Significant increase of anticancer efficacy in vitro and in vivo of liposome entrapped ruthenium(II) polypyridyl complexes

• Published in: European journal of medicinal chemistry Vol. 257; p. 115541
• Main Authors: Chen, Yichuan, Li, Wenlong, Yang, Yan, Zhong, Ruitong, Hu, Huiyan, Huang, Chunxia, Chen, Jing, Liang, Lijuan, Liu, Yunjun
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 05.09.2023
• Subjects: Antitumor in vitro and vivo; Ferroptosis; Molecular docking; RNA-sequence; Ru(II) complexes and liposomes; Western blot analysis; Antitumor in vitro and vivo; Ferroptosis; RNA-sequence; Western blot analysis; Molecular docking; Ru(II) complexes and liposomes
• ISSN: 0223-5234; 1768-3254
• DOI: 10.1016/j.ejmech.2023.115541

Two polypyridyl ruthenium(II) complexes [Ru(DIP)2(BIP)](PF6)2 (DIP = 4,7-diphenyl-1,10-phenanthrolie, BIP = 2-(1,1′-biphenyl-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline, Ru1) and [Ru(DIP)2(CBIP)](PF6)2 (CBIP = 2-(4′-chloro-1,1′-biphenyl-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline, Ru2) were synthesized. The cytotoxic activities in vitro of Ru1, Ru2 toward B16, A549, HepG2, SGC-7901, HeLa, BEL-7402, non-cancer LO2 were investigated using MTT method (3-(4,5-dimethylthiazole)-2,5-diphenltetraazolium bromide). Unexpectedly, Ru1, Ru2 can't prevent these cancer cells proliferation. To improve the anti-cancer effect, we used liposomes to entrap the complexes Ru1, Ru2 to form Ru1lipo, Ru2lipo. As expectation, Ru1lipo and Ru2lipo exhibit high anti-cancer efficacy, especially, Ru1lipo (IC50 3.4 ± 0.1 μM), Ru2lipo (IC50 3.5 ± 0.1 μM) display strong ability to block the cell proliferation in SGC-7901. The cell colony, wound healing, and cell cycle distribution show that the complexes can validly inhibit the cell growth at G2/M phase. Apoptotic studied with Annex V/PI doubling method showed that Ru1lipo and Ru2lipo can effectively induce apoptosis. Reactive oxygen species (ROS), malondialdehyde, glutathione and GPX4 demonstrate that Ru1lipo and Ru2lipo improve ROS and malondialdehyde levels, inhibit generation of glutathione, and finally result in a ferroptosis. Ru1lipo and Ru2lipo interact on the lysosomes and mitochondria and damage mitochondrial dysfunction. Additionally, Ru1lipo and Ru2lipo increase intracellular Ca2+ concentration and induce autophagy. The RNA-sequence and molecular docking were performed, the expression of Bcl-2 family was investigated by Western blot analysis. Antitumor in vivo experiments confirm that 1.23 mg/kg, 2.46 mg/kg of Ru1lipo possesses a high inhibitory rate of 53.53% and 72.90% to prevent tumor growth, hematoxylin-eosin (H&E) results show that Ru1lipo doesn't cause chronic organ damage and strongly promotes the necrosis of solid tumor. Taken together, we conclude that Ru1lipo and Ru2lipo cause cell death through the following pathways: autophagy, ferroptosis, ROS-regulated mitochondrial dysfunction, and blocking the PI3K/AKT/mTOR. Two new Ru(II) polypyridyl complexes [Ru(dip)2(BIP)](PF6)2 (dip = 4,7-diphenyl-1,10-phenanthrolie, BIP = 2-(1,1′-biphenyl-4-yl)-1H-imidazo[4,5-f] [1,10]phenanthroline, Ru1) and [Ru(dip)2(CBIP)](PF6)2 (CBIP = 2-(4′-chloro-1,1′-biphenyl-4-yl)-1H-imidazo[4,5-f] [1,10]phenanthroline, Ru2) and complexes-loaded liposomes Ru1lipo and Ru2lipo were synthesized and characterized. The cytotoxicity of the complexes Ru1, Ru2, Ru1lipo and Ru2lipo against B16, BEL-7402, A549, HepG2, SGC-7901 cancer cells and non-cancer cell LO2 was evaluated using 3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide (MTT) method. The high inhibitory rate in vivo of Ru1lipo inhibiting SGC-7901 tumor growth reaches 72.90%. [Display omitted] •Two new Ru(II) polypyridyl complexes were synthesized and characterized.•The cytotoxicity in vitro and in vivo of the complexes and liposomes was investigated.•Apoptosis, reactive oxygen species and cell cycle arrest were performed.•RNA-sequence assay was investigated.•The antitumor activity in vivo was investigated.