Diterpenoids from Euphorbia ebracteolata Hayata and their cytotoxic activity

Five undescribed diterpenoids (1-5) and thirteen known analogues (6-18) were isolated from the roots of Euphorbia ebracteolata Hayata. The cytotoxic activity of all isolates was evaluated against MDA-MB-231, HepG2 and MC38 cancer cell lines, with IC₅₀ values of 6.16 ± 0.85, 11.10 ± 0.13 and 6.48 ± 0.37 μM. Flow cytometry showed that compound 12 increased the apoptosis rate of MDA-MB-231 cells in a concentration-dependent manner. Western blot analysis indicated that compound 12 significantly upregulated pro-apoptotic Bax, downregulated anti-apoptotic Bcl-2, and inhibited the JAK2-STAT3 pathway. These findings demonstrated that compound 12 showed promising cytotoxic activity, warranting further investigation.