Recent Advances in the Application of Cucurbitacin B as an Anticancer Agent.

Cucurbitacin B (CuB), a tetracyclic triterpenoid compound isolated from Cucurbitaceae plants, exhibits inhibitory effects on various tumor cells (e.g., liver, gastric, and colorectal cancer cells). Since the 1970s-1980s, cucurbitacin tablets containing CuB have been used as an adjuvant therapy for chronic hepatitis and primary liver cancer. CuB exerts anticancer effects through multiple mechanisms: inducing apoptosis, cell cycle arrest (G2/M or S phase), autophagy, and cytoskeleton disruption; inhibiting migration, invasion, and angiogenesis (via VEGF/FAK/MMP-9 and Wnt/β-catenin pathways); regulating metabolic reprogramming and immune responses; inducing pyroptosis, ferroptosis, and epigenetic changes; and reversing tumor drug resistance. These effects are associated with signaling pathways like JAK/STAT, PI3K/Akt/mTOR, and FOXM1-KIF20A. To improve its application potential, strategies such as structural modification (e.g., NO donor conjugation), combination therapy (with gemcitabine or cisplatin), and nanomaterial-based delivery (e.g., liposomes and exosome-mimicking nanoparticles) have been developed to enhance efficacy, reduce toxicity, and improve bioavailability. CuB shows broad-spectrum anticancer activity, but further research is needed to clarify the mechanisms underlying its cell-specific sensitivity and interactions with the immune system. This review systematically summarizes the physicochemical properties, anticancer mechanisms, and strategies for applying CuB and suggests future research directions, providing references for scientific research and clinical translation.