title: Evaluation of carcinoembryonic antigen mRNA in living, necrotic, and apoptotic gastric cancer cells by reverse transcriptase-polymerase chain reaction.
abstract: OBJECTIVE
  Positive mRNA expression of carcinoembryonic antigen (CEA) is often found in histologically negative lymph nodes, even in early gastric cancer. Therefore, we examined the differences in mRNA expression in MKN45 gastric cancer cells obtained under various cell conditions, namely, living cells, necrosis, and apoptosis, and assessed the possibility of detecting micrometastasis from these results.
  
  
  METHODS
  MKN45 cells were cultured with low-dose anticancer drugs (5-fluorouracil (5FU) + cisplatin (CDDP)) or cytokines (tumor necrosis factor alpha (TNFAlpha) + interferon gamma (INFGamma)) to induce apoptosis, or subjected to freezing-thawing to induce necrosis. All the treated cells were stained with propidium iodide and Hoechst and the numbers of living, apoptotic, and necrotic cells were counted. CEA mRNA expression was examined by reverse transcriptase-polymerase chain reaction (RT-PCR) and DNA fragmentation was confirmed.
  
  
  RESULTS
  mRNA expression of CEA and CEA/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) tended to decrease as the apoptotic index (AI) increased in the 5FU + CDDP group. On the other hand, almost no change was seen, even when the AI increased, in the TNFAlpha + IFNGamma group. mRNA expression in the necrotic cells was the almost same as that in the living cells.
  
  
  CONCLUSIONS
  Positive CEA mRNA expression by RT-PCR could suggest the existence of living cancer cells.
authors: Department of Tumor and General Surgery, Gifu University School of Medicine, 40 Tsukasa-machi, 500-8705, Gifu, Japan.
authors: Noriaki
authors: N
authors: Kojima
authors: Katsuyuki
authors: K
authors: Kunieda
authors: Koji
authors: K
authors: Matsui
authors: Hiroki
authors: H
authors: Kato
authors: Shigetoyo
authors: S
authors: Saji
mesh_terms: D017209:Apoptosis / Q000502:physiology*; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000032:analysis; D001707:Biopsy, Needle; D002272:Carcinoembryonic Antigen / Q000032:analysis*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008969:Molecular Sequence Data; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D012333:RNA, Messenger / Q000032:analysis; D012334:RNA, Neoplasm / Q000032:analysis*; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013274:Stomach Neoplasms / Q000473:pathology*; D014407:Tumor Cells, Cultured
chemical_list: D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen; D012333:RNA, Messenger; D012334:RNA, Neoplasm