Fig. 2

Invasive breast cancer is associated with increased self-loops. a Number of significant epithelial-stromal co-expression interactions. The y-axis indicates the number of significant epithelial-stromal co-expression relationships (FDR < 5 %) for epithelial-stromal co-expression networks in normal breast, ER-negative IBC, and ER-positive IBC. b Proportion of self-loops among significant epithelial-stromal co-expression interactions. The y-axis indicates the proportion of significant relationships (FDR < 5 %) that are self-loop relationships in normal breast, ER-negative IBC, and ER-positive IBC. There is a significantly higher proportion of self-loop relationships among statistically significant interactions in IBC as compared with normal breast (p < 2.2e-16). c, d Proportion of self-loops and co-expression interaction significance in ER-positive IBC (c) and ER-negative IBC (d). The y-axis indicates the proportion of self-loop relationships among epithelial-stromal crosstalk interactions at progressive levels of statistical significance. The windows of statistical significance are indicated on the x-axis. There is a significant trend for a higher proportion of self-loops among the most significant co-expression relationships in ER-positive IBC (c) and ER-negative IBC (d) (both p < 2.2e-16). ER estrogen receptor; IBC invasive breast cancer; FDR false discovery rate