title: Bone marrow-derived cells may not be the original cells for carcinogen-induced mouse gastrointestinal carcinomas.
abstract: OBJECTIVE
  It has been reported that bone marrow-derived cells (BMDC) can be original cells of mouse gastric cancers induced by Helicobacter felis (H. felis) infection. However, it is unknown whether BMDCs are also the original cells of mouse gastrointestinal cancers induced by gastric carcinogens N-nitroso-N-methylurea (NMU) and H. felis infection.
  
  
  METHODS
  C57BL/6 recipient mice were initially irradiated with 10Gy X-ray, reconstituted with bone marrow cells from the C57BL/6-Tg (CAG-EGFP) donor mice to label BMDCs with green fluorescence protein (GFP). After 4 weeks of recovery, the bone marrow-transplanted mice were given NMU in drinking water (240 ppm) and subsequently infected with H. felis by gavage. Eighty weeks later, all mice were euthanized for pathological examination. The BMDCs expressing GFP were detected in tissues using direct GFP fluorescence confocal microscopy analysis and immunohistochemistry staining (IHC) assays.
  
  
  RESULTS
  Neoplastic lesions were induced by NMU treatment and/or H. felis infection at the antrum of the glandular stomach and small intestine. In the direct GFP fluorescence confocal assay, GFP(+) epithelial cell cluster or glands were not observed in these gastrointestinal tumors, however, most GFP(+) BMDCs sporadically located in the tumor stromal tissues. Some of these GFP(+) stromal BMDCs co-expressed the hematopoietic marker CD45 or myofibroblasts markers αSMA and SRF. In the indirect GFP IHC assay, similar results were observed among 11 gastric intraepithelial neoplasia lesions and 2 small intestine tumors.
  
  
  CONCLUSIONS
  These results demonstrated that BMDCs might not be the source of gastrointestinal tumor cells induced by NMU and/or H. felis infection.
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Division of Etiology, Peking University Cancer Hospital & Institute, Haidian District, Beijing, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
authors.forename: Liankun
authors.initials: L
authors.lastname: Gu
authors.forename: Dajun
authors.initials: D
authors.lastname: Deng
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000473:pathology*; D002277:Carcinoma / Q000139:chemically induced* / Q000382:microbiology / Q000473:pathology*; D002478:Cells, Cultured; D005434:Flow Cytometry; D005770:Gastrointestinal Neoplasms / Q000139:chemically induced* / Q000382:microbiology / Q000473:pathology*; D044922:Helicobacter felis / Q000472:pathogenicity; D007150:Immunohistochemistry; D051379:Mice; D008810:Mice, Inbred C57BL; D009607:Nitrosourea Compounds / Q000633:toxicity
chemical_list: D009607:Nitrosourea Compounds