BMP2 and cancer: In other studies, adverse effects have been reported due to poor growth factor control by the collagen-based sponge; for instance, in osteogenesis where collagen sponges are used as carriers of recombinant human Bone Morphogenetic Protein-2 (rhBMP-2), burst release and leakage in vivo can result in an unexpected local increase in BMP-2, which is linked to adverse effects, i.e., postoperative inflammation, ectopic bone formation, bone resorption, and at a low percentage, even cancer [96,97].