Effect of tamoxifen on lipoprotein(a) and insulin-like growth factor-I (IGF-I) in healthy women.
Studies in breast cancer patients have shown that tamoxifen decreases circulating levels of lipoprotein(a) (Lp(a)), an independent risk factor for premature coronary heart disease, and insulin-like growth factor-I (IGF-I), a promising surrogate biomarker for breast cancer. Since a common hormone regulatory pathway has been suggested for both biomarkers, we measured Lp(a) levels for 6 months in 68 healthy women participating in a chemoprevention trial of tamoxifen and correlated its changes with IGF-I. After 1 month, mean Lp(a) levels decreased by 23% with tamoxifen and increased by 6% with placebo (P = 0.033). No further change was observed after 2 and 6 months. Women with abnormal values at baseline (i.e. > 30 mg/dl) showed the highest reduction. The mean levels of IGF-I decreased by 23.5% with tamoxifen and remained stable with placebo, but the changes induced by tamoxifen in Lp(a) and IGF-I levels were uncorrelated. Our results support the observation that tamoxifen may be a suitable preventive option for women with multiple disease risk factors.
Decensi
A
A
FIRC Chemoprevention Unit, European Institute of Oncology, Milan, Italy. adecensi@ieo.it
Robertson
C
C
Ballardini
B
B
Paggi
D
D
Guerrieri-Gonzaga
A
A
Bonanni
B
B
Manetti
L
L
Johansson
H
H
Barreca
A
A
Bettega
D
D
Costa
A
A
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000517:prevention & control; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism; D015331:Cohort Studies; D004965:Estrogen Antagonists / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000187:drug effects* / Q000378:metabolism; D017270:Lipoprotein(a) / Q000187:drug effects* / Q000378:metabolism; D008875:Middle Aged; D013629:Tamoxifen / Q000494:pharmacology*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004965:Estrogen Antagonists; D017270:Lipoprotein(a); D013629:Tamoxifen; D007334:Insulin-Like Growth Factor I