Expression of vascular endothelial growth factor family members in head and neck squamous cell carcinoma correlates with lymph node metastasis

Background. The expression of vascular endothelial growth factor (VEGF)-A i soforms (121, 165, 189, 206), VEGF-B, VEGF-C and VEGF-D in both experimenta l and clinical models of head and neck squamous cell carcinoma (HNSCC) was determined and correlated with conventional clinicopathologic parameters, w ith particular reference to cervical nodal metastasis. Methods. The mRNA expression of VEGFs in 14 HNSCC cell lines was compared w ith 4 normal keratinocyte cultures and 10 fibroblast cultures using a semiq uantitative reverse transcription polymerase chain reaction (RT-PCR) assay. Protein levels were determined by Western blotting and enzyme-linked immun osorbent assay (ELISA). The authors then examined the expression of VEGFs i n tissues from 54 patients including histologically normal epithelium (n = 32), early invasive squamous cell carcinomas (SCCs) (n = 23), advanced prim ary SCCs (n = 31), and lymph node metastases (n = 27). Results. Increased levels of VEGF-A (all four isoforms) and VEGF-C were fou nd in tumor cell lines compared with normal cells, whereas no differences i n VEGF-B levels were found. VEGF-D expression, however, was lower in HNSCC cells. Studies in clinical samples showed highly significant increases in m RNA expression of all four isoforms of VEGF-A and VEGF-C in tumors versus n ormal epithelium. In contrast, the levels of VEGF-D were significantly decr eased in tumors, and VEGF-B expression appeared similar in both normal and malignant tissues. Multivariate analysis demonstrated that an infiltrative mode of invasion and enhanced expression of VEGF-A (isoforms 121 and 165) a nd VEGF-C had predictive value for the presence of cervical nodal metastase s. Conclusions. Up-regulation of VEGF-A (two isoforms) and VEGF-C and downregu lation of VEGF-D have been common features in HNSCC. Thus VEGF-A and VEGF-C appeared to play a vital role in the metastatic process of HNSCC. Cancer 2 001;92:356-68. (C) 2001 American Cancer Society.