Abstract 4253: Expression profiling of paired benign and breast cancer lesions in African American women

• Published in: Cancer research (Chicago, Ill.) Ill.), 2017-07, Vol.77 (13_Supplement), p.4253-4253
• Main Authors: Holowatyj, Andreana Natalie, Ruterbusch, Julie J., Ali-Fehmi, Rouba, Bandyopadhyay, Sudeshna, Mehner, Christine, Mann, Melody Stallings, Dyson, Gregory, Radisky, Derek, Cote, Michele L.
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM2017-4253

Benign breast disease, a known risk factor for subsequent breast cancer, includes a histological spectrum of lesions that can be subdivided based on the overall impression into non-proliferative lesions, proliferative lesions without atypia, and atypical hyperplasia. Yet little is known about the molecular characteristics of benign breast tissue from African American women, who suffer from disproportionately high breast cancer mortality rates. 72 breast samples from African American women were obtained. RNA was extracted from archival formalin-fixed, paraffin-embedded (FFPE) blocks. Gene expression profiling was performed on these samples using the Affymetrix HTA2.0 exon array chip. A fit linear model using generalized least squares identified probe sets with differential expression in benign-in situ and benign-invasive breast cancer paired lesions. 36 benign and 36 breast cancer paired lesions were included in the study. In the benign-in situ set (n=20), 978 probe sets were differentially expressed (threshold: fold-change, 1.50; p < 0.05). Probe sets mapped to 125 annotated genes, of which 69 (55.2%) were involved in cancer. The benign-invasive set (n=52) identified 351 differentially expressed probe sets that mapped to 84 annotated genes, of which 61 (72.6%) had known cancer significance. Genes involved in cellular growth and proliferation were significantly over-expressed in both benign-in situ and benign-invasive lesions (p-values < 0.0104). In the population of 36 paired samples, differentially expressed genes were found to regulate the estrogen receptor (ESR1) through distinct network associations. Many genes are differentially expressed by benign and breast cancer lesions, and in situ/invasive histology contribute to the distinct molecular characteristics and pathways of breast malignancy. Our findings highlight the first study to assess expression profiling of paired benign and breast cancer lesions among African American women. Citation Format: Andreana Natalie Holowatyj, Julie J. Ruterbusch, Rouba Ali-Fehmi, Sudeshna Bandyopadhyay, Christine Mehner, Melody Stallings Mann, Gregory Dyson, Derek Radisky, Michele L. Cote. Expression profiling of paired benign and breast cancer lesions in African American women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4253. doi:10.1158/1538-7445.AM2017-4253