I am pretty sure that there are COX-Inhibitors that are actually used for treating cancer. I remember reading, not to long ago, that a few scientists substituted a couple silicon atoms for carbon atoms in Indometacin and the new chemical was suprisingly less toxic and more effective at killing cancer cells (ecspecially pancreatic). It also said that Indometacin itself is used for cancer because, for reasons not yet clearly understood, it kills cancer cells. I read further into the use of NSAID for cancer and found that they cause greater expression of tumor supressor genes (Im not exactly sure myabe someone else can ellaborate more on the subject).