Background: Lipid synthesis is an integrated result of genetic, epigenetic and environmental factors, and also can promote growth and survival of cancer cells. Apolipoprotein B plays a central role in lipid metabolism as the major protein component of very-low-density lipoprotein and low-density lipoprotein.
Methods: We investigated the associations of polymorphisms of rs693 (-7673C>T) and rs1042031 (-12669 G>A) in the APOB gene with risk of breast cancer in 675 blood-unrelated Chinese patients with breast cancer and 712 healthy controls.
Results: Polymorphisms of -12669 G>A and -7673C>T in the APOB gene were significantly associated with an increased risk of breast cancer (P = 0.000), especially for postmenopausal women (P = 0.000, 0.023). The positive associations still remained after further analysis of the two polymorphisms' distribution according to body mass index. However, no statistical associations were found between -12669 G>A and -7673C>T polymorphisms and other clinical characteristics, including tumor size, lymph node metastasis, histological grade, estrogen and progesterone receptor status and Her-2 status.
Conclusions: rs693 and rs1042031 polymorphisms in the APOB gene increased the risk of breast cancer in Chinese, and this role of the two polymorphisms in connection with breast cancer was not dependent on body mass index.