Abstract: Objective: To investigate the inhibitory effect of Xue Lian Su (XLS), a kind of bacteriocin-like substance extracted from oral streptococcus sanguis, on ovarian cancer (OC) SKOV3 cell line and its possible molecular mechanism. Methods: The effects of XLS and paclitaxel on the activity of SKOV3 cells were detected by CCK-8 method. The effects of XLS on cell proliferation, invasion, and migration were detected by colony formation, Transwell, and cell scratch. Western blot and quantitative real-time polymerase chain reaction (qPCR) were used to analyze the regulation of XLS on phosphatidylinositol 3 kinase/protein kinase B (PI3K/Akt) pathway and related protein expression. Mitochondrial membrane potential, reactive oxygen species (ROS), and Ca²⁺ levels were detected to investigate XLS-induced mitochondrial apoptosis. Results: The viability of SKOV3 cells treated with XLS decreased with the increase of XLS concentration. XLS inhibited the proliferation, invasion, and migration of SKOV3 cells in a concentration-dependent manner. XLS inhibited the activation of PI3K/Akt signaling pathway, regulated the expression of related gene proteins, and induced apoptosis. XLS could reduce mitochondrial membrane potential, increase oxidative stress and Ca²⁺ imbalance, and further destroy cell structure and function. Conclusion: XLS can inhibit the proliferation, invasion, and migration of SKOV3 cells and induce apoptosis, showing the potential to significantly inhibit SKOV3 cells.

Key words: XLS, SKOV3 cell, proliferation, migration, invasion