title: Pancreas duodenal homeobox-1 expression and significance in pancreatic cancer.
abstract: OBJECTIVE
  To study the correlations of Pancreas duodenal homeobox-1 with pancreatic cancer characteristics, including pathological grading, TNM grading, tumor metastasis and tumor cell proliferation.
  
  
  METHODS
  Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect PDX-1 mRNA expression in pancreatic cancer tissue and normal pancreatic tissue. The expression of PDX-1 protein was measured by Western blot and immunohistochemistry. Immunohistochemistry was also used to detect proliferative cell nuclear antigen (PCNA). Correlations of PDX-1 with pancreatic cancer characteristics, including pathological grading, TNM grading, tumor metastasis and tumor cell proliferation, were analyzed by using c2 test.
  
  
  RESULTS
  Immunohistochemistry showed that 41.1% of pancreatic cancers were positive for PDX-1 expression, but normal pancreatic tissue except islets showed no staining for PDX-1. In consistent with the result of imunohistochemistry, Western blot showed that 37.5% of pancreatic cancers were positive for PDX-1. RT-PCR showed that PDX-1 expression was significantly higher in pancreatic cancer tissues than normal pancreatic tissues (2(-3.56 +/- 0.35) vs 2(-8.76 +/- 0.14), P < 0.01). Lymph node metastasis (P < 0.01), TNM grading (P < 0.05), pathological grading (P < 0.05) and tumor cell proliferation (P < 0.01) were significantly correlated with PDX-1 expression levels.
  
  
  CONCLUSIONS
  PDX-1 is re-expressed in pancreatic cancer, and PDX-1-positive pancreatic cancer cells show more malignant potential compared to PDX-1-negative cells. Therefore, PDX-1-positive cells may be tumor stem cells and PDX-1 may act as alternate surface marker of pancreatic cancer stem cells.
authors.affiliation: Department of Pancreatic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.forename: Shan-Miao
authors.initials: SM
authors.lastname: Gou
authors.forename: Chun-You
authors.initials: CY
authors.lastname: Wang
authors.forename: He-Shui
authors.initials: HS
authors.lastname: Wu
authors.forename: Jiong-Xin
authors.initials: JX
authors.lastname: Xiong
authors.forename: Feng
authors.initials: F
authors.lastname: Zhou
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D005260:Female; D018398:Homeodomain Proteins / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D014411:Neoplastic Stem Cells / Q000378:metabolism / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D018398:Homeodomain Proteins; D015534:Trans-Activators; C084010:pancreatic and duodenal homeobox 1 protein