title: Prokineticin 1 protein expression is a useful new prognostic factor for human sporadic colorectal cancer.
abstract: BACKGROUND
  Hematogenous metastasis, regarded as closely related to angiogenic growth factors, is associated with colorectal cancer prognosis. The angiogenic growth factor prokineticin 1 (PROK1) has been cloned from endocrine cells. However, its protein expression in human malignant tumors has not been studied. The current study established the anti-PROK1 monoclonal antibody (mAb) and examined the relationship between the expression of PROK1 protein and human colorectal cancer.
  
  
  METHODS
  The expression of PROK1 protein was assessed in 620 resected sporadic colorectal cancer tissue samples by immunohistochemical staining with in-house-developed human PROK1 mAb to investigate the relationship of PROK1 expression to clinicopathologic factors, recurrence, and survival rate and to evaluate its prognostic significance.
  
  
  RESULTS
  The expression of PROK1 protein was detected in 36 % (223/620) of human primary colorectal cancer lesions but no in the healthy mucosa adjacent to the colorectal cancer lesions. According to the clinicopathologic examinations, the frequency of positive PROK1 expression was significantly higher in cases with serosal invasion, lymphatic invasion, venous invasion, lymph node metastasis, liver metastasis, hematogenous metastasis, and higher stage disease. The recurrence rate and prognosis for patients with PROK1 expression-positive lesions were significantly worse. In the Cox proportional hazard model, PROK1 expression was an independent prognostic factor.
  
  
  CONCLUSIONS
  The expression of PROK1 protein was identified for the first time as a new prognostic factor in colorectal cancer.
authors.affiliation: First Department of Surgery, University of Fukui, Fukui, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nakazawa
authors.forename: Takanori
authors.initials: T
authors.lastname: Goi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Hirono
authors.forename: Akio
authors.initials: A
authors.lastname: Yamaguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000276:immunology; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D005768:Gastrointestinal Hormones / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D008113:Liver Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000556:secondary; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic; D010534:Peritoneal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000556:secondary; D011379:Prognosis; D015996:Survival Rate; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived / Q000378:metabolism*; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D005768:Gastrointestinal Hormones; C467610:PROK1 protein, human; D042662:Vascular Endothelial Growth Factor, Endocrine-Gland-Derived