MMP2 and thoracic aortic aneurysm: Interestingly, very recently in a meta-analysis of thoracic aortic aneurysms the expression of MMP-2, MMP-9 and the relation of these proteinases to TIMP-1 and TIMP-2 were analyzed and it was found that thoracic aortic aneurysms with bicuspid aortic valves had a different expression pattern of MMPs and TIMPs compared to aortic aneurysms with tricuspid aortic valves (Rabkin, 2014).