title: SPARCL1 expression increases with preoperative radiation therapy and predicts better survival in rectal cancer patients.
abstract: OBJECTIVE
  The secreted protein acidic and rich in cysteine-like 1 (SPARCL1) is expressed in various normal tissues and many types of cancers. The function of SPARCL1 and its relationship to a patient's prognosis have been studied, whereas its relationship to radiation therapy (RT) is not known. Our aim was to investigate the expression of SPARCL1 in rectal cancer patients who participated in a clinical trial of preoperative RT.
  
  
  METHODS
  The study included 136 rectal cancer patients who were randomized to undergo preoperative RT and surgery (n=63) or surgery alone (n=73). The expression levels of SPARCL1 in normal mucosa (n=29), primary tumor (n=136), and lymph node metastasis (n=35) were determined by immunohistochemistry.
  
  
  RESULTS
  Tumors with RT had stronger SPARCL1 expression than tumors without RT (P=.003). In the RT group, strong SPARCL1 expression was related to better survival than weak expression in patients with stage III tumors, independent of sex, age, differentiation, and margin status (P=.022; RR = 18.128; 95% confidence interval, 1.512-217.413). No such relationship was found in the non-RT group (P=.224). Further analysis of interactions among SPARCL1 expression, RT, and survival showed statistical significance (P=.024). In patients with metastases who received RT, strong SPARCL1 expression was related to better survival compared to weak expression (P=.041) but not in the non-RT group (P=.569).
  
  
  CONCLUSIONS
  SPARCL1 expression increases with RT and is related to better prognosis in rectal cancer patients with RT but not in patients without RT. This result may help us to select the patients best suited for preoperative RT.
authors.affiliation: Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, County Council of Östergötland, University of Linköping, Linköping, Sweden. Electronic address: angkotti@yahoo.gr.
authors.forename: Angeliki
authors.initials: A
authors.lastname: Kotti
authors.affiliation: Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, County Council of Östergötland, University of Linköping, Linköping, Sweden.
authors.forename: Annica
authors.initials: A
authors.lastname: Holmqvist
authors.affiliation: Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, County Council of Östergötland, University of Linköping, Linköping, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Albertsson
authors.affiliation: Division of Oncology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, County Council of Östergötland, University of Linköping, Linköping, Sweden. Electronic address: xiao-feng.sun@liu.se.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Sun
mesh_terms: D000368:Aged; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000528:radiation effects*; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D011379:Prognosis; D012004:Rectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000532:radiotherapy*; D012007:Rectum / Q000528:radiation effects; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; C503126:SPARCL1 protein, human