Immunohistochemical expression of matrix metalloproteinases in squamous cell carcinoma of the tongue and lower lip

Abstract Objective To evaluate the immunohistochemical expression of MMP-1, -2, -7, -9 and -26 in oral squamous cell carcinomas (SCCs) according to tumour site and histological grade of malignancy. Study design Fifteen cases of SCC of the lower lip and 15 cases of tongue SCC were selected and divided into low grade malignancy ( n = 17) and high grade malignancy ( n = 13). Results Higher immunohistochemical expression of MMPs by neoplastic cells was observed in tongue SCCs, with a statistically significant difference for MMP-9 ( P < 0.05). High-grade SCCs showed a higher expression of MMPs, except for MMP-2, with a statistically significant difference for MMP-7 ( P < 0.05) and MMP-26 ( P < 0.05). In addition, a direct association was observed between morphological scores of malignancy and MMP immunoreactivity, with the association being significant for MMP-7 and MMP-26. Conclusion The present results demonstrate the important role of MMPs in the development of SCCs of the lower lip and tongue.