Transcriptional program induced by factor VIIa-tissue factor, PAR1 and PAR2 in MDA-MB-231 cells

Area of Science:

• Biochemistry
• Molecular Biology
• Cellular Signaling

Background:

• Factor VIIa (FVIIa) binding to tissue factor (TF) initiates cell signaling through its protease activity and protease-activated receptor 2 (PAR2).
• Understanding the downstream gene expression changes induced by FVIIa is crucial for elucidating its biological functions.

Purpose of the Study:

• To compare the gene expression profiles induced by FVIIa with those induced by protease-activated receptor 1 (PAR1) and PAR2 agonists.
• To investigate the signaling pathways involved in FVIIa-mediated cellular responses in breast carcinoma cells.

Main Methods:

• Utilized MDA-MB-231 breast carcinoma cells, which constitutively express TF, PAR1, and PAR2.
• Analyzed gene-expression profiles following stimulation with FVIIa, PAR1 agonists, and PAR2 agonists.

Main Results:

• FVIIa stimulation differentially regulated 39 out of 8500 genes, many previously unrecognized.
• All FVIIa-regulated genes were also regulated by a PAR2 agonist, confirming FVIIa signaling via PAR2.
• A subset of PAR2-regulated genes was also modulated by a PAR1 agonist, indicating crosstalk between FVIIa/PAR2 and thrombin/PAR1 pathways.

Conclusions:

• FVIIa signaling primarily occurs through PAR2, influencing genes related to cytokines, chemokines, and growth factors.
• The gene repertoire induced by FVIIa suggests a role in wound healing responses.
• Observed differences in gene regulation between cell lines highlight context-dependent signaling mechanisms.