Exogenous Selenoprotein V Induces Apoptosis in Murine Testicular Teratoma Cells via Mitochondrial Dysfunction and ROS Overproduction

This study explores the effects of exogenous SELENOV on cellular migration, viability, mitochondrial function, ROS production, and Ca²⁺ signaling in mouse fibroblast L-929 and testicular teratoma F-9 cells. In scratch assays, 50-100 µg/mL SELENOV significantly inhibited F-9 cell migration after 48 h, while in L-929 fibroblasts, only 100 µg/mL had a suppressive effect. Viability assays revealed strong cytotoxicity in F-9 cells. Critically, at a dose of 50 µg/mL (where the corresponding volume of solvent buffer alone was non-toxic), SELENOV reduced survival to 19%, triggering late apoptosis in 76% of cells, whereas in L-929 cells, comparable effects required 100 µg/mL. Mitochondrial depolarization (JC-1/Rhodamine-123 assays) was pronounced in F-9 cells even at 50 µg/mL, while L-929 cells responded only to 100 µg/mL. Similarly, 50 µg/mL SELENOV induced significant ROS overproduction in F-9 but not in L-929 cells, correlating with upregulated NOX1, NOX4, GPX3, and GPX4 expression. Ca²⁺ imaging showed dose-dependent [Ca²⁺]ᵢ elevation, with 50 µg/mL SELENOV inducing a sustained rise in F-9 cells, whereas L-929 cells required higher doses. Strikingly, 50 µg/mL SELENOV in F-9 cells downregulated BCL-2 and BCL-xL while upregulating pro-apoptotic BAX and PUMA, suggesting selective activation of intrinsic apoptosis. These results demonstrate that F-9 cancer cells are significantly more sensitive to SELENOV than normal fibroblasts, with 50 µg/mL sufficient to trigger mitochondrial dysfunction, oxidative stress, and apoptosis. The findings highlight SELENOV's potential as a targeted anticancer agent, particularly for germ cell tumors.