title: [Experimental research on the mechanisms of human multiple myeloma LP-1 cell apoptosis induced by oridonin].
abstract: OBJECTIVE
  To explore the effects of oridonin (Ori) on human multiple myeloma (MM) cell line LP-1 apoptosis and its mechanisms.
  
  
  METHODS
  The human MM LP-1 cells were incubated in vitro by different concentrations of Ori. The proliferation activities of LP-1 cells were detected using MTT assay. The apoptosis rate of LP-1 cells was detected using Annexin V/PI double staining method. The ultrastructural changes of LP-1 cells were observed under transmission electron microscope (TEM) after they were treated with Ori. The mRNA expression of apoptosis correlated genes were detected using Real-time PCR.
  
  
  RESULTS
  Ori inhibited the proliferation of LP-1 cells in a dose- and time-dependent way. Results of Annexin V/PI double staining method showed that, along with increased drug concentration and prolonged drug action time, the apoptosis rate of LP-1 cells significantly increased. Under TEM, chromatin margination and mitochondrial swelling could be seen in LP-1 cells after they were treated by Ori. The mRNA expressions of PDCD5 and Bid were up-regulated, and those of Bcl-2 and NK-kappaB were down-regulated after action of Ori.
  
  
  CONCLUSIONS
  Ori induced cell apoptosis by up-regulating the mRNA expression of Bid and down-regulating the mRNA expression of Bcl-2 to decrease the mitochondrial membrane potential, trigger mitochondrial apoptosis way of LP-1 cells. Ori, also as the inhibitor of NF-kappaB activities, blocked the NF-kappaB activation, induced cell apoptosis, and inhibited the cell proliferation. Of them, it is necessary to further study the role of PDCD5 as an apoptosis promoter.
authors.affiliation: Department of Hematology, First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an 710061.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Mei
authors.initials: M
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D051023:BH3 Interacting Domain Death Agonist Protein / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D045786:Diterpenes, Kaurane / Q000494:pharmacology*; D006801:Humans; D009101:Multiple Myeloma / Q000473:pathology; D052002:NF-kappa B p50 Subunit / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D045786:Diterpenes, Kaurane; D052002:NF-kappa B p50 Subunit; C489548:NFKB1 protein, human; D009363:Neoplasm Proteins; C117283:PDCD5 protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; C011959:oridonin