A study has found that a class of molecules formed when the body metabolizes omega-3 fatty acids could inhibit the spreading and growth of cancer. In a recent study conducted at the University of Illinois researchers have found that in mices the molecules called endocannabinoids are made naturally by the body and have similar properties to cannabinoids found in marijuana - but without the psychotropic effects. In mice with tumors of osteosarcoma - a bone cancer that is notoriously painful and difficult to treat - endocannabinoids slowed the growth of tumors and blood vessels inhibited the cancer cells from migrating