[Detection of an "autocrine loop" between EGF receptor and TGF-alpha in head-neck carcinomas]

In order to find a prognostic marker for the course of disease in head and neck cancer, we hypothesized that patients with rapid disease progress would produce increased levels of transforming growth factor alpha (TGF-alpha) and its cell surface receptor, the epidermal growth factor receptor (EGFR).

Using molecular biological techniques, we examined the incidence of TGF-alpha and EGFR expression in 43 patients with tumors of the head and neck. The expression data were correlated with the course of disease in four-year follow-up. The tumors were classified into four groups according to the EGFR status: Group 1, no expression for EGFR (15 samples); group 2, expression level 10 for EGFR (18 samples); group 3, expression level 50 for EGFR (7 samples); and group 4, expression level 100 for EGFR (3 samples).

An expression for the TGF-alpha protein was only detected in group 4. There was a significant correlation with EGFR overexpression in group 4 and survival compared with group 3 (p < 0.01) and group 1 (p < 0.05). The mean survival for group 1 to 4 was 27, 33, 34, and 10 months, respectively.

The analysis of all patients revealed that the patients with synchronous expression of EGFR and TGF-alpha had the poorest prognosis. Increased production of TGF-alpha and EGFR in tumors of the head and neck may serve both as a marker for tumor progression and as a target for preventive therapies.