title: Nonlinear optical imaging to evaluate the impact of obesity on mammary gland and tumor stroma.
abstract: Obesity is an established risk factor for breast cancer incidence and mortality. However, the mechanism that links obesity to tumorigenesis is not well understood. Here we combined nonlinear optical imaging technologies with an early-onset diet-induced obesity breast cancer animal model to evaluate the impact of obesity on the composition of mammary gland and tumor stroma. Using coherent anti-Stokes Raman scattering and second harmonic generation on the same platform, we simultaneously imaged mammary adipocytes, blood capillaries, collagen fibrils, and tumor cells without any labeling. We observed that obesity increases the size of lipid droplets of adipocytes in mammary gland and collagen content in mammary tumor stroma, respectively. Such impacts of obesity on mammary gland and tumor stroma could not be analyzed using standard two-dimensional histologic evaluation. Given the importance of mammary stroma to the growth and migration of tumor cells, our observation provides the first imaging evidence that supports the relationship between obesity and breast cancer risk.
authors.affiliation: Weldon School of Biomedical Engineering, Department of Biological Sciences, Purdue Cancer Center, and Purdue Oncological Sciences Center, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Thuc T
authors.initials: TT
authors.lastname: Le
authors.forename: Charles W
authors.initials: CW
authors.lastname: Rehrer
authors.forename: Terry B
authors.initials: TB
authors.lastname: Huff
authors.forename: Maxine B
authors.initials: MB
authors.lastname: Nichols
authors.forename: Ignacio G
authors.initials: IG
authors.lastname: Camarillo
authors.forename: Ji-Xin
authors.initials: JX
authors.lastname: Cheng
mesh_terms: D017667:Adipocytes / Q000737:chemistry* / Q000473:pathology; D000818:Animals; D003094:Collagen / Q000032:analysis; D004032:Diet; D005260:Female; D008055:Lipids / Q000032:analysis; D008321:Mammary Glands, Animal / Q000737:chemistry* / Q000473:pathology; D008325:Mammary Neoplasms, Experimental / Q000737:chemistry* / Q000209:etiology / Q000473:pathology; D008856:Microscopy, Fluorescence / Q000379:methods*; D009765:Obesity / Q000150:complications*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013059:Spectrum Analysis, Raman / Q000379:methods*; D017154:Stromal Cells / Q000737:chemistry / Q000473:pathology
chemical_list: D008055:Lipids; D003094:Collagen