Rat mammary extracellular matrix composition and response to ibuprofen treatment during postpartum involution by differential GeLC-MS/MS analysis.
Breast cancer patients diagnosed within five years following pregnancy have increased metastasis and decreased survival. A hallmark of postpartum biology that may contribute to this poor prognosis is mammary gland involution, involving massive epithelial cell death and dramatic stromal remodeling. Previous studies show pro-tumorigenic properties of extracellular matrix (ECM) isolated from rodent mammary glands undergoing postpartum involution. More recent work demonstrates systemic ibuprofen treatment during involution decreases its tumor-promotional nature. Utilizing a proteomics approach, we identified relative differences in the composition of mammary ECM isolated from nulliparous rats and those undergoing postpartum involution, with and without ibuprofen treatment. GeLC-MS/MS experiments resulted in 20327 peptide identifications that mapped to 884 proteins with a <0.02% false discovery rate. Label-free quantification yielded several ECM differences between nulliparous and involuting glands related to collagen-fiber organization, cell motility and attachment, and cytokine regulation. Increases in known pro-tumorigenic ECM proteins osteopontin, tenascin-C, and laminin-α1 and pro-inflammatory proteins STAT3 and CD68 further identify candidate mediators of breast cancer progression specific to the involution window. With postpartum ibuprofen treatment, decreases in tenascin-C and three laminin chains were revealed. Our data suggest novel ECM mediators of breast cancer progression and demonstrate a protective influence of ibuprofen on mammary ECM composition.
School of Medicine, Division of Medical Oncology, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, United States.
Jenean H
JH
O'Brien
Lauren A
LA
Vanderlinden
Pepper J
PJ
Schedin
Kirk C
KC
Hansen
D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D002478:Cells, Cultured; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D005260:Female; D007052:Ibuprofen / Q000494:pharmacology*; D007797:Laminin / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D049590:Postpartum Period / Q000378:metabolism* / Q000502:physiology; D060066:Protein Interaction Maps; D051381:Rats; D017207:Rats, Sprague-Dawley; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D016861:Cyclooxygenase Inhibitors; D016326:Extracellular Matrix Proteins; D007797:Laminin; D007052:Ibuprofen