p150 expression and its prognostic value in squamous-cell carcinoma of the esophagus

To investigate p150, a recently cloned protein, and its prognostic value in esophageal squamous-cell carcinoma, 100 samples were analyzed immunohistochemically and 30 fresh samples by the immunoblot method. All 100 patients, from Northern China, over-expressed p150 as compared with controls in the immunohistochemical study, and the same was found for the tumors of the 30 patients analyzed by Western-blot analysis. A close correlation could be observed between p150 over-expression and the state of differentiation, since well-differentiated cancers showed high p150 expression, and vice-versa (p < 0.0001). In addition, patients with high p150 expression had significantly fewer tumor metastases (local or distant, p < 0.005). Furthermore, and prognostically more relevant, survival analysis showed that patients with high p150 expression had significantly better overall survival (p < 0.0026). This somehow unexpected result may, however, be typical for squamous carcinoma, since in human cervical carcinoma, another squamous carcinoma, the p150 values were reported to rise early in all tumors, to stay high in patients with longer survival as well. In addition, patients with regional lymph-node metastasis and high p150 expression survived longer than those with regional lymph-node metastasis and lower p150 expression (p < 0.0066). Multivariate analysis showed that p150 is an independent factor for predicting patient survival. The results suggest that p150 may be a new biomarker for squamous-cell carcinoma of the esophagus, with specific prognostic value.