To test this notion, AGS cells, a gastric cancer cell line, were transduced with control (pLKO) or two independent knockdown constructs (sh4A#1, sh4A#2, sh4B#1, sh4B#2, sh4C#1, and sh4C#2) based on the lentivirus approach to deplete endogenous KDM4A, KDM4B, and KDM4C, respectively (Fig. 1a). Here, KDM4B is linked to gastric cancer.