NF-kappa B genes have a major role in Inflammatory Breast Cancer

We measured the mRNA expression levels of 60 NF-κB-related genes by using real-time quantitative RT-PCR in a well-defined series of 35 IBCs, by comparison with 22 stage IIB and III non inflammatory breast cancers. Twenty-four distant metastases of breast cancer served as "poor prognosis" breast tumor controls.Thirty-five (58%) of the 60 NF-κB-related genes were significantly upregulated in IBC compared with non IBC. The upregulated genes were NF-κB genes (NFKB1, RELA, IKBKG, NFKBIB, NFKB2, REL, CHUK), apoptosis genes (MCL1L, TNFAIP3/A20, GADD45B, FASLG, MCL1S, IER3L, TNFRSF10B/TRAILR2), immune response genes (CD40, CD48, TNFSF11/RANKL, TNFRSF11A/RANK, CCL2/MCP-1, CD40LG, IL15, GBP1), proliferation genes (CCND2, CCND3, CSF1R, CSF1, SOD2), tumor-promoting genes (CXCL12, SELE, TNC, VCAM1, ICAM1, PLAU/UPA) or angiogenesis genes (PTGS2/COX2, CXCL1/GRO1). Only two of these 35 genes (PTGS2/COX2 and CXCL1/GRO1)were also upregulated in breast cancer metastases. We identified a five-gene molecular signature that matched patient outcomes, consisting of IL8 and VEGF plus three NF-κB-unrelated genes that we had previously identified as prognostic markers in the same series of IBC.The NF-κB pathway appears to play a major role in IBC, possibly contributing to the unusual phenotype and aggressiveness of this form of breast cancer. Some upregulated NF-κB-related genes might serve as novel therapeutic targets in IBC.The main features distinguishing IBC (Inflammatory Breast Cancer) from other forms of primary breast cancer are a unique phenotype, which includes rapidly progressive breast inflammation, and an extreme tendency to metastasize. The three-year survival rate is about 40%, compared with 85% in non inflammatory breast cancer [1]. The molecular mechanisms underlying these characteristics are largely unknown, but their identification could help with diagnosis, patient stratification and drug development.We and others have described several molecular alterations in IBC, such as