To confirm that the in vivo effects of GSK126 on NSCLC progression are on target, we performed immunohistochemistry (IHC) to detect histone H3K27 tri-methylation, the enzymatic product of Ezh2, and found significant depletion of this histone mark in the treated tumors compared with controls (Fig. 2, H and I). The gene discussed is EZH2; the disease is non-small cell lung carcinoma.