Adipokines in plasma and breast tissues: associations with breast cancer risk factors.
BACKGROUND
Blood adipokines are associated with breast cancer risk; however, blood-breast adipokine correlations and factors that explain variation in adipokines are unknown.


METHODS
Plasma (n = 155) and breast (n = 85) leptin and adiponectin were assessed by immunoassays in women with no history of cancer. Multivariable-adjusted regression models were used to determine breast adipokine associations.


RESULTS
Through body mass index (BMI)-adjusted analyses, we initially observed positive plasma-breast correlations for leptin (r = 0.41, P = 0.0002) and adiponectin (r = 0.23, P = 0.05). The positive plasma-breast correlation for leptin was strongest among normal weight women (r = 0.62), whereas the correlation for adiponectin was strongest among obese women (r = 0.31). In multivariable models, adjusting for BMI, demographic, reproductive, and lifestyle factors, plasma leptin was not associated with breast leptin, and only the highest quartile of plasma adiponectin was associated with tissue levels. Of the risk factors investigated, those that contributed most to the variation in breast tissue adipokines were BMI and race for leptin, oral contraceptive use and smoking status for adiponectin.


CONCLUSIONS
Although we report positive plasma-breast adipokine correlations overall, plasma adipokine concentrations may not be good surrogates for breast concentrations among all women. Predictors of breast adipokines vary, depending on subject characteristics, possibly explaining inconsistent epidemiologic results and they implicate differing pathways toward carcinogenesis.


CONCLUSIONS
A clearer understanding of the relationships between plasma adipokines and their levels within the target organ is necessary to better understand the impact of these hormones on breast cancer risk. Future studies are needed to identify additional factors associated with breast adipokines in target tissues.
Ohio State University Comprehensive Cancer Center, The Ohio State University, 300 W. 10th Avenue, Columbus, OH 43210, USA.
Adana A
AA
Llanos
Ramona G
RG
Dumitrescu
Catalin
C
Marian
Kepher H
KH
Makambi
Scott L
SL
Spear
Bhaskar V S
BV
Kallakury
David J
DJ
Perry
Rafael J
RJ
Convit
Mary E
ME
Platek
Amy E
AE
Millen
Lucile L
LL
Adams-Campbell
Jo L
JL
Freudenheim
Peter G
PG
Shields
D054392:Adipokines / Q000032:analysis* / Q000097:blood; D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001940:Breast / Q000737:chemistry*; D001943:Breast Neoplasms / Q000737:chemistry / Q000209:etiology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D012044:Regression Analysis; D012307:Risk Factors
D054392:Adipokines