To test whether ARHGEF16 regulates the malignancy of colon cancer cells, we used a lentiviral system to stably express ARHGEF16 in HCT116 and SW480 cells that contain relatively low levels of this protein and to silence ARHGEF16 expression in SW620 and HT29 cells because these cells have relatively high endogenous levels of ARHGEF16. The gene discussed is ARHGEF16; the disease is colonic neoplasm.