title: 5-Fluorouracil combined with apigenin enhances anticancer activity through mitochondrial membrane potential (ΔΨm)-mediated apoptosis in hepatocellular carcinoma.
abstract: The development of chemoresistance may reduce the efficacy of chemotherapeutic drugs for treating hepatocellular carcinoma (HCC). In the present study, the effects of apigenin on intensifying the chemosensitivity of HCC cells and an HCC xenograft model in response to 5-fluorouracil (5-FU) were investigated. Sub-toxic concentrations of apigenin (4 μmol/L) significantly enhanced the cytotoxicity of 5-FU (100 μg/mL) in HCC cells. In vivo, combined treatment with apigenin (20 mg/kg, five times/week for 3 weeks) and 5-FU (20 mg/kg for 5 consecutive days) significantly inhibited the growth of HCC xenograft tumours. Annexin V-propidium iodide dual staining assays, terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling assays and western blotting analysis were used to confirm the synergistic effects of apigenin and 5-FU on HCC apoptosis. Coincubation of HCC cells with apigenin and 5-FU increased levels of reactive oxygen species (ROS), which was followed by a decrease in the mitochondrial membrane potential (ΔΨm). In addition, combined triggered the mitochondrial apoptotic pathway, as indicated by decreased Bcl-2 expression and loss of ΔΨm, with significant activation of caspase 3 and poly(ADP-ribose) polymerase. The present study is the first to demonstrate that apigenin may potentiate the cytotoxicity of 5-FU in HCC via inhibition of ROS-mediated drug resistance and concurrent activation of the mitochondrial pathways of apoptosis.
authors.affiliation: State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Xiao-Yun
authors.initials: XY
authors.lastname: Hu
authors.forename: Ji-Yun
authors.initials: JY
authors.lastname: Liang
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Guo
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Ya-Bing
authors.initials: YB
authors.lastname: Guo
mesh_terms: D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D047310:Apigenin / Q000008:administration & dosage; D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy* / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D004357:Drug Synergism; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D051379:Mice; D008819:Mice, Nude; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D047310:Apigenin; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3; D005472:Fluorouracil
keywords: 5-fluorouracil; apigenin; apoptosis; chemosensitivity; hepatocellular carcinoma