AIM:To investigate the expression of matrix metalloproteinase-2(MMP-2)and matrix metalloproteinase-14 (MMP-14) in retinoblastoma (Rb),and their relationships with tumor development stage.METHODS:Immunohistochemitry was used to detect the expression of MMP-2 and MMP-14 in 50 cases of paraffin embedded Rb samples.Quantitative analysis of the expression of MMP-2 and MMP-14 was assessed by HMIAS-2000 Color Pathologic Analysis System.The differences of the expression of MMP-2 and MMP-14 in each clinical and pathological stage were analyzed statistically.RESULTS:Positive expression rate of MMP-2 was 76% (38 cases)and of MMP-14 was 82%(41 cases).The expression of MMP-2 and MMP-14 was significantly higher in tumors with optic nerve invasion than in tumors without optic nerve invasion (P<0.01);the expression of MMP-2 and MMP-14 was significantly higher in tumors of extra-ocular stage than in tumors of glaucomatous stage or intra-ocular stage (P<0.01);There was a statistically significant positive correlation between the expression of MMP-2 and the expression of MMP-14 (P<0.01).CONCLUSION:MMP-2 and MMP-14 exist in retinoblastoma cells.The level of MMP-2 and MMP-14 is related to optic nerve invasion and clinical stage of Rb,which suggests the expression of MMP-2 and MMP-14 could be connected to the invasion and development of tumor cells.Further research is needed for deeper understanding of the biological behavior and better evaluation of the prognosis of Rb.