title: Regulatory T lymphocytes are associated with less aggressive histologic features in microsatellite-unstable colorectal cancers.
abstract: BACKGROUND
  Colorectal cancers (CRCs) with microsatellite instability (MSI) are associated with a good prognosis and a high density of tumor-infiltrating lymphocytes (TILs). We have undertaken to determine the link between TIL densities and MSI CRC histologic features.
  
  
  METHODS
  Using tissue microarrays, T-cell sub-population infiltration, including T cells (CD3), cytotoxic T cells (CD8) and regulatory T cells (FoxP3) were studied in 86 MSI CRCs. We separately analyzed TILs of the stromal and epithelial compartments in the tumor center, the tumoral invasion margin and associated normal tissue.
  
  
  RESULTS
  For FoxP3+ TIL density in the tumor center stromal compartment, we found a strong negative correlation with T4 stage (p = 0.01), node invasion (p<0.001) and VELIPI (vascular emboli, lymphatic invasion and perinervous invasion) criteria (p = 0.002).
  
  
  CONCLUSIONS
  The strong correlation between regulatory T cell density and the absence of VELIPI criteria suggests that this sub-group of T cells is preferentially associated with less invasive tumors.
authors.affiliation: Inserm, U1079, Faculty of Medicine, Institute for Medical Research, Rouen University Hospital, Rouen, France. davidtougeron@hotmail.fr
authors.forename: David
authors.initials: D
authors.lastname: Tougeron
authors.forename: Pauline
authors.initials: P
authors.lastname: Maby
authors.forename: Nicolas
authors.initials: N
authors.lastname: Elie
authors.forename: Emilie
authors.initials: E
authors.lastname: Fauquembergue
authors.forename: Florence
authors.initials: F
authors.lastname: Le Pessot
authors.forename: Marie
authors.initials: M
authors.lastname: Cornic
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Sabourin
authors.forename: Pierre
authors.initials: P
authors.lastname: Michel
authors.forename: Thierry
authors.initials: T
authors.lastname: Frébourg
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Latouche
mesh_terms: D000368:Aged; D002452:Cell Count; D015179:Colorectal Neoplasms / Q000235:genetics / Q000276:immunology* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000276:immunology*