title: Targeting survivin with prodigiosin isolated from cell wall of Serratia marcescens induces apoptosis in hepatocellular carcinoma cells.
abstract: BACKGROUND
  Abnormal activation of the Wnt/β-catenin signaling pathway increases survivin expression that is involved in hepatocarcinogenesis. Therefore, downregulation of survivin may provide an attractive strategy for treatment of hepatocellular carcinoma. In this regard, little is known about the anticancer effects of prodigiosin isolated from cell wall of Serratia marcescens on the survivin expression and induction of apoptosis in hepatocellular carcinoma cells.
  
  
  METHODS
  Human hepatocellular carcinoma (HepG2) cells were treated with 100-, 200-, 400-, and 600-nM prodigiosin after which morphology of cells, cell number, growth inhibition, survivin expression, caspase-3 activation, and apoptotic rate were evaluated by inverted microscope, hemocytometer, MTT assay, RT-PCR, fluorometric immunosorbent enzyme assay, and flow cytometric analysis, respectively.
  
  
  RESULTS
  Prodigiosin changed morphology of cells to apoptotic forms and disrupted cell connections. This compound significantly increased growth inhibition rate and decreased metabolic activity of HepG2 cells in a dose- and time-dependent manner. After 24-, 48-, and 72-h treatments with prodigiosin at concentrations ranging from 100 nM to 600 nM, growth inhibition rates were measured to be 1.5-10%, 24-47.5%, and 55.5-72.5%, respectively, compared to untreated cells. At the same conditions, metabolic activities were measured to be 91-83%, 74-53%, and 47-31% for indicated concentrations of prodigiosin, respectively, compared to untreated cells. We also found that treatment of HepG2 cells for 48 h decreased significantly cell number and survivin expression and increased caspase-3 activation in a dose-dependent manner. Specifically, treatment with 600-nM prodigiosin resulted in 77% decrease in cell number, 88.5% decrease in survivin messenger RNA level, and 330% increase in caspase-3 activation level compared to untreated cells. An increase in the number of apoptotic cells (late apoptosis) ranging from 36.9% to 97.4% was observed with increasing prodigiosin concentrations.
  
  
  CONCLUSIONS
  From our data, prodigiosin is an attractive compound that turns the profile of high-level survivin expression in hepatocellular carcinoma cells into that of normal cells and may provide a novel approach to the hepatocellular carcinoma-targeted therapy.
authors.affiliation: 1 Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Islamic Republic of Iran.
authors.forename: R A
authors.initials: RA
authors.lastname: Yenkejeh
authors.affiliation: 1 Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Islamic Republic of Iran.|2 Department of Histology and Embryology, Faculty of Science, Urmia University, Urmia, Islamic Republic of Iran.
authors.forename: M R
authors.initials: MR
authors.lastname: Sam
authors.affiliation: 1 Department of Cellular and Molecular Biotechnology, Institute of Biotechnology, Urmia University, Urmia, Islamic Republic of Iran.
authors.forename: M
authors.initials: M
authors.lastname: Esmaeillou
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism; D002452:Cell Count; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002473:Cell Wall / Q000737:chemistry; D056945:Hep G2 Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000235:genetics*; D008113:Liver Neoplasms / Q000378:metabolism; D011353:Prodigiosin / Q000302:isolation & purification / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D012706:Serratia marcescens; D000077022:Survivin
chemical_list: D000970:Antineoplastic Agents; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D012333:RNA, Messenger; D000077022:Survivin; D053148:Caspase 3; D011353:Prodigiosin
keywords: Apoptosis; Serratia marcescens; caspase-3; hepatocellular carcinoma; prodigiosin; survivin