Differential expression of cancer-related proteins in paired breast milk samples from women with breast cancer.
BACKGROUND
Breast cancer risk increases during pregnancy and remains elevated for a number of years thereafter. Cancer-associated proteins that are secreted into breast milk may provide a means to detect cancer in the lactating breast or to assess future breast cancer risk.


OBJECTIVE
To determine whether proteins linked to breast cancer would be differentially expressed in matched (both breasts from each participant) human milk samples collected from women with unilateral breast cancer.


METHODS
Five cancer-associated proteins (basic fibroblast growth factor [bFGF], YKL-40, neutrophil gelatinase-associated lipocalin, and transforming growth factor β1 and β2) were analyzed in milk provided by 5 lactating women, 4 of whom were known to have cancer in 1 breast (and the opposite breast clinically disease free) at the time of milk collection and 1 who developed breast cancer 2 years after milk collection.


RESULTS
Expression was significantly higher for TGFβ2 (P = .03) and bFGF (P =.03) in the breasts with cancer.


CONCLUSIONS
These proteins may play a role in assessing a woman's risk of pregnancy-associated breast cancer. Because of variable protein concentration among patients and the limited sample size, the results are considered preliminary.
University of Massachusetts at Amherst, Amherst, MA, USA.
Kathleen F
KF
Arcaro
Eva P
EP
Browne
Wenyi
W
Qin
Ke
K
Zhang
Douglas L
DL
Anderton
Edward R
ER
Sauter
D000209:Acute-Phase Proteins / Q000378:metabolism; D054392:Adipokines / Q000378:metabolism; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000378:metabolism*; D016022:Case-Control Studies; D000071451:Chitinase-3-Like Protein 1; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D006801:Humans; D007774:Lactation / Q000378:metabolism*; D037102:Lectins / Q000378:metabolism; D000071068:Lipocalin-2; D054834:Lipocalins / Q000378:metabolism; D008895:Milk, Human / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D018570:Risk Assessment; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D053781:Transforming Growth Factor beta2 / Q000378:metabolism
D000209:Acute-Phase Proteins; D054392:Adipokines; D014408:Biomarkers, Tumor; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; C489506:LCN2 protein, human; D037102:Lectins; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D053773:Transforming Growth Factor beta1; D053781:Transforming Growth Factor beta2; D016222:Fibroblast Growth Factor 2