An association between H3K4me3 and the tumor cells’ estrogen receptor status was observed: Positive estrogen receptor status was correlated with a higher IRS of the nuclear staining (p = 0.033, Rho = 0.147; Fig. 2a–c): the median of nuclear H3K4me3 expression in estrogen positive cells was 3, compared to 2 in estrogen negative cells. The gene discussed is ESR1; the disease is neoplasm.