title: Sepia ink oligopeptide induces apoptosis in prostate cancer cell lines via caspase-3 activation and elevation of Bax/Bcl-2 ratio.
abstract: Sepia ink oligopeptide (SIO) is a tripeptide extracted from Sepia ink. To test the hypothesis that SIO inhibits prostate cancer by inducing apoptosis, the effects of SIO on the proliferation of three human prostate cancer cell lines were examined using a CCK-8 assay. SIO significantly inhibited the proliferation of DU-145, PC-3 and LNCaP cells in a time- and dose-dependent manner. Flow cytometry studies showed that exposing DU-145, PC-3 and LNCaP cells to 5, 10, or 15 mg/mL SIO for 24 h increased the percentage of the early-stage apoptotic cells from 11.84% to 38.26% (DU-145), 22.76% to 39.96% (PC-3) and 5.05% to 16.11% (LNCaP), respectively. In addition, typical morphologic changes were observed in the cells with acridine orange/ethidium bromide staining. SIO treatment induced strong S and G₂/M phase cell cycle arrest in a dose-dependent manner in DU-145 and LNCaP. In contrast, SIO treatment induced strong Sub G₁ and G₀/G₁ phase cell cycle arrest in a dose-dependent manner in PC-3. SIO exposure for 24 h decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the apoptogenic protein Bax. Moreover, the Bax/Bcl-2expression ratio was increased. Concurrently, the expression of caspase-3 was upregulated. These data support our hypothesis that SIO has anticarcinogenic properties.
authors.affiliation: School of Food science and Pharmacy, Zhejiang Provincial Key Engineering Technology Research Center of Marine Biomedical Products, Zhejiang Ocean University, Zhoushan 316000, China.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Huang
authors.affiliation: School of Food science and Pharmacy, Zhejiang Provincial Key Engineering Technology Research Center of Marine Biomedical Products, Zhejiang Ocean University, Zhoushan 316000, China.
authors.forename: Zuisu
authors.initials: Z
authors.lastname: Yang
authors.affiliation: School of Food science and Pharmacy, Zhejiang Provincial Key Engineering Technology Research Center of Marine Biomedical Products, Zhejiang Ocean University, Zhoushan 316000, China.
authors.forename: Di
authors.initials: D
authors.lastname: Yu
authors.affiliation: Zhijiang Hailisheng Group, Co., Ltd., Zhoushan 316000, China.
authors.forename: Jiabin
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Food science and Pharmacy, Zhejiang Provincial Key Engineering Technology Research Center of Marine Biomedical Products, Zhejiang Ocean University, Zhoushan 316000, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Li
authors.affiliation: School of Food science and Pharmacy, Zhejiang Provincial Key Engineering Technology Research Center of Marine Biomedical Products, Zhejiang Ocean University, Zhoushan 316000, China.
authors.forename: Guofang
authors.initials: G
authors.lastname: Ding
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004789:Enzyme Activation; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D008297:Male; D009842:Oligopeptides / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D049833:Sepia / Q000737:chemistry* / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; C494826:BAX protein, human; D009842:Oligopeptides; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D053148:Caspase 3