title: Association of galectin-3 expression with melanoma progression and prognosis.
abstract: OBJECTIVE
  Galectin-3 plays an important role in adhesion, proliferation, differentiation, angiogenesis and metastasis in multiple tumours. To investigate the role of galectin-3 in melanoma pathogenesis we examined the expression of galectin-3 in melanocytic lesions and analysed the correlation between galectin-3 expression and clinicopathologic factors including patient survival and BRAF mutation status.
  
  
  METHODS
  We evaluated the expression of galectin-3 in 53 cases of benign naevi, 31 cases of dysplastic naevi, 59 in-situ melanomas, 314 cases of primary melanoma and 69 metastatic melanomas using tissue microarray and immunohistochemistry.
  
  
  RESULTS
  Marked differences in expression of galectin-3 were seen between different categories of melanocytic lesions (ANOVA p<0.0001). An increase in expression of galectin-3 between benign naevi and thin primary melanomas and a progressive decrease in expression between thin primary melanomas and thicker melanomas or metastatic melanomas was seen. Strong galectin-3 expression was associated with improved overall survival (p=0.002 and p=0.0002 for cytoplasmic and nuclear expression, respectively) and melanoma-specific survival (p=0.017 and p=0.003 for cytoplasmic and nuclear expression, respectively). A multifactorial Cox regression analysis suggested that galectin-3 expression was an independent prognostic marker for overall survival in melanoma (risk ratio 0.73, 95% CI 0.547-0.970, p=0.031 for cytoplasmic expression and risk ratio 0.76, 95% CI 0.587-0.985, p=0.036 for nuclear expression). No association between galectin-3 expression and BRAF mutation status was observed.
  
  
  CONCLUSIONS
  This study suggests that galectin-3 is a marker of progression in melanocytic lesions and a novel prognostic marker in primary melanoma.
authors.affiliation: Edinburgh Cancer Centre, NHS Lothian, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK. Ewan.Brown@luht.scot.nhs.uk
authors.forename: Ewan R
authors.initials: ER
authors.lastname: Brown
authors.forename: Tamasin
authors.initials: T
authors.lastname: Doig
authors.forename: Niall
authors.initials: N
authors.lastname: Anderson
authors.forename: Thomas
authors.initials: T
authors.lastname: Brenn
authors.forename: Val
authors.initials: V
authors.lastname: Doherty
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.forename: John M S
authors.initials: JM
authors.lastname: Bartlett
authors.forename: John F
authors.initials: JF
authors.lastname: Smyth
authors.forename: David W
authors.initials: DW
authors.lastname: Melton
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D004252:DNA Mutational Analysis; D018450:Disease Progression; D005260:Female; D037502:Galectin 3 / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008545:Melanoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D046228:Microarray Analysis; D008875:Middle Aged; D009154:Mutation; D009363:Neoplasm Proteins / Q000378:metabolism*; D011379:Prognosis; D016016:Proportional Hazards Models; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D012307:Risk Factors; D012606:Scotland; D012878:Skin Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D016019:Survival Analysis
chemical_list: D037502:Galectin 3; D009363:Neoplasm Proteins; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf