Seon-Hee Kim^1,, Dong Seok Lee^1,

Cervical cancer remains a significant global health burden, necessitating the development of safer and more effective therapeutic agents. Orostachys japonicus, a traditional medicinal herb, has shown promising anti-cancer activity, but its molecular mechanisms in cervical cancer cells have not been fully elucidated. We investigated the pro-apoptotic effects of the ethyl acetate fraction of O. japonicus (E-OJ) on HeLa cells and compared its activity to known phenolic constituents (kaempferol, quercetin, and gallic acid). Apoptosis was assessed by Annexin V/PI flow cytometry and DAPI staining. Western blot analysis was used to examine NF-κB and MAPK signaling pathways, as well as caspase-3 activation. The role of ERK signaling was further evaluated using the ERK-specific inhibitor U0126. E-OJ treatment induced significant, dose-dependent apoptosis in HeLa cells, accompanied by nuclear fragmentation and chromatin condensation. Compared to individual compounds, E-OJ exhibited greater apoptotic efficacy. Mechanistically, E-OJ suppressed NF-κB signaling by blocking nuclear translocation of the NF-κB p65 subunit. Among the MAPK pathways, only ERK1/2 was activated by E-OJ. Inhibition of ERK1/2 with U0126 attenuated caspase-3 cleavage, indicating that ERK signaling mediates E-OJ-induced apoptosis through a caspase-3-dependent mechanism. These findings suggest that E-OJ induces apoptosis in cervical cancer cells by suppressing NF-κB activation and promoting ERK1/2-mediated caspase-3 activation. The superior efficacy of E-OJ compared to its individual phenolic components highlights its therapeutic potential as a natural anti-cancer agent.

Orostachys japonicus, cervical cancer, apoptosis, NF-κB, ERK1/2