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1. Chelidonine (Stylophorin) isolated from Chelidonium majus efficiently induced apoptosis in HeLa cells through possible alteration of p38-p53 and AKT PI3 kinase signalling pathways. 2. Chelidonine is a promising model compound for overcoming MDR and for enhancing cytotoxicity of chemotherapeutics, especially against leukaemia cells, its efficacy needs to be confirmed in animal models. 3. Chelidonine may be a potential therapeutic agent against metastasis of invasive human cancer cells, exhibits antimigratory and antiinvasive effects in MDA-MB-231 cells, by suppressing COL-induced integrin signaling, through inhibiting the formation of the IPP complex and subsequent downregulation of IPP downstream signaling molecules, such as Akt and ERK1 2.

Paclitaxel (Taxol) is a natural product and a microtubule polymer stabilizer. Paclitaxel has anti-tumor activity and causes cell death by inducing mitotic arrest, apoptosis, and cell autophagy.

Ursolic acid (Prunol) is a natural product, a pentacyclic triterpene carboxylic acid extracted from Rhododendron caprifolium. Ursolic acid has anti-tumor, anti-inflammatory, anti-bacterial and hypoglycemic activities.

Etoposide (VP-16-213) is a topoisomerase II inhibitor that inhibits DNA synthesis by forming a complex with topoisomerase II and DNA (IC50=60.3 μM). Etoposide has antitumor activity and induces apoptosis and autophagy.

Irinotecan (CPT-11), a derivative of camptothecin, is an inhibitor of DNA topoisomerase I (Topo I). Irinotecan has antitumor activity by preventing DNA strand reattachment through binding to the Topo I complex, resulting in double-stranded DNA breaks and cell death.

Sodium dichloroacetate (BCA) , a specific inhibitor of pyruvate dehydrogenase kinase (PDK) with IC50 values of 183 and 80 μM for PDK2 and PDK4 respectively, has been shown to derepress a mitochondrial potassium-ion channel axis, trigger apoptosis in cancer cells, and inhibit tumor growth.