Expression of genetic markers in lymph node metastases compared with their primary tumours in head and neck cancer

Abstract

Regional metastasis is an important factor in the prognosis and treatment of head and neck squamous cell carcinoma (HNSCC). The results of earlier studies suggested the possibility of predicting nodal metastasis in HNSCC using biological markers. To identify which factors may be relevant in the metastatic behaviour of these tumours, the expression of several markers involved in tumour progression was studied in both nodal metastases and their corresponding primary tumours. Expression of p53, Rb, cyclin D1, myc, bcl-2, EGFR, neu, E-cadherin, epithelial cell adhesion molecule (Ep-CAM), and nm23 was studied in 54 primary tumours and their corresponding metastases in patients with HNSCC. The expression of most genes involved in tumourigenesis (p53, Rb, cyclin D1, myc, bcl-2, EGFR, neu, and E-cadherin) was similar in primary tumours and metastases. The expression of nm23 and Ep-CAM was found to be more frequently lower than higher in metastases, compared with their primary tumours. Whereas most genetic alterations of primary tumours remain unchanged in metastases, expression of the cell adhesion molecule Ep-CAM and of nm23 is more frequently reduced than increased in metastases, compared with their primary tumours, suggesting relevance to the process of metastasis. This also implies differences in the regulation of markers involved in tumourigenesis and the process of metastasis.