Interestingly, it has been shown that quercetin can also attenuate the proliferation, invasion, and migration abilities of osteosarcoma by inhibiting parathyroid hormone receptor 1 and by simultaneously downregulating MMP-2 and MMP-9 and upregulating TIMP-1 and TIMP-2 at the mRNA level; this effect is both time- and concentration-dependent (20–100 μM) [89]. Here, MMP9 is linked to osteosarcoma.