Center of Drug Discovery, State Key Laboratory of Natural Medicines, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, PR China; Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, PR China. Electronic address: [Email]
The drug resistance and the poor water solubility are major limitations of paclitaxel (PTX) of based chemotherapy. To conquer the two problems, targeting folate (FA) receptor PTX-lytic peptides conjugates were synthesized and evaluated. Compared with PTX, FA-P3-PTX and FA-P7-PTX displayed significantly enhanced cell toxicity in many cancer cells, particularly drug resistant cancer cells MCF-7/PTX. FA-P7-PTX possessed stronger effect on cell toxicity (IC50 = 2.92 ± 0.2 μM), membrane disrupting activity and pro-apoptosis in MCF-7/PTX cells than FA-P3-PTX. Further investigation displayed that the anti-cancer mechanisms of FA-P3-PTX and FA-P7-PTX might be a mitochondrial impairment and caspase-3-dependent apoptotic cell death. Furthermore, the in vivo antitumor efficacy study confirmed that FA-P7-PTX performed more stronger potency in inhibition of tumors growth than PTX. The study demonstrated that conjugate FA-P7-PTX with superior properties for antineoplastic activity, which makes it a promising potential candidate for drug-resistant cancer therapy.