title: Pleiotrophin is a potential colorectal cancer prognostic factor that promotes VEGF expression and induces angiogenesis in colorectal cancer.
abstract: OBJECTIVE
  Pleiotrophin (PTN) is an important developmental secretory cytokine expressed in many types of cancer and involved in angiogenesis and tumor growth; however, the significance of PTN expression in colorectal cancer (CRC) has not been established.
  
  
  METHODS
  Immunohistochemistry, western blot, and enzyme-linked immunosorbent assay were used to detect PTN expression in CRC patients. The relationship between PTN expression and clinicopathological characteristics and survival time was statistically analyzed, and the relationship between PTN and vascular endothelial growth factor (VEGF) in tumor angiogenesis was further analyzed.
  
  
  RESULTS
  Of CRC tissues, 74.70% (62/83) stained positive, with a strong positive ratio of 60.24% (50/83). The expression of PTN in CRC tissues was much higher than in normal colorectal tissues. PTN serum levels in CRC patients (mean = 254.59 ± 261.76 pg/ml) were significantly higher than those of normal volunteers (mean = 115.23 ± 79.53 pg/ml; p < 0.001). PTN expression was related to CRC differentiation and TNM staging. High level of PTN is a predictor of a poor prognosis and high expression of PTN is accompanied by high expression of VEGF in CRC patients. Investigation of the relationship between PTN and VEGF revealed that PTN, through the PTN/RPTPβ/ζ signaling pathway, increased tyrosine phosphorylation of β-catenin, leading to an increase in VEGF.
  
  
  CONCLUSIONS
  Our study identifies PTN as an essential growth factor for CRC. PTN promotes VEGF expression and cooperates with VEGF in promoting CRC angiogenesis. PTN could serve as a prognostic factor for this cancer. Considering that PTN shows very limited expression in normal tissue, it may represent an attractive new target for CRC therapy.
authors: Department of Oncology, the First Affiliated Hospital, College of Medicine of Xi'an Jiaotong University, No. 277 Yanta West Road, Xi'an, Shaanxi, 710061, People's Republic of China. yingkong76@gmail.com
authors: Ying
authors: Y
authors: Kong
authors: Pei-Song
authors: PS
authors: Bai
authors: Ke-Jun
authors: KJ
authors: Nan
authors: Hong
authors: H
authors: Sun
authors: Nan-Zheng
authors: NZ
authors: Chen
authors: Xiao-Gai
authors: XG
authors: Qi
mesh_terms: D000230:Adenocarcinoma / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D018938:Caco-2 Cells; D002352:Carrier Proteins / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology; D002648:Child; D003106:Colon / Q000378:metabolism; D003110:Colonic Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D016207:Cytokines / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D012004:Rectal Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D012007:Rectum / Q000378:metabolism; D015398:Signal Transduction; D042461:Vascular Endothelial Growth Factor A / Q000097:blood / Q000187:drug effects / Q000378:metabolism*; D055815:Young Adult; D051176:beta Catenin / Q000187:drug effects / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D016207:Cytokines; D042461:Vascular Endothelial Growth Factor A; D051176:beta Catenin; C066845:pleiotrophin