Abstract P1-05-34: MicroRNAs as Prognostic Markers in Breast Cancer

Abstract

Abstract Background: Breast cancer (BC) is the most common cancer and the second leading cause of cancer death in American women. BC disproportionally affects women of ethnic minorities, especially Black and Hispanic. While this disparity has been acknowledged and social determinations of health remains an important contributor, BC pathophysiology is yet to be elucidated in minorities. MicroRNAs (miRNA), including but not limited to let-7, 125-3p, 192-5p, 451a, play regulatory roles in cancer pathobiology and progression in many cancer types, including but not limited to BC. In our lab, in vitro and in vivo studies on mouse models demonstrated that miR-23b and miR-27b had crucial roles in cancer progression in BC via mechanisms that involves nischarin, an integrin-binding protein, and were associated with worse outcome. Moreover, miRNAs can be detected and are stable in blood samples, and thus the detection has a profound clinical impact on diagnosis. Study Design: Between April 2021 and May 2022, 30 newly diagnosed patients with BC and 30 patients without any cancer diagnosis at University Medical Center- New Orleans were enrolled on the study (IRB# 936). 86% of patients are African American or Hispanics. Plasma samples were collected before any medical intervention for BC. Plasma miRNAs were isolated and miRNA expression were performed utilizing RT-PCR. Results: Expressions of let-7 and 125a miRNAs are two times higher in plasma of patients with BC compared to patients without a diagnosis of cancer. There was no difference in miRNA expression in circulatory 23b, 27b, 192-5p, and 451a. Among breast cancer types, there are two-fold decreased expression of 192-5p and 451a in triple negative compared to hormone positive BC. Conclusion: This project will add to the body of knowledge on roles of miRNAs as prognostic markers in patients with BC, more importantly, triple negative BC, and elucidate pathophysiologic mechanism contributing to racial disparity in breast cancer treatment and recurrence. In the near future, we aim to examine effects of chemotherapy and surgery on the expression of circulatory microRNAs. Citation Format: Anh Q. Nguyen, Colin Cunningham, Samuel Okpechi, Hassan Yousefi, Shawn McKinney, Brian Boulmay, Agustin Garcia, Suresh Alahari. MicroRNAs as Prognostic Markers in Breast Cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-05-34.