MMP9 and neoplasm: Some of these proteins including cyclin D1, B-cell lymphoma 2 (Bcl-2), tumour necrosis factor α (TNF-α), vascular endothelial growth factor (VEGF), X-linked inhibitor apoptosis protein (XLAP), matrix metalloproteinase 9 (MMP 9) and cyclooxygenase 2 (COX-2) play an important role in determining the tumour biological behaviour and consequently the clinical course of the disease [18].