C3 and breast cancer: In addition, the analysis of the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO) dataset on 51 human BC cell lines revealed the following signature of APP: SAA1/2 was highly expressed in both BL- and ML-TNBC; C3 and FN1 were predominantly expressed in BL-and ML-TNBC cells, respectively (Figure 1C and Supplementary Figure 1).