Limiting the analysis to the triples comprising the genes from the core of the IS-network, we identified HNRNPK, PANK3 and SMC4 gene triple as having the highest prognostic power for estrogen receptor-positive (ER-positive) breast cancer (with respect to the training and filtration datasets – see Methods, subsection Construction of prognostic gene signatures). The gene discussed is ESR1; the disease is breast cancer.