A nanoformulation that includes nanoparticles. Each nanoparticle includes a shell in which a glycosaminoglycan (GAG is encapsulated. The GAG is ionically or covalently bonded to the shell. The GAG is selected from the group consisting of sulfated non-anticoagulant heparin (SNACH), super-sulfated non-anticoagulant heparin (S-SNACH), and a combination thereof. The shell includes Poly (lactic-co-glycolic acid) (PLGA), Polyethylene Glycol (PEG)-PLGA, maleimide-PEG-PLGA, chitosan, chitosan-PLGA, methoxy-polyethyleneglycol-poly (lactide-co-glycolide) (MPEG-PLGA)-(maleimide-PEG-PLGA), PLGA-Polycaprolate, or calcium alginate. A method of using the nanoformulation to treat a cancer in a subject includes administering to the patient a therapeutically effective amount of the nanoformulation for treating the cancer.