title: YKL-40 expression in soft-tissue sarcomas and atypical lipomatous tumors. An immunohistochemical study of 49 tumors.
abstract: OBJECTIVE
  YKL-40 is a glycoprotein that is expressed in many types of cancer cells. In some cancers, there is a correlation between high serum YKL-40 levels on the one hand and more aggressive disease and early death on the other. YKL-40 has never been studied in patients with soft-tissue sarcomas (STSs). We investigated whether YKL-40 is expressed in STS tissue and ascertained that the degree of expression is related to survival and/or the histological grade of the malignancy (FNCLCC).
  
  
  METHODS
  We included archived tissue from 49 patients (40 with STS and 9 with atypical lipomatous tumor, 20 female and 29 male, mean age 58 (4-89) years) who were treated with tumor resection in 2004 or 2005 at the Department of Orthopedics, Rigshospitalet. The minimum length of follow-up with respect to survival was 5-7 years. Immunohistochemical analysis with anti-YKL-40 antibody using tissue microarray was performed on resected tumors, and a semiquantitative measure of the intensity of YKL-40 staining was performed.
  
  
  RESULTS
  41 of the 49 tumors were positive for YKL-40, and of these, 36 had moderate to intense staining. 24 of the patients died within the follow-up period, and the intensity of YKL-40 staining was significantly higher in tumors from patients who had died in the follow-up period than in tumors from those who survived (p = 0.01). The staining intensity was different for the 3 grades of malignancy (p = 0.004): it was higher in highly malignant tumors (FNCLCC grade 2 and grade 3) than in low-malignancy tumors (grade 1).
  
  
  CONCLUSIONS
  YKL-40 is expressed in soft-tissue sarcomas. There is a correlation between expression of YKL-40 in STS and both histological grade of the malignancy and survival. Whether or not YKL-40 expression is an independent prognostic variable could not be determined in the present study.
authors.affiliation: Department of Orthopedic Surgery.
authors.forename: Mette L
authors.initials: ML
authors.lastname: Harving
authors.forename: Lise H
authors.initials: LH
authors.lastname: Christensen
authors.forename: Merete
authors.initials: M
authors.lastname: Ringsholt
authors.forename: Gunnar S
authors.initials: GS
authors.lastname: Lausten
authors.forename: Michael M
authors.initials: MM
authors.lastname: Petersen
mesh_terms: D054392:Adipokines / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D000071451:Chitinase-3-Like Protein 1; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D037102:Lectins / Q000378:metabolism*; D008067:Lipoma / Q000378:metabolism* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012509:Sarcoma / Q000378:metabolism* / Q000401:mortality; D012983:Soft Tissue Neoplasms / Q000378:metabolism* / Q000401:mortality; D055815:Young Adult
chemical_list: D054392:Adipokines; D014408:Biomarkers, Tumor; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D037102:Lectins