Time-resolved proteomic and phosphoproteomic profiling of Angiotensin-(1-7) signaling in A549 cells

Angiotensin-(1-7) [Ang-(1-7)] is a heptapeptide of the renin-angiotensin system (RAS) with antitumoral effects reported in various tumoral cell lines, including the human lung adenocarcinoma A549 lineage. While previous studies have shown that Ang-(1-7) modulates MAPK and PI3K-AKT signaling, the precise molecular mechanisms involved remain incompletely understood. To investigate the signaling events of Ang-(1-7) in lung cancer-derived cells, we employed an integrated proteomic and phosphoproteomic approach in A549 cells. We analyzed early (minutes) and late (hours) molecular responses to Ang-(1-7) treatment. The treatment resulted in time-dependent modulation of multiple signaling pathways, including significant alterations in the MAPK, PI3K-AKT, and mTOR pathways at both the protein and phosphorylation levels. Notably, widespread early dephosphorylation events were observed, similar to the effects seen with other RAS peptides with antitumoral effects. Additionally, Ang-(1-7) promoted a long-lasting nuclear accumulation (up to 24 h) of the transcription factor FOXO1 indicating its activation. FOXO1 is known to regulate genes involved in apoptosis, cell cycle arrest, and oxidative stress, suggesting a role in mediating the peptide's antitumoral effects. The study provides new insights into the molecular basis of Ang-(1-7)'s antitumoral activity in A549 cells and reinforce its therapeutic potential in lung cancer. Raw data are available via ProteomeXchange with identifier PXD066687. SIGNIFICANCE: This study provides the first comprehensive, time-resolved proteomic and phosphoproteomic analysis of Angiotensin-(1-7) signaling in the lung cancer cell line A549. By capturing both early and late molecular events in A549 cells, we reveal that Ang-(1-7) modulates critical pathways involved in tumor progression, including MAPK, PI3K-AKT, and mTOR signaling. Importantly, we demonstrate the nuclear accumulation of FOXO1, a key transcription factor associated with tumor suppression, as part of the Ang-(1-7) response in A549 cells.