title: In Vivo Isolation of a Highly-aggressive Variant of Triple-negative Human Breast Cancer MDA-MB-231 Using Serial Orthotopic Transplantation.
abstract: OBJECTIVE
  We describe the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice.
  
  
  METHODS
  MDA-MB-231 cells expressing red fluorescent protein (RFP) (1×10(7) cells/site) were initially injected subcutaneously in the flank of nude mice. After the subcutaneous tumors grew, they were harvested and cut into small pieces for orthotopic implantation in the right lower mammary gland. After the orthotopic tumors grew, they were resected and cut into small pieces and orthotopically re-implanted into the mammary gland of nude mice. The tumors grew and metastasized to lymph nodes. The lymph node metastases were harvested and cut into small pieces and orthotopically re-implanted into the mammary gland of nude mice. After the orthotopic tumors grew, the tumor was removed leaving residual cancer cells, which grew and metastasized to lymph nodes. The lymph node metastases were harvested, cut into pieces and orthotopically re-implanted into the mammary gland of nude mice for two cycles and then isolated.
  
  
  RESULTS
  The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared to 2 of 12 of the parental cell line.
  
  
  CONCLUSIONS
  The availability of a highly invasive variant of TNBC targeting lymph nodes will be very useful for drug discovery of TNBC, a recalcitrant cancer and for mechanistic studies of its aggressiveness.
authors.affiliation: AntiCancer, Inc., San Diego, CA, U.S.A. Department of Surgery, University of California, San Diego, CA, U.S.A. Department of Gastroenterological Surgery, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Shuya
authors.initials: S
authors.lastname: Yano
authors.affiliation: AntiCancer, Inc., San Diego, CA, U.S.A. Department of Surgery, University of California, San Diego, CA, U.S.A. Department of Gastroenterological Surgery, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Kiyoto
authors.initials: K
authors.lastname: Takehara
authors.affiliation: AntiCancer, Inc., San Diego, CA, U.S.A. Department of Surgery, University of California, San Diego, CA, U.S.A.
authors.forename: Shinji
authors.initials: S
authors.lastname: Miwa
authors.affiliation: Department of Gastroenterological Surgery, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kishimoto
authors.affiliation: Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tazawa
authors.affiliation: Oncolys BioPharm Inc., Tokyo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Urata
authors.affiliation: Department of Gastroenterological Surgery, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kagawa
authors.affiliation: Department of Surgery, University of California, San Diego, CA, U.S.A.
authors.forename: Michael
authors.initials: M
authors.lastname: Bouvet
authors.affiliation: Department of Gastroenterological Surgery, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Toshiyoshi
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: AntiCancer, Inc., San Diego, CA, U.S.A. Department of Surgery, University of California, San Diego, CA, U.S.A. all@anticancer.com.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hoffman
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D051379:Mice; D064726:Triple Negative Breast Neoplasms / Q000473:pathology*; D023041:Xenograft Model Antitumor Assays
keywords: Breast cancer; MDA-MB-231; high metastasis variant; in vivo selection; lymph node; metastasis; nude mice; orthothopic transplantation; red fluorescent protein (RFP); triple negative