Several in vitro and in vivo studies found that THC and JWH-133, a CB2 agonist, exert anti-proliferative and anti-angiogenic effects on ErbB-2 breast cancer by reducing MMP-2 (Matrix metalloproteinase) and MMP-9 (Matrix Metalloproteinase-9) levels [29,30,31]. This evidence concerns the gene MMP9 and breast cancer.