Transcriptome profiling and proteomic validation reveals targets of the androgen receptor signaling in the BT474 breast cancer cell line

ABSTRACT: Accumulating evidence suggests that the androgen receptor (AR) and its endogenous ligands influence disease progression in breast cancer (BCa). However, AR-mediated changes in BCa differ among the various BCa subtypes according to their hormone receptor profile (i.e presence/absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2, (HER2)). Thus, we explored the androgen-regulated transcriptomic changes in the ER+PR+HER2+ BCa cell line, BT-474, and compared them with PR-mediated changes. Methods: We performed RNA sequencing analysis, in treated BT-474 cells with dihydrotestosterone (DHT) and progesterone (PROG). Validation of the top ten differentially androgen-regulated genes and a number of other genes found in enriched signaling pathways was performed by qRT-PCR in BT-474 and other BCa cell lines. A parallel reaction monitoring targeted proteomic approach was developed for the verification of selected transcripts at the protein level. Results: We detected 19,450 transcripts, of which 224 were differentially regulated after DHT treatment. The increased expression of two well-known androgen-regulated genes, KLK2 (p<0.05) and KLK3 (p<0.001), confirmed the successful androgen stimulation in BT-474 cells. The transcription factor, ZBTB16, was the most highly upregulated gene, with ~1000-fold change (p<0.001). Pathway enrichment analysis revealed downregulation of the DNA replication processes (p<0.05), and upregulation of the androgen signaling and fatty acid metabolism pathways (p<0.05). Changes related to PROG-treatment showed opposite effects in gene expression than DHT treatment. Similar expression profiles were observed among other BCa cell lines expressing high levels of AR (ZR75.1 and MBA-MB-453). The parallel reaction monitoring targeted proteomic analysis further confirmed that altered protein expression (e.g. KLK3, and ALOX15B) in the supernatant and cell lysate of DHT-treated BT-474 cells, compared to control cells. Discussion: Collectively, our findings suggest that AR modulates the metabolism of BT-474 cells by affecting expression of a large number of genes and proteins. Based on further pathway analysis, we suggest that AR acts as a tumor suppressor in BT-474 cells.

ORGANISM(S): Homo sapiens

PROVIDER: GSE197321 | GEO | 2022/02/26

REPOSITORIES: GEO