Identification of D-Gal and Gal/GalNac Terminal Sugars in Basal and Squamous Cell Carcinomas of the Skin

Basal and squamous cell carcinomas comprise 90% of all skin malignancies. Cell surface and extracellular glycoconjugates change in neoplastic cells along with morphological changes of cancer cells. In many cases of malignant diseases, these changes of terminal sugars are responsible for invasive and metastatic properties of cancer cells. Recent studies have shown that the reaction of cancer cells change to lectins in course of neoplastic changes. The aim of the present study was to identify D-Gal and Gal/GalNac in basal and squamous cell carcinomas of the skin. In this descriptive study paraffin blocks of a total number of 20 patients (10 SCC and 10 BCC) were selected from pathology file of Khatam Al Anbia hospital in Zahedan. After confirmation of previous diagnosis, from each block 4 sections were prepared and stained by WGA and PNA/Alcian blue (pH=2.5). After staining, sections were studied blindly by two persons. Histopathological reports were prepared according to staining intensity and the location of reaction to lectins. Brown precipitate in cell and extracellular matrix were recognized as positive reaction. The presence of Gal/GalNac terminal sugar was confirmed by PNA lectin in squamous cell carcinoma of the skin. The nuclei of cancer cells did not react to lectin. Cancer cells in Basal cell carcinoma did not react to WGA lectin for D-Gal terminal sugar either. The presence of D-Gal was confirmed in basal cell carcinoma. Neoplastic cells in squamous cell carcinoma did not react to WGA. It seems that in neoplastic changes, terminal sugars of glycoconjugate change with different patterns in skin malignancies, so that PNA lectin is a good marker for SCC and WGA for BCC.