title: Premetastatic vasculogenesis in oral squamous cell carcinoma xenograft-draining lymph nodes.
abstract: OBJECTIVE
  To study vascular anatomy on oral cancer-draining lymph nodes before metastasis in mice.
  
  
  METHODS
  Cell lines: highly lymph metastatic oral squamous cell carcinoma SASL1m and non-metastatic human adenoid cystic carcinoma ACC2. Bone marrow transplants and xenografts: Nude mice were lethally irradiated and transplanted with bone marrow cells from EGFP(+) mice. SASL1m or ACC2 cells were implanted in the tongue. Non-xenografted mice were used as controls. In addition, we injected conditioned medium from SASL1m or ACC2 in transplanted mice. Immunohistochemistry: Primary tumors and neck lymph nodes were resected and stained with anti-mouse Podoplanin and CD31. Images were visualized in a confocal microscope. Image analysis: Areas covered by EGFP, CD31 and Podoplanin were measured and compared statistically. Expression microarrays: Transcriptomic microarray analysis compared SASL1 to ACC2 cells. Interactomes were generated to reveal altered pathways.
  
  
  RESULTS
  SASL1m cells induced the assemblage of blood vessels in cancer-free, tumor-draining lymph nodes. These blood vessels incorporated bone marrow-derived EGFP(+)CD31(+) cells. Notably, SASL1m-conditioned medium induced a similar reaction. Non-metastatic cells failed to produce any change. Microarray and pathway analyses revealed the upregulation of Transforming Growth Factor-β, Lysyl Oxidase-like 2, Slit homolog 3 and Protease Serine 22. The upregulation of these genes was confirmed in xenografts.
  
  
  CONCLUSIONS
  This study suggests that a blood supply for new tumors is established in lymph nodes before metastasis. It also suggests that premetastatic vasculogenesis and primary tumor angiogenesis may be mediated by different mechanisms.
authors.affiliation: Department of Oral Maxillofacial Surgery, Ehime University Graduate School of Medicine, Toon, Ehime, Japan. guiliani@gmail.com
authors.forename: Alejandro E
authors.initials: AE
authors.lastname: Mayorca-Guiliani
authors.forename: Hajime
authors.initials: H
authors.lastname: Yano
authors.forename: Koh-Ichi
authors.initials: K
authors.lastname: Nakashiro
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hamakawa
authors.forename: Junya
authors.initials: J
authors.lastname: Tanaka
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D003528:Carcinoma, Adenoid Cystic / Q000098:blood supply* / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000098:blood supply* / Q000378:metabolism; D018450:Disease Progression; D006801:Humans; D008198:Lymph Nodes / Q000098:blood supply* / Q000378:metabolism; D008297:Male; D051379:Mice; D008819:Mice, Nude; D018613:Microscopy, Confocal; D009333:Neck; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000098:blood supply / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012468:Salivary Gland Neoplasms / Q000098:blood supply / Q000378:metabolism; D014062:Tongue Neoplasms / Q000098:blood supply* / Q000378:metabolism; D014183:Transplantation, Heterologous
chemical_list: D014408:Biomarkers, Tumor