Elephantopin is a sesquiterpene lactone natural product isolated from the medicinal plant *Elephantopus scaber* L. (Asteraceae). It is characterized by a germacranolide skeleton with an α-methylene-γ-lactone moiety, a structural feature commonly associated with biological activity in many sesquiterpene lactones. This compound has been extensively studied for its potent anticancer and anti-inflammatory properties. Research indicates that elephantopin exhibits significant cytotoxic activity against a wide range of human cancer cell lines, including breast, lung, liver, and colon cancers. Its proposed mechanisms of action involve the induction of apoptosis (programmed cell death), cell cycle arrest, and the inhibition of NF-κB signaling pathways. The α-methylene-γ-lactone group is known to react with nucleophilic thiol groups in proteins, such as those in the p65 subunit of NF-κB, contributing to its anti-inflammatory and pro-apoptotic effects. Due to its promising bioactivity profile, elephantopin serves as a valuable lead compound in drug discovery for oncology. It is also a key reference standard in phytochemical and pharmacological research related to traditional herbal medicines.