Abstract P2-10-30: Expression of lipid metabolism genes in contralateral unaffected breast associated with estrogen receptor status of breast cancer

Abstract

Abstract Background: Risk biomarkers that are specific to ER subtypes of breast cancer would help developing distinct prevention strategies. The contralateral unaffected breast of women with unilateral breast is a good model for defining subtype specific risk as women with ER− primary tumor are at high risk for subsequent ER− tumor in contralateral breast. Methods: We performed random fine needle aspiration of unaffected breast of cases. RNA samples from 30 subjects (15 ER+ and 15 ER−) were used for Ilumina expression array analysis. Findings were validated by qRT-PCR using independent sample set consisted of 36 subjects (12 ER+, 12 ER−, and 12 standard risk healthy controls). Results: Gene array studies identified 18 genes with significant higher expression in ER− case samples, 8 of which were associated with lipid metabolism. This pattern was confirmed by qRT-PCR in the same samples and in the 24 cases of validation set. When compared to the healthy controls, significant over-expression of 4 genes (DHRS2, HMGCS2, HPGD, ACSL3) was observed in ER− cases, with significant lower expression of UGT2B11 and APOD in ER+ cases, and decreased expression of UGT2B7 in both subtypes. Conclusion: Differential expression of lipid metabolism genes my be involved in the risk for subtypes of breast cancer, which might be potential biomarkers of ER specific breast cancer risk. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-30.