title: Isoalantolactone induces autophagic cell death in SKOV₃ human ovarian carcinoma cells via upregulation of PEA-15.
abstract: We investigated the effects of isoalantolactone on cell growth inhibition and underlying cell death mechanisms in SKOV3 human ovarian cancer cells. The effects of isoalantolactone on cell proliferation and cell cycle were examined by EdU incorporation assay and DNA content assay. Western blotting was performed to determine the protein expression effects of isoalantolactone on cell cycle‑related proteins, autophagic regulators and PEA‑15. Autophagic vacuoles were observed by acridine orange staining. PEA‑15 knockdown by siRNA was used to confirm that PEA‑15 was involved in isoalantolactone‑induced autophagy of SKOV3 cells. Isoalantolactone inhibited the viability and proliferation of SKOV3 cells in a dose‑ and time‑dependent fashion. Isoalantolactone induced cell cycle arrest at G2/M phase and decreased the expression of cell cycle‑related proteins cyclin B1 and CDK1 in SKOV3 cells. Accordingly, isoalantolactone also induced SKOV3 cell autophagy via accumulation of autophagic vacuoles in the cytoplasm, increased Beclin1 protein expression, and increased LC3 cleavage. Furthermore, we observed that isoalantolactone‑induced autophagy was through increased PEA‑15 expression and the phosphorylation of ERK, whereas less change was observed to autophagy on SKOV3 cells through PEA‑15 knockdown by siRNA. Isoalantolactone‑induced autophagic cell death was further confirmed by pretreatment with the autophagy inhibitor 3‑methyladenine (3‑MA). In conclusion, isoalantolactone induced cell cycle arrest and autophagy and inhibited cell proliferation of SKOV3 cells via the upregulated PEA‑15 expression and the phosphorylation of ERK.
authors.affiliation: Department of Cell Biology, Liaoning Medical University, Jinzhou, Liaoning 121001, P.R. China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Weng
authors.affiliation: Department of Clinical Laboratory, Daqing Oilfield General Hospital, Daqing 163001, P.R. China.
authors.forename: Hongguo
authors.initials: H
authors.lastname: Gao
authors.affiliation: Educational Technologies and Simulation Training Centre, Naval University of Engineering Tianjin Campus, Tianjin 300450, P.R. China.
authors.forename: Jiehua
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Cell Biology, Liaoning Medical University, Jinzhou, Liaoning 121001, P.R. China.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Fan
authors.affiliation: Department of Clinical Laboratory, Daqing Oilfield General Hospital, Daqing 163001, P.R. China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Cell Biology, Liaoning Medical University, Jinzhou, Liaoning 121001, P.R. China.
authors.forename: Lihua
authors.initials: L
authors.lastname: Li
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D051017:Apoptosis Regulatory Proteins; D001343:Autophagy / Q000187:drug effects*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D055785:Gene Knockdown Techniques; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000096:biosynthesis*; D008810:Mice, Inbred C57BL; D010051:Ovarian Neoplasms / Q000473:pathology*; D010750:Phosphoproteins / Q000096:biosynthesis*; D034741:RNA, Small Interfering; D012717:Sesquiterpenes / Q000494:pharmacology*; D014162:Transfection; D015854:Up-Regulation; D023041:Xenograft Model Antitumor Assays
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D051017:Apoptosis Regulatory Proteins; D047908:Intracellular Signaling Peptides and Proteins; C092039:PEA15 protein, human; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D012717:Sesquiterpenes; C032787:isoalantolactone