MCF7 cells exposed to contact culture, but not conditioned media, correlated with substantial lowering of a previously defined 49-gene signature for tumor cell dormancy (Figure 1B); low dormancy scores confer an approximately 2.1-fold increase in risk of recurrence in 4 independent cohorts of patients with ER+ breast cancers (P < 0.000005) (22). The gene discussed is ESR1; the disease is breast cancer.