445 Inhibition of GPR30 Reveals Putative Genes Involved in the Pathogenesis of Inflammatory Breast Cancer

Abstract

OBJECTIVES/GOALS: Inflammatory Breast Cancer (IBC) is the most aggressive form of breast cancer and does not have targeted therapy. GPR30, a 7-transmembrane estrogen receptor, may play a role in regulating cell growth and proliferation of cancerous cells. Here, we evaluated changes in gene expression while inhibiting GPR30 to determine putative targets to treat IBC. METHODS/STUDY POPULATION: IBC cell lines (SUM149PT) were cultured in medium with serum stripped from growth factor and hormones for 48 hours. Cells were then exposed to either G15 (GPR30 inhibitor) at a concentration of 1µM or ETOH (vehicle negative control) 3 hours in triplicates. After exposure, total RNA was extracted using the Qiagen RNAeasy Mini kit and RNA was sequenced using the Illumina NextSeq (2 X 75bp). The higher-quality reads were aligned, annotated, and quantified to the human genome (HG38) using STAR and RSEM softwares. Gene expression analysis was performed in R statistical software (packages tximport and DESeq2). Functional and enrichment analyses were performed using Metascape and STRING database, respectively. RESULTS/ANTICIPATED RESULTS: There were 656 significantly expressed genes (p < 0.05) between groups (G15 vs. ETOH). The top 5 significant genes include: SMIM7, FANCG, ARID1A, MAML2, and ATF3. Significantly impacted biological processes and pathways include: electron transport chain, mitotic cell cycle process, microtubule cytoskeleton organization, cellular component morphogenesis and DNA-dependent DNA replication (adj p < 0.05). Additionally, physical and functional interaction networks showed 3 major clusters (≥ 12 genes), which contained several gene hubs including BRCA1, BRCA2, FOS (proto-oncogene), PLK1 and PAK1 (both serine/threonine-protein kinases), among others. Interestingly, the network analysis showed the previously known interaction between FANCG and BRCA2, which were both dysregulated by GPR30 inhibition. DISCUSSION/SIGNIFICANCE: Through gene expression, functional and enrichment analyses we found several targets genes that could be associated with the pathogenesis of IBC. Validation of candidates genes (qRT-PCR and Western blot), and functional assays (cell proliferation, motility, and invasion) will be performed to understand the potential of these genes in treating IBC.