Immunohistochemical expression of cathepsin D and matrix metalloproteinase-9 in common epidermal tumors

Background Cathepsin D and matrix metalloproteinase-9 (MMP-9) are proteolytic enzymes that degrade connective tissue in the extracellular matrix and play a major role in the destruction of the basement membrane. Objective To explore immunohistochemical expression of cathepsin D and MMP-9 in basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and seborrheic keratosis (SK). Patients and methods This retrospective study included 45 patients classified into the following groups: group I, 15 patients with SK; group II, 15 patients with BCC; group III, 15 patients with SCC; and group IV, control group, which included 10 age-matched and sex-matched individuals with normal healthy skin. All participants were subjected to hematoxylin and eosin stain and immunohistochemical staining for cathepsin D and MMP-9. Results A statistically significant increase in the intensity of expression of cathepsin D and MPP-9 in the SCC, BCC, and SKs was found in the patient groups than the control group. The expression of both markers was significantly higher in SCC than in BCC and SK. The expression of both markers was significantly higher in BCC with a high risk of recurrence than in those with a low risk of recurrence, and was significantly positively correlated with advancement in histological grade in SCC. Conclusion The cytoplasmic expressions of cathepsin D and MMP-9 were prominent in stromal and epithelial cells of SCC than in BCC and SK. This pointed to the capability of SCC of invasion as well as metastatic potentiality than in BCC and SK.