The functional and clinical significance of ROS-dependent downregulation of Sp TFs is supported by separate studies showing that knockdown of Sp1 or Sp3 and Sp4 (alone and in combination) decreased cancer cell growth, survival and migration/invasion, and tumor growth, mimicking the effects of ROS-inducing anticancer agents, in a mouse xenograft model [241,242]. This evidence concerns the gene SP1 and cancer.