title: Characterization of mast cell subpopulations in lip cancer.
abstract: BACKGROUND
  Lip squamous cell carcinoma (SCC) is the most common form of oral cancer. Human mast cells (MCs), which are increased in lip SCC, are classified by their protease content in tryptase-positive (MC(T)) and tryptase/chymase-positive (MC(TC)). MC proteases are associated with tumor progression and angiogenesis. The aim of this study was to quantify and characterize MC subpopulations in lip SCC.
  
  
  METHODS
  Serial sections from lip SCC (n = 21) and normal lip vermilion (n = 8) biopsies were stained immunohistochemically for tryptase and enzymehistochemically for chymase to determine MC subpopulation density and distribution.
  
  
  RESULTS
  MC(T) and MC(TC) were increased in lip SCC when compared with normal lip (P < 0.0001), where MC(T) predominated over MC(TC) (P < 0.01). In lip SCC neither subpopulation predominated. Regarding distribution, MC(T) were higher than MC(TC) at the intratumoral stroma, whereas MC(TC) were higher than MC(T) at the peritumoral stroma (P < 0.01).
  
  
  CONCLUSIONS
  The results suggest that MC subpopulations may contribute to lip SCC progression. While intratumoral MC(T) may stimulate angiogenesis, peritumoral MC(TC) may promote extracellular matrix degradation and tumor progression at the invasion front.
authors.affiliation: Department of Oral Surgery, College of Dentistry, Universidad de Concepción, Casilla 160 C, Concepcion, Chile. grojas@udec.cl
authors.forename: I G
authors.initials: IG
authors.lastname: Rojas
authors.forename: M L
authors.initials: ML
authors.lastname: Spencer
authors.forename: A
authors.initials: A
authors.lastname: Martínez
authors.forename: M A
authors.initials: MA
authors.lastname: Maurelia
authors.forename: M I
authors.initials: MI
authors.lastname: Rudolph
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000473:pathology*; D015550:Cell Degranulation; D053818:Chymases; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008048:Lip Neoplasms / Q000201:enzymology / Q000473:pathology*; D008297:Male; D008407:Mast Cells / Q000201:enzymology*; D008875:Middle Aged; D012697:Serine Endopeptidases / Q000032:analysis / Q000378:metabolism*; D018709:Statistics, Nonparametric; D053802:Tryptases
chemical_list: D012697:Serine Endopeptidases; D053818:Chymases; D053802:Tryptases