Identification of calreticulin as a prognosis marker and angiogenic regulator in human gastric cancer

Ann Surg Oncol. 2009 Feb;16(2):524-33. doi: 10.1245/s10434-008-0243-1. Epub 2008 Dec 3.

Abstract

The purpose of this study was to identify genes of interest for a subsequent functional and clinical cohort study using complementary (c)DNA microarrays. cDNA microarray hybridization was performed to identify differentially expressed genes between tumor and nontumor specimens in 30 gastric cancer patients. Subsequent functional studies of the selected gene were carried out, including cell cycle analysis, cell migration analysis, analyses of vascular endothelial growth factor (VEGF) and placenta growth factor (PlGF), and oligo-microarray studies using two pairs of stable cell lines of the selected gene. Another independent cohort study of 79 gastric cancer patients was conducted to evaluate the clinical significance of the selected gene in human gastric cancer. Calreticulin (CRT) was selected for further investigation. Two pairs of stable cell lines of CRT overexpression and CRT knockdown were constructed to perform functional studies. CRT enhanced gastric cancer cell proliferation and migration. Overexpressed CRT upregulated the expression and secretion of PlGF and VEGF. CRT had a reciprocal effect on connective tissue growth factor (CTGF) expression. Positive immunohistochemical staining of calreticulin was significantly correlated with high microvessel density (MVD) (p = 0.014), positive serosal invasion (p = 0.013), lymph node metastasis (p = 0.002), perineural invasion (p = 0.008), and poor patient survival (p = 0.0014). Multivariate survival analysis showed that CRT, MVD, and serosal invasion were independent prognosticators. We conclude that CRT overexpression enhances angiogenesis, and facilitates proliferation and migration of gastric cancer cells, which is in line with the association of CRT with MVD, tumor invasion, lymph node metastasis, and survival in gastric cancer patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers, Tumor / genetics
  • Biomarkers, Tumor / metabolism*
  • Blotting, Western
  • Calreticulin / genetics
  • Calreticulin / metabolism*
  • Cell Cycle
  • Cell Movement
  • Cell Proliferation
  • Cohort Studies
  • Connective Tissue Growth Factor / genetics
  • Connective Tissue Growth Factor / metabolism
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Gene Expression Profiling
  • Humans
  • Immunoenzyme Techniques
  • Lymphatic Metastasis
  • Male
  • Microcirculation
  • Middle Aged
  • Neoplasm Staging
  • Neovascularization, Pathologic / metabolism*
  • Oligonucleotide Array Sequence Analysis
  • Placenta Growth Factor
  • Pregnancy Proteins / genetics
  • Pregnancy Proteins / metabolism
  • Prognosis
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Stomach Neoplasms / blood supply*
  • Stomach Neoplasms / pathology
  • Survival Rate
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism

Substances

  • Biomarkers, Tumor
  • Calreticulin
  • PGF protein, human
  • Pregnancy Proteins
  • RNA, Messenger
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • Connective Tissue Growth Factor
  • Placenta Growth Factor