KMT2D and small cell lung carcinoma: B-NHL KMT2DLOF cell lines also had significantly reduced levels of H3K4me2 compared to KMT2DWT cell lines (Welch’s t-test p-value < 0.05; Additional file 5: Fig. S1C), and both H3K4me1 and H3K4me2 levels trended lower in KMT2DLOF BLCA, SCLC, and UCEC cell lines, consistent with a reduction in KMT2D activity.