Significant reduction in breast cancer risk for Japanese women with interleukin 1B -31 CT/TT relative to CC genotype.
OBJECTIVE
The present case-control study aimed to examine the associations between breast cancer risk and three functional polymorphisms (Interleukin (IL) -1A C-889T, IL-1B C-31T and IL-1RN 86-bp variable number tandem repeat) related to expression of IL-1beta, which combines estrogen receptor.


METHODS
Cases were 231 patients with breast cancer who had been diagnosed 1 month to 6 years before their enrollment in 1999-2000 at Aichi Cancer Center Hospital. Controls were 186 non-cancer outpatients recruited during the same period at the digestive tract, breast surgery and gynecology clinics.


RESULTS
There were no differences in the genotype distributions of the IL-1A and IL-1RN polymorphisms, but individuals harboring a IL-1B C-31T T allele (high expression allele) were less frequent among cases (74.3%) than among controls (84.9%). The age-adjusted odds ratio (OR) relative to CC genotype was 0.52 (95% confidence interval, 0.30-0.88) for CT genotype, 0.58 (0.32-1.02) for TT genotype and 0.54 (0.33-0.90) for CT/TT genotype. Subgroup analysis showed that the preventive effect was significantly stronger for postmenopausal women than for premenopausal women (interaction 0.30, 0.11-0.84).


CONCLUSIONS
Although this is the first report on the association between breast cancer risk and IL-1B C-31T, the observed association seems plausible in a biological sense.
Ito
Lucy Sayuri
LS
Department of Neurology, School of Medicine, São Paulo University, São Paulo, Brazil.
Iwata
Hiroji
H
Hamajima
Nobuyuki
N
Saito
Toshiko
T
Matsuo
Keitaro
K
Mizutani
Mitsuhiro
M
Iwase
Takuji
T
Miura
Shigeto
S
Okuma
Katashi
K
Inoue
Manami
M
Hirose
Kaoru
K
Tajima
Kazuo
K
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005838:Genotype; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics*; D008875:Middle Aged; D018598:Minisatellite Repeats; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D017698:Postmenopause / Q000235:genetics; D017697:Premenopause / Q000235:genetics; D012306:Risk
D007375:Interleukin-1