title: Human lung-derived mesenchymal stem cell-conditioned medium exerts in vitro antitumor effects in malignant pleural mesothelioma cell lines.
abstract: BACKGROUND
  The soluble factors secreted by mesenchymal stem cells are thought to either support or inhibit tumor growth. Herein, we investigated whether the human lung-derived mesenchymal stem cell-conditioned medium (hlMSC-CM) exerts antitumor activity in malignant pleural mesothelioma cell lines H28, H2052 and Meso4.
  
  
  METHODS
  hlMSC-CM was collected from the human lung-derived mesenchymal stem cells. Inhibition of tumor cell growth was based on the reduction of cell viability and inhibition of cell proliferation using the XTT and BrdU assays, respectively. Elimination of tumor spheroids was assessed by the anchorage-independent sphere formation assay. The cytokine profile of hlMSC-CM was determined by a chemiluminescence-based cytokine array.
  
  
  RESULTS
  Our data showed that hlMSC-CM contains a broad range of soluble factors which include: cytokines, chemokines, hormones, growth and angiogenic factors, matrix metalloproteinases, metalloproteinase inhibitors and cell-cell mediator proteins. The 48- and 72-hour hlMSC-CM treatments of H28, H2052 and Meso4 cell lines elicited significant decreases in cell viability and inhibited cell proliferation. The 72-hour hlMSC-CM incubation of H28 cells completely eliminated the drug-resistant sphere-forming cells, which is more potent than twice the half maximal inhibitory concentration of cisplatin.
  
  
  CONCLUSIONS
  Our findings indicate that the cell-free hlMSC-CM confers in vitro antitumor activities via soluble factors in the tested mesothelioma cells and, hence, may serve as a therapeutic tool to augment the current treatment strategies in malignant pleural mesothelioma.
authors: University Hospital Berne, Department of Clinical Research, Division of General Thoracic Surgery, Berne, Switzerland. cortes-dericks@gmx.de.
authors: Lourdes
authors: L
authors: Cortes-Dericks
authors: University Hospital Berne, Department of Clinical Research, Division of General Thoracic Surgery, Berne, Switzerland. laurene.froment@dkf.unibe.ch.
authors: Laurene
authors: L
authors: Froment
authors: University Hospital Berne, Department of Clinical Research, Division of General Thoracic Surgery, Berne, Switzerland. gregor.kocher@insel.ch.
authors: Gregor
authors: G
authors: Kocher
authors: University Hospital Berne, Department of Clinical Research, Division of General Thoracic Surgery, Berne, Switzerland. ralph.schmid@insel.ch.
authors: Ralph A
authors: RA
authors: Schmid
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002470:Cell Survival / Q000187:drug effects; D017077:Culture Media, Conditioned / Q000737:chemistry; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020128:Inhibitory Concentration 50; D008168:Lung / Q000473:pathology; D008175:Lung Neoplasms / Q000188:drug therapy*; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D008654:Mesothelioma / Q000188:drug therapy*; D000086002:Mesothelioma, Malignant; D010997:Pleural Neoplasms / Q000188:drug therapy*
chemical_list: D000970:Antineoplastic Agents; D017077:Culture Media, Conditioned