[Morphology of epithelial-mesenchymal transformation in neoplasias of oral mucosa]

[To the question of proliferative verrucous leukoplakia malignant potential]

AIM OF STUDY

To study of neoplastic transformation of the epithelial cells of the oral mucosa with verrucous hyperortokeratosis, verrucous carcinoma and oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Oral mucous membrane biopsies of 33 patients with clinical diagnosis of proliferative verrucous leukoplakia were investigated. Histologically in 19 cases (57.6%) was revealed verrucous hyperorthokeratosis, in 8 cases (24.2%) - verrucous carcinoma and in 6 cases (18.2%) - oral squamous cell carcinoma. Tissue antigens were determined using mouse monoclonal antibodies to Ki-67 and mouse monoclonal antibodies to cytokeratin 15.

RESULTS OF THE STUDY

In comparison with the proliferative activity of epithelial cells in the malpighian layer in verrucous hyperorthokeratosis (17.2±8.1%) was detected increasingof cell proliferation in epithelial growth zone in verrucous carcinoma (33.8±8.1%) and in peripheral zone of solid areas in oral squamous cell carcinoma (51.2±35.7%). A significant decrease in the expression of cytokeratin 15 in the cytoplasm of tumor cells was noted inverrucous carcinoma and oral squamous cell carcinoma in comparison with verrucous hyperorthokeratosis.

CONCLUSION

The obtained results proclaim that there is no stage of epithelial dysplasia during tumor transformation of proliferative verrucous leukoplakia into verrucous carcinoma and oral squamous cell carcinoma. Verrucous carcinoma by the nature of proliferative activity, cell atypia and expression of cytokeratin 15 corresponds to carcinoma in situ.

[Immunohistochemical study of Ki-67, PHH3, and CK15 protein expression in oral epithelial malignancy]

OBJECTIVE

To investigate the expression of Ki-67, phosphohistone H-3 (PHH3), and cytokeratin 15 (CK15) proteins in the cells of the oral mucosa (OM) according to the degree of its malignant transformation.

MATERIAL AND METHODS

OM biopsy specimens from 69 patients diagnosed with focal epithelial hyperplasia, intraepithelial squamous cell neoplasia, cancer in situ, and squamous cell carcinoma were examined. Tissue antigens were determined using mouse Ki-67 monoclonal antibodies, rabbit PHH3 polyclonal antibodies, and mouse CK15 monoclonal antibodies.

RESULTS

There was an increase in epithelial proliferative and mitotic activities in squamous cell carcinoma and a sharp decrease in the expression of CK15 in the cytoplasm in cancer in situ and squamous cell carcinoma of the OM.

CONCLUSION

The protein CK15 can be used for the differential diagnosis between high-grade dysplasia and OM epithelial malignancy at the stage of carcinoma in situ and squamous cell carcinoma.

[The role of Sonic Hedgehog signaling pathway in the development of oral squamous cell carcinoma]

The research of the Sonic Hedgehog signaling pathway activity was carried out on biopsy specimens of 43 patients with oral hyperplasia, squamous intraepithelial neoplasia and oral squamous cell carcinoma. Tissue antigens were determined using a mouse monoclonal antibody to Ki-67 protein and rabbit monoclonal antibody to Gli-1 protein. In squamous intraepithelial neoplasia and oral squamous cell carcinoma specimens Gli-1 was detected in the cytoplasm of cells only. The correlation was found between the proliferative activity of epithelial cells and Gli-1 distribution. Protein Gli-1 can be used for early diagnosis of malignant transformation of oral stratified squamous epithelium.