Apolipoprotein E genetic polymorphism, serum lipoproteins, and breast cancer risk

Abstract

Apolipoprotein E (apoE) is a polymorphic gene involved in lipid metabolism with three common variant alleles (epsilon2, epsilon3, and epsilon4). The epsilon4 allele has been associated with elevated levels of cholesterol as well as greater risk of coronary heart disease and Alzheimer's disease. In this case-control study we examined whether apoE genotype affected the association between serum lipids and breast cancer risk. In a subset of a study in western New York, 260 women with incident, primary breast cancer and 332 community controls were interviewed and provided blood samples. Polymerase chain reaction-restriction fragment length polymorphism analyses of the apoE polymorphism were performed. Participants were classified as apoE2 (epsilon2, epsilon2 or epsilon2, epsilon3), apoE3 (epsilon3, epsilon3), or apoE4 (epsilon4, epsilon4 or epsilon4, epsilon3). No unconditional logistic regression was used to compute adjusted odds ratios (ORs) and 95% confidence intervals (CI). Compared with women with the apoE3 genotype, there were no associations with risk for women with the apoE2 (OR=1.0; 95% CI=0. 91-1.64) or apoE4 genotype (OR=0.97; 95% CI=0.63-1.54). Higher serum levels of total cholesterol, HDL cholesterol, and LDL cholesterol were not associated with risk, either in the total sample or among subgroups of women defined by apoE genotype. Women with the highest serum triglyceride levels had an increase in risk (OR=1.63; 95% CI=1. 03-2.59) compared to women with the lowest levels. This effect was not apparent among women with the apoE2 or apoE3 genotype, but much stronger among women with the apoE4 genotype (OR=4.69; 95% CI=1. 49-14.7). These data suggest that the apoE4 genotype may modify the association between serum triglycerides and breast cancer risk.

Frontal gray matter reduction after breast cancer chemotherapy and association with executive symptoms: A replication and extension study

“…It was noteworthy that a relatively greater percentage of chemotherapy-treated patients were ε4 positive than in the other two groups. This is consistent with prior work showing an association between breast cancer and ε4 status (Chang et al, 2005; Moysich et al, 2000; Porrata-Doria et al, 2010), though other studies have failed to find such an effect (Chang et al, 2006; Niemi et al, 2000; Yaylim et al, 2003). By comparison, in a meta-analysis Farrer et al (1997) found that 25.7% of a group of 6262 Caucasian healthy older adults were APOE ε4 positive, in contrast to patients with Alzheimer’s disease, of whom 58.5% were APOE ε4 positive.…”

Serum Lipids and Tissue DNA Content in Egyptian Female Breast Cancer Patients

“…However, some researchers have found no association between the total serum cholesterol levels of premenopausal women and breast cancer risk (27). The non-significant change in total serum cholesterol levels of postmenopausal cases reported in the present study is consistent with reports of other studies (9,27,28). Several other case-control and prospective studies found that elevated total serum cholesterol levels is associated with increased breast cancer risk (25,26,(29)(30)(31)(32).…”

Apolipoprotein E genetic polymorphism, serum lipoprotein levels and breast cancer risk: A case-control study

“…Sample size was a limitation in this study, similar to other molecular epidemiological studies (5). Even having obtained a marginally higher e4 allelic frequency compared to that reported by other studies, the allelic frequencies of APOE were consistent with previous evidence (27).…”