title: Intratumoral heterogeneity of CD44v6 in rectal cancer.
abstract: OBJECTIVE
  CD44v6 plays a controversial role in tumor progression and patient outcome in colorectal cancer by plenty of conflicting reports. The purpose of this study was to profile the intratumoral heterogeneity of CD44v6 in rectal cancer and investigate its role in lymph node metastasis.
  
  
  METHODS
  Sixty patients were included in this study. Immunohistochemistry for CD44v6 was performed in normal mucosa, primary tumor, and lymph node metastasis with whole tissue sections. The staining intensity in tumor center and invasive front was separately measured. Sampling bias was evaluated by quantitative real-time PCR with 15 pairs of frozen tissues from different sites of the primary tumor.
  
  
  RESULTS
  CD44v6 expression increased from normal mucosa to primary tumor to lymph node metastasis. Multiple intratumoral staining patterns was observed in primary tumor, and CD44v6 expression in invasive front was significantly higher than that in tumor center. In addition, mRNA expression levels differed across different geographical regions of the tumor. No association between CD44v6 expression and lymph node metastasis was revealed.
  
  
  CONCLUSIONS
  Substantial intratumoral heterogeneity of CD44v6 exists in rectal cancer that impacts the outcome of individual studies. CD44v6 expression should be assessed in a more precise way with a specified staining pattern and in a designated location.
authors.affiliation: Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou Road No. 1838, Guangzhou, 510515, China.|Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Shatai Road No. 1023, Guangzhou, 510515, China.|Department of Surgical Oncology, The First Affiliated Hospital of Wenzhou Medical University, Fuxue Road No. 2, Wenzhou, 325000, China.
authors.forename: H-G
authors.initials: HG
authors.lastname: Liu
authors.affiliation: Department of Surgical Oncology, The First Affiliated Hospital of Wenzhou Medical University, Fuxue Road No. 2, Wenzhou, 325000, China.
authors.forename: L
authors.initials: L
authors.lastname: Lv
authors.affiliation: Department of Pathology, Nanfang Hospital, Southern Medical University, Guangzhou Road No. 1838, Guangzhou, 510515, China. shenhong2010168@163.com.|Department of Pathology, School of Basic Medical Sciences, Southern Medical University, Shatai Road No. 1023, Guangzhou, 510515, China. shenhong2010168@163.com.
authors.forename: H
authors.initials: H
authors.lastname: Shen
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000556:secondary*; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018960:Hyaluronan Receptors / Q000235:genetics / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000378:metabolism* / Q000473:pathology; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012004:Rectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; C112697:CD44v6 antigen; D018960:Hyaluronan Receptors; D012333:RNA, Messenger
keywords: CD44v6; Intratumoral heterogeneity; Metastasis; Rectal cancer