title: Inhibition of autophagy by 3-methyladenine potentiates sulforaphane-induced cell death of BE(2)-C human neuroblastoma cells.
abstract: Sulforaphane (SFN) is an isothiocyanate present in cruciferous vegetables, which has been shown to exert an anti-cancer effect when tested in vitro and in vivo. The anti-cancer effects of SFN encompass induction of cytoprotective autophagy; therefore, the present study aimed to determine whether the chemopreventive activity of SFN may be potentiated by inhibition of autophagy. The present study provided detailed insight into the susceptibility of human neuroblastoma cells to treatment with synthetic SFN, in combination with an inhibitor of autophagy, 3-methyladenine (3-MA). The present study confirmed the suppression of the viability of the human neuroblastoma cell line BE(2)-C by SFN and reported the inhibition of DNA synthesis, as determined by a decrease in tritiated thymidine incorporation. Furthermore, the results verified the effectiveness of SFN in inducing apoptosis in the BE(2)-C cell line as demonstrated by caspase activation, increased protein expression levels of B-cell lymphoma 2-associated X protein and loss of mitochondrial membrane potential. Combined treatment of the cells with SFN with 3-MA proved to be effective in decreasing cell viability, through a mechanism that may proceed via the early induction of autophagy by SFN, followed by induction of apoptosis, as well as inhibition of autophagy by 3-MA.
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Irena
authors.initials: I
authors.lastname: Horwacik
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Gaik
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Durbas
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Boratyn
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Zając
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szychowska
authors.affiliation: Department of Biochemistry, University of Agriculture, Kraków 31‑425, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Szczodrak
authors.affiliation: Department of Inorganic Technology and Environmental Biotechnology, Cracow University of Technology, Kraków 31‑155, Poland.
authors.forename: Henryk
authors.initials: H
authors.lastname: Kołoczek
authors.affiliation: Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków 30‑387, Poland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Rokita
mesh_terms: D000225:Adenine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects* / Q000235:genetics; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D006801:Humans; D017879:Isothiocyanates / Q000008:administration & dosage; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009447:Neuroblastoma / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D017382:Reactive Oxygen Species / Q000378:metabolism; D013454:Sulfoxides
chemical_list: D017879:Isothiocyanates; D017382:Reactive Oxygen Species; D013454:Sulfoxides; C025946:3-methyladenine; C016766:sulforaphane; D000225:Adenine