Dexamethasone as a Modulator of Renin–Angiotensin System Receptor Expression in Prostate and Ovarian Cancer Cells Under Standard and Low-Serum Conditions

Background/Objectives: Glucocorticoids, including dexamethasone (DEX), are known to demonstrate anti-inflammatory activity, suppress steroidogenesis, and mitigate the adverse effects of chemotherapy. They are therefore widely employed for managing solid malignancies. Emerging evidence indicates that DEX modulates both systemic and local renin–angiotensin system (RAS) activity, including genomic signaling via the glucocorticoid receptor (GR). Methods: DEX-dependent transcriptional responses for the angiotensin receptor genes (AGTR1, AGTR2, MAS1, and LNPEP) were evaluated in ovarian (SKOV3, KURAMOCHI) and prostate (DU-145, PC3) cancer cell lines. The cells were cultured under different serum conditions to determine the influence of nutrient availability on tumor progression. Results: DEX demonstrated distinct mechanisms of action between the ovarian and prostate cancer models. It was found to promote cancer cell survival through tissue-specific modulation of metabolic activity, clonogenic capacity, cell cycle distribution, and apoptotic responses. These effects were accompanied by condition-dependent alterations in angiotensin receptor gene expression. Hence, DEX may mediate the remodeling of local RAS signaling, which may be significant in overall survival and disease-free survival. The findings also indicate a previously-unreported NR3C1–LNPEP correlation, which was consistently observed across in vitro systems and patient datasets, in both ovarian- and prostate-derived cancer models. Conclusions: DEX appears to exert context-dependent regulation of RAS-associated gene networks in ovarian and prostate cancer, suggesting a role in tumor adaptive responses and potentially in therapeutic contexts.