye Jin, Mengjiao Cui, Jianhua Zheng
(Department of Obstetrics and Gynecology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China (mainland))
Med Sci Monit 2016; 22:4742-4748
S2101 is one of the most potent LSD1 inhibitors, which can inhibit ovarian cancer cells viability. This study aimed to detect the mechanism behind the anticancer properties of S2101 in SKOV3 ovarian cells.
MATERIAL AND METHODS: Cell viability was tested by Cell Counting Kit-8 (CCK-8) assay. Cellular apoptosis and autophagy were evaluated by flow cytometric analysis using Annexin-V/PI staining methods and Green fluorescent protein (GFP)-fused-LC3 (GFP-LC3), respectively. Western blotting was performed for analyzing the Bax, Bcl-2, mTOR, p- mTOR, p62, LC3-I, LC3-II, AKT, and p-AKT protein expression.
RESULTS: Our results show that the proportion of early apoptotic and late apoptotic cells increased significantly for cells treated with S2101 at a concentration of 100 μM for 48 h. Treatment of S2101 in SKOV3 cells resulted in upregulation of Bax and downregulation of Bcl-2 in a time-dependent manner, indicating that S2101 can induce apoptosis in SKOV3. There was a downward trend in the expression of p62 when the SKOV3cells were treated with 100 µm S2101 for 12 h, 24 h and 48 h. The conversion of LC3-I to LC3-II was increased significantly at 24 h and 48 h. Autophagy was induced by S2101 in SKOV3 cells, evidenced by an increase in punctuate localization of GFP-LC3 and a change in expression of autophagy-related proteins.
CONCLUSIONS: S2101 treatment decreased the levels of phosphorylated AKT and mTOR. S2101 inhibits SKOV3 cells viability and induces apoptosis and autophagy. The AKT/mTOR signaling pathway was found to be affected by S2101.
Keywords: Apoptosis Regulatory Proteins - metabolism, Apoptosis - drug effects, Autophagy - drug effects, Cell Growth Processes - drug effects, Cell Line, Tumor, Cell Survival - drug effects, Cyclopropanes - pharmacology, Enzyme Inhibitors - pharmacology, Female, Histone Demethylases - metabolism, Humans, Ovarian Neoplasms - pathology, Phenyl Ethers - pharmacology, Proto-Oncogene Proteins c-akt - metabolism, Signal Transduction - drug effects, TOR Serine-Threonine Kinases - metabolism