Detection of the expression of MMP-2 and MMP-9 by immunohistochemistry,gelatin zymography and Western blot analysis in salivary gland tumors

Objective To compare the merits and limitations of immunohistochemistry,Gelatin zymography and Western blot analysis in the detection of protein expression of MMP-2 and MMP-9 in salivary gland tumors.Methods Immunohistochemistry,Gelatin zymography and Western blot analysis were used in 8 malignant and 26 benign salivary gland tumors to carry out localization,semi-quantitative detection,quantitative detection and enzyme activity analysis for MMP-2 and MMP-9.Results Immunohistochemical method could locate and semi-quantitative detect the difference between matrix metalloproteinases in benign and malignant tumors.Western blot could quantitative describe the difference between matrix metalloproteinases in benign and malignant tumors.Zymography could detect differences between zymogen and active enzyme of MMP-2 and MMP-9 in benign and malignant tumors.Conclusion The combination of immunohistochemistry,Gelatin zymography and Western blot analysis can not only play the advantage of cellular localization by immunohistochemistry alone,but also overcome the weaknesses of inexact quantitative by immunohistochemistry and the limitations of non discernment of proenzyme and active enzyme,so as to reflect the actual expression of MMP-2 and MMP-9 in various types of tumor tissue more objectively and accurately.