SP4 and colonic neoplasm: For example, previous studies with NSAIDs show that tolfenamic acid induced proteasome-dependent degradation of Sp proteins in pancreatic cancer [38], the nitro-NSAID GT-094 induced ROS-dependent repression [25], and aspirin induced caspase-dependent degradation of Sp1, Sp3 and Sp4 in colon cancer cells and in a mouse xenograft [35].