Immunohistochemical study of p53, Ki-67, MMP-2 and MMP-9 expression at invasive front of squamous cell and verrucous carcinoma in oral cavity.

Squamous cell carcinoma (SCC) is the most common malignancy in the oral cavity. Verrucous carcinoma (VC) is a lower grade subtype of SCC with pathological similarities but different management. Tumor invasive front (TIF) is a dynamic location in the differentiation of malignancies. p53 is a tumor suppressor and Ki-67 a proliferation marker. Matrix metalloproteinases 2 and 9 are involved in the tumor invasiveness. We assessed these markers in TIF of oral SCC and VC to find more precise grading scales. We studied the expression of markers in the invasive front of 42 cases of SCC (21 high and 21 low grade), 20 cases of VC and 8 cases of normal oral mucosa using immunohistochemistry. There were significant differences among the study groups regarding the number of cells expressing p53, MMP-2 and 9. Except for Ki-67, other studied markers can be used for the histological grading of SCC and its differentiation from VC. MMP-9 is the most reliable one for invasive SCC grading. The extent of the expression of these markers is related to the infiltration pattern of SCC at the invasive front. The less invasive nature of VC can be associated with the expression pattern of these markers.