title: IL-9 inhibits HTB-72 melanoma cell growth through upregulation of p21 and TRAIL.
abstract: BACKGROUND
  IL-9 is a pleiotropic cytokine produced mainly by Th9 cells. IL-9 may have an anti-proliferative role in murine melanoma, however, its effect on human melanoma is unknown.
  
  
  METHODS
  We examined the effects of IL-9 on proliferation and apoptosis in four human melanoma cell lines, HTB-65, HTB-72, CRL-11147, and SK-Mel-5. Clonogenic assay, PCNA staining, Quick Cell Proliferation assay, TUNEL staining and caspase-3 activity assay were used to assess proliferation and apoptosis, as appropriate.
  
  
  RESULTS
  We found that IL-9 decreased the percentage of colonies of HTB-72 and SK-Mel-5 cells but not that of HTB-65 or CRL-11147 cells. PCNA mRNA, PCNA+ cells, PCNA staining intensity, and the OD value of HTB-72 melanoma cells were consistently decreased in the present of IL-9. IL-9 also increased TUNEL+ cells and the relative caspase-3 activity in HTB-72 melanoma cells. We further investigated the possible molecular mechanisms using RT-PCR and immunohistochemical staining. The anti-proliferative effect of IL-9 on HTB-72 cells correlated with higher expression of anti-proliferative molecule p21. Its pro-apoptotic effect on HTB-72 cells correlated with higher expression of the pro-apoptotic molecule TRAIL.
  
  
  CONCLUSIONS
  IL-9 inhibits melanoma HTB-72 cell growth by upregulation of p21 and TRAIL. Understanding the interactions between IL-9 and melanoma may help direct strategies for cytokine-based immunotherapy development.
authors.affiliation: Department of Microbiology & Immunology, Des Moines University, Des Moines, Iowa.|Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.|Ellis Fischel Cancer Center, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Yujiang
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Microbiology & Immunology, Des Moines University, Des Moines, Iowa.|Department of Surgery, Luohu Hospital, Shenzhen, China.
authors.forename: Xuhui
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Qian
authors.initials: Q
authors.lastname: Bai
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.|Department of Gynecology & Obstetrics, Luohu Hospital, Shenzhen, China.
authors.forename: Chenglu
authors.initials: C
authors.lastname: Qin
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Abdimalik O
authors.initials: AO
authors.lastname: Mohamud
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Ziwen
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Tyler W
authors.initials: TW
authors.lastname: Ball
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Caleb M
authors.initials: CM
authors.lastname: Ruth
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Dylan R
authors.initials: DR
authors.lastname: Newcomer
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Herrick
authors.affiliation: Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.|Ellis Fischel Cancer Center, University of Missouri School of Medicine, Columbia, Missouri.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Nicholl
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism*; D006131:Growth Inhibitors / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D016906:Interleukin-9 / Q000378:metabolism* / Q000494:pharmacology; D008545:Melanoma / Q000188:drug therapy*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D006131:Growth Inhibitors; D016906:Interleukin-9; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human
keywords: IL-9; apoptosis; melanoma cells; proliferation