title: Dietary suppression of the mammary CD29(hi)CD24(+) epithelial subpopulation and its cytokine/chemokine transcriptional signatures modifies mammary tumor risk in MMTV-Wnt1 transgenic mice.
abstract: Diet is highly linked to breast cancer risk, yet little is known about its influence on mammary epithelial populations with distinct regenerative and hence, tumorigenic potential. To investigate this, we evaluated the relative frequency of lineage-negative CD29(hi)CD24(+), CD29(lo)CD24(+) and CD29(hi)Thy1(+)CD24(+) epithelial subpopulations in pre-neoplastic mammary tissue of adult virgin MMTV-Wnt1-transgenic mice fed either control (Casein) or soy-based diets. We found that mammary epithelial cells exposed to soy diet exhibited a lower percentage of CD29(hi)CD24(+)Lin(-) population, decreased ability to form mammospheres in culture, lower mammary outgrowth potential when transplanted into cleared fat pads, and reduced appearance of tumor-initiating CD29(hi)Thy1(+)CD24(+) cells, than in those of control diet-fed mice. Diet had no comparable influence on the percentage of the CD29(lo)CD24(+)Lin(-) population. Global gene expression profiling of the CD29(hi)CD24(+)subpopulation revealed markedly altered expression of genes important to inflammation, cytokine and chemokine signaling, and proliferation. Soy-fed relative to casein-fed mice showed lower mammary tumor incidence, shorter tumor latency, and reduced systemic levels of estradiol 17-β, progesterone and interleukin-6. Our results provide evidence for the functional impact of diet on specific epithelial subpopulations that may relate to breast cancer risk and suggest that diet-regulated cues can be further explored for breast cancer risk assessment and prevention.
authors.affiliation: Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR, USA; Interdisciplinary Biomedical Sciences Program, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
authors.forename: Omar M
authors.initials: OM
authors.lastname: Rahal
authors.forename: Heather L
authors.initials: HL
authors.lastname: Machado
authors.forename: Maria Theresa E
authors.initials: MT
authors.lastname: Montales
authors.forename: John Mark P
authors.initials: JM
authors.lastname: Pabona
authors.forename: Melissa E
authors.initials: ME
authors.lastname: Heard
authors.forename: Shanmugam
authors.initials: S
authors.lastname: Nagarajan
authors.forename: Rosalia C M
authors.initials: RC
authors.lastname: Simmen
mesh_terms: D000818:Animals; D051927:CD24 Antigen / Q000378:metabolism*; D002478:Cells, Cultured; D018925:Chemokines / Q000235:genetics / Q000378:metabolism; D016207:Cytokines / Q000235:genetics* / Q000378:metabolism; D004032:Diet; D015536:Down-Regulation; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005260:Female; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism*; D008297:Male; D042361:Mammary Glands, Human / Q000378:metabolism; D015674:Mammary Neoplasms, Animal / Q000473:pathology* / Q000517:prevention & control; D051379:Mice; D008822:Mice, Transgenic; D011991:Receptors, Virus / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D012307:Risk Factors; D059467:Transcriptome; D051155:Wnt1 Protein / Q000172:deficiency / Q000235:genetics / Q000378:metabolism
chemical_list: D051927:CD24 Antigen; D018925:Chemokines; D016207:Cytokines; C111417:Fam89b protein, mouse; D019012:Integrin beta1; D011991:Receptors, Virus; D051155:Wnt1 Protein; C495246:Wnt1 protein, mouse