Whole transcriptomic analysis of HR+ breast cancer in Black women classified as basal-type by BluePrint.

• DOI: 10.1200/jco.2022.40.16_suppl.517
• Publication Date: 2022-06-06T15:51:47Z
• Authors: Sonya A. Reid; Tuya Pal; Xiao-Ou Shu; Ann Tezak; Kent Hoskins; Dipali Sharma; Jennifer Wei; Yen Huynh; Josien Haan; Shiyu Wang; Andrea Menicucci; Patricia Dauer; M. William Audeh
• Keywords: Basal (medicine); Triple-negative breast cancer; Blueprint

517 Background: Breast cancer is the leading cause of cancer-associated death among Black women, and they are 41% more likely to die from breast compared White women. Few studies have evaluated if tumor biology differences contribute this disparity in outcomes. Similar triple negative (TNBC), hormone receptor-positive (HR+) tumors classified as Basal-Type with BluePrint genomic analysis (HR+/Basal) aggressive, higher grade, over-represented young women worse clinical TNBC associated low ACKR1 expression, which encodes Duffy antigen correlates Given over-representation outcomes HR+/Basal tumors, we differentially expressed genes (DEGs) by race subtype. Methods: This study includes 2657 Stage I-III who received testing participants ongoing BEST (5R01CA204819) at Vanderbilt University Medical Center or FLEX (NCT03053193). Of 455 315 had Luminal (HR+/Luminal) 140 Basal (66 74 HR-/Basal). within (n = 2202) were included a reference group HR+/Luminal 1825), 158), HR-/Basal 219) tumors. Two-tailed proportional z-test was used assess subtype proportion race. Limma R package perform differential gene expression (DGEA) whole transcriptome data. Significant DEGs an adjusted p-value < 0.05 absolute log2 fold change > 1. Results: significantly (15%; p 0.001) (16%; (7% 10%, respectively). In multidimensional scaling analysis, cluster rather than While DGEA comparing resulted over 700 no identified when TNBC. comparable (p 0.81) 0.46). contrast, lower 0.01) 0.01). Conclusions: racially diverse cohort, transcriptomic analyses suggest that biologically analogous TNBC, independent Molecular profiling racial disparities underscores need for representation trials. With evidence outcomes, these data patients should not be treated uniformly highlight importance further classification HR+ Clinical trial information: NCT03053193.