title: Optical imaging of the peri-tumoral inflammatory response in breast cancer.
abstract: OBJECTIVE
  Peri-tumoral inflammation is a common tumor response that plays a central role in tumor invasion and metastasis, and inflammatory cell recruitment is essential to this process. The purpose of this study was to determine whether injected fluorescently-labeled monocytes accumulate within murine breast tumors and are visible with optical imaging.
  
  
  METHODS
  Murine monocytes were labeled with the fluorescent dye DiD and subsequently injected intravenously into 6 transgenic MMTV-PymT tumor-bearing mice and 6 FVB/n control mice without tumors. Optical imaging (OI) was performed before and after cell injection. Ratios of post-injection to pre-injection fluorescent signal intensity of the tumors (MMTV-PymT mice) and mammary tissue (FVB/n controls) were calculated and statistically compared.
  
  
  RESULTS
  MMTV-PymT breast tumors had an average post/pre signal intensity ratio of 1.8+/- 0.2 (range 1.1-2.7). Control mammary tissue had an average post/pre signal intensity ratio of 1.1 +/- 0.1 (range, 0.4 to 1.4). The p-value for the difference between the ratios was less than 0.05. Confocal fluorescence microscopy confirmed the presence of DiD-labeled cells within the breast tumors.
  
  
  CONCLUSIONS
  Murine monocytes accumulate at the site of breast cancer development in this transgenic model, providing evidence that peri-tumoral inflammatory cell recruitment can be evaluated non-invasively using optical imaging.
authors.affiliation: Department of Radiology and Biomedical Engineering, University of California, San Francisco, USA. asista@gmail.com
authors.forename: Akhilesh K
authors.initials: AK
authors.lastname: Sista
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Knebel
authors.forename: Sidhartha
authors.initials: S
authors.lastname: Tavri
authors.forename: Magnus
authors.initials: M
authors.lastname: Johansson
authors.forename: David G
authors.initials: DG
authors.lastname: DeNardo
authors.forename: Sophie E
authors.initials: SE
authors.lastname: Boddington
authors.forename: Sirish A
authors.initials: SA
authors.lastname: Kishore
authors.forename: Celina
authors.initials: C
authors.lastname: Ansari
authors.forename: Verena
authors.initials: V
authors.lastname: Reinhart
authors.forename: Fergus V
authors.initials: FV
authors.lastname: Coakley
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Coussens
authors.forename: Heike E
authors.initials: HE
authors.lastname: Daldrup-Link
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000276:immunology / Q000473:pathology*; D005260:Female; D005456:Fluorescent Dyes / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D008325:Mammary Neoplasms, Experimental / Q000276:immunology / Q000473:pathology*; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D018613:Microscopy, Confocal / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods*; D009000:Monocytes / Q000166:cytology / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes