Abstract 2534: The role of human 5-HTR2A in miRNA expression in the triple negative breast cancer cell line

In the United States, African American women are twice as likely to be diagnosed with triple-negative breast cancer (TNBC) than Caucasian women. African American women experience the highest death rates when diagnosed with breast cancer (Bca). TNBC is the most aggressive subtype of BCa and difficult to treat. Studies have demonstrated the expression of serotonin receptors (5-HTRs) on BCa cells and reported their role in tumor progression. The dysregulation of miRNAs has been associated with oncogenesis. miRNAs play a critical role in biological processes such as cell proliferation and death not only through targeting cell-cycle components but also by extensively regulating multiple signaling pathways. In the context of cancer, miRNAs have been observed to function as either oncogenes or tumor suppressors in cancer development. 5-Hydroxytryptamine receptor 2A (5-HTR2A), a G coupled-protein serotonin receptor, was implicated in cancer progression. In this study, we determined the miRNA expression profile related to 5-HTR2A biological activity in a TNBC cell line derived from an African American woman. The MDA-MB-468 cell line was cultured and an MTS assay performed to identify the effective concentration of (±)-DOI hydrochloride (5-HTR2A agonist) for treatment. Following treatment with 5 µM DOI, total RNA was isolated using Qiagen's AllPrep DNA/RNA Mini Kit following modified protocol for including miRNA. Total RNA was subjected to the NanoString human v3 miRNA kit targeting 800 endogenous miRNAs using color-coded probe sets. nSolver was used for differential miRNA expression and statistical analysis. For differential miRNA analysis DOI treated cells were compared with untreated MDA-MB 468 cells. The miRNA counts for each triplicate set were averaged. nSolver Analysis Software created by NanoString was used to determine fold change and statistical significance. Quality-control measures and normalization of data were also performed using the nSolver analysis package. After identifying significant (p