this invention provides a method for inhibiting or preventing the abnormal growth of cells , including transformed cells , by administering an effective amount of o - acylated heparin derivative . abnormal growth of cells refers to cell growth independent of normal regulatory mechanism . this includes the abnormal growth of : tumor cells ; benign and malignant cells of other proliferative disease in which aberrant cellular proliferation occurs ; aberrant smooth muscle cell proliferation , such as might occur following treatment for coronary atherosclerosis such as angioplasty or the insertion of a stent into an occluded vessel .