title: PLEKHA5 as a Biomarker and Potential Mediator of Melanoma Brain Metastasis.
abstract: OBJECTIVE
  Approximately 40% of patients with metastatic melanoma develop brain metastases. Our purpose was to identify genes aberrantly expressed in melanoma that might be associated with propensity for brain homing.
  
  
  METHODS
  We studied gene expression profiles in a cell line model of brain metastasis (cerebrotropic A375Br cells vs. parental A375P cells) and compared them with profiles of patients who developed early brain metastases and who did not. A tissue microarray containing 169 metastatic melanoma cases with variable time to brain metastasis was constructed to further study marker expression by quantitative immunofluorescence. An in vitro model of the blood brain barrier (BBB) was generated to evaluate potential mediators of brain metastases.
  
  
  RESULTS
  PLEKHA5 was differentially expressed in both the A375 cell line model and patient samples subjected to gene expression profiling. At the protein level, by quantitative immunofluorescence, PLEKHA5 was associated with decreased brain metastasis-free survival. PLEKHA5 overexpression was not associated with other metastatic sites. Knockdown of PLEKHA5 decreases the viability of A375Br cells, inhibits BBB transmigration and invasion in vitro. Similar results were found with YUMUL cells, cultured from a patient with overwhelming brain metastases. PLEKHA5 knockdown did not affect the viability of A375P cells.
  
  
  CONCLUSIONS
  PLEKHA5 expression in melanoma tumors was associated with early development of brain metastases. Inhibition of PLEKHA5 might decrease passage across the BBB and decrease proliferation and survival of melanoma cells both in the brain and in extracerebral sites.
authors.affiliation: Department of Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Lucia B
authors.initials: LB
authors.lastname: Jilaveanu
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Fabio
authors.initials: F
authors.lastname: Parisi
authors.affiliation: Department of Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Meaghan L
authors.initials: ML
authors.lastname: Barr
authors.affiliation: Department of Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, Connecticut. Department of Biology, School of Health and Natural Sciences, University of Saint Joseph, West Hartford, Connecticut.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Zito
authors.affiliation: Department of Medical Biophysics, Sunnybrook Research Institute, Biological Sciences Platform, University of Toronto, Toronto, Ontario, Canada.
authors.forename: William
authors.initials: W
authors.lastname: Cruz-Munoz
authors.affiliation: Department of Medical Biophysics, Sunnybrook Research Institute, Biological Sciences Platform, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Kerbel
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: David L
authors.initials: DL
authors.lastname: Rimm
authors.affiliation: Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Marcus W
authors.initials: MW
authors.lastname: Bosenberg
authors.affiliation: Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Ruth
authors.initials: R
authors.lastname: Halaban
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Kluger
authors.affiliation: Department of Medicine, Section of Medical Oncology, Yale University School of Medicine, New Haven, Connecticut. harriet.kluger@yale.edu.
authors.forename: Harriet M
authors.initials: HM
authors.lastname: Kluger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics; D001932:Brain Neoplasms / Q000235:genetics* / Q000556:secondary*; D045744:Cell Line, Tumor; D005260:Female; D005455:Fluorescent Antibody Technique; D020869:Gene Expression Profiling; D006801:Humans; D007091:Image Processing, Computer-Assisted; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D008297:Male; D008545:Melanoma / Q000235:genetics* / Q000556:secondary*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D046888:Tissue Array Analysis; D059467:Transcriptome; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D047908:Intracellular Signaling Peptides and Proteins; C570565:PLEKHA5 protein, human