IRF-1 plays a role in this growth suppression as shown by significant resistance to growth suppression in a breast cancer cell line stably transfected with short hairpin RNA against IRF-1.
To assess the association of IRF1 mRNA expression with clinical outcomes in breast cancer, we studied data from two published gene expression microarray datasets.
These observations support the exploration of clinical trials combining antiestrogens and compounds that can induce IRF1, such as IFNgamma, for the treatment of some ER-positive breast cancers.
We now report that the A4396G single nucleotide polymorphism in the IRF1 gene is more frequent in human breast cancer cell lines than in the general population (P = 0.01).
We have used a dual approach, measuring whether overexpression of wild-type IRF-1 or a dominant negative IRF-1 (dnIRF-1) produce opposing effects on breast cancer cell proliferation in vitro or tumorigenicity in athymic nude mice.